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Objectives: To analyze the three‐dimensional stability and morphologic changes of tent space after the osteotome sinus floor elevation (OSFE) procedures without bone grafts. Materials and Methods: Forty‐six implants placed using the OSFE technique with simultaneous implant placement without bone grafts were included in this retrospective study. Cone‐beam computed tomography (CBCT) scans of the augmented sinuses were obtained pre‐ and postoperatively up to 48 months of follow‐up. The maxillary sinus cavity profiles were outlined using three‐dimensional virtual reconstruction and superimposition of CBCT scans. The three‐dimensional changes in the tent space were measured. A generalized estimating equation (GEE) was used to explore potential factors. Results: The implant survival rate was 97.8%. The mean volume of remaining tent space immediately after surgery was 96.8 ± 70.5 mm3, shrinking to 31.0 ± 24.9 mm3 after 48 months, while the mean percentage of remaining tent space volume decreased to 29.1 ± 20.7%. The tent space volume and the percentage of residual tent space volume only decreased significantly within 12 months after surgery (p =.008,.013). GEE results indicated positive correlations between the percentage of remaining tent space volume and implant protrusion length (p =.000) and apical height (p =.000), with a negative correlation between the sinus floor area immediately after surgery (p =.002) and the healing time (p =.022). Conclusions: The volume of the tent space rapidly shrank after OSFE without bone grafts. Several factors might influence the tent space stability. Long‐term clinical trials with larger sample sizes are necessary to further validate the results. [ABSTRACT FROM AUTHOR]

This study aimed to compare implant stabilities between the immediate and early loaded, immediately placed bone‐level tapered dental implants in the maxilla and to evaluate marginal bone loss (MBL), oral health‐related quality of life (OHRQoL), and patient satisfaction at a 2‐year follow‐up. A pilot, prospective, randomized, controlled clinical trial was conducted on 24 maxillary failing dentition patients. The bone‐level tapered implants of 12 patients were immediately loaded with temporary restorations, while the other 12 patients did not receive any kind of temporization. Implant‐supported screw‐retained complete porcelain‐fused‐to‐metal prostheses were delivered to all patients in the seventh postoperative week. The insertion torque values of implants assigned to the immediate and early loading groups were 33.0 ± 4.87 and 29.26 ± 8.31 Ncm, respectively. The dynamics of implant stability changes from implant placement up to a 2‐year follow‐up were similar for both groups (Penguin®, p = 0.268; Ostell®, p = 0.552), while the MBL was at submillimeter level. The cumulative implant survival rate was 91.80% for immediately loaded implants and 97.22% for early loaded implants, without significant difference (p = 0.162). The total score on the Oral Health Impact Profile questionnaire significantly decreased over time in both groups, indicating improvement in OHRQoL (p < 0.001), and the high level of patient satisfaction remained after 2 years of function regardless of a loading protocol. Both loading protocols, immediate and early, of six immediately placed bone‐level tapered dental implants are an adequate treatment choice for fixed rehabilitation of the maxillary failing dentition. [ABSTRACT FROM AUTHOR]

Objectives: To determine the correlation between the primary implant stability quotient and the implant percussion sound frequency. Materials and Methods: A total of 14 pigs' ribs were scanned using a dental cone beam computed tomography (CBCT) scanner to classify the bone specimens into three distinct bone density Hounsfield units (HU) value categories: D1 bone: >1250 HU; D2: 850–1250 HU; D3: <850 HU. Then, 96 implants were inserted: 32 implants in D1 bone, 32 implants in D2 bone, and 32 implants in D3 bone. The primary implant stability quotient (ISQ) was analyzed, and percussion sound was recorded using a wireless microphone connected and analyzed with frequency analysis software. Results: Statistically significant positive correlations were found between the primary ISQ and the bone density HU value (r = 0.719; p < 0.001), and statistically significant positive correlations between the primary ISQ and the percussion sound frequency (r = 0.606; p < 0.001). Furthermore, significant differences in primary ISQ values and percussion sound frequency were found between D1 and D2 bone, as well as between D1 and D3 bone. However, no significant differences were found in primary ISQ values and percussion sound frequency between D2 and D3 bone. Conclusion: The primary ISQ value and the percussion sound frequency are positively correlated. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the associations between the cortical bone‐to‐implant contact (CBIC), bone microstructure derived from cone‐beam computed tomography (CBCT), and the primary stability of the implant. Materials and Methods: Twenty‐two patients with 65 implants were enrolled in this study. The peak insertion torque values (ITVs) were measured during implant insertion, and the implant stability quotient (ISQ) values were measured immediately after implant placement and 3 months after surgery. The profiles of the peri‐implant bone structure were outlined using the volumetric reconstruction of the CBCTs and superimposition of the virtual models, and the features of CBIC and bone microstructure parameters were measured. The linear mixed effects model and generalized estimating equation were used to explore the predictors for implant primary stability. Results: The average ITV, baseline, and secondary ISQ values were 31.44 ± 6.54 N·cm, 73.34 ± 7.39, and 80.32 ± 4.58, respectively. Statistically significant correlations were found between ITV and surface area of CBIC (r =.340, p =.006), bone volume fraction (r =.294, p =.017), and bone surface fraction (r = −.278, p =.039). Implants with buccolingual CBIC had a higher ITV than implants without CBIC (p =.016). None of the parameters were associated with baseline and secondary ISQ values in generalized estimating equation analysis (all p >.05). Conclusions: Within the limitations of the study, preoperative CBCT measurements might enable the prediction of ITV and therefore of implant primary stability values. [ABSTRACT FROM AUTHOR]

Introduction: Implant stability is influenced by bone density, implant design, and site preparation characteristics. Piezoelectric implant site preparation (PISP) has been demonstrated to improve secondary stability compared with conventional drilling techniques. Osseodensification drills (OD) have been recently introduced to enhance both bone density and implant secondary stability. The objective of the present multi‐center prospective randomized controlled trial was to monitor implant stability changes over the first 90 days of healing after implant bed preparation with OD or PISP. Methods: Each patient received two identical, adjacent or contralateral implants in the posterior maxilla. Following randomization, test sites were prepared with OD and control sites with PISP. Resonance frequency analysis was performed immediately after implant placement and after 7, 14, 21, 28, 60, and 90 days. Implants were then restored with single screw‐retained metal‐ceramic crowns and followed for 12 months after loading. Results: Twenty‐seven patients (15 males and 12 females; mean age 63.0 ± 11.8 years) were included in final analysis. Each patient received two identical implants in the posterior maxilla (total = 54 implants). After 1 year of loading, 53 implants were satisfactorily in function (one failure in test group 28 days after placement). Mean peak insertion torque (40.7 ± 12.3 Ncm and 39.5 ± 10.2 Ncm in test and control group, respectively) and mean implant stability quotient (ISQ) value at baseline (71.3 ± 6.9 and 69.3 ± 7.6 in test and control group, respectively) showed no significant differences between the two groups. After an initial slight stability decrease, a shift to increasing ISQ values occurred after 14 days in control group and after 21 days in test group, but with no significant differences in ISQ values between the two groups during the first 90 days of healing. Conclusion: No significant differences in either primary or secondary stability or implant survival rate after 1 year of loading were demonstrated between implants inserted into sites prepared with OD and PISP. [ABSTRACT FROM AUTHOR]

Purpose: This randomized clinical trial compared 12-month outcomes of narrow platform implants (NP) or regular platform implants (RP) in beds prepared with conventional versus ultrasonic osteotomy and immediately loaded., Materials and Methods: Patients requiring narrow (3.0 mm) or regular (3.75 mm) implants in the upper esthetic zone were randomly allocated for conventional (10 NP, 15 RP implants) or ultrasonic (10 NP, 15 RP) osteotomy. Primary and secondary implant stability, operation time, patient discomfort, and probing depths were evaluated after different time periods., Results: Implant bed preparation time was longer (p < 0.001) with ultrasonic osteotomy versus conventional drilling (CD) in both RP and NP groups. Post-operative pain was lesser with ultrasonic preparation on postsurgical days 1 (p = 0.022) and 7 (p < 0.001) in the RP group and days 1, 4, and 7 (p = 0.015, p = 0.019, p = 0.003) in the NP group. Secondary stability at 3 months was higher in the NP group with ultrasonic preparation versus CD (p = 0.002). No significant differences in probing depth were found between 3 and 12 months in either group with either technique. The 12-month success rate was 100% in both groups with both preparations., Conclusions: Regular diameter implants in beds prepared by ultrasonic osteotomy have comparable primary and secondary stability to those in beds prepared by conventional osteotomy and can be immediately loaded, showing a similar 12-month success rate. Narrow diameter implants placed in beds prepared by ultrasonic osteotomy have comparable primary stability values to those in conventionally prepared beds, but implant stability quotient values were always insufficient for immediate loading., (© 2025 by the American College of Prosthodontists.)

Objective: To compare the clinical outcomes of extra‐short implants (≤6.5 mm) inserted with one‐stage versus two‐stage technique in adjacent sites of the upper or lower jaw. Materials and Methods: In this split‐mouth multicenter study, implants were randomly divided into two groups according to the healing phase: two‐stage and one‐stage technique. Primary outcome measures were implant survival, implant success, and prosthodontic complications. Secondary outcome measurements were: implant stability quotient (ISQ) collected at surgery time (T0), and after 3 (T3) and 12 (T12) months, marginal bone level (MBL) evaluated at T0, T3, T6, and T12, marginal bone loss evaluated at T6 and T12, plaque index (PI), probing depth (PD), bleeding on probing (BoP) evaluated at T3, T6, and T12. Significances of differences between groups were tested by linear mixed model with random intercept. Results: Nineteen patients (8 males and 11 females) were included. A total of 38 implants were inserted. At T12 implant cumulative survival and implant success rate were 100% in both groups. No statistically significant differences were recorded for any of the analyzed parameters between the two groups at any time point. ISQ values were similar at T0 (two‐stage: mean 67.53 ± SD 19.47; one‐stage: mean 66.53 ± 19.07 p = 0.8738) and increased in both groups at the 12‐month follow‐up appointment (two‐stage: 81.1 ± 7.04; one‐stage: 81.39 ± 0.9266). MBL values were similar in the two groups at any time point. At T12 marginal bone loss was 0.46 ± 0.41 (two‐stage) and 0.45 ± 0.38 (one‐stage) mm (p = 0.9417), while mean PD was 2.7 ± 0.85 (two‐stage) and 2.69 ± 0.89 (one‐stage) mm. Conclusions: Within the limits of the present short‐term report, extra‐short implants demonstrated optimal clinical outcomes using the one‐stage technique, without statistically significant differences compared with the traditional two‐stage approach. [ABSTRACT FROM AUTHOR]

Objective: This study intended to ascertain the dimensional effects of labial bone thickness and height on the mechanobiological stimuli distribution of maxillary anterior labial bone through biomechanical analysis. Material and methods: Twelve 3D finite element models of an anterior maxillary region with an implant were computer‐simulated, including four levels of labial bone thicknesses (2, 1.5, 1.0, and 0.5 mm) and three levels of labial bone heights (normal, reduced by 1/3, reduced by 1/2). A 45° buccolingual oblique load of 100 N was applied to the implant restoration. Results: Equivalent stress and principal strain mainly concentrated on crestal bone around the implant neck. The maximum equivalent stress in bone decreased as labial bone mass decreased, while the maximum principal strain and the displacement of dental implant increased as labial bone mass decreased. No significant difference of these three indicators was observed, when the labial bone thickness changed in the range of 2.0–1.0 mm with sufficient labial bone height. Conclusions: In terms of biomechanics, the thickness of labial bone plate was recommended ≥1 mm. Sufficient labial bone height was warranted to prevent the stability of the implants from being seriously affected. The labial bone heights were more effective than thicknesses on the mechanobiological stimuli response of the dental implant‐bone system. Clinical significance: For this 3D finite element study, the biomechanical responses under different bone mass conditions were explored, in order to predict the process of bone remodeling and provide valid clinical recommendations for the decision‐making process regarding the choices of tissue augmentation for some specific esthetic implantation cases for future clinical applications. [ABSTRACT FROM AUTHOR]

Introduction: There are several factors that greatly influence implant stability with implant design being a paramount factor; however, few studies investigate its impact. Aim: To investigate the implant stability in relation to two different implant designs, a cylindrical shaped single‐threaded design (CS/ST) and a tapered shaped double‐threaded design (TS/DT) using resonance frequency analysis over the first 8 weeks after implantation. Materials and Methods: Twenty‐eight implants were randomly allocated using computer‐generated random numbers into two groups and were placed as single tooth implant in the posterior arch in human jaw as specimens. iCAT™ CBCT scan (Hatfield, PA) was used to determine the bone density according to Misch's Bone classification. The osseotomy sites were prepared and implants were placed with guided surgical template by inexperienced surgeons which were prepared with the same implant planning software (3shape® implant studio). The implant stability was measured using the resonance frequency analysis Osstell® ISQ (Osstell AB, Sweden) on the implant level over the first 8 weeks at three different time intervals. A mean implant stability quotient (ISQ) value was recorded at each measurement time points. The first ISQ of each implant recorded at the time of implant placement were considered as baseline and were the so‐called primary stability. Results: All 28 dental implants were analyzed. A similar pattern of implant stability changes was observed in both implant designs. A significant decreased was found at the first 4 weeks after implantation (p < 0.05) before ascending to maximum cumulative stability by the eighth week (p < 0.05). Between the two groups, TS/DT group had a higher mean ISQ values than that of the CS/ST group at all three observation periods but did not reach statistical significance (p = 0.69). Regarding different types of bone, TS/DT showed a significant difference in mean ISQ values in D4 bone. To date, all 28 implants are in function with no failure/and or complications. Conclusions: The difference in implant design did not significantly influence the implant stability. TS/DT shows superiority over CS/ST when placed in D4 bone and offer a significant advantage due to their positive bounce back of the ISQ values by the eighth week after implant installation. Clinical Trial Registration: TCTR20211020005. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to evaluate long‐term in vivo stability of dental implants stabilized at time of placement in oversized osteotomies with a novel, self‐setting, mineral–organic bone adhesive. Materials/Methods: Canine (26) mandibular teeth were removed, and three oversized osteotomies prepared bilaterally. Implants were placed with either adhesive, particulate xenograft, or with blood clot filling the implant/osteotomy gaps. Removal torque and histology were assessed. Results: The adhesive provided significant and clinically relevant immediate implant stability of 22.2 N‐cm (95% CI 5.3; 39.0), which continued throughout the early postoperative course and persisted through the nine‐ (155 N‐cm 95% CI 113; 197) and 12‐month (171 N‐cm 95% CI 134.2; 209.4) time points. This is in comparison with the blood clot of 1.4 N‐cm (95% CI 0.7; 2.1), 128.6 N‐cm (95% CI 66.8; 190.4), and 140.7 N‐cm (95% CI 78.8; 202.5) and particulate xenograft, 1.3 N‐cm (95% CI 0.6; 2.0), 132.1 N‐cm (95% CI 94.5; 169.7), and 101.5 (95% CI 59.5; 143.5), respectively. Histological examination shows the adhesive establishes intimate contact with the implant and bony walls and is replaced with new bone without compromising stability. Soft tissue does not penetrate the adhesive, and marginal bone/biomaterial level is maintained. Control sites filled with xenograft or blood clot heal with reduced bone levels, and in some cases, xenograft particles were encapsulated in connective tissue. Conclusions: Implants placed in oversized osteotomies and lacking primary stability can be stabilized at placement with a novel, highly osteoconductive, and resorbable adhesive. Gradual replacement of the biomaterial allows osseointegration without loss of stability through 12 months of follow‐up. This novel adhesive has the potential to stabilize implants placed in sites with inadequate bony support. [ABSTRACT FROM AUTHOR]

Inappropriate and unnecessary implant therapy driven by an erroneous belief that dental implants provide enhanced function and esthetics over diseased or failing teeth has led to a growing burden of implant complications across the globe. Specifically, esthetic and biological complications frequently lead to the unfavorable prognosis of dental implants. Often, these cannot be managed predictably to improve the condition or satisfy patients' demands. In such circumstances, implant removal needs to be considered. Currently, minimally invasive methods based on reverse torque engineering are key to preserve peri-implant soft and hard tissues. Implant replacement is now feasible, as evidenced by the high survival rates of implants placed at previously failed sites. Notwithstanding these data, clinicians should still consider carefully the expendability of an implant and whether its replacement will satisfy the prosthetic, biomechanical, and esthetic demands of the patient. In the scenario where future implant placement is desired, protocols undertaken for soft/hard tissue grafting and implant placement should be based upon defect morphology and soft and hard-tissue characteristics. Currently, however, a lack of knowledge of the biological events and dimensional changes that arise following implant removal renders decision-making complex and challenging, and recommendations remain largely based upon empirical speculation. This chapter will review the indications for implant replacement for prosthetic, biomechanical, and esthetic complications, alongside considerations in decision-making, planning, implementation, and outcomes of implant replacement. [ABSTRACT FROM AUTHOR]

Objectives: Resonance frequency analysis (RFA) is used to monitor implant stability. Its output, the Implant Stability Quotient (ISQ), supposedly correlates with insertion torque, a common measurement of primary stability. However, the reliability of RFA in condensed bone remains unclear. Material and methods: In this human cadaver study in edentulous jaws and fresh extraction sockets, implants were inserted using a split‐mouth approach into condensed or untreated bone. Mean ISQ, peak insertion torque, and pre‐ and postoperative bone volume fractions (BV/TV) were assessed. Results: In edentulous jaws, insertion torque and ISQ correlated both in untreated (r = 0.63, p = 0.02) and in condensed (r = 0.82, p < 0.01) bone. In extraction sockets, insertion torque and ISQ only correlated in untreated (r = 0.78, p < 0.01), but not in condensed bone (r = 0.15, p = 0.58). In all edentulous jaws, preoperative BV/TV correlated with insertion torque (r = 0.90, p < 0.0001), ISQ (r = 0.64, p < 0.001), and changes in BV/TV (r = –0.71, p < 0.01). In all extraction sockets, preoperative BV/TV did not correlate with either insertion torque (r = 0.33, p = 0.15), ISQ (r = 0.38, p = 0.09), or changes in BV/TV (r = –0.41, p = 0.09). Joint analysis identified preoperative BV/TV as a predictor of postoperative BV/TV (p < 0.001), insertion torque (p < 0.001), and ISQ (p < 0.001). Conclusions: RFA is feasible for monitoring stability after late implant placement into condensed bone, but not after immediate placement into condensed fresh extraction sites. [ABSTRACT FROM AUTHOR]

Background: The ability to restore missing teeth with dental implants is dictated by the available bone and by the presence of anatomical structures. The potential to insert ultrashort implants avoids additional surgical procedures and its inherent complications. The last European Association of Dental Implantologists consensus in 2016 defined ultrashort implants and standard‐length dental implants as <6 and >8 mm, respectively. Purpose: The present study aimed to investigate whether single standing ultrashort dental implants (US) could provide a viable therapeutic alternative to osteotome mediated sinus floor elevation in combination with standard‐length dental implants (SL) 10 mm in posterior maxillary rehabilitation with reduced bone height. Materials and Methods: The study was conducted as a prospective parallel group controlled clinical trial with a 12 month follow‐up, where 48 implants were randomized into two groups; US‐group (5.5 mm) and SL‐group (10 mm) implants placed with osteotome‐mediated sinus floor elevation. Crestal bone loss (CBL) was defined as the study's primary outcome, while implant survival, buccal bone thickness, implant stability, probing depth, gingival recession, and adverse effects were assessed as secondary outcomes. Results: Mesial CBL was 1.13 ± 0.52 mm in SL‐ and 0.72 ± 0.52 mm in US‐group (P =.021), while distal CBL was 1.44 ± 0.72 mm in SL‐ and 0.91 ± 0.69 mm in US‐group at 12 months (P =.0179). Regarding implant stability, probing depth, and gingival recession there was no statistically significant difference between the two groups. Regarding implants' survival, three implants were lost in the US‐while only one implant was lost in the SL‐group (P =.6085; Fisher's exact test). Nevertheless, the ultrashort implants were associated with a tripling of the failure rate and uncertainty where the true failure rate is uncertain (relative risk 3.0; confidence interval 0.3‐26.8). Conclusions: Within the current trial's limitations, US‐appear appear promising as they are associated less postoperative discomfort, minimal invasiveness and less CBL. However, larger sample size is required to determine whether the ultrashort have an acceptable survival rate. [ABSTRACT FROM AUTHOR]

Background: Following free fibula flaps (FFF) reconstruction of mandibular defects the patients need an early dental rehabilitation to regain their masticatory function and enhance their feeding and nutrition. Methods: This study included 10 patients, with mandibular defects previously reconstructed with FFF that span the area between the two mandibular angles. They received a full arch fixed restoration supported by four implants using a pilot drilling guide to perform a flapless operation. The stability of the placed dental implants was assessed along with the changes in bone density. Results: There was a statistically significant increase in stability after 3 and 6 months, and there was a decrease in density after 6 months. The patient satisfaction improved over the follow‐up period. Conclusion: The All‐on‐Four technique is reliable and economic for early functional rehabilitation of resected jaws reconstructed with FFF; however, further studies are needed to investigate the changes in fibula bone density over time and with function. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the ex vivo effect of cyclic loading on the stability of screws placed in locking plates used to bridge segmental bone defects. The primary interface stability was assessed using peak reverse torque. Eighteen, 8‐hole stainless‐steel 4.5 mm locking plates and 4.0‐mm self‐tapping locking‐head screws were used to stabilize 40‐mm segmental defects in goat tibiae. Treatment groups included control constructs without cyclic loading (n = 6) and constructs tested to 5000 (n = 6) and 10,000 cycles (n = 6) of 600 N compressive axial loading. The insertion of all screws was standardized to 400 N‐cm insertion torque. Peak reverse torque was measured immediately after screw placement (control), or after the completion of the respective loading cycles. The difference between treatment groups was compared using univariate analysis of variance. The analysis revealed a significant difference in peak reverse torque of the screws among the treatment groups (p =.000). The mean reverse torque values equaled 343.5 ± 18.3 N‐cm for non‐cycled controls, 303.3 ± 25.9 and 296.0 ± 42.9 N‐cm after 5000 and 10,000 cycles, respectively. Among all treatment groups, screws placed in the distal bone segment tended to have lesser peak reverse torque reduction than those placed in the proximal segment and the difference was proportional to the number of cycles (p =.562; p =.255; p =.013 in control, and after 5000 and 10,000 cycles, respectively). Cyclic loading may have a negative effect on the primary stability of screws placed in locking plate constructs used to bridge segmental bone defects and could contribute to the risk of screw loosening. [ABSTRACT FROM AUTHOR]

Purpose To investigate the feasibility of reducing the healing time of maxillary sinus floor elevation (MSFE) by a two‐stage approach using deproteinized bovine bone mineral (DBBM) alone, based on clinical, histomorphometric, and microradiographic evaluations. Materials and Methods: Twenty consecutive cases with an atrophic posterior edentulous maxilla were randomly assigned to two groups at a ratio of 1:1. The lateral window approach to MSFE with DBBM alone was followed by an 8‐month bone‐healing period in the control group compared to 5 months in the test group. During implant placement, bone biopsies were harvested from implant osteotomy sites for micro‐computed tomography (CT), histological, and histomorphometric evaluations. Cone beam CT (CBCT) scans were performed before and immediately after MSFE and after the bone‐healing periods. The implant stability quotient (ISQ) was measured sequentially at implant placement and 1, 3, and 6 months thereafter. Results: The histomorphometric and microradiographic results showed no significant differences in new bone formation on the augmented sinus floor between the two groups (all Ps >.05), except that trabecular thickness was significantly reduced and trabecular separation significantly increased in the test group (both Ps <.05). The ISQs of both groups increased continuously after implant placement, but the difference was not significant between the groups at each time point. CBCT analyses showed that the extent of volumetric loss was comparable after bone healing for 5 and 8 months (P >.05). Conclusions: Within the limitations of this study, the bone‐healing time of MSFE with DBBM alone for staged implant placement could be reduced to 5 months instead of 8 or 9 months, based on the histomorphometric, microradiographic, and clinical outcomes; however, impact on long‐term implant survival remains unknown and needs further investigation with long‐term follow‐ups. [ABSTRACT FROM AUTHOR]

Aims: The aim of the present study was to assess the association between dental implant stability and peripheral blood cell composition and levels of coagulation factors in patients treated with alveolar ridge preservation with platelet‐rich fibrin (PRF) and bovine bone substitute. Materials and methods: Fifty patients were included between 2015 and 2017. PRF was prepared from autologous blood, in which blood cells and coagulation factor levels were measured. PRF and bovine bone were placed in the socket, followed by closure with PRF membrane. Implants were placed 14 (±2.5) weeks postextraction. The implant stability quotient was measured at t = 0, t = 10 days, t = 7 weeks, and t = 17 weeks by resonance frequency analysis. Results: Erythrocyte count was inversely associated with PRF membrane length, but not with implant stability. Conversely, platelet count did not correlate with membrane size but inversely correlated with implant stability at 7 and 17 weeks. In addition, implant stability was directly correlated with levels FXIII (t = 0, p <.01), active von Willebrand factor (VWF; t = 0 and 7 weeks, p <.05), and total VWF (t = 7 weeks, p =.012). Conclusion: Implant stability following alveolar ridge preservation with PRF and bovine bone substitute is associated with circulating blood cells and coagulation factors. In particular, fibrin structure, VWF, and FXIII may be important modulators of implant stability. [ABSTRACT FROM AUTHOR]

Objectives: We performed a randomized clinical study evaluating the stability of implants with different surfaces (alkali‐modified or sandblasted) via resonance frequency analysis (RFA). Materials and Methods: Fourteen patients who were bilaterally edentulous in terms of their mandibular molars were enrolled. Implants with alkali‐modified (bioactive) and sandblasted surfaces were randomly placed in either hemi‐arch; the 50 implants used were identical in terms of diameter and length. RFA was used to measure the implant stability quotient (ISQ) immediately after placement (to assess primary stability) and 2, 6, and 12 weeks later. Results: The average RFA value for alkali‐modified implants was significantly higher than that for sandblasted implants immediately after implantation, but the ISQs fell rapidly and were similar in the two groups at 2 and 6 weeks (p >.05); ISQ values were the same in the two groups at 3 months (p >.05). Conclusions: Implants with alkali‐modified surfaces were more stable than implants with sandblasted surfaces at all times after placement. The ISQs of bioactive implants exhibiting high‐level primary stability fell to greater extents than did those of implants with sandblasted surfaces at 2 and 6 weeks postoperatively; both types of implant yielded similar clinical results at 12 weeks postoperatively. [ABSTRACT FROM AUTHOR]

Background: There is a lack of long‐term evaluations of immediately loaded implants in patients with compromised maxillary bone. Purpose: To evaluate long‐term survival and success of immediately loaded implants in subjects with poor maxillary bone quality and volume. Material and methods: Follow‐up was performed on subjects who received six implants loaded within 24 hours with screw‐retained fixed prostheses. Twenty‐five subjects with limited bone (Lekholm and Zarb, quantity 3 and 4, and quality C and D) were included in the study. Nineteen participated in the radiographic examination and of these 17 participated in the clinical examination at the last visit. Evaluations of marginal bone loss were performed at 1, 3, 5, and 8‐11 years. The last clinical examination included removal of the prosthesis followed by registration of: plaque, pus, pocket depth, bleeding upon probing, mobility, and percussion testing. Results: The mean follow‐up was 9 years and 2 months (101‐131 months) after surgery and showed a cumulative implant survival rate of 81.9% and success rate of 74.7%. Mean marginal bone loss was 1.29 mm (SD 2.47 mm range 0‐11 mm) with a mean pocket depth of 3.1 mm (SD 2.4 mm, range 1.5‐13.5 mm). 42.5% of the implants showed plaque retention and 72.2% showed bleeding on probing. Conclusion: This nonaugmenting immediate loaded implant protocol for maxillary edentulous patients is a satisfactory solution for selected patients. [ABSTRACT FROM AUTHOR]

Objectives: Whereas stationary stability of implants has been postulated for decades, recent studies suggested a phenomenon termed implant migration. This describes a change in position of implants as a reaction to applied forces. The present study aims at employing image registration of in vivo micro‐CT scans from different time points and to assess (a) if migration of continuously loaded implants is possible and (b) migration correlates with the force magnitude. Material and methods: Two customized machined implants were placed in the dorsal portion of caudal vertebrae in n = 61 rats and exposed to standardized forces (0.5 N, 1.0 N, and 1.5 N) applied through a flat nickel–titanium contraction spring, or no forces (control). Micro‐CT scans were performed at 0, 1, 2, 4, 6, and 8 weeks after surgery. The baseline image was registered with the forthcoming scans. Implant migration was measured as the Euclidean distance between implant tips. Bone remodeling was assessed between the baseline and the forthcoming scans. Results: The findings confirmed a positional change of the implants at 2 and 8 weeks of healing, and a linear association between applied force and velocity of movement (anterior implant: χ2 = 12.12, df = 3, and p =.007 and posterior implant: χ2 = 20.35, df = 3, and p <.001). Bone apposition was observed around the implants and accompanied by formation of load‐bearing trabeculae and a general cortical thickening close and also distant to the implants. Conclusion: The present analysis confirmed that implants can migrate in bone. The applied forces seemed to stimulate bone thickening, which could explain why implants migrate without affecting stability. [ABSTRACT FROM AUTHOR]

Adequate implant stability is an essential requirement. The introduction of the Penguin resonance frequency analysis raises some questions regarding its reliability, reproducibility, and repeatability as well as how it compares to the older Osstell device. Purpose: To assess the newer Penguin implant stability coefficient (ISQ) device (vs the Osstell device). Materials and methods: A total of 120 implants were used, divided into four groups (A, B, C, and D) (according to design) and placed in fresh bovine bone. Consecutive measurements were made with both devices (Penguin/Osstell) with their respective transducers. Then, the ISQ values were measured with the Penguin device using the Osstell transducer, and vice‐versa. Results: The mean insertion torque (N/cm) values for the implants were as follows: Group A = 24.7 ± 9.4; Group B = 25.6 ± 9.7; Group C = 28.7 ± 7.9; Group D = 19.1 ± 5.5. The mean ISQ values for the entire sample were as follows: Penguin 67.7 ± 6.1 and Osstell 68.5 ± 9.6. The ISQ value measured with the Penguin device using a SmartPeg transducer was 67.0 ± 8.0, and that for the Osstell device using a MultiPeg transducer was 68.3 ± 7.5. The intraclass correlation coefficient (ICC) was calculated for the ISQ values obtained from both devices and was >0.90 for all transducers. When the ICC transducers were interchanged, the values were <0.77. Conclusions: Both ISQ devices allow for reliable and repeatable measurement of implant stability; however, the use of each device‐specific transducer is recommended. [ABSTRACT FROM AUTHOR]

Background: The implant design and the surgical technique are important parameters that can be modified to improve the implant primary stability. The aim of this study was to evaluate the role of the apical part of an implant on the implant stability of implants placed in Type II dense bone by novice and experienced clinicians.Methods: Implants with a progressive thread design (3.5 mm diameter, 11 mm length) were used. A total of 80 osteotomies were prepared in dense bone samples (quality Type II) by two clinicians with different levels of experience (novice and experienced) under the same surgical protocol. Two experimental groups were prepared. In the test group (apical stability), 40 implants were inserted with only 3 mm of the apical portion of the implant within the bone and without lateral contact between the residual implant length and the osteotomy walls. In the control group (full implant stability), 40 implants were inserted with full contact between the osteotomy walls and the implant surface. The stability of both groups (test and control) was evaluated using a resonance frequency analysis (RFA) (implant stability quotient [ISQ] values). Statistical comparisons between the groups were performed using the Kruskal-Wallis test with Dunn post-test for multiple comparisons.Results: The results did not show statistically significant differences (P > 0.05) in terms of primary stability between implants placed by novice or experienced clinicians in dense bone. The control group showed significantly higher ISQ values compared with the test group (P < 0.001). The apical implant stability contributed to ≈ 30% and 43% of the entire implant stability for novice and experienced clinicians, respectively.Conclusions: The apical portion of an implant plays a fundamental role in the entire implant stability and is independent on the clinician's experience. However, precise implant site preparation to guarantee apical implant anchorage is recommended. [ABSTRACT FROM AUTHOR]

Background: There are no studies that have assessed the implant stability quotient (ISQ) values of narrow diameter implants placed in artificial dense bone blocks at varying drilling speeds (DSs). Purpose: The aim of the present in vitro experiment was to compare the performance of OSSTELL and Penguin devices to evaluate implant stability at DSs of 800 and 2000 rpm. Materials and Methods: A total of 360 osteotomies were created in dense artificial bone blocks at DSs of 800 and 2000 rpm. Dental implants from three manufacturers (group‐1: NobelActive implants, Nobel Biocare, Yorba Linda, California; group‐2: Zimmer, Eztetic‐Zimmer implants, Zimmer Biomet Dental, Palm Beach Gardens, Florida; and group‐3: Astra Tech implant system, Dentsply Sirona, York, Pennsylvania) were randomly placed in these osteotomies using an insertion torque of 15 Ncm (60 implants/group). Implant stability in all bone blocks immediately following implant placement was evaluated using the OSSTELL and Penguin devices. ISQ values were presented as means ± SD. Statistical significance was set at P < .05. Results: There was no significant difference in the ISQ values obtained from the OSSTELL and Penguin devices for implants in groups 1, 2, and 3. There was no significant difference when ISQ values obtained from the OSSTELL device were compared with the Penguin device for narrow diameter dental implants placed in dense bone blocks with osteotomies performed at 800 and 2000 rpm. ISQ values showed statistically significant higher values for OSSTELL compared to Penguin device. Conclusion: The OSSTELL and Penguin devices are reliable for the assessment of implant stability in dense artificial bone. Implant design and site‐DS does not seem to have a significant impact of implant stability in artificial dense bone blocks. [ABSTRACT FROM AUTHOR]

Objectives: There is a need of more studies on whether low primary implant stability would negatively influence the success of implant therapy. Therefore, this retrospective study analyses outcomes of implants placed with low primary stability and factors that may be related to implant failures. Material and methods: This retrospective study included 156 patients, restored with 169 implants that presented manual rotation within an observed follow‐up time of a minimum of 34 days and a maximum of 9.28 years. Descriptive statistics, survival analyses (life tables and Kaplan–Meier estimates) and radiographic assessment based on marginal bone level measurements were performed. This original study was adherent to STROBE guidelines. Results: Seven implants failed in seven patients, rendering cumulative survival rates of 94.74% (95% CI: 89.11–97.50) and 94.33% (95% CI: 88.30–97.30) at implant and patient levels, respectively. Kaplan–Meier estimates showed implant loss was found only in advanced surgery group (7 implant loss in 82 implants) when compared with simple surgery group (no implant loss in 87 implants; p = 0.005). Conclusions: Within the limitations of this retrospective study, implant placement with low primary stability might not negatively affect either the survival rates or marginal bone level changes of implants provided that a protected and unloaded healing is guaranteed. [ABSTRACT FROM AUTHOR]

Background: Peri‐implant defect morphology has shown to potentially impact upon the reconstructive outcomes for the management of peri‐implantitis. Given the role that defect morphology plays upon the decision‐making in the treatment of peri‐implantitis, the present study aimed at assessing the morphology and severity of peri‐implantitis bone defects and to insight on the patient‐, implant‐ and site‐related variables associated to these. Material and Methods: A cone‐beam computed tomography study was carried out to classify peri‐implantitis defects according to the type of defect, number of remaining bony walls and severity according to the extension of vertical bone loss. Three major defect categories were proposed: class I—infraosseous; class II—horizontal; class III—combined of class I and II. These were then subclassified into: (a) dehiscence; (b) 2/3‐wall; and (c) circumferential—type defect. According to the severity the defects were further subclassified into: A: advanced; M: moderate; and S: slight. In addition, 20 site‐, implant‐, and patient‐related variables were analyzed by generalized estimating equations (GEEs) of multilevel logistic regression models. Results: Based on an a priori power calculation, 332 implants were screened in 47 peri‐implantitis patients. Of these, 158 peri‐implantitis implants were eligible. The most prevalent defect morphology type was class Ib (55%) followed by class Ia (16.5%), and class IIIb (13.9%). On the contrary, the less frequent defect was class II (1.9%). The most frequent degree of severity was M (50.6%) with S (10.1%) being the least prevalent. Buccal bone loss was significantly greater compared to the other bony walls in class I and class III defects. Age was associated with the type of defect. Age and smoking habit were associated with the morphology of the defects, while smoking habit, type of prosthesis and distance to adjacent implant were associated with the severity of the defects (vertical bone loss). Conclusion: Peri‐implantitis defects frequently course with an infraosseous component and often with buccal bone loss. Certain patient‐, implant‐, and site‐specific variables are related with defect morphology and severity. However, morphological patterns for peri‐implantitis bone defects could not be proven (NCT NCT03777449). [ABSTRACT FROM AUTHOR]

Background: Biological responses to different loading protocols during the bone healing phase in subjects with long time since edentulism, rehabilitated with narrow diameter implants (NDIs) to retain mandibular overdentures (MOs), are still unavailable. Objective: This randomized clinical trial compared the peri‐implant health, implant stability, and concentrations of pro‐ and anti‐inflammatory cytokines in the peri‐implant crevicular fluid (PICF) in mandibular edentulous patients under conventional (CL) and immediate loading (IML) during healing. Methodology: Twenty totally edentulous patients received two NDIs (2.9 × 10 mm, Facility NeoPoros) placed in mandible anterior region and were randomly assigned to two loading protocols: CL (n = 10) and IML (n = 10). The following clinical outcomes were evaluated 1, 2, 4, 8, and 12 weeks after surgery: (a) peri‐implant tissue health (gingival index‐GI, plaque index‐PI, calculus‐presence CP, probing depth‐PD, and bleeding on probing‐BOP); (b) implant stability quotient (ISQ); and (c) IL‐1β, IL‐6, IL‐10, and TNF‐α levels in the PICF analyzed by ELISA. Results: The CL group showed significantly higher CP scores at weeks 8 and 12. The IML group showed significantly higher GI from the first week onwards. The IML group presented significantly lower PD at all follow‐up times, and higher BOP rates than CL at week 12. The ISQ values of the CL group were higher than those of the IML group, except at week 4. The IML group released significantly more TNF‐α between weeks 1 and 4 and more IL‐1β during week 4‐12, while releasing less IL‐6 until week 8, mainly at week 2 (−47.6%). The release of IL‐10 was similar for both groups and increased progressively over time. At week 12, the IML group released 45.74% more IL‐10 than the CL group. The survival rates were 95% and 90% for CL and IML, respectively. Conclusion: The IML group presented more favorable PD at all evaluation times; the differences between the other clinical parameters were less systematic. The implant stability and the inflammatory marker concentrations were more stable in the CL group. [ABSTRACT FROM AUTHOR]

Background: Given the fact that most patients are not regular compliers in supportive peri-implant maintenance programs, it is of interest to examine the significance of the peri-implant soft tissue characteristics in relationship to the onset of peri-implant diseases.Methods: Based on an a priori statistical power calculation, a cross-sectional study was conducted on erratic peri-implant maintenance compliers (<2 times/year) to examine the significance of keratinized mucosa (KM) and gingival tissue (KT) on peri-implant and adjacent periodontal conditions in implants restored ≥3 years. Seven clinical parameters were recorded around implants and the adjacent buccal sites. Radiographic assessment was performed using periapical X-rays. In addition, a visual analog scale (VAS) was used to evaluate the impact of KM upon brushing comfort. The case definition used for peri-implant diseases was in accordance with the 2017 World Workshop on the classification of periodontal and peri-implant diseases and conditions.Results: Overall, 37 patients with 45 edentulous gaps restored with 66 implants and 90 adjacent teeth were analyzed. On comparing a KM band of <2 mm versus ≥2 mm, with the exception of suppuration (P = 0.6), all the clinical and radiographic parameters were significantly increased when the KM band was <2 mm (P < 0.001). A significant correlation was observed between KM and KT (r = 0.55), though a lack of KM did not condition a lack of KT. In the presence of peri-implantitis, only bleeding on probing at the adjacent dentate sites was identified to be increased.Conclusions: The presence of <2 mm of KM around dental implants in erratic maintenance compliers seems to be associated with peri-implant diseases. The lack of KM constitutes a site-specific phenomenon independent of the keratinized tissue present in the adjacent dentition (NCT03501537). [ABSTRACT FROM AUTHOR]

Purpose: To assess the difference in the evolution of implant stability values, determined by resonance frequency analysis (RFA), between two groups of implants subjected to two different loading protocols: immediate and delayed. Materials and Methods: A retrospective clinical study was conducted, including a total of 93 implants placed in 38 patients. All implants corresponded to one of two models of the Klockner Implant System (Essential Cone and Vega) and were divided into two groups according to the loading protocol adopted: delayed loading in group A (>10 weeks) and immediate loading in group B (<48 hours). Implant stability was measured four times throughout the study period with a Penguin RFA device: implant placement (T0), definitive loading (T1), 6 months after loading (T2), and 12 months after loading (T3). Results: Implant stability quotient (ISQ) values showed a statistically significant increase in both groups after loading. In group A, the greatest increase in stability occurred between T1 and T2, whereas in group B, the greatest increase occurred between T0 and T1, coinciding in both cases with the period in which the implants were subjected to prosthetic loading. Conclusions: The functional loading of implants increases their stability, as measured in ISQ values by RFA. Increases in ISQ values are greater during the months immediately following loading, which shows that immediate or early loading protocols are not only possible but can also be beneficial. [ABSTRACT FROM AUTHOR]

Background: It is unknown whether it is possible to measure implant stability with polyetheretherketone (PEEK) healing abutments using electronic percussive testing (EPT). Purpose: To investigate the reliability of the percussive test values (PTVs) measured with PEEK healing abutments and to compare them with the PTVs measured with titanium healing abutments. Material and Methods: Thirty dental implants were inserted into the fresh pelvis belonging to a cow. Titanium healing abutments (2 and 5 mm), PEEK healing abutments (5 mm), and prepable standard titanium abutments (5 mm) were screwed to the implants, respectively, and PTVs were measured by two examiners using a wireless EPT device. Differences in PTVs between different dental implant components were evaluated using Friedman's test with post hoc Wilcoxon signed‐rank test and Bonferroni correction. Inter and intra‐observer reliabilities were detected using interclass correlation coefficients (ICCs) Results: The mean PTVs obtained using the PEEK healing abutments were significantly higher than the mean PTVs obtained using the other abutments for both examiners (P < .01). The ICCs for intra‐observer reliability were detected as poor for PEEK healing abutments; and excellent for the other abutment types for both examiners. The ICCs for the inter‐observer reliability between the two examiners were poor (0.25) for PEEK healing abutments, and excellent for the 2 and 5 mm titanium healing abutments and for standard abutments (0.82, 0.84 and 0.93, respectively). Conclusion: Within the limitations of this in vitro study, it may be concluded that EPT measurements should be avoided using PEEK healing abutments because of the poor reliability. [ABSTRACT FROM AUTHOR]

Background: Lack of consensus on the clinical parameters of peri-implantitis may complicate accurate diagnosis of the disorder. Furthermore, the lack of reliable estimates of the diagnostic capacity of the clinical endpoints precludes the definition of an effective treatment protocol for peri-implantitis. The present canine study assesses the diagnostic accuracy of the clinical parameters for monitoring the peri-implant tissues in a controlled ligature-induced peri-implantitis model followed by a spontaneous progression phase.Methods: Six beagle dogs were followed-up on during three episodes of ligature-induced peri-implantitis and a further episode of spontaneous progression. Probing depth (PD), bleeding on probing (BOP), mucosal recession (MR), and suppuration (SUP) were recorded at four sites per implant and at four study timepoints. Moreover, the implant mucosal index (IMI) was calculated at implant level. Marginal bone loss (MBL) was determined using computed tomography at four sites per implant. A linear regression model was used to estimate clinical and radiological parameters during peri-implantitis progression.Results: Progressive peri-implant bone loss is characterized by an increase in PD, more profuse BOP, MR, and SUP in advanced cases (p < 0.001). However, even in the presence of severe bone loss, SUP was not a common finding, with an incidence of approximately 10% at the last timepoint. These clinical parameters were significantly correlated to MBL at most of the timepoints. The IMI, in turn, showed a positive correlation to MBL and the peri-implant inflammatory signs (r = 0.39; p < 0.001), with a tendency to exhibit higher scores during ligature-induced peri-implantitis, followed by a slight decrease during the spontaneous progression period.Conclusion: The clinical features of peri-implantitis and spontaneous progression of the disorder may facilitate an accurate monitoring of peri-implant pathologic bone loss. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the effect of surface functionalization with bioactive glass BSF18 on the osseointegration of sandblasted and dual acid‐etched surface (AE) implants. Methods and Materials: Forty Morse taper implants with an AE surface as controls (C) or with an AE surface functionalized with BSF18 (BF) were placed in the mandibles of 10 beagles. Implants were analyzed after 2 and 4 weeks of healing. Implant stability quotient (ISQ) values were registered immediately after installation and prior to sacrifice. Samples were analyzed for bone‐to‐implant contact (BIC) and bone density (BD). The characterization of BF implants included surface roughness analysis with atomic force microscopy and contact angle (CA) analysis to evaluate wettability. Data were analyzed using two‐way ANOVA followed by Tukey's test (p < 0.05). Results: Surface roughness was not affected by BF treatment. CA was lower in the BF group compared to the C group. No significant difference was observed in ISQ values between surfaces (p = 0,231), irrespective of time. Significantly higher ISQ values were observed for both implants after 4 weeks when compared with baseline (p = 0.04). Significantly higher BIC (p = 0.011) and BD (p = 0.025) values were observed for the BF compared to the C group at 2 weeks. Significantly higher BIC (p = 0.030) and BD (p = 0.015) values for the C group were observed at 4 weeks compared to 2 weeks. No significant difference was observed in the BF group between 2 and 4 weeks. Conclusions: Implant functionalization with BSF18 improved the wettability of the implant surface; enhancing BIC and BD at 2 weeks. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the impact of progressive bone loss in an experimental peri‐implantitis model in the dog upon the implant stability quotient (ISQ) measured in the course of induced and spontaneous conditions of disease, and to evaluate the association between the clinical parameters and ISQ. Materials and Methods: Seventy‐two implants were placed in 12 Beagle dogs. Of these, 36 implants in six dogs were assessed during ligature‐induced peri‐implantitis (three timepoints) and at one timepoint following a period of spontaneous progression. The ISQ was recorded using resonance frequency analysis (RFA). Furthermore, the clinical peri‐implant parameters were registered at four sites per implant at each timepoint. Marginal bone loss (MBL) was determined using computed tomography at four sites per implant and bone‐to‐implant contact (BIC) was assessed from histological samples. A linear regression model was estimated by generalized estimation equations (GEEs) in order to study the MBL‐ISQ values at each measurement timepoint. Pearson's correlation test was applied. Results: None of the implants failed during the study period. At implant level, a strong negative correlation was found for all timepoints between ISQ and MBL (r = −0.58; p < 0.001). Accordingly, as follow‐up progressed, lower ISQ and higher MBL values were observed. A prediction of MBL depending on the ISQ values and timepoints showed a decrease in one ISQ unit to be related to ~1 mm of MBL. Likewise, a statistically significant correlation was found between BIC and ISQ evaluated after spontaneous chronification of peri‐implantitis (r = 0.34; p = 0.04). Nevertheless, the ISQ values failed to correlate to any of the clinical parameters recorded. Conclusion: Resonance frequency analysis seems accurate in diagnosing progressive bone loss, as a statistically significant decrease in ISQ was recorded in the course of peri‐implant disease. Nevertheless, the clinical relevance of this observation as a diagnostic tool is debatable, since implant stability remains high. [ABSTRACT FROM AUTHOR]

Background: Despite accumulating evidence for the longitudinal stability of the marginal bone level around an implant, there is limited evidence of predisposing risk factors for marginal bone loss based on some implants in a relatively large patient population. Purpose: The aim of this study was to retrospectively determine the marginal bone loss around Straumann tissue‐level dental implants during follow‐up periods among which the maximum lasts up to 10 years, as well as the predisposing risk factors for peri‐implant marginal bone loss. Materials and Methods: This study analyzed 1692 Straumann tissue‐level dental implants in 881 patients, and relevant data were collected. The peri‐implant marginal bone level was measured on periodic radiographs, and the changes in bone level were analyzed cumulatively from surgery until up to 10 years later. The log‐rank test was used to select candidate critical risk factors for marginal bone loss, and multivariate analysis using Cox regression with the shared frailty model was performed. Results: The overall peri‐implant bone loss was 0.07 ± 0.21mm, 0.09 ± 0.26mm, 0.14 ± 0.41mm, and 0.17 ± 0.45mm at 3, 5, 7, and 9 years, respectively. Only 14 implants showed pathologic marginal bone loss exceeding 2mm during the follow‐up period. While 2 implants were removed with continuous progressive marginal bone loss, 5 of the 14 implants showed early bone loss exceeding 1mm within the first year but then subsequently tended to show a stable marginal bone level. In the other seven implants, bone loss started after the first year and progressed continuously. Multivariate analysis revealed that diameter of the implant affected the peri‐implant marginal bone loss. Conclusions: Straumann tissue‐level dental implants showed only slight peri‐implant marginal bone loss, with a very low incidence of pathologic marginal bone loss exceeding 2mm. [ABSTRACT FROM AUTHOR]

Abstract: Background: Micro‐CT is a high‐resolution, non‐invasive, and non‐destructive imaging technique, currently acknowledged as a gold standard modality for assessing quantitatively and objectively dental morphology and bone microarchitecture parameters. Purpose: The aim of this study was to analyze critical dental and periodontal measurements characterizing the mandibular (MandFM) and maxillary (MaxFM) first molar architecture, as well as the corresponding bony socket, using micro‐CT. Materials and Methods: Thirty‐eight human dried skulls (22‐76 years) were scanned to enable the virtual analysis of 61 first molars. Depending on the type of measurement, the parameters were recorded on two‐dimensional sections or directly on three‐dimensional models. Tooth morphology was described by four aspects (e.g., tooth width, trunk length, root length, and root span), while the socket architecture was assessed by buccal plate thicknesses and bone density measurements. Results: Minimum, maximum, and mean distances as well as cortical and trabecular bone densities were recorded in MandFM and MaxFM. It is noteworthy that the buccal plate thickness was found to be less than 1 mm in more than 55% of cases in MaxFM, whereas only in 20.8% of cases in MandFM (and even 0% at two sites). A wide range of bone densities was observed and the comparison between MandFM and MaxFM did not show a significant difference. Furthermore, cortical densities were negatively correlated with aging, while trabecular densities were not influenced. Conclusions: Using micro‐CT, three‐dimensional aspects of the human first molar morphology and microstructural parameters of the surrounding bone were evaluated in the mandible and in the maxilla. These comprehensive measurements and their correlation with aging may be of great importance for the use of immediate implant placement in molar extraction sockets and thus the potential long‐term success of this treatment modality. [ABSTRACT FROM AUTHOR]

Abstract: Background: Narrow diameter implants (NDI) are recommended to retain mandibular overdentures (MOs) in cases of limited bone thickness. It is necessary to evaluate the clinical behavior of NDI as MO retainers connected to a new screwless locking taper abutments, their predictability and maintenance problems. Objectives: To evaluate the peri‐implant tissue behavior around NDI and the performance of locking taper stud abutments as MO retainers. Methodology: Thirty patients (average age of 67.5 years) received 2 NDI implants (2.9 × 10 mm) loaded after 12 weeks using Equator stud attachments. The plaque index (PI), calculus index (CI), gingival index (GI), probing depth (PD), bleeding on probing (BOP), and implant stability quotient (ISQ) were monitored during osseointegration at 0, 4, 8, and 12 weeks and postloading at 24, 48, and 60 weeks. The marginal bone level (MBL) and bone level changes (BLC) were determined at baseline and 60 weeks. Results: The cumulative success rate was 83.3%. The PI oscillated in the first 24 weeks and decreased from 48 weeks onward, while the CI score showed significantly higher values at week 8 (22%). The GI also peaked at week 8 (18.6%) and decreased from week 12 onward. The PD decreased gradually over time, but no significant differences were found between weeks 8 and 12. The ISQ decreased significantly between 0 and 12 weeks. After MO loading, the ISQ values increased linearly and significantly between 12 and 24, 24 and 48, and 48 and 60 weeks and reached values similar to the primary stability after 60 weeks [56.1(42.0‐65.3)]. No significant MBL was observed at 60 weeks, with an average BLC of −0.06 ± 0.64 mm. Conclusion: NDI connected to locking taper Equator attachments showed a stable clinical behavior as an MO retainer for edentulous patients with clinical mandibular atrophy. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to analyze and compare the topographical, chemical, and osseointegration characteristics of a sandblasted acid‐etched surface (SLA group), a sandblasted thermally oxidized surface (SO group), and a surface chemically modified by hydrofluoric (HF) acid (SOF group). Materials and methods: Following the preparation and characterization of the relevant surfaces, 90 implants (30 for each group) were placed on the pelvic bone of six sheep. Resonance frequency analysis (RFA), insertion (ITV), removal torque value (RTV), and histomorphometric analyses (BIC%) were performed after three and 8 weeks of healing. The results were analyzed by nonparametric tests (p < 0.05). Results: The roughness value (Ra) in the SOF group was significantly lower than the SLA and the SO group (p = 0.136, p < 0.001, respectively). This resulted in a substantially inferior ITV 14.83 N/cm (SD: 4.04) than those achieved in the SLA and SO groups (19.50 (SD: 6.07) and 20.17 N/cm (SD: 8.95), respectively; p = 0.001). A statistically significant change in the RFA from the baseline (47.36 ISQ, SD: 6.93) to the 3rd week (62.56 ISQ, SD: 5.29) was observed in the SOF group only (p = 0.008). The highest postplacement RFA and RTV values were measured from the SLA group (61.11 ISQ, SD: 7.51 and 78.22 N/cm, SD: 28.73). The early‐term (3rd week) BIC% was highest in the SO group (39.93%, SD: 16.14). After 8 weeks, the differences in BIC% values were statistically not significant. Conclusions: Adjunct HF acid application on the thermally oxidized surface did not provide an additional benefit compared to the sandblasted and acid‐etched surface (SLA group). [ABSTRACT FROM AUTHOR]

Objective: This study assessed the bone formation around titanium surface incorporating the calcium–magnesium (CaMg) deposited by blasted in rabbit tibia bone to determine whether this surface would further enhance bone healing compared with commercially available implant surface. Material and methods: The deposition of CaMg on the titanium SLA surface were obtained by blasting formed the experimental group (EX group), while implants with traditional SLA surface were used as control group (CO group), in this study. Fifty cylindrical threaded implants with a length of 8 mm were used (P = 25 per group). Five implants of each group were used to surface characterization by scanning electron microscopy, energy dispersive spectrometry, and optical profilometry. Ten New Zealand white rabbits received 40 implants (n = 20 per group). Resonance frequency analysis was performed three times (0, 4, and 6 weeks). Histomorphometric analysis was performed 4 and 6 weeks after implantation. Statistical significance was set at P < 0.05. Results: Blasted CaMg deposition on SLA implant surface displayed almost identical surface morphologies and R(a) values at the micron scale. In comparing the implant stability quotient at the three time points, highly significant statistic differences were found (P < 0.001). Histomorphological analysis showed higher degrees of bone organization in the samples of test implant surfaces at both implantation times. Conclusion: Within the limitations of this study, the results indicate that the deposition of CaMg on the SLA titanium surface may be effective in enhancing the osseointegration of moderately rough grit‐blasted implants by increasing the degree of bone–implant contact. [ABSTRACT FROM AUTHOR]

Objectives To compare the peri-implant bone healing between TiZr implants with hydrophilic SLActive and hydrophobic SLA implant surface in patients receiving anticoagulants, to assess the implant survival and success rate, as well as to evaluate whether small-diameter TiZr implants could be used in patients on OAT in order to avoid augmentation procedures. Material and methods A total of 80 small-diameter tissue-level TiZr implants with SLActive and SLA surfaces were placed in 20 anticoagulated patients, following the 'split-mouth' study design. Implant stability was measured up to the third postoperative month by resonance frequency measurements ( RFA). One-year implant survival and success rate were evaluated. Results After one year, 100% implant survival and success rate were observed. A significant decrease in ISQ comparing to baseline values was noted in the SLActive group from the first postoperative week, and in the SLA group, from the 3rd week after the surgery. In both groups, a statistically significant decline in ISQ was observed between second and third postoperative week. No significant differences in ISQ values between SLActive and SLA implants were noted, at any time point. Conclusions Titanium-zirconium small-diameter implants with SLActive and SLA surface predictably achieve and maintain adequate bone tissue integration in patients receiving anticoagulants. OAT appears to influence the bone healing events resulting in lower ISQ in the end of 3-month period in comparison with baseline values, although without compromising implant stability. [ABSTRACT FROM AUTHOR]

Background Implant-retained overdentures have become a standard option for the prosthetic treatment of the edentulous mandible in the elderly. Purpose This prospective study aimed to compare immediate and conventional loading of four interforaminal implants supporting a Locator-retained mandibular overdenture in elderly patients regarding implant survival, implant stability, and implant-related complications. Material and methods The study population comprised 20 completely edentulous patients (11 males) aged 60 years and older with severe mandible resorption. Each patient received four interforaminal implants (Neoss Ltd., Harrogate, UK). Following randomization, implants were loaded either immediately after dental implant surgery or 3 months after implant placement with the Locator-abutment system. At follow-up visits 3, 6 12, 24, and 36 months after loading, implant stability was evaluated with Periotest and Ostell. Results Twenty patients received 80 implants. In eight patients, 32 implants were loaded immediately. Two patients had to be switched from the immediate to the conventional loading group due to insufficient primary stability (≤30 Ncm). Implant survival was similar in both groups after 36 months. No implant was lost. Decreasing Periotest, and accordingly, increasing Ostell measurements indicated adequate osseointegration in both groups. The course of treatment was not significantly different in the two groups. There were comparable incidences of postoperative complaints like swelling, hematoma, or wound dehiscence, as well as need for prosthetic treatment due to abutment loosening or occlusal discrepancies. Incidence of pressure marks and number of patient visits were significantly higher in the conventional loading group. Conclusion With sufficient primary stability, immediate loading of four interforaminal implants in the edentulous mandible might be the preferential choice in the elderly, reducing total treatment time, and number of patient visits. [ABSTRACT FROM AUTHOR]

Background Chemical modifications of the dental implant surface that improve the wettability result in a faster and better osseointegration. Purpose The aim of this randomized clinical trial was to evaluate the implant stability quotient (ISQ) of implants with similar designs, treated with 2 surfaces, sandblasted acid-etched (SAE) and hydrophilic SAE, within the initial 16 weeks of healing. Material and methods A total of 64 implants (32 SAE-control group and 32 modified SAE-test group) with the same design, length, and diameter (conical and compressive, 4.3 × 10 mm) were inserted into the posterior maxillae of 21 patients partially edentulous. The ISQ values were collected at post-surgery (T0), 1 week (T1), 2 weeks (T2), 3 weeks (T3), 5 weeks (T4), 8 weeks (T5), 12 weeks (T6), and 16 weeks (T7). Results None of the implants failed. Test group presented ISQ values higher than the control group (ANOVA- P < .01) from T5 to T7. When comparing groups regarding the amount of time required to achieve ISQ ≥ 70 as a reference, there was a statistically significant difference (cox regression- P < .01), and a hazard ratio of 2.24 (CI 1.62-3.11). At the 1-year follow-up, there was a drop out of 1 patient, and 2 implants were no longer evaluated. Survival rate for both groups was 100% at the 1-year follow-up. Conclusions The current study suggests that implants with hydrophilic surface (modified SAE) integrate faster than implants with SAE surface. The stability gain of the test group was 2.24 times faster than the control group after 5 weeks of evaluation at the posterior region of the edentulous maxillae. [ABSTRACT FROM AUTHOR]

Background Companies affirm that tapered implants show adequate initial stability, while their installation in the lower arch is uncommon in clinical practice. Purpose To compare the clinical outcomes of tapered and cylindrical implants and to study their effect on bone site characteristics and peri-implant health during healing. Materials and Methods The implant site dimensions were assessed by linear measurements using CBCT prior to the installation of 40 implants in the posterior mandible (20 tapered and 20 cylindrical). The bone type was registered during drilling via the surgeon's tactile perception, following the classification of Lekholm and Zarb. Primary stability (PS) was determined by the insertion torque (IT) and the implant stability quotient (ISQ). Secondary stability (SS) and the peri-implant health was monitored for 3 months through the visible plaque index (VPI), the peri-implant inflammation (PI), the probing depth index (PDI), and the gingival bleeding index (GBI). Significant differences were investigated with t-tests for independent samples, chi-square tests or Fisher's exact test. Pearson's correlation test was used to investigate the relationship between the bone site characteristics and PS (IT and ISQ), as well as the relationships between IT and ISQ for each implant type. Results Tapered and cylindrical implants showed no significant differences for any outcome variable ( P > .05). A significant decrease in ISQ was observed after 7 days of healing ( P = .0002), followed by a gradual increase beginning at 21 days ( P = .0010) until the last follow-up time at 90 days ( P = .0319). The cortical height was correlated with IT; while medullary bone dimensions were correlated with the PS as evidenced by the ISQ values. The insertion torque was significantly correlated with the PS only for the cylindrical dental implants. Conclusions Tapered and cylindrical implants have similar biological behavior during the healing process. Bone site characteristics can influence insertion torque and implant stability. [ABSTRACT FROM AUTHOR]

Background Clinical conclusions in studying the stability and osseointegration of mandibular implants positioned using the bone expansion techniques are conflicting and limited. Purpose The objective was to examine the implant stability quotient (ISQ) values of mandibular posterior dental implants with 4.1 mm diameter that inserted with osteotome bone expansion technique versus conventional drilling technique during a 12-week observation period. Materials and Methods Twenty-four implants with 4.1mm diameter in 18 patients were included. Twelve implants in 10 patients were positioned using osteotome bone expansion technique, and 12 fixtures in 9 patients were installed using the conventional drilling technique. The ISQ values of a 3.3 mm diameter implant was measured at recipient sites (ISQb) before final drilling or expansion technique to standardize the increased ISQ value of 4.1 mm diameter implants. The ISQ values at Weeks 0, 1, 2, 3, 4, 6, 8, 10, and 12 post-surgery were recorded. Data were analyzed by Wilcoxon rank sum test, repeated measure ANOVA, and Fisher Lest Significant Difference test. Results Calibrated according to a 3.3-mm-diameter implant, bone expansion technique was adopted for the sites with ISQ≦65 bone density, and the areas with ISQ >65 bone condition were treated with conventional drilling technique ( p =.038). Both groups presented a similar healing pattern and a comparable ISQ reading from Week 0 to Week 12 ( p > .05) for 4.1 mm diameter implants. However, bone expansion technique could enhance more stability when the ISQ values were calibrated by 3.3 mm diameter implant ( p < .05). Conclusions Bone expansion technique substantially increased more ISQ values from primary stability and achieved comparable primary and secondary stabilities with the conventional technique. Both groups reached a stability plateaus at Week 10. [ABSTRACT FROM AUTHOR]

Purpose The present study aimed to measure the implant stability quotient (ISQ) values at three different time points after surgical procedures and crestal bone behavior in multiple implants (two or more) installed simultaneously with the bone splitting technique. Materials and Methods For this study, 45 patients with different edentulous areas in the maxilla were selected, and a total of 114 dental implants were installed. Implant stability was measured by resonance frequency analysis immediately following implant placement to assess immediate stability (time 1) and stability at 90 days (time 2), and 150 days (time 3). Crestal bone height was measured in peri-apical radiographs at 90 and 150 days after implantation in relation to each implant shoulder, given that the implants were installed at the level of the crestal bone. Results Six implants were not osseointegrated. Overall, the means and standard deviations of the ISQ values were 60.3 ± 4.94 (95% confidence interval [CI], 44-69) at baseline, 66.6 ± 5.28 (95% CI, 49-75) at 90 days, and 72.1 ± 4.28 (95% CI, 59-79) at 150 days ( p < 0.0001). The mean marginal bone loss of the implants was 1.11 ± 0.61 mm on the mesial side and 1.17 ± 0.61 mm on the distal side at time 2, and 1.73 ± 0.68 mm on the mesial side and 1.79 ± 0.70 mm on the distal side at time 3. A strong positive correlation between implant stability and bone loss was detected ( p < 0.0001). Conclusions Within the limits of this study, the bone splitting technique with simultaneous implant installation exhibited a good success rate with respect to the osseointegration index but requires attention with respect to crestal bone behavior. [ABSTRACT FROM AUTHOR]

Purpose To present a classification and assess the presence and degree of cortication of the sinus floor utilizing Computerized Tomography (CT) scan images. Materials and Methods One hundred CT scans, of patient who required a sinus augmentation procedure (SAP), were evaluated and classified according to the Type of sinus floor cortication (SFC). Type 1: sinus floor showing similar or higher density than the surrounding cortical areas. Type 2: sinus floor showing less density than the surrounding cortical areas. Type 3: sinus floor showing no cortical bone. Type 4: sinus floor showing the fusion of sinus floor bone and native crestal bone. Results The SFC were present in 31, 41, 18, and 10 cases in Type 1, 2, 3, and 4, respectively. Conclusions This classification based on the level of cortication of the sinus floor is clinically useful as a method of determining if the dental implant can be placed simultaneously or not with the SAP, or can be placed even without a SAP. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate the influence of different bone tissue characteristics of implant sites on changes in marginal bone level and implant stability over time. Material and methods One hundred and one implants were inserted in 41 patients. Cortical bone thickness of the alveolar ridge was measured on computed tomography ( CT) images. Histomorphometric and microtomographic analyses (micro CT) were performed in bone specimens obtained by using a trephine bur, at first drilling. Implant stability quotient ( ISQ) measured by resonance frequency analysis ( RFA) was registered at implant insertion. Implant stability quotient was measured also at the stages of uncovering, loading and at the 1-year follow-up, when standardized periapical radiographs were taken to measure the marginal bone level ( MBL). Descriptive statistics, Spearman's rho correlation and multiple linear regression were used for data analysis ( P < 0.05). Results Comparison between groups of higher and lower values of ISQ changes and between groups of higher and lower values of MBL changes revealed no differences in histomorphometric and microtomographic parameters, according to non-parametric comparison tests, ( P > 0.05). Bivariate correlation also showed no association among these microstructural parameters and the outcomes evaluated. There was no correlation between cortical thickness and MBL changes ( r = −0.029; P = 0.832) and between cortical thickness and ISQ changes ( r = 0.145; P = 0.292). Conclusion Microstructural bone characteristics of implant sites have no effect on changes in marginal bone level and implant stability as measured by RFA. Bone morphology cannot predict implant treatment success over time. [ABSTRACT FROM AUTHOR]

Objectives When implants are inserted, the initial implant stability is dependent on the mechanical stability. To increase the initial stability, it was hypothesized that bone condensation implants will enhance the mechanical stability initially and that the moderately rough surface will further contribute to the secondary stability by enhanced osseointegration. It was further hypothesized that as the healing progresses the difference in removal torque will diminish. In addition, a 3D model was developed to simulate the interfacial shear strength. This was converted to a theoretical removal torque that was compared to the removal torque obtained in vivo. Material and methods Condensation implants, inducing bone strains of 0.015, were installed into the left tibia of 24 rabbits. Non-condensation implants were installed into the right tibia. All implants had a moderately rough surface. The implants had an implantation time of 7, 28, or 84 days before the removal torque was measured. The interfacial shear strength at different healing time was estimated by the means of finite element method. Results At 7 days of healing, the condensation implant had an increased removal torque compared to the non-bone-condensation implant. At 28 and 84 days of healing, there was no difference in removal torque. The simulated interfacial shear strength ratios of bone condensation implants at different implantation time were in line with the in vivo data. Conclusions Moderately rough implants that initially induce bone strain during installation have increased stability during the early healing period. In addition, the finite element method may be used to evaluate differences in interlocking capacity. [ABSTRACT FROM AUTHOR]

Purpose To evaluate stability and success rate of hydrophilic nanostructured implants placed via osteotome sinus floor elevation ( OSFE) without grafting material or using β-tricalcium phosphate (β- TCP), deproteinized bovine bone ( DBB), or their combination, and also to assess three-dimensional volumetric stability of endo-sinus bone gained in the aforementioned conditions. Materials and Methods OSFE with simultaneous implant placement (10-mm long SLActive- BL®, Straumann, Basel, Switzerland) was performed. Grafting materials were randomly allocated to implant sites, whereas one site was left without graft. Implant stability was measured by resonance frequency analysis over 6 months. Implant success was evaluated after 2 years of loading. Volume of new endo-sinus bone was calculated from CBCT images using 3D S licer® software. Results A total of 180 implants were inserted into posterior maxilla of 45 patients with 6.59 ± 0.45 mm of residual bone height, and all remained successful after 2 years. Implant stability steadily increased during healing, without significant difference between groups ( p = .658). After 2 years, endo-sinus bone significantly shrank ( p < .001) in all groups ( DBB:66.34%; β- TCP:61.44%; new bone formed from coagulum: 53.02%; β- TCP + DBB:33.47%). Conclusions Endo-sinus bone gained after OSFE inevitably and significantly shrinks regardless of whether grafting material is applied or not. Grafting material offers no significant advantage to stability nor clinical success of hydrophilic and nanostructured implants placed simultaneously with OSFE. [ABSTRACT FROM AUTHOR]

Background: Short dental implants can be an alternative to bone augmentation procedures at sites of reduced alveolar bone. Most studies on short implants are retrospective or multicentre reports that lack controlled and consistent comparison between different systems. This study aimed to compare clinical and radiographic outcomes of short implants in two different systems in the posterior mandible.Methods: Twenty patients with two adjacent missing posterior teeth were recruited. Patients were assigned equally and randomly into two groups; Bicon(®) (6 or 8 mm) and Ankylos(®) (8 mm) implants. A two-stage surgical approach and single crowns were used for implant placement and loading. Outcomes included peri-implant clinical parameters, implant stability (Periotest values; PTVs) and peri-implant bone changes, which were assessed at baseline, 2, 6 and 12 months post-loading.Results: No implant loss was encountered up to 12 months post-loading. No significant difference in the clinical or radiographic parameters was observed except for PTVs (p < 0.05) that was lower in Ankylos(®) implants.Conclusions: The use of short dental implants was associated with excellent 12 months clinical and radiographic outcomes. Ankylos(®) and Bicon(®) implants demonstrated similar peri-implant soft tissue and alveolar bone changes. However, Ankylos(®) implants demonstrated better implant stability at all evaluation intervals. [ABSTRACT FROM AUTHOR]

Objectives The present study measured implant stability quotient (ISQ) values at three different time points after surgical procedures to compare whether the stability values differed between implants placed in fresh extraction sockets versus healed alveolar sites. Materials and methods To measure implant stability, resonance frequency analysis (RFA) was performed in 77 patients (53 women, 24 men) with a total of 120 dental implants. These implants were divided into two groups: Group 1 included 60 implants in healed alveolar sites (22 in the maxilla, 38 in the mandible), and Group 2 included 60 implants in fresh sockets (41 in the maxilla, 19 in the mandible). Implant stability was measured immediately at implant placement (baseline), 90, and 150 days later. Statistical analysis was made using a multivariate regression linear model at implant level (α = 0.05). Results Overall, the means and standard deviations of the ISQ values were 62.7 ± 7.14 (95% confidence interval [CI], 39-88) at baseline, 70.0 ± 6.22 (95% CI, 46-88) at 90 days, and 73.4 ± 5.84 (95% CI, 58-88) at 150 days. In Group 1, the ISQs ranged between 64.3 ± 6.20 and 75.0 ± 5.69, while in Group 2, presented lower values that ranged between 61.2 ± 8.09 and 71.9 ± 5.99 ( P = 0.002). Anatomic location and times periods were the only identified variables with an influence on ISQ values at implant level ( P < 0.0001). Conclusions The stabilities of the implants placed in the fresh sockets and in healed sites exhibited similar evolutions in ISQ values and thus osseointegration; however, the implants in the healed alveolar sites exhibited superior values at all time points. [ABSTRACT FROM AUTHOR]

Purpose This retrospective investigation aimed to evaluate the effect of early moderate loading ( EML) on implant stability. Materials and Methods Following 6 weeks of conventional healing, 634 dental implants ( Ankylos®, Dentsply Implants, Mannheim, Germany) inserted in 247 patients were uncovered. Provisional restorations were placed in infra-occlusion in partially edentulous patients and in full occlusion in edentulous patients. Patients were instructed to consume a soft/liquid diet until final restorations were delivered after approximately 6 weeks. Periotest values ( PTVs) at the time of uncovering and after EML were assessed in order to calculate the change in PTV (Δ PTV). Improvement of the PTV was analyzed to account for dependencies between measurements on multiple implants of a single patient, along with other factors. Results No implant was lost during the EML. After a mean loading time of 3 years (±1.7 years), the implant survival rate was 98.74%. The PTV of 556 implants decreased (improved) over the course of the study. The Δ PTV was statistically significant ( p = .0001), and none of the factors analyzed appeared to influence it. Conclusions The EML of implants does not impair the implants' stability, as determined by Periotest. On the contrary, early moderate loading seems to be beneficial at compromised bone qualities. [ABSTRACT FROM AUTHOR]