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OBJECTIVES To evaluate the peri-implant marginal bone level for immediately loaded implants placed simultaneously in both fresh extraction sites (FES) and healed sites (HS) supporting a 4-implant supported mandibular fixed prosthesis (4-ISFMP) using the all-on-4 concept. MATERIAL AND METHODS A 5-year prospective study was conducted in 24 patients (96 implants) treated with 4-ISFMP including fifty-five implants inserted in FES and 41 implants in HS. At implant placement (baseline) and at the 1st , 3rd and 5th year follow-up examinations, peri-implant marginal bone level was evaluated radiographically and compared between placement in FES and HS. Marginal bone loss was calculated as the difference of the marginal bone level evaluated at the follow-up periods. Additionally, implant and prosthesis survival rates as well as the presence of peri-implant mucositis (bleeding on probing+[BOP]) and peri-implantitis (BOP+ >2mm MBL) were evaluated. RESULTS 22/24 patients with 88/96 implants (dropout rate: 8.3%) were continually followed for 5 years (survival rate: 100%). Radiographically measured marginal bone level differed significantly between FES and HS at implant placement (1.46±0.80mm vs. 0.60±0.70mm; p 0.99) and the 3- to 5-year period (p=0.082). At the 5-year follow-up evaluation, no implant/prosthesis failed (100% survival) and peri-implant mucositis and peri-implantitis were noted in 41.2% and 11.7% at patient level and in 17.6% and 4.5% at implant level, respectively. CONCLUSION Implants placed in FES showed a prolonged peri-implant remodelling process but provided for similar peri-implant marginal bone levels as implants placed in HS at the 5-year evaluation for immediately loaded 4-ISFMP.

OBJECTIVES To summarize the clinical performance of anodized implants connected to different prostheses design after immediate/early (IL) or conventional loading (CL) protocols. MATERIALS AND METHODS Seven databases were surveyed for randomized (RCTs) and non-randomized controlled clinical trials (CCTs). Studies comparing IL vs. CL protocol of anodized implants supporting single crown, fixed partial denture (FPD), full-arch fixed dental prosthesis (FDP), or overdenture were included. Risk-of-bias was evaluated using Cochrane Collaboration tools. Meta-analyses for different follow-up were analyzed, followed by heterogeneity source assessment and GRADE approach. The outcomes included implant survival rate, marginal bone loss (MBL), implant stability quotient (ISQ), probing depth (PD), plaque index (PI), and peri-implantitis prevalence. RESULTS From 24 eligible studies, 22 were included for quantitative evaluation. Most RCTs (58%, n = 11) and all the 5 CCTs had high and serious risk-of-bias, respectively. Overall, pooling all prosthesis design, no difference between IL vs. CL protocols was observed for all outcomes (p > .05). However, according to prosthesis type subgroups, CL reduced MBL for full-arch FDP (p

OBJECTIVES Comparing PES/WES scores, modified success rate, survival, success, buccal bone thickness and patient-reported outcomes of immediate dental implants placed in fresh alveolar sockets using a flap or a minimal split-thickness envelope flap (MSTEF). MATERIALS AND METHODS Implants following random assignment into a flap or MSTEF group were placed immediately in anterior and premolar areas. Guided bone regeneration and autogenous connective tissue graft were used in all cases. A temporary prosthesis was provided followed by the final prosthesis at 16-18 weeks. Success and survival rates together with radiographic buccal bone thickness and patient satisfaction were evaluated at 12-month post-loading. The aesthetic outcome was evaluated through the Pink (PES) and White (WES) Aesthetic Score by 8 blind clinicians of different training background and incorporated in modified success criteria. RESULTS 28 implants were placed on 28 patients. No statistically significant differences were noted in PES (10.54 control versus 10.80 test), WES scores (6.97 control versus 6.95 test) or success criteria including aesthetic parameters (modified success criteria) for the different specialty groups (Range 69%-92%). In addition, no statistically significant differences were noted in survival (100%), success (100%), buccal wall thickness between control (0.72 ± 0.22) and test group (0.92 ± 0.31) and patients' reported outcomes. CONCLUSIONS Immediate dental implant treatment with flap/ MSTEF provided similar mean PES/WES scores, modified success rate, survival, mean buccal bone levels and patients' satisfaction. However, aesthetic failures were common in both groups.

Objective This prospective study aims to assess the 5‐year clinical performance of implants with internal conical connection and platform‐switched abutments in the posterior mandible. Material and Methods Healthy adults missing at least two teeth in the posterior mandible and with a natural tooth mesial to the implant site received two or three adjacent implants. After a transmucosal healing period single crown restorations were cemented on platform‐switched abutments. Changes in marginal bone levels were investigated in standardized periapical radiographs from surgery and loading (baseline) to 60‐months post‐loading. Results Twenty‐four patients received 52 implants. Bone remodelling took place between surgery and loading (mean:‐0.5, SD:±0.4 mm). From loading to 60 months, there was a mean bone change of 0.27 (SD:±0.47 mm) which stabilized 24 months after prosthesis delivery (mean:0.2, SD:±0.46 mm). 71.7% of all implants presented bone preservation at 60 months irrespective of the initial insertion depth. Two implants were lost after 5 years and the success rate was 95.1%. Patient enquiry revealed high satisfaction. Conclusion Internal conical connection implants with platform‐switched abutments presented a high success rate and preservation of marginal bone levels at the implant shoulder after 5 years of loading.

OBJECTIVES To compare the clinical treatment outcomes of maxillary four-implant retained overdentures with either splinted (bar) attachments or non-splinted (ball) attachments. MATERIAL AND METHODS Forty participants who were dissatisfied with their existing conventional maxillary complete dentures were included in this randomized controlled trial. Six months after implant placement, a definitive prosthesis was inserted. Implant success, condition of peri-implant tissue, prosthodontic maintenance and complications, and patient satisfaction were assessed. Outcomes were recorded at baseline, prosthesis delivery, and at 3 and 12 months following prosthesis delivery, and a statistical analysis was performed. RESULTS Thirty-two of the forty patients completed the 1-year follow-up and had their treatment outcomes evaluated. The mean marginal bone loss after 1 year of loading was 0.34 ± 0.88 mm, and there were no significant differences between the two groups. Plaque index, gingival index and bleeding on probing were significantly higher in the bar group (p

Objectives The aim was to evaluate the peri-implant tissue levels over a 1-year period for implants connected to either convex or concave final abutments at the time of implant placement. Materials and methods In this randomized, double masked, controlled clinical study, twenty-eight patients with one missing maxillary premolar were allocated to receive one single implant with abutment of either convex (CX Group) or concave (CV Group) emergence shape. A block randomization sequence was used to allocate treatments. Opaque sealed randomization envelopes were used for allocation concealment. All implants received final abutments and interim crowns at implant placement and permanent crowns following 3 months. Clinical and radiographic data were collected at the time of implant placement (IP), final prosthesis delivery (PR), and 12 months following implant placement (FU-1). Results One patient from the CX Group (n = 13) dropped out from the study and for one patient from CV Group (n = 13), the implant failed to integrate. The mean change in peri-implant buccal mucosa position (MP) from IP to FU-1 was -0.76 ± 0.72 mm for CX Group and -0.69 ± 0.89 mm for CV Group (p = 0.8). The amount of bone remodeling above the implant platform from IP to FU-1 was -0.66 ± 0.46 mm for the CX Group and -0.24 ± 0.25 mm for the CV Group (p = 0.007). Buccal bone thickness was significantly correlated with the amount of buccal MP change from IP to FU-1 (r = 0.4, p = 0.038). Conclusion The study failed to support the hypothesis that abutment macro-design has an effect on peri-implant mucosa margin position changes over time.

Objective To assess the prostheses and implants survival rate and peri-implantitis rate in edentulous patients treated with full-arch screw-retained implant-supported fixed dental prostheses (FSIFDPs) and full-arch telescopic-retained implant-supported fixed dental prostheses (FTIFDPs) over an observation period of at least 5 years. Materials and methods From 2004 to 2012, 696 implants were inserted into 78 patients with 102 prostheses. The FSIFDP group comprised 31 patients (37 prostheses, 232 implants), whereas the FTIFDP group comprised 47 patients (65 prostheses, 464 implants). Prosthesis and implant estimated cumulative survival rates (ECSR) and estimated cumulative peri-implantitis rates (ECPR) were assessed. The follow-up period was 5-12 years. Kaplan-Meier survival curves with the log-rank test were used to evaluate outcomes. Results The 12-year prosthesis ECSR was 96.8% (95% CI: 79.2-99.5, 36/37 prostheses) in the FSIFDP group and 96.4% (95% CI: 86.3-99.1, 63/65 prostheses) in the FTIFDP group, whereas the 12-year implant ECSR was 99.5% (95% CI: 96.4-99.9, 231/232 implants) in the FSIFDP group and 98.7% (95% CI: 96.9-99.5, 459/464 implants) in the FTIFDP group. The 12-year ECPR at the prosthesis level was 12.8% (95% CI: 12.7-47.6, 4/37 prostheses) in the FSIFDP group and 12.8% (95% CI: 11.4-24.1, 6/65 prostheses) in the FTIFDP group. The 12-year ECPR at the implant level was 4.4% (95% CI: 4.3-23.0, 6/232 implants) in the FSIFDP group and 2.2% (95% CI: 2.0-12.3, 7/464 implants) in the FTIFDP group. Conclusion FTIFDPs have clinical results comparable to those of FSIFDPs. Therefore, FTIFDPs can be useful.

Objectives: The aim of the present publication was to report on the EAO Workshop group-4 discussions and consensus statements on the five reviews previously prepared. These reviews provided the scientific evidence on the effect of crown-to-implant ratio, on reconstructions with cantilevers in fully and partially edentulous patients, on biological and technical complications of tilted in comparison with straight implants, and on the effects of osseointegrated implants functioning in a residual dentition.Material and Methods: The group discussed, evaluated, corrected where deemed appropriate, and made recommendations to the authors regarding the following five reviews submitted: (a) Is there an effect of crown-to-implant ratio on implant treatment outcomes?; (b) Implant-supported cantilevered fixed dental rehabilitations in fully edentulous patients; (c) and in partially edentulous patients; (d) Biological and technical complications of tilted implants in comparison with straight implants supporting fixed dental prostheses; (e) What are the adverse effects of osseointegrated implants functioning among natural teeth of a residual dentition? Based on the five manuscripts and the discussion among the group as well as the plenum members, the major findings were summarized, consensus statements were formulated, clinical recommendations were proposed, and areas of future research were identified.Results: Crown-to-implant ratios ranging from 0.9 to 2.2 did not influence the occurrence of biological or technical complications also in single-tooth restorations. Reconstructions with cantilevers for the rehabilitation of fully and partially edentulous jaws showed high implant and reconstruction survival rates. In contrast, the rate of complications-in particular associated with veneering material-was high during the observation period of 5-10 years. The data reported were primarily derived from studies with high risk of bias. The data for single-implant reconstructions were small. There was no evidence that distally tilted implants were associated with higher failure rates and increased amounts of marginal bone loss. The data supporting these findings, however, were at high risk of bias and frequently incompletely reported. Frequent positional changes occurred between the natural teeth and the implant-supported restorations. These changes were more pronounced in younger individuals, and even though they were reduced with age, they still occurred in adult patients. Even though these changes were frequent, potential implications for the patient are unclear.Conclusions: The use of single-tooth restorations with crown-to-implant ratio in between 0.9 and 2.2 may be considered a viable treatment option. Multiunit reconstructions with cantilevers are a viable treatment option in fully and partially edentulous patients. Clinicians and patients should be aware, however, that complications are frequent and primarily related to resin material used for veneering. There is some evidence that tilting an implant does affect stability of the implant and the surrounding bone. Treatment options to tilted implants should carefully be considered, as the effect on soft tissues and on prosthesis behavior is poorly reported for tilted implants. Positional changes in the dentition in relation to implant-supported restorations occur frequently. The patient should be informed about the possible need for a treatment related to these changes in the long term.

Objective To evaluate the clinical and patient-reported outcome of all-ceramic zirconia implant supported fixed dental prostheses (FDPs) 5 years after implant installation. Materials and methods Thirteen patients were treated with two terminally placed one-piece zirconia implants for a three-unit FDP each. The FDPs consisted of a CAD/CAM-fabricated zirconia framework over-pressed with a fluor-apatite veneering ceramic and were adhesively cemented. Survival and success were assessed by applying modified US Public Health Service (USPHS) criteria and preparation of Kaplan-Meier (KM) plots. Alpha and Bravo ratings were accepted for success (among others including small area veneer chippings and occlusal roughness), whereas Charlie ratings allowing for intra-oral correction (e.g., polishing) were accepted for survival. Furthermore, patient-reported outcome measures (PROMs) were analyzed with the help of visual analogue scales (VAS). Wilcoxon matched-pairs signed-rank test (USPHS criteria) and linear mixed models (PROMs) were used to evaluate time effects on response variables. Results All patients were available 61.8 ± 1.1 months after implant installation (53.6 ± 3.1 months after final prosthesis insertion). FDP survival was 100%. Significant incidence of veneer chipping (p = .0096) and occlusal roughness (p = .0019) was observed. Charlie rated extent of both phenomena resulted in a KM success estimate of 38.5% (95% CI: 14.1%-62.8%; seven FDPs with obvious roughness, three of them with extended veneer chipping). Compared with the pre-treatment assessments (30%-81% of satisfaction), all surveys at prosthetic delivery showed significantly improved VAS scores (66%-93%; p ≤ .038), except for speech (p = .341). Concerning function, esthetics and self-esteem, no decrease in satisfaction could be observed until the end of follow-up (90%-96%; p ≥ .057), whereas perception of sense (92%) and speech (95%) increased over time (p ≤ .030). Occurrence of technical complications did not correlate with patient satisfaction. Conclusions Bi-layered FDPs made from zirconia/fluor-apatite highly satisfied patients but showed significant incidence of technical complications.

Objectives To compare clinical performance of a novel resorbable non-cross-linked collagen membrane (CXP) with a reference membrane (non-cross-linked resorbable membrane; BG) for simultaneous implant placement and guided bone regeneration (GBR) at dehisced single implant sites. Materials and methods Preliminary data from this randomized controlled trial were reported previously; this is the 12-month report. The primary outcome measure was defected height at 6 months post-GBR. Secondary outcomes included implant cumulative survival rate (CSR) and success rate since placement; bone level changes, pink esthetic score (PES), and patient satisfaction since definitive prosthesis delivery; patient quality of life since pretreatment; and the 1-year bleeding index. Non-parametric statistical analyses were performed. Results Among patients, 24 were treated with CXP and 25 with BG. The 1-year implant CSR and success rate were 100% (n = 42). Bone level change between definitive prosthetic delivery and 1 year was not significantly different between the CXP and BG groups (BG + 0.42 mm, CXP + 0.01 mm). The PES increased from 7.55 to 8.10 for the CXP group and from 6.48 to 7.48 for the BG group; 1-year bleeding indices were 0 (16 CXP, 18 BG) and 1 (4 CXP, 2 BG). Patient quality of life changed from an OHIP-14 score of 6.5 at pretreatment to 1.9 at 1 year. Overall satisfaction (visual analogue score) with function and esthetics was 9.9 and 9.7, respectively. Inter-group differences were not significant for assessed outcomes. No device-related adverse events were reported. Conclusions The use of CXP and BG for simultaneous implant placement and GBR at dehisced implant sites similarly reduced defect height and improved secondary measures, indicating non-inferiority.

Objectives The purpose of this study was to determine the improvement in masticatory performance and satisfaction with chewing ability in partially edentulous patients after treatment with an implant-supported fixed partial prosthesis (ISFPP). Material and methods This prospective study included 30 patients (mean age 59 years; 17 women) with unilateral posterior missing teeth treated with one-, two- or three-unit ISFPPs and 10 healthy individuals (mean age 36 years; 8 women) with complete natural dentition to establish the normal levels of mastication. Three variables were determined at baseline and at 3-months' follow-up in all participants: masticatory performance according to the median particle size (MPS) during freestyle mastication and unilateral mastication on each side, and satisfaction with chewing ability using a visual analog scale. Paired samples t test and Kruskal-Wallis test were used for intra-group and inter-group comparisons. Results The MPS following freestyle mastication decreased significantly at 3 months in both groups. Significant reductions of 21%, 30%, and 42% in the MPS were obtained from unilateral mastication on the treated side after treatment with 1, 2, or 3 restorative units, respectively. Three months after ISFPP, satisfaction with chewing ability improved by 40% in the treatment group. Conclusions Freestyle masticatory performance may improve slightly within three months of treatment with an ISFPP and may be similar to that of subjects with complete natural dentition. Patients may obtain a 21%-38% improvement in unilateral mastication on the treated side and a 26%-54% improvement in satisfaction with chewing ability.

Objectives: The aim of this RCT was to assess radiographically the effect of abutment height and depth of placement of platform-switched implants on interproximal peri-implant bone loss (IPBL) in patients with thin peri-implant mucosa. Material and Methods: Thirty-three patients received one prosthesis supported by two implants replacing at least two adjacent missing teeth (66 implants). Patients were randomly allocated and implant insertion depth adapted to abutment height groups (3 mm height group the implants were placed 2 mm subcrestally; 1 mm height group, equicrestally). Clinical and radiological measurements were performed at 3, 6 and 12 months after surgery. Interproximal bone-level changes were compared between treatment groups using repeated measures mixed ANOVA. The association between IPBL and categorical variables was also analyzed. Results: The mean IPBL in 1 mm abutment group was 0.76 ± 0.79 mm at 3 months, 0.92 ± 0.88 mm at 6 months, and 0.95 ± 0.88 mm at 12 months, while in the 3 mm abutment group was 0.06 ± 0.21, 0.07 ± 0.22 mm, and 0.12 ± 0.33 mm, respectively. Significant differences between both groups were observed at every time point. When the influence of patient characteristics and clinical variables was analyzed, no statistically significant differences were also observed. Conclusions: The use of long abutments, in combination with subcrestal implant position in sites with thin mucosa, led to lower IPBL in comparison with the use of short abutments.

Objectives The aim of this study was to assess the clinical outcomes of a nonsurgical treatment protocol for peri-implantitis and to evaluate the influence that some factors could have on the results of this treatment. Material and methods In this retrospective case series, patients with at least one implant with peri-implantitis, treated with a nonsurgical protocol and with a one-year follow-up, were included. Clinical parameters (probing depth, recession, bleeding, and/or suppuration on probing) were collected at baseline, 6 weeks, 3, 6, and 12 months. Radiographic bone levels were assessed in periapical radiographs taken at baseline and 12 months. An analysis of the factors significantly associated with marginal bone level changes was performed. Descriptive and analytic statistics were carried out at the patient and at the implant level, as well as a multiple linear regression analysis. Results Data from 37 patients with 70 implants were analyzed. There was a general and consistent improvement from baseline compared to all follow-up points in the clinical variables. A significant radiographic bone gain of 0.91 mm was observed. The factors significantly associated were baseline plaque index, sex, and age at patient level, and type of prosthesis and implant location at implant level. Conclusions Within the limitations of this study, this nonsurgical treatment protocol might be considered as a first treatment option for peri-implantitis. More studies are needed, with larger sample sizes and longer follow-ups, to confirm these outcomes and their long-term stability.

Objectives To investigate in which clinical situations a cantilever fixed implant supported restorations can be a treatment alternative and which complications are reported. Materials and methods Two operators screened the literature (MEDLINE, EMBASE) and performed a hand search on the main journals dealing with implantology and prosthetics until 31 December 2017. Only articles that considered cantilever implant fixed restorations with at least 10 patients and with a mean follow-up of at least 5 year were selected. The outcome variables were survival of implants and prosthesis, mechanical, technical and biological complications, marginal bone loss. The review was performed according to the PRISMA statements. Risk of bias assessment was evaluated. Failure and complication rates were analysed using random effect Poisson regression models to obtain summary estimate of 5- and 10-year survival and complication rates. Results A total of nine papers were selected for partially edentulous patients and reported high survival rate of the prosthesis. The estimated survival rate for 5-10 years was calculated to be 98.4% for the implants and 99.2% for the rehabilitations. Mechanical, technical and biological complications were reported with a cumulative 5-10 years complication rate of 28.66% and 26.57% for the patients and for the prosthesis, respectively. Two papers for single implant supporting 2-unit cantilever were not sufficient to draw conclusions. Conclusions There is evidence that cantilever can be successful treatment in partially edentulous patients. In two adjacent edentulous sites, data are not yet sufficient.

OBJECTIVES To evaluate prospectively the clinical and radiographic outcomes after ten years of short (6 mm) implants with a moderately rough surface supporting single crowns in the posterior region. MATERIAL AND METHODS Forty 6 mm modified sandblasted large-grit acid-etched (mod-SLA), soft tissue level implants were installed in the distal segments of 35 consecutive patients. After 6 weeks of healing, abutments were tightened, and single porcelain-fused-to-metal crowns were cemented. Implant survival, marginal bone loss, and clinical crown/implant ratio were evaluated at various time intervals up to 10 years after loading. RESULTS Two out of the 40 implants were lost before loading, one implant was lost after 7 years because of peri-implantitis. One patient with two implants died and was excluded from analysis. Two patients did not come at the 10-year follow-up and were considered as drop out (2 implants). The survival rate was 91.7% (n = 36). Thirty-three implants were available for marginal bone loss evaluation. A mean marginal bone loss after 10 years of function was 0.8 ± 0.7 mm. Between 5 and 10 years, the loss was 0.2 ± 0.4 mm. No technical complications were registered during the 10-year period. The clinical crown/implant ratio increased with time from 1.6 at the delivery of the prosthesis to 2.0 after 10 years of loading with no increase between 5 and 10 years. CONCLUSION Short (6 mm) implants with a moderately rough surface supporting single crowns in the posterior region and loaded after 6-7 weeks maintained full function for at least 10 years with low marginal bone resorption.

Objectives To examine the impact of adding a third midline implant with stud attachment to a mandibular two-implant overdenture on patient-oriented outcomes. Methods In this pre-post design clinical trial, following the standard procedures, mandibular two-implant overdentures of 17 edentulous individuals (61.9 ± 6.6 years) were converted to three-implant overdentures by adding a stud attachment to an unloaded midline implant. Patient-oriented outcomes included patient expectations and satisfaction with implant overdenture as well as willingness to pay the cost of conversion. Data were collected at baseline and at the 6-week follow-up using visual analog and binary scales as well as open-ended questions. Statistical analysis included descriptive statistics, Spearman's correlation, Fisher exact test, Mann-Whitney U test, and the exact sign test. Results After connecting the third midline implant to the mandibular two-implant overdenture, there was a statistically significant decrease in the anteroposterior movement (p = 0.005) as evaluated by clinicians. Moreover, study participants reported an increase in perceived stability of the overdenture (95% CI; 0.68-1.00, p = 0.002) and in their ability to speak (95% CI; 0.63-1.00, p = 0.008). The addition of a third implant met the expectations of 94% of patients in regard to lower denture stability, 100% for retention, and 82.4% for comfort. The mandibular three-implant overdenture increased patient general satisfaction over a short period of time, but this improvement was not statistically significant. About 80% of patients would recommend this type of prosthesis to their peers but only 47% of them would agree to pay a large increase in the cost of treatment compared to a two-implant overdenture. Conclusions The addition of a midline third implant to an existing mandibular two-implant overdenture resulted in several improved patient-reported outcomes.

Objectives To assess the rate of biologic complications and implant survival in edentulous patients treated with implant-supported fixed complete dental prostheses (IFCDPs) after a mean observation period of 5.2 years (range: 1-12 years). Materials and methods A single-visit clinical and radiographic examination was performed to assess types and rates of biologic complications with ceramic IFCDPs (Group 1) and metal-resin IFCDPs (Group 2). Results Of 457 rough surface dental implants supporting 71 IFCDPs (52 patients), six had failed, yielding an implant survival rate of 98.7% after a mean observation period of 5.2 years after definitive prosthesis insertion. The most frequent minor biologic complication was soft tissue recession (7.7% annual rate), inflammation under the IFCDP (7.4% annual rate), and peri-implant mucositis (6.3% annual rate). The most frequent major biologic complication was peri-implantitis (2.0% annual rate), in 46/457 implants (10.1%) supporting 19 IFCDPs and late implant failure (0.3% annual rate). The frequency of biologic complications was not statistically different between Group 1 and Group 2. The presence of high plaque index had significant effect on bone loss. Conclusions After a mean exposure time of 5.2 years postdefinitive prosthesis insertion (range: 1-12 years), implant survival rate of 98.7% was achieved. The six implant failures in three patients occurred after 5 years and affected the prosthesis survival. Soft tissue recession was the most frequent minor biologic complication, whereas peri-implantitis was the most frequent major biologic complication. A 10-year implant-based mucosal recession rate of 77% (95% CI: 68.2-87.9) and a 10-year implant-based peri-implantitis rate of 20% (95% CI: 16.9-24.9) were found.

Objectives The aim of this study was to present the clinical outcomes of patients with an edentulous maxilla treated with a removable prosthesis without palatal coverage retained by Locator abutments on three titanium implants. Material and methods All the patients in a private dental clinic consecutively treated up to 6 years earlier were invited for a follow-up examination (n = 23). Two implants were placed bilaterally and one implant anteriorly in a tripod pattern. All patients underwent a clinical and radiological examination and completed questionnaires related to their experiences and satisfaction with the reconstructions. The prosthesis and implants were examined for adverse biological or technical aspects. Patient satisfaction and quality of life outcomes were collected using a self-reported Denture Satisfaction Scale and OHIP-20. Statistical analyses were limited to descriptive statistics. Results Twenty-one of 23 invited participants consented to participate. We report in this study the outcomes of the study participants who had received their implants more than 2 years ago (n = 12). None of their 36 implants gave any indications of mobility or tenderness upon percussion. Suppuration was observed on one implant. Probing around the implants caused no (53%) or minor bleeding (47%). The incidence of adverse biological and technical events was near non-existent. The rates of replacement of male attachments varied, as did any changes of male attachment retention force. All participants described the task of insertion and removal of the prosthesis as unproblematic. The marginal bone loss ranged between 0 and 5.3 mm. The OHIP-20 and the Denture Satisfaction Questionnaire scores were high. Conclusions The results in this clinical study are positive and promising. Admittedly, the study design is purely retrospective and observational with a small participant cohort, so the technical solution of placing three implants in the edentulous maxilla to retain a removable prosthesis should be appraised further in more controlled studies.

Objective To evaluate the 3-year clinical and radiographic data of fixed implant-supported dental prosthesis delivered to patients having taken alendronate 35–70 mg weekly for at least 3 years before implant placement. Materials and Methods Forty consecutive patients treated with oral bisphosphonates and requiring an implant-supported restoration were recruited in two private centers between January 2008 and December 2011. Implants were inserted through minimally invasive approach under antibacterial and antibiotic treatment, 6 months after alendronate administration stopping. After 4 months of submerged healing, implants underwent prosthetic loading. Hygiene maintenance and clinical assessments were scheduled every 4 months for 3 years. Outcome measures were the following: implant and prosthetic success, survival rates, any observed clinical complications, marginal bone remodeling, probing pocket depth and bleeding-on-probing. Results At the end of the study, eight patients dropped out. The final sample size resulted in 32 consecutive partially or fully edentulous patients (32 females; mean age 64.6 years) with 98 submerged implants. In only one patient, maxillary implant failed during healing period. No prosthesis failed during the entire follow-up, and no major complications were recorded. Implant and prostheses success resulted in an overall survival rate of 98, 98% and 100%, respectively. Three-year mean marginal bone loss was 1.35 ± 0.21 (CI 95% 1.24–1.38). Successful soft tissue parameters were found around all implants. Conclusions Oral bisphosphonate therapy did not appear to significantly affect implant survival and success in case of accurate treatment time selection, minimally invasive surgical approach and constant follow-up. Further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm these results.

PURPOSE This study aimed to evaluate patient satisfaction and prosthetic aspects during a 5-year prospective clinical study of mini dental implants (MDIs) retaining mandibular overdentures. MATERIALS AND METHODS This observational prospective clinical study was conducted on a group of completely edentulous patients (n = 28) with retention problems of conventional mandibular dentures. All patients received new maxillary and mandibular conventional dentures. A total of 112 MDIs (four per patient) were inserted using the flapless surgical approach and immediately loaded by the new mandibular dentures (overdentures). Patients indicated satisfaction with their prosthesis using a questionnaire and a visual analogue scale (VAS). Patient satisfaction and prosthetic complications were recorded 6 months (T6 m ), 1 (T1), 3 (T3), and 5 (T5) years after overdenture insertion. RESULTS The patient satisfaction with eating (hard/soft) food (P

Objective Long‐term success of dental implants depends on healthy peri‐implant soft tissues and adequate bone levels. This prospective study aims to assess bone level changes around implants with internal conical connection and platform‐switching abutments in the posterior mandible. Material and methods Adult patients missing at least two teeth in the posterior mandible and with a natural tooth mesial to the implant site received two or three adjacent internal conical connection implants. After a minimum transmucosal healing period of 8 weeks, single crown restorations were cemented over platform‐switching abutments. Changes in marginal bone levels were measured in standardized periapical radiographs from surgery and loading (baseline) to 12 months post‐loading. Results Twenty‐four patients received 52 implants. Bone remodeling took place between surgery and loading (−0.53 ± 0.40 mm). From loading to 12 months, there was a mean bone gain of 0.12 ± 0.42 mm which occurred mainly in the first 6 months after prosthesis delivery (0.11 ± 0.36 mm) and stabilized afterward. A total of 71.7% of all implants presented bone preservation or gain. No implant was lost at 1 year and the success rate was 100%. Patient inquiry revealed high satisfaction. Conclusion Internal conical connection implants with platform‐switching abutments presented high success rate and enhancement or preservation of marginal bone levels after 1 year of loading.

Purpose The aim of this study was to verify the reliability of a system for the fixed retention of complete maxillary prostheses supported by four implants with a follow-up of 2 years. Material and methods Patients were treated between September 2009 and December 2010 with four Straumann Bone Level SLActive implants supporting a complete prosthesis (CPs). The two distal implants were positioned mesially to the maxillary sinus and with a mesio-distal inclination ≤ 30° in order to reduce the distal prosthesis cantilever. An immediate loading surgical protocol was used. The CPs were planned to be fixed to multibase abutments to test their retention for a fixed rehabilitation. Clinical and radiographic parameters as probing pocket depth (PPD), bleeding score (mBI), plaque index (PI), and marginal bone loss (MBL) were assessed at a 1- and 2-year follow-up visits. Moreover, any biological and prosthodontic maintenance events were recorded. Clinical and radiographic parameters changes were analyzed. Results Twenty-one patients treated with a total of 84 implants completed the 2-year examination period. Four patients were lost to follow up. No technical complication was recorded. Also, no implant, reconstruction, or abutment failures were observed. Therefore, an implant and prosthetic survival rate of 100% were achieved after 2 years. The mean periodontal parameter scores after 2 years of function were 2.6 mm for PPD (SD 0.8 mm), 0.3 for mBI (SD 0.5 mm), and 1.2 for PI (SD 0.4 mm) indexes, respectively. In addition, the mean MBL score measured at the 2-year follow-up visit was −0.34 mm (SD of −0.45 mm). Furthermore, no peri-implant soft tissue inflammation or peri-implant infection was observed. Conclusions It has been shown that immediate loading of four implants positioned anteriorly to the maxillary sinus could be a reliable treatment procedure to support fixed complete restorations.

Objective To evaluate the volumetric changes occurring from prosthesis insertion to the 1-year follow-up (FU) using one- and two-piece dental implants. Methods Sixty patients were randomly assigned to receive one-piece or two-piece implants. Casts were obtained at baseline (insertion of final reconstruction) and at 1 year of loading. Finally, 33 pairs of casts (BRA = 18, STM = 15) were deemed appropriate for volumetric analysis of the peri-implant tissues. If the patients had more than one implant, one was randomly selected for analysis. Casts were scanned to obtain stereolithography (STL) files. Baseline and 1-year FU digital models were superimposed with an image analysis program. Linear and volumetric measurements were performed including (i) crown height changes (CHCs), (ii) volumetric changes, and (iii) changes in tissue thickness at three levels below the mucosal margin on the buccal side of the implants (at 1,3, and 5 mm). The Mann–Whitney U-test and the paired t-test were used to analyze the data between the two groups using the patient as the unit of analysis. Results No significant baseline differences were observed between the one- and two-piece groups for the linear measurements. The mean CHCs in the two-piece group amounted to 0.02 mm (SD ± 0.32), whereas the one-piece group exhibited a change of −0.17 mm (±0.57). The mean volume changes (VCs) were −0.12 mm (±0.27) (two-piece group) and −0.03 mm (±0.29) (one-piece group). With regard to the changes in tissue thickness, the two-piece group presented a change of −0.15 mm (±0.20) at 1 mm, −0.06 mm (±0.20) at 3 mm, and −0.2 mm (±0.51) at 5 mm. The respective values for the one-piece group were −0.03 mm (±0.35), 0.01 mm (±0.28), and −0.01 mm (±0.51) at the three levels. None of the differences in linear measurements between baseline and the 1-year FU reached significance. Positive correlations were seen for tissue thickness changes at 1 and 3 mm for both groups (P

Objective To analyze marginal bone loss (MBL) and clinical parameters around narrow-diameter implants (NDIs – 3.3 mm) made of titanium/zirconium alloy (TiZr) in comparison with commercially pure titanium (cpTi) installed in the molar region of the mandible after 1 year in function. Materials and methods Ten patients participated in the study. A TiZr and a cpTi NDI were randomly installed in contralateral molar sites of the mandible of each patient in a split-mouth design. Eight weeks after healing, all metal–ceramic single crowns were adapted to the implants and patients were enrolled in a plaque control program. MBL at the mesial and distal aspects of the implants were evaluated by comparing periapical radiographs taken immediately after prosthesis installation (T1) and 1 year after loading (T2). Clinical probing depth, bleeding on probing, suppuration, visible plaque and implant mobility were evaluated to determine implant success and survival rates. Results Mean MBL at the interproximal aspects of TiZr implant sites was 0.32 ± 0.27 mm, while at cpTi implant sites mean MBL was 0.35 ± 0.24 mm (P = 0.60). Both TiZr and cpTi NDIs presented 100% implant survival and success rates, with no significant differences in the clinical parameters studied (P > 0.05). Conclusion TiZr and cpTi NDIs presented similar outcomes after 1 year in function in the molar region of the mandible. The results suggest that TiZr and cpTi NDIs may be equally used to support single crowns in the posterior area of the mouth. However, further studies with longer follow-up periods are necessary to confirm these findings.

Objective The objective of this investigation was to determine the clinical and radiographic outcome of a one-piece alumina-toughened zirconia (ATZ) oral implant for single tooth replacement after 1 year. Materials and Methods A total of 27 patients received one ATZ implant each in a one-stage implant surgery with immediate temporization. Standardized radiographs were taken at implant insertion and after 1 year to monitor peri-implant bone loss. Several soft tissue parameters were evaluated at prosthesis insertion and at the 1-year follow-up. Results Three patients did not receive a prosthetic reconstruction due to implant loss during the healing period. As a result, 24 patients were seen at the 1-year follow-up, giving a cumulative survival rate of 88.9%. The average marginal bone loss after 1 year was 0.77 mm. Only two implants (8.3%) lost at least 2 mm bone, whereas none of the implants lost more than 3 mm. Probing depth and clinical attachment level increased over 1 year at the implant sites, whereas gingival recession remained stable. Mombelli's bleeding and plaque indices showed no statistically significant change within the first year. Conclusion Owing to a total of 27 inserted implants, three failures within the first 4 months after implant placement carry weight. Therefore, the cumulative survival rate of the presented ceramic implant was slightly below reported survival rates of titanium implants when immediately restored. The recorded radiographic bone loss and peri-implant soft tissue parameters showed promising short-term results. The presented ATZ implant seems to be a candidate for clinical usage.

Objective To compare the survival rate and alveolar bone levels at implants installed in healed sites and functionally loaded within 1 h from installation or after 3 months. Material and methods A total of 30 patients (17 male and 13 female) were recruited and 71 implants with a SLA® surface, 4.1 mm in diameter and 8–12 mm long, were installed in a fully healed alveolar ridge, 36 as test and 35 as control implants. The test implants were immediately loaded with a temporary reconstruction in proper occlusion, while the randomly selected control sites received the final reconstruction after 3 months. Radiographic bone levels were determined after implant installation, prosthesis delivery, and at annual intervals thereafter. Results One patient of the control and one patient of the test were excluded from evaluation. No further losses of implants or patients were seen up to the 3-year follow-up. Hence, data from 28 patients were accounted for. A total of 37 and 36 metal–ceramic crowns were provided at the test and control sites, respectively. No biological and technical complications were observed during the 3-year follow-up. Bone levels at the time of implant installation were at 1.6 ± 0.8 and 1.7 ± 0.9 mm from the implant shoulder at the test and control sites, respectively. At prosthesis delivery, the bone levels were located at 2.4 ± 0.7 mm at the control sites 3 months after implant placement. After 1 year of function, similar bone levels were observed at both sites, displaying 2.4 ± 1.0 and 2.5 ± 0.8 mm at the test and control sites, respectively. No differences were found in the subsequent observation periods. Conclusion Survival rates and radiographic bone levels after 1, 2, and 3 years of observation did not differ between conventionally installed implants loaded immediately or delayed (after 3 months). Moreover, insertion torque values did not affect osseointegration.

OBJECTIVE To evaluate the influence exerted by different dental specialty backgrounds as well as the validity and reproducibility of the Pink Esthetic Score/White Esthetic Score (PES/WES) and the modified Implant Crown Aesthetic Index (mod-ICAI) on the assessment of esthetic aspects of maxillary implants supported single-tooth prosthesis. MATERIAL AND METHODS A total of fourteen examiners (Two orthodontists, two prosthodontists, two oral surgeons, two periodontists, two dental technicians, two dental assistants, and two postgraduate students in Implant Dentistry evaluated 20 photographs of single-implant-supported crowns and five photographs of unrestored teeth of esthetic zone in a two part study. The examiners assessed the photographs with each index (Pink Esthetic Score/White Esthetic Score and modified Implant Crown Aesthetic Index), twice with a week's interval. Orders of photographs were rearranged in the second assessment. RESULTS Kruskal-Wallis test results showed significant differences among all the six specialties (P ≤ 0.001). DAs and periodontists had significantly better ratings than other specialties with both indices. Prosthodontists had the lowest mean rank scores regardless of the index. Interobserver agreement was also lowest between the two prosthodontists (4-28%), rest of the groups had low-to-moderate agreement (20-80%) when limited allowance was accepted. With mod-ICAI, more interobserver agreement was noted within the specialty group than with PES/WES. CONCLUSIONS The PES/WES and the modified ICAI can be reliable estimates of esthetic outcomes. The assessor degree of specialization affected the esthetic evaluation with both the PES/WES and the modified ICAI. DAs and periodontists were identified to provide more favorable ratings than other specialties while prosthodontists were most critical in this study. With modified ICAI, more interobserver agreement within specialty resulted. The interexaminer agreement may be increased if more tolerance of 1-2 points is considered.

The aim of this prospective clinical study was to evaluate the masticatory function (MF) and subjective perception of patients with poor denture-bearing tissue in relation to change and the time required to identify an improvement in these parameters after rehabilitation with mandibular overdentures (MO) by two narrow-diameter two-piece implants.Twenty-three edentulous patients were selected for MO installation. The masticatory function (MF) was evaluated with the masticatory performance (MP) and swallowing threshold (ST) tests. In the MP test, each volunteer was instructed to masticate a portion of Optocal (standardized artificial test food) for 40 masticatory cycles. During the swallowing threshold test, the patients were instructed to chew a new portion of Optocal cubes until they felt the desire to swallow. The MF tests were performed while complete denture (CD) wearers (baseline) and 1, 3, 6, and 12 months after MO loading. In addition, the subjective perception was assessed through the questionnaires Dental Impact on Daily Living (DIDL), Geriatric Oral Health Assessment Index (GOHAI), and Oral Health Impact Profile in Edentulous (OHIP- EDENT) at the baseline and 3, 6, and 12 months after MO loading.A significant improvement in masticatory function (p .05) was observed already in the first month of loading. Three months after MO loading, a significant improvement (p .05) was found in the subjective perception of patients. The effect size indicates that the MO had the greatest impact on the domains related to function and comfort of all questionnaires and in relation to psychosocial domain of the GOHAI. The level of patient satisfaction increased significantly after the MO loading and reached90% satisfied patients at 12 months.The MO improved both the MF of the patient and their oral health-related quality of life and satisfaction regarding the prosthesis in a short time period.

Objectives The objective of this 3-year split-mouth randomized controlled clinical study was to compare narrow-diameter implants (NDIs) to regular-diameter implants (RDIs) in the posterior region of the jaws (premolars and molars) in regards to (i) the marginal bone level (MBL) and (ii) implant and prosthesis survival and success rates. Material and Methods A total of 22 patients were included in the study. Each patient received at least one implant of each diameter (O3.3 and O4.1 mm), placed either in the maxilla or mandible to support single crowns. A total 44 implants (22 NDIs and 22 RDIs) were placed and included in the study. Twenty-one implants were placed in the premolar, whereas 23 were placed in molar areas. Radiographic evaluations to access the MBL were performed immediately after implant placement, 1 and 3 years after implant loading. Peri-implant clinical variables including probing pocket depth (PPD) and bleeding on probing (BoP) were obtained after crown delivery, 1 and 3 years after loading. Furthermore, the survival and success rates of the implants and prosthesis were also evaluated. Results Twenty patients were able to complete the study. There was no statistically significant difference regarding MBL between groups at implant placement (p = .084), 1-year (p = .794) and 3-year (p = .598) time intervals. The mean peri-implant bone loss at 3-year follow-up was −0.58 ± 0.39 mm (95% CI: −0.751 to −0.409) and −0.53 ± 0.46 mm (95% CI: −0.731 to −0.329) for NDIs and RDIs, respectively. BoP was present at 15% and 10% of NDIs and RDIs, respectively, at 3-year follow-up. PPD >5 mm was observed in 5% and 0% of the implants of NDIs and RDIs, respectively, at 3-year follow-up. At the 3-year examination, the implant success rates were in the NDIs and RDIs sites, respectively, 95% and 100%. The corresponding values for prosthesis success rates were 90% for NDIs and 95% for RDIs. Conclusion The present study demonstrated that NDIs placed to support single crowns in the posterior region did not differ to RDIs in regards to MBL, implant survival, and success rates.

Purpose The aim of this retrospective case–control study was to evaluate the intermediate long-term clinical performance and success rate of dental implants inserted into sites of previous early implant failure. Material and methods A retrospective evaluation was conducted on 6456 patients with 10,234 implants from January 2004 to December 2011. The patients with early implant failure retreated in previous failed sites were enrolled in the study. The collected data included patient′s characteristics, implants characteristics (failed and replaced), and if was the case, any additional surgery performed prior or at the same of implant placement to obtain proper hard tissues dimensions. Moreover, peri-implant clinical parameters, marginal bone loss (MBL), and the implant quality scale (IQS) of the replacement implants were recorded after delivering of the final prosthesis and annually thereafter. Results Ninety-six patients (100 implants) showed initial early failure (failure rate = 0.98%). Sixty-six patients (male: 38; female: 28; mean age: 42.3 ± 18.2 years old) with early implant failure received a total of 67 replacement dental implants. Three patients with three implants dropped out of the study during the mean follow-up of 69.4 ± 27.0 months. The implant length and diameter were varied for seven sites. The number of sites that required additional surgeries increased from 18 to 24 for first and replacement implant insertion, respectively. One of the 67 replacement implants failed before prosthesis delivery, and one implant failure occurred 20 months after prosthesis delivery, which represented a cumulative survival rate of 94.6%. At last follow-up evaluation, the overall mean MBL was 1.7 ± 1.3 mm. Two of 64 implants failed according to IQS criteria, three implants showed satisfactory survival, and one implant showed compromised survival. No pain or tenderness was observed in the rest 58 implants evaluated, showing a success rate (optimum health) of 90.6%. Conclusion Within the limits of the present study, early implant failure was not an obstacle for implant replacement at the same site after an adequate soft and hard tissues healing period.

Objectives To describe a minimally invasive technique for lateral maxillary sinus elevation and to identify the relationship between the involved factors. Materials and methods This is a retrospective study on patients treated with an original minimally invasive technique for lateral maxillary sinus elevation in a private dental clinic from 2008 to 2013. Failures, complications, and radiographic measurements were registered 9 months after surgery at the provisional prosthesis delivery. The relationship between demographic and clinical factors was investigated using Bayesian network analyses. Results One hundred and twenty-four patients (147 maxillary sinuses) were treated, and 242 implants were placed. Seven patients dropped out. A total of two implants in two patients failed. Perforation of the sinus membrane occurred in seven patients (6%). Five different complications in five patients were observed. Mean peri-implant marginal bone level 9 months after surgery was 1.10 ± 0.74 mm. Mean vertical bone gain was 7.44 ± 1.95 mm. Perforation was more frequently observed in patients that did not undergo the sedation procedure. Complications (excluding perforation and including implant failure) were more frequent in cases where only bone substitutes were used. Conclusions This technique can be considered noninvasive, with a low early failure and early complication rate.

Although peri-implant bone loss is one of the parameters included in the criteria for determining implant success, its prevention is of vital importance. The goal of this article is to assess the factors that affect peri-implant bone loss.An observational, longitudinal, retrospective study was conducted in 148 partially edentulous patients rehabilitated with implants and with a follow-up period of 5 years or more. A total of 585 implants were included in the study. Radiographic peri-implant bone loss was compared with radiographic periodontal bone loss, and other characteristics such as prosthesis design, hygiene, and implant size were studied as potential peri-implant bone loss modification factors.In the univariate analysis, a statistically significant relationship between peri-implant bone loss and gender (P 0.05), implant system (P 0.01), reason for extraction (P 0.05), splinting (P 0.0001), and distance between the implant platform and the horizontal component of the prosthesis (P 0.0001) were observed. In multivariate analysis, the relationship between this peri-implant loss and gender (P 0.05), implant system (P 0.05), splinting (P 0.001), and the aforementioned distance (P 0.01) remains.The distance implant platform-horizontal component of the prosthesis has the greatest effect on peri-implant bone loss This distance must be3.3 mm and6 mm, above this range, it no longer influences in peri-implant bone loss and favors the appearance of embrasures and the buildup of bacterial plaque.

Objectives Rehabilitation with implant-supported fixed prostheses is a predictable modality to restore lost function and esthetics; however, fixed restorations are subject to biological and prosthetic complications, which may represent a problem in the long-term. The aim of this study was to evaluate the long-term survival and complication rates of fixed restorations supported by Morse-taper connection implants. Materials and Methods Between January 1992 and December 2002, 49 patients (age range 22–70 years), were included in this study. The restorations involved 58 fixed reconstructions (15 single crowns [SCS], 29 partial prostheses, 14 full-arches), supported by 178 Morse-taper connection implants with a follow-up ranging from 10 to 20 years. Outcomes such as implant survival, marginal bone loss, frequency of biological and prosthetic complications as well as “complication-free” survival of restorations were investigated. Results The 20-year overall cumulative implant survival was 97.2%. A few biological (3.4%) and prosthetic (10.3%) complications were reported. The “complication-free” survival rate of restorations was 85.5%. No statistically significant differences were observed among patients' gender, age, smoking or parafunctional habits, prosthesis site and type. Conclusions Satisfactory “complication-free” survival rates can be achieved after 20 years for fixed restorations supported by Morse-taper connection implants, with minimal marginal bone loss and complications.

Objective To evaluate the influence of different insertion torques on healing of implants loaded immediately or left unloaded. Material and methods In six Labrador dogs, all mandibular premolars and molars were extracted. After 4 months of healing, flaps were elevated, and two implant sites were prepared at each side of the mandible. The distal sites were prepared conventionally while the mesial sites were underprepared by 0.3 mm. As a consequence, different final insertion torques of about 30 Ncm at the distal and >70 Ncm at the mesial sites were recorded. Healing abutments were applied to the left and transmucosal abutments to the right side. Flaps were sutured, crown preparation of the upper right second and third premolars was performed, and impressions were taken. Within 24 h, crowns were cemented both to implants and teeth in the right side of the mouth. After 4 months, the animals were sacrificed and ground sections obtained for histological evaluation. Results A higher buccal bony crestal resorption and a more apical position of the coronal level of osseointegration were found at the loaded compared with the unloaded sites. MBIC% and percentages of peri-implant mineralized tissue (MB%) were higher at the loaded compared with the unloaded sites. Moreover, a higher MBIC% was found at the lower compared with the higher final insertion torque. Conclusions Immediate loading does not seem to have a negative effect on osseointegration. High torque values for the immediate loading procedures were not necessary. Probably, low torque values, were sufficient to obtain primary stability and hence may provide better osseointegration than high torque value.

This study evaluated the screw joint stability after cyclic loading of implant-supported titanium and zirconia CAD/CAM frameworks for fixed dental prostheses (FDPs) with different retention methods.Twenty four one-piece frameworks supported by six threaded implants placed in the maxilla were fabricated using a CAD/CAM technique (NeoShape). Dry-pressed porcelain crowns were luted to the frameworks to standardize the specimens. The specimens were then divided into four groups (n = 6) according to framework material (titanium or zirconia) and retention method for the prosthesis (cement- or screw-retained): G1, Ti-cemented; G2, Ti-screw-retained; G3, Zr-cemented; and G4, Zr-screw-retained. A digital torque ratchet was used to assess the initial preload removal torque. Torque was then reapplied and the specimens were submitted to a 200 N cyclic load, at a frequency of 2 Hz, underwater in controlled temperature of 37°, and for 1 × 106 cycles. An opposing lower dental arch was fabricated using bis-acrylic resin to simulate occlusal contacts in centric. After cyclic loading, postload removal torque was measured. Preload and postload torque loss was expressed as a percentage of the initial load. Data were submitted to a linear mixed-effects model for statistical significance (α = 0.05) to evaluate the effect of cyclic loading in the screw torque loss used with frameworks of different materials and retention methods.Significant screw torque loss (%) was found for the tested groups (before/after cyclic loading, respectively): G1 (39.77/61.83), G2 (37.57/50.96), G3 (34.87/54.10), and G4 (47.56/73.50) (P0.05).The screw removal torque was significantly reduced for all groups in this study after cyclic loading the specimens. Screw-retained zirconia specimens presented the highest torque loss before and after the cyclic loadings compared with the other specimens that were tested.

To investigate the impact of a cross-linked- (VN) collagen membrane on the long-term stability of peri-implant health over 6 years.Vestibular dehiscence-type defects at titanium implants (19 patients, 19 implants) were augmented using a natural bone mineral and randomly allocated to either VN or a native collagen membrane (CM) and left to heal in a submerged position for 4 months. Clinical parameters (i.e. Bleeding on Probing-BOP, probing pocket depth-PD, mucosal recession-MR) were recorded at 4 and 6 years after prosthesis installation.At 4 and 6 years, both VN and CM revealed comparable mean BOP, PD and MR values at both vestibular and oral aspects. Changes in these parameters from 4 to 6 years were minimal (vestibular aspect-VN: -3.3 ± 48.2%, -0.1 ± 0.5 mm, -0.1 ± 0.3 mm; CM: -1.8 ± 33.7%, 0.0 ± 0.4 mm, -0.1 ± 0.7 mm) and not significantly different between groups. At 6 years, the incidence of mucositis and peri-implantitis was comparable in both groups (VN: 60.0% and 20.0%; CM: 33.3% and 33.3%).In conclusion, the present follow-up observation failed to identify any beneficial impact of VN over CM on peri-implant health at 4 and 6 years.

Objective The aim of this study was to verify the reliability of a conometric system for a fixed retention of complete prostheses (CPs) on four implants followed for 2 years. Material and methods Twenty-five patients received four implants and only one CPs for a total of 100 implants followed. Each prosthesis was supported by four implants. An immediate loading surgical protocol was used. The CPs were provided to be fixed to conometric abutments without prostheses removal by the patients, to test this retention for a fixed instead of a removable rehabilitation. Clinical and radiographical parameters were assessed at the yearly follow-up visit. A follow-up of 2 years was observed for each patient. Moreover, biological and technical complications were recorded. Changes overtime of clinical and radiographic parameters were analyzed as well as the satisfaction degree for each patient. Results No patient was classified as “dropout.” The following results were observed after 2 years of follow-up: all the implants supporting the 25 CPs completed the follow-up examination. No implant, reconstruction, and abutment failure were recorded; therefore, the prosthetic survival was 100% for all the abutments and restorations. No significant differences in biological indexes were observed when compared with the baseline. No significant change of the mean marginal bone level (MBL) was found between the baseline and the last follow-up. No loss of retention was recorded for the CPs. No technical complications referred to abutments and frameworks were observed: a prosthetic survival rate of 100% can be recorded. Mucositis was recorded for two implants and successfully treated with interceptive supportive therapy. No significant differences (P

Purpose The aim of this study was to assess the use of single implant–supported, magnet-retained mandibular overdentures to improve the oral health–related quality of life (OHRQoL) and masticatory performance of patients wearing conventional complete dentures. The study also aimed at comparing the OHRQoL, masticatory performance, and crestal bone loss with two different types of overdenture prosthesis. Materials and methods Ten completely edentulous patients with atrophic mandibular residual alveolar ridges and having difficulty coping with technically adequate mandibular dentures were selected for implant-supported overdentures (ISOD). To assess the success of the implant fixture clinically, a crossover study design was followed, and the patients were divided into two groups. Group A received ISOD with conventional complete dental arch, and group B received ISOD with a shortened dental arch for the first 3 months and vice versa for the next 3 months. The OHRQoL was measured with the OHIP-49 questionnaire, and masticatory performance was assessed with the sieve method using peanuts as test food. Peri-apical radiographs were taken to evaluate the crestal bone loss. Results A significant improvement was seen both subjectively and objectively when conventional complete dentures were modified to implant-supported prosthesis. When comparing the implant overdenture prosthesis, patients were more satisfied with conventional arch than with the shortened dental arch. In the first 3 months following implant placement, less bone loss was seen with the shortened dental arch overdenture (P