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© 2021 American Academy of PeriodontologyBackground: Peri-implantitis (PI) is a growing concern in the dental community worldwide. The study aimed to compare U.S. versus European periodontists’ considerations of risk factors, diagnostic criteria, and management of PI. Methods: A total of 393 periodontists from the United States and 100 periodontists from Europe (Germany, Greece, Netherlands) responded to anonymous surveys electronically or by mail. Results: Compared to U.S. periodontists, European respondents were younger, more likely to be female and placed fewer implants per month (9.12 vs 13.90; P = 0.003). Poor oral hygiene, history of periodontitis, and smoking were considered as very important risk factors by both groups (rated > 4 on 5-point scale). European periodontists rated poor oral hygiene (4.64 vs 4.45; P = 0.005) and history of periodontitis (4.36 vs 4.10; P = 0.006) as more important and implant surface (2.91 vs 3.18; P = 0.023), occlusion (2.80 vs 3.75; P < 0.001) and presence of keratinized tissue (3.27 vs 3.77; P < 0.001) as less important than did U.S. periodontists. Both groups rated clinical probing, radiographic bone loss, and presence of bleeding and suppuration as rather important diagnostic criteria. They rated implant exposure/mucosal recession as relatively less important with U.S. periodontists giving higher importance ratings than European periodontists (3.99 vs 3.54; P = 0.001). Both groups nearly always used patient education, plaque control and mechanical debridement when treating PI. U.S. periodontists were more likely to use antibiotics (3.88 vs 3.07; P < 0.001), lasers (2.11 vs 1.68; P = 0.005), allograft (3.39 vs 2.14; P < 0.001) and regenerative approaches (3.57 vs 2.56; P < 0.001), but less likely to use resective surgery (3.09 vs 3.53; P < 0.001) than European periodontists. Conclusions: U.S. and European periodontists’ considerations concerning risk factors, diagnosis and management of PI were evidence-based. Identified differences between the two groups can inform future educational efforts.

Mechanical fixation of the implant to host bone is an important contributor to orthopaedic implant survivorship. The relative importance of bone-implant contact, trabecular bone architecture, and cortical bone geometry to implant fixation strength has never been directly tested, especially in the settings of differential implant surface properties. Thus, using a rat model where titanium rods were placed into the intramedullary canal of the distal femur, we determined the relative contribution of bone-implant contact and peri-implant bone architecture to the fixation strength in implants with different surface roughness: highly polished and smooth (As-received) and dual acid etched (DAE) implants. Using a training set that maximized variance in implant fixation strength, we initially examined correlation between implant fixation strength and outcome parameters from microcomputed tomography and found that osseointegration volume per total volume (OV/TV), trabecular bone volume/total volume (BV/TV), and cortical thickness (Ct.Th) were the single best compartment-specific predictors of fixation strength. We defined separate regression models to predict implant fixation strength for As-received and DAE implants. When the training set models were applied to independent validation sets, we found strong correlations between predicted and experimentally measured implant fixation strength, with r(2) = 0.843 in As-received and r(2) = 0.825 in DAE implants. Interestingly, for As-received implants, OV/TV explained more of the total variance in implant fixation strength than the other variables, whereas in DAE implants, Ct.Th had the most explanatory power, suggesting that surface topography of implants affects which bone compartment is most important in providing implant fixation strength.

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.

Aim To evaluate an additional mechanical approach, a titanium brush, in the implant surface decontamination performed during the regenerative surgical therapy of peri-implantitis. Material and methods A randomized double-blinded clinical trial, with a 1-year follow-up, was carried out. After a hygienic phase, peri-implantitis-affected implants were randomly assigned to a control or to a test group. In the control group, implant surface was decontaminated both mechanically and chemically with 3% H2 O2 and plastic ultrasonic scalers, respectively, while in the test group, a titanium brush was also applied. Intrabony defects in both groups were filled with an alloplastic material (β-tricalcium phosphate and hydroxyapatite) and covered with a collagen membrane. The primary outcome was the reduction in probing pocket depth (PPD) at the deepest site. Results Thirty patients were included, 15 in each group. At 12 months, reduction in PPD was 4.87 (standard deviation [SD] 1.55) mm and 2.85 (SD: 1.91) mm, respectively (p = 0.009). The correspondent figures for residual PPD were 3.6 (SD: 0.91) and 4.92 (SD: 1.26) mm, respectively (p = 0.007). Conclusions The additional use of a titanium brush during regenerative treatment of peri-implantitis resulted in statistically significant benefits in terms of PPD reduction after 12 months.

Background The understanding of mechanisms of osseointegration as well as applied knowledge about oral implant surfaces are of paramount importance for successful clinical results. Purpose The aim of the present article is to present an overview of osseointegration mechanisms and an introduction to surface innovations with relevance for osseointegration that will be published in the same supplement of Clinical Implant Dentistry and Related Research. Materials and methods The present article is a narrative review of some osseointegration and implant surface-related details. Results and conclusions Osseointegration has a changed definition since it is realized today that oral implants are but foreign bodies and that this fact explains osseointegration as a protection mechanism of the tissues. Given adequate stability, bone tissue is formed around titanium implants to shield them from the tissues. Oral implant surfaces may be characterized by microroughness and nanoroughness, by surface chemical composition and by physical and mechanical parameters. An isotropic, moderately rough implant surface such as seen on the TiUnite device has displayed improved clinical results compared to previously used minimally rough or rough surfaces. However, there is a lack of clinical evidence supporting any particular type of nanoroughness pattern that, at best, is documented with results from animal studies. It is possible, but as yet unproven, that clinical results may be supported by a certain chemical composition of the implant surface. The same can be said with respect to hydrophilicity of implant surfaces; positive animal data may suggest some promise, but there is a lack of clinical evidence that hydrophilic implants result in improved clinical outcome of more hydrophobic surfaces. With respect to mechanical properties, it seems obvious that those must be encompassing the loading of oral implants, but we need more research on the mechanically ideal implant surface from a clinical aspect.

This study investigated the effects of osseodensification drilling on the stability and osseointegration of machine-cut and acid-etched endosteal implants in low-density bone. Twelve sheep received six implants inserted into the ilium, bilaterally (n = 36 acid-etched, and n = 36 as-machined). Individual animals received three implants of each surface, placed via different surgical techniques: (1) subtractive regular-drilling (R): 2.0 mm pilot, 3.2 and 3.8 mm twist drills); (2) osseodensification clockwise-drilling (CW): Densah Bur (Versah, Jackson, MI) 2.0 mm pilot, 2.8, and 3.8 mm multifluted tapered burs; and (3) osseodensification counterclockwise-drilling (CCW) Densah Bur 2.0 mm pilot, 2.8 mm, and 3.8 mm multifluted tapered burs. Insertion torque was higher in the CCW and CW-drilling compared to the R-drilling (p < 0.001). Bone-to-implant contact (BIC) was significantly higher for CW (p = 0.024) and CCW-drilling (p = 0.006) compared to the R-drilling technique. For CCW-osseodensification-drilling, no statistical difference between the acid-etched and machine-cut implants at both time points was observed for BIC and BAFO (bone-area-fraction-occupancy). Resorbed bone and bone forming precursors, preosteoblasts, were observed at 3-weeks. At 12-weeks, new bone formation was observed in all groups extending to the trabecular region. In low-density bone, endosteal implants inserted via osseodensification-drilling presented higher stability and no osseointegration impairments compared to subtractive regular-drilling technique, regardless of evaluation time or implant surface. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 615-623, 2019.

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

Objective This report is a 20-year follow-up of a randomized controlled clinical trial evaluating the potential long-term effect of a modified implant surface on the preservation of the peri-implant marginal bone level. Material & methods In each of 51 patients and for each fixed partial denture (FPD), by randomization at least one implant installed had a non-modified turned surface and one a modified and roughened surface (TiOblast® ). Clinical and radiological examinations were performed at various follow-up intervals. Primary outcome variables were peri-implant marginal bone level change from time of loading and proportion of implants with no bone loss at 20 years. Multilevel analysis followed by nonparametric and Pearson's Chi-Square tests were applied for statistical analysis. Results At the 20-year follow-up, 25 patients carrying 64 implants were available for evaluation. Turned and TiOblast implants presented with a mean bone level change from the time of FDP delivery amounting to -0.41 mm (95% CI -0.84/0.02) and -0.83 mm (95% CI -1.38/-0.28) respectively (inter-group comparison p > .05). 47% of the Turned and 34% TiOblast implants (p > .05) showed no bone loss. All but one of these implants were free of bacterial plaque and inflammation as well as presented with probing pocket depths ≤5 mm at both the 5- and 20-year follow-up examinations. Conclusion It is suggested that a moderate increase of implant surface roughness has no beneficial effect on long-term preservation of the peri-implant marginal bone level.

OBJECTIVE To histologically assess the hard and soft tissue changes after insertion of cleaned and activated titanium implants using plasma of argon. MATERIALS AND METHODS Eight dogs were included in this study. The mandibular premolars and first molars were extracted. For each hemi-mandible, four implants, 7 mm long and 3.3 mm of diameter, with a ZirTi surface were used. The surface of two implants was randomly treated with argon plasma (test), while the other two implants were left untreated (control). After 1 month, the same procedure was performed in the contralateral hemi-mandible. The amount of old bone, new bone, overall value of old bone plus new bone, and soft tissue was histologically evaluated. RESULTS After 1 month of healing, high percentages of new bone in close contact with the implant surface were found at both the treated (60.1% ± 15.6%; 95% CI 56.5%-78.0%) and untreated (57.2% ± 13.1%; 95% CI 49.3%-67.5%) implants. Low percentages of old bone were found at this stage of healing, at both the treated (4.4% ± 3.0%; 95% CI 1.2%-5.4%) and untreated (3.4% ± 3.1%; 95% CI 0.6%-4.9%) implants. Not statistically significant differences were found between groups (p > .05). After 2 months of healing, treated implants presented a significantly higher (p = .012) new bone formation (72.5% ± 12.4%; 95% CI 69.6%-86.8%) compared to untreated sites (64.7% ± 17.3%; 95% CI 59.4%-83.3%). Controversially, no difference (p = .270) in terms of old bone was present between treated (3.1% ± 1.7%, 95% CI 1.8%-4.2%) and untreated implants (3.8% ± 1.9%, 95% CI 3.2%-5.8%). Significant differences (p = .018) in terms of total mineralized bone were found between treated (75.6% ± 13.0%, 95% CI 73.3%-91.3%) and untreated implants (68.4% ± 16.8%; 95% CI 64.2%-87.6%). CONCLUSIONS Implants treated using plasma of argon was demonstrated to reach a higher bone-to-implant contact when compared to untreated implants.

Peri-implantitis represents a disruption of the biocompatible interface between the titanium dioxide layer of the implant surface and the peri-implant tissues. Increasing preclinical data suggest that peri-implantitis microbiota not only triggers an inflammatory immune response but also causes electrochemical alterations of the titanium surfaces, i.e., corrosion, that aggravate this inflammatory response. Thus, it was hypothesized that there is an association between dissolution of titanium from dental implants, which suggests corrosion, and peri-implantitis in humans. The objective of this study is to compare levels of dissolved titanium in submucosal plaque collected from healthy implants and implants with peri-implantitis.Submucosal plaque from 20 implants with peri-implantitis and 20 healthy implants was collected with sterile curets from 30 participants. Levels of titanium were quantified using inductively coupled plasma mass spectrometry and normalized for mass of bacterial DNA per sample to exclude confounding by varying amounts of plaque per site. Statistical analysis was performed using generalized estimated equations to adjust for clustering of implants per participant.Implants with peri-implantitis harbored significantly higher mean levels of titanium (0.85 ± 2.47) versus healthy implants (0.07 ± 0.19) after adjusting for amount of plaque collected per site (P = 0.033).Greater levels of dissolved titanium were detected in submucosal plaque around implants with peri-implantitis compared with healthy implants, indicating an association between titanium dissolution and peri-implantitis. Factors triggering titanium dissolution, as well as the role of titanium corrosion in the peri-implant inflammatory process, warrant further investigation.

Introduction: Bone loss associated with peri-implantitis can result in exposure of the implant surface. A lack of keratinized mucosa has been associated with increased plaque accumulation, attachment loss, and mucosal recession. This case report describes the benefits of connective tissue (CT) grafting in the treatment of peri-implantitis and gingival recession affecting an implant supporting an overdenture. To the best of the author’s knowledge, there are few clinical case reports depicting this treatment for implants supporting overdentures.Case Presentation: A 75-year-old female was diagnosed with peri-implantitis associated with an implant that supported a mandibular overdenture. The bone loss and gingival recession was on the facial aspect of the implant. The roughened threaded surface of the implant was exposed, and there was an absence of facial keratinized mucosa. Peri-implant therapy included surgical access to debride the area and decontaminate the implant surface using a 3% hydrogen peroxide ri...

Implants with deep thread depth have been developed for the purpose of increasing total implant surface area. However, effects of implant thread depth remain controversial. The aim of this study is to examine effects of thread depth on peri-implant tissues in terms of bone-implant contact (BIC), bone-implant volume (BIV), and hard and soft tissue dimensions using comprehensive analyses, including microcomputed tomography (micro-CT).Five beagle dogs received experimental intramandibular implants 3 months after removal of their premolars and first molars (PThere were no significant differences in resonance frequency test results between the two groups. Although radiographic analysis showed no group differences, micro-CT (P = 0.01) and histomorphometry (P = 0.003) revealed the DT group had significantly lower BIC values than the ST group at 4 weeks. However, by 8 weeks, BIC values of the two groups did not differ significantly. No significant differences in BIV or soft tissue height were observed between the two groups at either time point.DT implants showed no benefits over ST implants when inserted in dog mandibles.

This is the peer reviewed version of the following article: Gehrke SA, Mat e S anchez de Val JE, Fern andez Dom ınguez M, de Aza Moya PN, Go mez Moreno G, Calvo Guirado JL. Effects on the osseointegration of titanium implants incorporating calcium–magnesium: a resonance frequency and histomorphometric analysis in rabbit tibia Clin. Oral Impl. Res. 00, 2016, 1–7., which has been published in final form at 10.1111/clr.12909. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. 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. Odontología

This systematic review and meta-analysis evaluated the influence of biological implant surface coatings on periimplant bone formation in comparison to an uncoated titanium reference surface in experimental large animal models. The analysis was structured according to the PRISMA criteriae. Of the1077 studies, 30 studies met the inclusion criteriae. Nineteen studies examined the bone implant contact (BIC) and were included in the meta-analysis. Overall, the mean increase in BIC for the test surfaces compared to the reference surfaces was 3.7 percentage points (pp) (95% CI -3.9-11.2, p = 0.339). Analyzing the increase in BIC for specific coated surfaces in comparison to uncoated reference surfaces, inorganic surface coatings showed a significant mean increase in BIC of 14.7 pp (95% CI 10.6-18.9, p

AIM: To evaluate surface roughness alterations at the smooth neck of dental implants after the use of eight different prophylactic procedures. MATERIALS AND METHODS: 50 tissue level implants (Institut Straumann AG, Basel, Switzerland) were used for the present investigation. The smooth collar of each implant was divided into two segments, each treated with one of eight cleaning procedures: use of a rubber cup (RCZ) or a brush (BZ) combined with an abrasive paste containing zirconium or a paste derived from perlite (RCP, BP); use of 2 composite resin burs reinforced by zirconium glass fibers (F1, F2); and use of an air-polishing system with glycine powder and two power settings (AP1, AP2). The qualitative alterations were recorded by means of a laser profilometer and the mean roughness (Ra ) and mean roughness profile depth (Rz ) were reported. Twenty untreated surfaces were used as controls. RESULTS: The implant collars treated with RCZ (Ra = 0.33 μm, Rz = 2.43 μm) or BZ (Ra = 0.30 μm, Rz = 3.70 μm) yielded the highest roughness values, followed by the surfaces treated with RCP (Ra = 0.28 μm, Rz = 2.02 μm), with BP (Ra = 0.25 μm, Rz = 2.16 μm) and by the use of F1 (Ra = 0.27 μm, Rz = 2.22 μm) and F2 (Ra = 0.27 μm, Rz = 2.04 μm). The lowest roughness values were observed in the AP1 (Ra = 0.23 μm, Rz = 1.60 μm) and AP2 (Ra = 0.16 μm, Rz = 1.06 μm) group, respectively. Implant collars treated with AP2 yielded statistically significantly lower (P = 0.01) Rz values compared with untreated surfaces. CONCLUSION: All tested procedures did not increase implant surface roughness significantly. Treatment with an air-powder abrasive system at high-pressure setting resulted in a smoothening of the implant collar surface.

Degradation of the implant surface and particle release/formation as an inflammation catalyst mechanism is an emerging concept in dental medicine that may help explain the pathogenesis of peri-implantitis. The aim of the present study was a synchrotron-based characterization of micro- and nanosized implant-related particles in inflamed human tissues around titanium and ceramic dental implants that exhibited signs of peri-implantitis. Size, distribution, and chemical speciation of the exogenous micro- and nanosized particle content were evaluated using synchrotron μ-X-ray fluorescence spectroscopy (XRF), nano-XRF, and μ-X-ray absorption near-edge structure (XANES). Titanium particles, with variable speciation, were detected in all tissue sections associated with titanium implants. Ceramic particles were found in five out of eight tissue samples associated with ceramic implants. Particles ranged in size from micro- to nanoscale. The local density of both titanium and ceramic particles was calculated to be as high as ∼40 million particles/mm

WOS: 000462798900017, PubMed: 30821054, Background The chemical surface structure of the porous titanium grafts has not been found to study in the literature on the similarity of chemical surfaces of different commercial dental implants. Purpose The purpose of this study is to investigate the chemical composition and surface energies of white (WPTG) and black porous titanium granules (PTG) by energy dispersive x-ray spectrometry (EDX) analysis to compare with different commercial dental implant surface. Materials and Methods The surface chemical compositions of six commercially available dental implants with different surface structures, PTG and WPTG were examined by EDX analysis. Surface analyzes were performed on the apical, middle, and coronal parts of each implant and on the top, flank, and valley regions on each side. Surface analyzes of dental implants were evaluated at x200 and x2000 magnifications. The EDX evaluation of PTG grafts were evaluated at x250, x2000, x5000, and x50 000 magnifications. Results PTG grafts showed elements of Na (8.88 +/- 9.98%), Cl (2.44 +/- 1.96%), and Al (0.99 +/- 0.37%) as well as Ti (90.06 +/- 11.34%) molecule at x5000 magnification. In WPTG, Ti (%34.55 +/- 6.41%) and O (%65.44 +/- 6.42%) molecules were detected. Conclusions It has been found that PTG surface was not made of pure titanium, it has different chemical molecules at larger magnifications. Cell culture and experimental studies are needed to establish a relationship between the different commercial implants and the surface structure of the titanium granules., Committee of Science Research Projects from the Dumlupnar University, Kutahya, Turkey [2017-29], This research was support by the research grants of the Committee of Science Research Projects (2017-29) from the Dumlupnar University, Kutahya, Turkey.

OBJECTIVES The aim of the present observational medical device performance study was to test whether implants with an intra-operatively conditioned hydrophilic surface can be safely reconstructed when applying an early loading protocol after 21 days in partially edentulous posterior mandibles. MATERIAL AND METHODS Partially edentulous patients with missing teeth in the posterior mandible were recruited. Immediately after implant placement, the implant position was indexed using a pickup impression technique. ISQ values were measured after 21 days of healing. When ISQ values were ≥70, the implants were directly restored with provisional reconstructions in occlusal contact allowing an early loading protocol. ISQ values were repeated again at 1, 3, and 6 months postloading. Clinical parameters (mPLI, mSBI, PPD, DIM, and CAL) were assessed. Standardized periapical radiographs were obtained after surgery, at implant loading and 3 and 6 months later. Changes over time were analyzed for statistical significance using the nonparametric method by Brunner & Langer (SAS Proc Mixed). RESULTS Fifteen partially edentulous patients with healed sites in the posterior mandible received 20 implants. All implants healed uneventfully. At 21 days, all implants achieved an ISQ value of ≥70 (mean of 3 measurements) and were reconstructed at this time point with provisionals. ISQ values showed a gradual increase from baseline to 3 and 6 months postloading. The assessment of clinical parameters revealed stable tissue integration. The evaluation of the radiographs showed that 3 and 6 months after loading the median mesial and distal marginal bone levels had stabilized at the border between the rough surface and the 1-mm machined implant collar. CONCLUSION Functional occlusal loading of implants with a hydrophilic, moderately rough endosseal surface 3 weeks after placement appears to be a safe and predictable treatment option in healed sites in the posterior mandible without need of bone augmentation procedures.

Background Compared with knowledge on patient and implant component factors, little knowledge is available on surgeons' role in early implant failures. Purpose To report incidence of early implant failures related to total number of operations performed by individual surgeons. Materials and Methods Early implant failures (≤1 year of implant prosthesis function) were reported after a total of 11,074 implant operations at one specialist clinic during 28 years of surgery. Altogether, 8,808 individual patients were treated by 23 different dentists, of whom 21 surgeons were specialists in oral surgery or periodontology. Recorded failures were related to total numbers of performed operations per surgeon, followed by statistical comparisons (χ2) between surgeons with regard to type of treated jaw and implant surface. Results Altogether, 616 operations were recorded with early implant failures (5.6%), most often observed in edentulous upper jaws after placing implants with a turned surface (p

The aim of this study is to evaluate the effects of nanoporous anodic aluminum oxide (alumina) with pore diameters from 15 to 40 nm on osteoblasts (hFOB) and fibroblasts (HFF). After 7 days, a significantly higher proliferation of osteoblasts with a regular cell morphology is visible on the 40 nm samples compared to the 15 nm pore diameter (p = 0.003). Fibroblasts, on the other hand, have a significantly higher proliferation rate on the 15 nm pore diameter samples compared to the 40 nm samples (p = 0.000). The pore diameter of AAO affects fibroblasts and osteoblasts in opposite ways and makes it possible to cope in a perfect way with different requirements of cells on the implant surface.

Atmospheric pressure plasma-jets could be an alternative method to remove bacterial biofilms on orthopaedic implants. Furthermore, plasma-exposure might support the proliferation of osteoblasts after cleaning implants by activating the implant surface. In this comparative in vitro study, the efficacy of five different plasma sources concerning removal of bacterial biofilms and influence on human osteoblast cell attachment was tested. Two plasma sources revealed a significant reduction of bacterial viability (>90%) and enhanced spreading of osteoblastic cells. Promising results and potential for local plasma-jet application dealing with implant-related infections caused by bacterial biofilms was demonstrated.

Background Even though there are many studies available reporting on implant failures, there are few studies that follow implant failures over time in large populations. Purpose The purpose of this article is to present an overview of the annual incidence of reported implant failures for patients and operations over a 28-year period. Materials and Methods A total of 8,528 patients were consecutively provided with 39,077 implants in 10,719 implant operations during a 27-year period (1986–2012) at one specialist clinic. All patients with reported failures of implants during a 28-year routine follow-up period (1986–2013) were included, and data from the patients' files were retrieved and reported. Results Altogether, 857 patients (882 jaws/operations) were identified with one or more failures (10.0% of patients/8.5% of operations). Mean annual incidence of first failure showed obvious variations between years, even between seemingly clinically similar situations. However, incidence of first implant failure was higher for upper than lower jaws (p

Although preclinical and sparse human histology retrieval studies have shown that the interface between implant and bone is constantly remodeling, no human retrieval database has been developed to determine the effect of functional loading time and other clinical/implant design variables on osseointegration. The present study tested the hypothesis that bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) increase over functional loading time around dental implants. Due to prosthetic retreatment reasons, 93 human implant retrievals from the same manufacturer (Bicon LLC, Boston, MA, USA) were obtained over a period of approximately 15 years. The retrieved implants were under functional loading from 120 days to ∼18 years and were histomorphologic/metrically evaluated. BIC/BAFO were assessed as a function of multiple independent variables: implant surface type, diameter, length, jaw (maxilla/mandible), region (anterior/posterior), and time of functional loading. The results showed that both BIC and BAFO increased over time independently of implant design/clinical variables, supporting the postulated hypothesis. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1328–1332, 2015.

Objectives To investigate soft tissue histomorphology and quality around implants with a modified transgingival collar surface comparatively to a machined. Material and methods Twenty-seven Straumann Standard Tissue Level implants belonging to the following groups (nine of each group): Ti modSLA with machined collar (Ti-M), Ti modSLA with machined, acid-etched surface collar (Ti-modMA), and TiZr modSLA with machined, acid-etched surface collar (TiZr-modMA) were placed in the mandible of six minipigs. After 8 weeks of healing, buccal sections were obtained and processed for histological evaluation. Results Histometric soft tissue outcomes were similar for the three types of implants. The percentage of connective tissue attached to implant surface and its length was longer at TiZr-modMA with respect to Ti-M implants. The number of inflammatory cells was slightly higher at the TiZr-modMA with respect to Ti-M implant. The percentage of area occupied by perpendicular collagen fibers was slightly higher for the modified surfaces in comparison with the machined. Conclusions Modified implant collar surfaces at Ti and TiZr implants showed a soft tissue interface similar to machined. A tendency of increasing number of perpendicular collagen fibers and improved connective tissue contact was found at the modified implant surfaces.

The choice of material for implanted prostheses is of great importance concerning bacterial colonization and biofilm formation. Consequently, methods to investigate bacterial behavior are needed in order to develop new infection resistant surfaces. In this study, different methodological setups were used to evaluate the antimicrobial effect of photocatalytic titanium oxide and silver surfaces. Biofilm formation and eradication under static and dynamic culture conditions were studied with the use of the following analytical techniques: viable colony-forming unit (CFU) counting, imprinting, fluorescence, and bioluminescence. The present study demonstrates that different methods are needed in order to evaluate the prophylactic and treatment effects on planktonic and biofilm bacteria and to assess the antimicrobial effect of different surface treatments/coatings. Choosing the right antibacterial testing model for the specific application is also of great importance. Both in situ approaches and indirect methods provide valuable complementary information. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014.

For a basic understanding and potential biomedical applications of surface topographical effects on bacterial responses, this study focuses on not only the bacterial retention but also the bacterial growth, proliferation, and viability that are significant post-retentive behaviors playing critical roles in infections of medical implants. Specifically, periodic micropillar arrays (SiPA ) with nine different feature sizes were fabricated on silicon substrates with photolithography and dry etching methods. The SiPA was cultured with Staphylococcus aureus or Escherichia coli for different periods to investigate the bacterial retention, growth and proliferation behavior on a patterned surface. The experimental results show that a significant reduction of bacterial retention, growth, and proliferation can be achieved when the pillar size is reduced to the submicrometer level. However, micropillars have no obvious influence on the viability of the bacteria within 24 h. On the basis of the bacterial experiment results, it is inferred that the topographical effects may have resulted from bacterial confinement by micropillars, either limiting the attachment area for individual bacterium or trapping a bacterium between pillars. Furthermore, the extended Derjaguin-Landau-Verwey-Overbeek theoretical analysis indicates the effects might have come from the topographic induced surface property changes, mainly hydrophobicity, which is represented by the changes in the interaction free energy of Lifshitz-van der Waals among different periodic micropillar arrays. This study could help to deepen the understanding about the surface topographical effects on bacterial responses and may provide a guidance for the future medical implant surface design to decrease the infection risk by avoiding the surface topography which could attract more bacteria.

Introduction: Osteoconductive characteristics of different implant surface coatings are in the focus of current interest. The aim of the present study was to compare the vertical osteoconductivity at the implant shoulder of supracrestal inserted calcium-phosphate coated implants (SLA-CaP) with conventional sand-blasted/acid-etched (SLA) implants in a rabbit model. Materials and Methods: SLA-CaP and SLA implants were inserted bilaterally in the mandible of four rabbits in a split-mouth design. The implants were placed 2 mm supracrestal. After 3 weeks, at the left and right implant shoulder, the percentage of linear bone fill (PLF) as well as bone-implant contact (BIC-D) were determined. Results: After 3 weeks, newly formed woven bone could be found at the shoulder of the most of both surface-treated implants (75%). PLF was significantly higher in SLA-CaP implants (11.2% vs. 46.5%; n = 8, p = .008). BIC-D was significantly increased in the SLA-CaP implants (13.0% vs. 71.4%; n = 8, p

Nowadays medical implants are high-tech products which are designed according to comprehensive experiences from medicine, material science and surface science. A prolonged duration of joint endoprostheses is achieved by a sophisticated surface design according to the different functionality of the implant surface. Therefore the main aspects are wear reduction and stimulated bone apposition to the load-bearing implant surfaces. Different coating methods suit the functional needs. Medical aspects as well as those of technological developments are discussed. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Background Peri-implant mucositis and peri-implantitis are a raising issue in dental implantology. Peri-implant infections are mainly caused by the formation of biofilm. Different surface textures exhibit various conditions for biofilm formation resulting in several speed of maturation and development. Materials and Methods On three different titanium implant surfaces, machined-surface (M), sandblasted large grit, and acid-etched surface (SLA) and machined-modified acid-etched surface (mod MA) initial biofilms were collected. Plaque formation was investigated by erythrosine staining and energy-dispersive X-ray spectroscopy (EDX). For testing the biocompatibility of these plaque-settled surfaces, autoclaved specimens were settled with human gingival fibroblasts, and cell viability was tested. Results The mean initial plaque surface was detected in the following descending order: M > SLA > mod MA. The differences between these groups were significant. The highest cell viability was detected in the M groups, whereas mod MA and SLA showed comparable results. The results of initial biofilm formation were proved by EDX. Conclusions Within the limitations of this study, conclusion can be made that mod MA surface shows significant slower initial biofilm formation which could be an advantage in initial transgingival healing process and also an easement for oral hygiene of patients because maturation of plaque is retarded, and immature biofilms are easier to remove.

Objectives To evaluate the influence of instrumentation technique on the early osseointegration histomorphometrics and biomechanical fixation of fully laser-etched microgrooves implant surfaces in a sheep model. Material and Methods Six sheep were subjected to bilateral hip surgeries 3 and 6 weeks before euthanasia. A total of 48 implants (∅4.5 mm, 8 mm in length) were distributed among four sites (8 per animal) and placed in bone sites drilled to 4.6 mm (reamer), 4.1 mm (loose), 3.7 mm (medium) and 3.2 mm (tight) in diameter. After healing, the animals were euthanized and half of the implants were biomechanically tested, while the remainder was subjected to non-decalcified histologic processing. The histomorphometric parameters assessed were bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Statistical analysis was performed using a mixed-model analysis of variance with significance level set at P

Background: A delayed approach is recommended for reconstruction of the jaws with autogenous bone grafts and dental implants. Experimental studies have shown stronger bone tissue responses to surfa ...

Objectives This study evaluated the reosseointegration of implants that had been reinserted following the mechanical disintegration of immature osseointegration in dogs. Materials and methods Rotationally mobile implants were installed into an oversized drill space in five canine mandibles. After a healing period of 4 weeks, the immature osseointegration of the implant was intentionally disintegrated by the application of a mechanical countertorque and then reinserted at the same site (experimental group); in the control group, the mobile implant remained submerged without any surgical intervention. The animals were euthanized 4 weeks after the disruption of osseointegration. Changes in the implant stability quotient (ISQ) and Periotest value (PTV) were analyzed, and the bone-implant contact (%) was measured histometrically. Results All experimental and control sites showed successful mechanical stability at 8-week healing period. The mean ISQ was significantly higher in the experimental group than in the control group at 8 weeks (P

Objective To study the early sequential stages of osseointegration at implants installed in alveolar bony. Materials and methods In 12 Labrador dogs, all mandibular premolars and first molars were extracted bilaterally. After 3 months of healing, full-thickness flaps were elevated in the edentulous region of the right side of the mandible. Implants were installed, and the flaps were sutured to allow a fully submerged healing. The timing of the installations in the left side of the mandible and of sacrifices were performed with a schedule that various observation periods to sacrifice from 5, 10, 20, and 30 days were available so that n = 6 was obtained per each healing period. Ground sections were prepared and analyzed. Results Newly formed bone in contact with the implant surface was found after 10 days of healing and the percentage increased up to 50% after 1 month of healing. A higher percentage was found in the trabecular compared with the cortical bony compartment. Old bone decreased by about 50% during healing, being still present after 1 month (16%). The proportions of bone debris and bone particles were at 27% after 5 days and decreased during healing to 6% after 1 month. Conclusion Osseointegration (new bone-to-implant contact) developed at various rates for cortical and trabecular compartments, respectively. In the trabecular region, mesenchymal cells were identified, subsequently developing into new bone in contact with the implant surface. In the cortical compartment, however, resorptive processes were observed throughout all periods of healing. The proportion of newly formed bone percentage was lower compared with that of the trabecular area. Old bone was still present after 1 month of healing in both compartments. Bone debris and small bone particles appeared to be involved in initial bone formation.

Objectives To study the incidence of peri-implantitis over 13 years between two types of dental implants. Materials and methods Peri-implantitis incidence was defined as bone loss ≥ 1.0 mm after 1 year, and with BOP or suppuration. Results Nineteen subjects with TioBlast AstraTech™ (AT) and 22 subjects with machine-etched Branemark Nobel Biocare® (NB) implants were studied. The incidences of peri-implantitis between years 1 and 7 and between years 7 and 13 were 26.2% and 7.1% for AT implants, and 30.4% and 11.5% for NB implants (NS). A history of periodontitis was a risk for future incidence of peri-implantitis (Likelihood ratio: 4.1, 95% CI: 2.0, 8.4, p < 0.001). Subjects with a history of systemic disease had a higher incidence of peri-implantitis (p < 0.05). Conclusions No difference in the incidence of peri-implantitis over a period of 13 years as an effect implant surface and design was found. Bone loss during the first 7 years after implant installation was greater than thereafter. Microbiological information at year 7 did not predict incidence of peri-implantitis at year 13. Subjects with a previous history of periodontitis and with systemic disease were at higher risk for future incidence of peri-implantitis.

Objectives Bone formation and maintenance around implants placed immediately after tooth extraction may be affected by implant surface treatment and compromise long-term esthetic results. This study morphometrically evaluated buccal bone loss and bone-to-implant contact (BIC) of four implant systems placed immediately after tooth extraction in a dog model. Material and Methods The premolars of eight beagle dogs were bilaterally extracted with a full-thickness flap, and root-form dental implants were placed on the root extraction socket. Implants (n = 16 each) with different surface treatments were placed from sites 1 to 4 and alternated between animals to allow evaluation of the same number of implants at sites and evaluation time points. Implant surface treatments were as follows: anodized, discrete crystalline deposition, SLActive, and microblasted. The left and right side provided implants that stayed for 2 and 4 weeks, respectively. Submerged healing was allowed and bone-to-implant contact (BIC) and buccal bone loss were morphometrically measured. Linear mixed models (P

Objectives Bonding of restorative materials in dentistry may be enhanced significantly by the use of engineered silane blends. Trialkoxy silane esters have the unique property to unite dissimilar materials. Silanization is required when cementing the crown or the abutment on a silica-coated zirconia subgingival implant surface with an organophosphate-resin-composite. In this laboratory study, we report about our latest findings in laboratory experiments on experimental silane primers. Material and methods In the adhesion promotion of resin-composites to the zirconia implant surface using four experimental blends, a so-called "Novel Silane System", consisting of a functional silane (3-acryloxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane and 3-styrylethyltrimethoxysilane) and a cross-linking silane, bis-1,2-(triethoxysilyl)ethane, were mixed in a water/ethanol solvent system with a pH of 4.5, and applied onto silica-coated planar zirconia specimens. A resin composite stub (with a bonding area diameter of 2.0 mm) was cemented using a polypropylene mold. Initial shear bond strengths (baseline values) were measured of specimens after dry storage and after thermo-cycling between 5.0 ± 0.5°C and 55.0 ± 0.5°C. As the control was a dental prehydrolyzed ready-to-use silane product. Results All the values for shear bond strength test were significantly increased (P > 0.05) during thermo-cycling. The results showed that the highest shear bond strength was obtained for 3-glycidoxypropyltrimethoxysilane +bis-1,2-(triethoxysilyl)ethane in both dry and thermo-cycled conditions with stress values of 11.04 and 14.89 MPa, respectively. The lowest values were found for the control silane in both dry and thermo-cycled conditions with stress values of 4.5 and 6.5 MPa, respectively. Conclusion Silanization with a novel silane system yielded significantly higher shear bond strength than the control silane (a 3-methacryloxypropyltrimethoxysilane containing). We have introduced a bonding system that might be useful and durable in implant dentistry.

Objective This study aimed at identifying the ideal concentration of a biofunctional surface coating of dental implants with a synthetic peptide (P-15). In a previous study, P-15 was shown to enhance osseointegration parameters. Material and methods Implants (modified ANKYLOS® A8; FRIADENT Plus® surface) with five different concentrations (0–400 μg/ml) of a P-15 coating as well as uncoated controls were inserted in the frontal bone of 45 adult domestic pigs. The histomorphometric and microradiographic findings for the coated implants were compared to those for the uncoated ones after 7, 14, and 30 days. Results No significant differences were observed comparing the peri-implant bone density between the coated and uncoated implants The bone-to-implant contact, as the primary histological parameter for osseointegration, showed high rates for all surfaces investigated (between 73.3 ± 17.9% for the control and 81.9 ± 15.2% for P15 20 μg/ml after 30 days). Conclusions No significant benefit on osseointegration of a biofunctional P-15 coating of dental implants could be displayed in the present study.

Background: Thin bioceramic coatings have been regarded as potential substitutes for plasma-sprayed hydroxyapatite coatings. Purpose: This study tested the hypothesis that a thin bioactive ceramic coating deposition on an alumina-blasted/acid-etched (AB/AE) surface would positively affect the biomechanical fixation and bone-to-implant contact (BIC) of plateau root form implants. Materials and Methods: Implants of two different lengths (i.e., 4.5 × 11 mm long, n = 36) and 4.5 × 6 mm (short, n = 36) and two different surfaces, that is, control (AB/AE) and test (AB/AE + 300 – 500 nm bioactive ceramic coating), were placed in the proximal tibiae of six beagle dogs. The implants were retrieved for analyses 2 and 4 weeks after placement. The implants in bone specimens were subjected to torque loads until a 10% drop of the maximum torque was recorded. The specimens were evaluated under optical microscopy for bone morphology and percent BIC. Statistical analysis was performed by a generalized linear mixed effects analysis of variance model and statistical significance set at p