a retrospective study in 1200 edentulous jaws

This retrospective study analyzed implant survival of immediate implant-supported fixed complete denture (IFCD) treatment options (TOs) based on the level of alveolar atrophy (CC). Records of 882 patients receiving a total of 6042 implants at one private referral clinic between 2004 and 2020 were considered. The mean follow-up period was 3.8 ± 2.7 years. Cumulative implant survival rates (CSRs) were analyzed as a function of CCs and TOs according to Mantel-Haenszel and Mantel-Cox. Hazard risk ratios for implant loss were compared using Cox regression. Confounding factors were identified using mixed Cox regression models. The 2- and 5-year CSRs were 98.2% and 97.9%, respectively. Maxillary 2- and 5-year CSRs were lower (97.7% and 97.3%) compared to mandibular CSRs (99.8% and 98.6%) (p = 0.030 and 0.0020, respectively). The CC did not influence CSRs of IFCDs in the mandible (p = 0.1483 and 0.3014, respectively) but only in the maxilla (p = 0.0147 and 0.0111), where CSRs decreased with increasing atrophy. TOs did not statistically differ in terms of survival rate for a given level of alveolar atrophy. The adaption of IFCD treatments to the level of atrophy and patient-specific risk factors can result in high CSRs, even at different levels of bone atrophy.info:eu-repo/semantics/publishedVersio

Guided Bone Regeneration in the Edentulous Atrophic Maxilla Using Deproteinized Bovine Bone Mineral (DBBM) Combined with Platelet-Rich Fibrin (PRF)—A Prospective Study

Background: Bone regeneration procedures represent a major challenge in oral surgery. This study aimed to evaluate a composite PRF/particulate xenograft in guided bone regeneration. Methods: Edentulous patients with horizontal ridge deficiencies in the anterior maxilla and candidates to an immediate-loading full-arch rehabilitation were included. Horizontal linear measurements indicating bone gain were assessed from computer beam computer tomography (CBCT) scans obtained at pre-surgery, post-surgery, and the 12-month follow-up. Mean bone values were presented as mean ± 95% CI. Non-parametric tests were used as appropriate, and the effect size was calculated with Cohen’s d repeated measures. Results: Eighteen patients were rehabilitated with 72 implants. The mean horizontal bone width was 4.47 [4.13–4.80] mm pre-surgically, 9.25 [8.76–9.75] mm post-surgically, and 7.71 [7.28–8.14] mm 12 months after. Conclusions: PRF associated with a xenograft seems to promote an effective horizontal bone gain. Randomized clinical trials are needed to confirm the benefits of this surgical approach

Ceramic-veneered zirconia frameworks in full-arch implant rehabilitations: A 6-month to 5-year retrospective cohort study

Purpose: This was a retrospective cohort study designed to evaluate the clinical performance of ceramicveneered zirconia frameworks. Materials and Methods: Patients were recruited according to defined inclusion criteria. All patients were checked every 4 months from the time of definitive rehabilitation. At the end of 2013, all patients were rescheduled and rechecked for study purposes. The restorative procedures assessment was performed by previously established methods. The primary outcomes were the survival and success rates of the prosthesis. Descriptive statistics were used for the patient's demographics, implant distribution, and occurrence of complications. To study the survival and success of the prostheses, a Cox Regression analysis was used with a model constructed in a forward conditional stepwise mode. Predictive variables were included in the model, and adjusted survival curves were obtained for each outcome. Results: From 2008 to 2013, 75 patients were rehabilitated with 92 implant-supported, screw-retained, full-arch ceramic-veneered zirconia framework rehabilitations. The range of follow-up was between 6 months and 5 years. From the 92 full implant-supported screw-retained full-arch rehabilitations, Cox regression analysis indicated that within a 5-year time frame, the probability of framework fracture, major chipping, minor chipping, or any of the former combined to occur was 17.6%, 46.5%, 69.2%, and 90.5%, respectively. Conclusion: Results suggest zirconia as a suitable material for framework structure in implant-supported, full-arch rehabilitations. However, it experiences a high incidence of technical complications, mainly due to ceramic chipping. Further clinical studies should aim to ascertain the effects of clinical features and manufacturing procedures on the survival rates of these prostheses. © 2016 by Quintessence Publishing Co Inc.Sin financiación2.263 JCR (2016) Q1, 22/90 Dentistry, Oral Surgery and MedicineUE

Effect of cross‐linked vs non‐cross‐linked collagen membranes on bone: A systematic review

The aim of this study was to conduct a systematic review to compare the clinical outcomes of two different resorbable collagen membranes in terms of regenerated bone volume, postoperative complications and membrane degradation during bone regeneration procedures. Randomized controlled trials (RCT) or controlled trials (CT) that compared both techniques were reviewed on four electronic databases up to December 2015, a manual search was performed on the bibliography of the collected articles and the authors were contacted for additional references if undetected on the electronic and manual search. Membrane exposure was evaluated as a dichotomous outcome and the statistical unit was the membrane. The results were presented as relative risk (RR) with a 95% confidence interval. Eight RCTs and one CT were included in this study. The majority of the studies depicted a bone augmentation area, which ranged from 46.15% to 94.6% for the non‐cross‐link membranes and from 44% to 92.6% for the cross‐link membranes at the 4‐6 month re‐entry surgery. From a total of 289 patients, a forest plot concerning the membrane exposure was constructed using the obtained RR of the included studies. The overall RR was 1.43 (95% CI: 0.85‐2.39) with no statistically significant differences between the two groups, although with a marginal tendency towards higher exposure in the cross‐link membrane group. This systematic review suggests the different membranes present themselves as appropriate for bone regeneration procedures, although cross‐link membranes present higher rates of postoperative complications. However, more RCT with higher sample sizes are needed to evaluate the different membranes. The suggested lack of clinical differences between the compared membranes suggest that further cost‐benefit ratio, tissue integration and postoperative complication oriented studies should be performed so that clinicians can take a patient‐centred, evidence‐based decision.Sin financiación2.878 SJR (2017) Q1, 14/91 Dentistry, Oral Surgery & MedicineUE

Short implants versus bone grafting and standard-length implants placement: A systematic review

The aim of this study was to conduct a systematic review to compare the survival rates between short implants (length < 10 mm) versus standard-length implants (≥ 10 mm) inserted in grafted bone. As secondary outcomes, marginal bone loss and survival rates of the implant supported prostheses were also analysed.Sin financiación2.453 JCR (2018) Q1, 21/91 Dentistry, Oral Surgery & Medicine0.993 SJR (2018) Q1, 15/146 Dentistry (miscellaneous)No data IDR 2018UE

Quality assessment of systematic reviews on vertical bone regeneration

The aim of this study was to evaluate and compare the quality of systematic reviews of vertical bone regeneration techniques, using two quality-assessment tools (AMSTAR and ROBIS). An electronic literature search was conducted to identify systematic reviews or meta-analyses that would evaluate at least one of the following outcomes: implant survival, success rates, complications or bone gain after vertical ridge augmentation. Methodological quality assessment was performed by two independent evaluators. Results were compared between reviewers, and reliability measures were calculated using the Holsti’s method® and Cohen’s kappa. Seventeen systematic reviews were included, of which seven presented meta-analysis. Mean ±95% confidence interval AMSTAR score was 6.35 [4.74;7.97], with higher scores being correlated with a smaller risk of bias (Pearson’s correlation coefficient = −0.84; P < 0.01). Cohen’s inter-examiner kappa showed substantial agreement for both checklists. From the available evidence, we ascertained that, regardless of the technique used, it is possible to obtain vertical bone gains. Implant success in regenerated areas was similar to implants placed in pristine bone with results equating between 61.5% and 100% with guided bone regeneration being considered the most predictable technique regarding bone stability, while distraction osteogenesis achieved the biggest bone gains with the highest risk of possible complications.Sin financiación2.068 JCR (2019) Q2, 33/91 Dentistry, Oral Surgery & Medicine1.020 SJR (2019) Q1, 9/49 Oral SurgeryNo data IDR 2018UE

The use of titanium dental implants versus zirconium dioxide dental implants in esthetic zone. Systematic review

Background: The use of zirconium dental implants for esthetic purposes seems to have a promising future due to similar survival rates to titanium implants. Other added mentioned proprieties are white color, the small level of bacterial adherence and the high resistance of the material. Aim/Hypothesis: The main aim of this systematic review was to evaluate the zirconium oxide implants success and survival rates (ZrO2) versus the titanium implants (Ti) in the esthetic area. Material and Methods: This Systematic review was registered at PROSPERO with the reference CRD42015019546. Clinical trials that evaluated zirconium oxide implants were searched in seven electronic databases (PubMed, Lilacs, Science Direct, Cochrane Collaboration, Evidence Based Dentistry (EBD), Journal of Evidence-Based Dental Practice (JEBDP), NHS Evidence) till November 2016 and were included according to pre-established inclusion criteria. A manual search was performed on the bibliography of the collected articles, and the authors were contacted for additional references. Success and survival rate for titanium implants (Ti) was compared with the zirconium oxide implants success and survival rate (ZrO2). The quality of the included articles was evaluated using the Critical Appraisal Skills Programme (CASP) criteria, thus being analysed at both study and outcome level. Results: Seventeen articles were included and the results obtained after calculating the data from each study, in which the zirconium oxide dental implants (ZrO2) location (maxilla or mandible, anterior or posterior) is described. Number of patients: 1057. Number of implants of ZrO2: 1916. Survival: 95%. Follow-up Mean: 32 months (2.6 years). In order to analyze the information about the esthetic area, the studies which did not describe the placement of the zirconium oxide implants in the anterior area (ZrO2) were discarded, only implants placed from 14 to 24 and 34 to 44 (esthetic area) were accounted for: 486 ZrO2 implants, 94% survival, 29 months of follow-up (2.4 years). Of the included studies only two were randomized controlled trials, twelve prospective trials and three retrospective studies. Several methodological limitations on the collected articles and debated in this review. The overall survival rate of the zirconium oxide implants of one and two pieces resulted in 95%. Conclusions and Clinical Implications: Although the available scientific evidence base is and at considerable risk of bias, from the available data it is possible to conclude that zirconia dental implants could be used in esthetic zone with 94% survival. The different study designs and methodology make difficult to present an overall conclusion regarding the efficacy of ZrO2 implants in maintaining crestal bone levels and peri-implant soft tissue health. Further long-term, randomized controlled trials with a standard methodology are needed.Sin financiación4.305 JCR (2017) Q1, 4/91 Dentistry, Oral Surgery & Medicine, 8/78 Engineering, BiomedicalUE

Peri-implant cell response on groove and pore-textured zirconia surfaces

Objectives: This study aimed to assess the independent influence of grooves and pores texturized by milling on gold-standard zirconia implant surfaces. Methods: Milled groove and pore textured with equivalent width, depth, and spacing on zirconia discs were produced using press and sintering techniques. All samples were sandblasted and acid-etched (SBAE), and untextured discs were used as controls. Osteoblasts and fibroblasts were cultured on discs for 14 days. Field emission gun-scanning electron microscopy (FEG-SEM) was used to observe cellular adhesion and morphology. Cell viability and proliferation assays were performed. Additionally, alkaline phosphatase activity, collagen type I, and osteopontin were evaluated at pre-defined time points. Results are presented as mean and standard deviation (SD), group comparisons were tested using one-way ANOVA (Tukey's post-hoc), and significance was set at P < 0.05. Results: FEG-SEM images revealed cellular adhesion at 24 h in all samples with differences in distribution. Although both cell lines showed increased cell viability and differentiation cell markers such as collagen and osteopontin over time, statistically significant differences between groups were found in none of the quantitative study variables (P > 0.05). Conclusion: The results suggest similar cellular behavior between different patterns with similar dimensions and between them and microtopography by SBAE protocol currently used as the gold-standard for zirconia dental implants. The addition of pore and groove microtextures to the gold-standard zirconia dental implant surfaces treated with SBAE does not seem to be an asset in the cellular behavior of the hard and soft tissue cells.This work was supported by FCT project POCI-01-0145-FEDER030498 e Portugal, by FEDER funds through the COMPETE 2020 e Programa Operacional Competitividade e Internacionalização(POCI)

Laser surface treatment on Yttria-stabilized zirconia dental implants: influence on cell behavior

Version of Record online: 18 July 2021Yttria-stabilized zirconia (YSZ) is being proposed as an alternative material to Titanium for dental implants due to its aesthetic and biocompatibility properties. However, is it yet to define the optimal surface treatment to improve YSZ bioactivy. Texturization is a promising approach, but the biological role of patterned YSZ surfaces in cell cultures is yet to be determined. Thus, cellular behavior of osteoblasts and fibroblasts in contact with groove-texturized YSZ surfaces was investigated. YSZ discs were groove-textured by conventional milling and Nd:YAG laser. All samples including control were sandblasted and acid-etched. Human osteoblasts and fibroblasts were cultured on discs for 14 days. Morphology and cellular adhesion were observed. Cell viability, interleukin-1 beta, osteopontin, collagen type I prodution, alkaline phosphatase activity, and interleukin-8 were measured. YSZ texturization by conventional milling improved osteoblasts viability and differentiation when compared to laser texturization. Fibroblasts behavior did not seem to be influenced by the texturing technique. Compared to sandblasting and acid etching currently used as gold standard for zirconia dental implants no superiority of macrotexturization was found.This study was supported by FCT project POCI-01-0145-FEDER-030498-Portugal, by FEDER funds through the COMPETE 2020-Programa Operacional Competitividade e Internacionalizacao (POCI)

Bioactive-enhanced polyetheretherketone dental implant materials: Mechanical characterization and cellular responses

The aim of this study was to characterize the mechanical properties of a bioactive-modified polyetheretherketone (PEEK) manufacturing approach for dental implants and to compare the in vitro biological behavior with titanium alloy (Ti6Al4V) as the reference. PEEK, PEEK with 5% hydroxyapatite (HA), PEEK with 5% beta-tricalcium phosphate (beta TCP), and Ti6Al4V discs were produced using hot pressing technology to create a functionally graded material (FGM). Surface roughness values (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness tests were performed. Human osteoblasts and gingival fibroblasts bioactivity was evaluated by a resazurin-based method, alkaline phosphatase activity (ALP), and confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts. Morphology and cellular adhesion were confirmed using field emission gun-scanning electron microscopy (FEG-SEM). Group comparisons were tested using analysis of variance (Tukey post hoc test), alpha=.05. All groups presented similar roughness values (P>.05). Ti6Al4V group was found to have the highest contact angle (P.05); however, the mean values in the Ti6Al4V group were significantly higher when compared with those of the other groups (P<.05). Cell viability and proliferation of osteoblast and fibroblast cells were higher in the PEEK group (P<.05). PEEK-bTCP showed the highest significant ALP activity over time (P<.05 at 14 days of culture). An enhanced bone and soft-tissue cell behavior on pure PEEK was obtained to the gold standard (Ti6Al4V) with equivalent roughness. The results substantiate the potential role of chemical composition rather than physical properties of materials in biological responses. The addition of 5% HA or beta TCP by FGM did not enhance PEEK mechanical properties or periodontal cell behavior.The statistical methodology and analysis were reviewed by an independent statistician (Joana Fialho, PhD, adjunct professor, Escola Superior de Tecnologia e Gestao de Viseu, Centro de Estudos em Educac ao, Tecnologias e Saude, Viseu, Portugal). The support of Professor Rui Malho ' (Faculty of Science, Universidade de Lisboa) in obtaining confocal laser microscopy images is highly appreciated. We would also like to thank Professor Helena Raposo Fernandes and Professor Pedro Gomes (Faculty of Dental Medicine, Universidade do Porto) for their invaluable support in setting up cell experiments. This work was supported by FCT project NORTE-01-0145-FEDER000018 -Portugal, by FCT reference projects PTDC/EME-EME/30498/2017 and UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 -Programa Operacional Competitividade e Internacionalizacao (POCI) with the reference project POCI-010145-FEDER-006941, and by Coordination of Improvement of Higher Level Personnel -CAPES -Brazil, PDSE 99999.006407/2015-03 Process