Comparative evidence of different surgical techniques for the management of vertical alveolar ridge defects in terms of complications and efficacy: A systematic review and network meta-analysis

Aim: To systematically appraise the available evidence on vertical ridge augmentation (VRA) techniques and estimate a treatment-based ranking on the incidence of complications as well as their clinical effectiveness. // Materials and Methods: Searches were conducted in six databases to identify randomized clinical trials comparing VRA techniques up to November 2022. The incidence of complications (primary) and of early, major, surgical and intra-operative complications, vertical bone gain (VBG), marginal bone loss, need for additional grafting, implant success/survival, and patient-reported outcome measures (secondary) were chosen as outcomes. Direct and indirect effects and treatment ranking were estimated using Bayesian pair-wise and network meta-analysis (NMA) models. // Results: Thirty-two trials (761 participants and 943 defects) were included. Five NMA models involving nine treatment groups were created: onlay, inlay, dense-polytetrafluoroethylene, expanded-polytetrafluoroethylene, titanium, resorbable membranes, distraction osteogenesis, tissue expansion and short implants. Compared with short implants, statistically significant higher odds ratios of healing complications were confirmed for all groups except those with resorbable membranes (odds ratio 5.4, 95% credible interval 0.92–29.14). The latter group, however, ranked last in clinical VBG. // Conclusions: VRA techniques achieving greater VBG are also associated with higher incidence of healing complications. Guided bone regeneration techniques using non-resorbable membranes yield the most favourable results in relation to VBG and complications

XENOGENEIC DERMAL MATRIX VERSUS AUTOLOGOUS CONNECTIVE TISSUE GRAFT VERSUS NO GRAFT AT ABUTMENT CONNECTION FOR IMPROVING AESTHETICS: 6-MONTH OUTCOMES OF A RANDOMISED CONTROLLED TRIAL

OBJECTIVES. The aim of this multicentre randomised controlled trial was to evaluate the efficacy of a xenogeneic dermal matrix in widening keratinised peri-implant tissues du-ring second-stage surgery, and to compare it to both autologous connective tissue graft and a control group with no augmentation. MATERIAL AND METHODS. Patients requiring an increase in keratinised gingiva width were enrolled by four university/dental practices and randomised into three different groups for grafting procedures at the implant uncovering stage: either xenogeneic dermal matrix (Group X), autologous connective tissue graft (Group A) or no graft (control, Group C). The primary outcomes were width of keratinised tissue and facial soft tissue levels, evaluated at three different time points (T0, implant uncovering stage; T1 and T2, six weeks and six months after surgery, respectively). Secondary outcomes were: implant failure, complications, marginal bone loss, papilla index, facial soft tissue level, pink esthetic score, and aesthetic assessment by patients. RESULTS. Thirty-six patients, with one implant per patient, were enrolled at two centres (18 at each centre): 12 for control, 12 for xenogeneic dermal matrix and 12 for autologous tissue graft. Three patients dropped out and two patients from the autologous group had implant failures. No complications were recorded. After six months, the width of keratini-sed tissue increased by 0.16 ± 1.01 (P = 0.79), 1.05 ± 0.76 (P = 0.01) and 0.80 ± 1.73 mm (P = 0.28), and facial soft tissue level was-0.95 ± 0.85 (P = 0.04), 0.32 ± 0.57 (P = 0.15) and 0.35 ± 0.79 mm (P = 0.30) respectively in Groups C, X and A groups. Between-group analysis showed that, with respect to control, only facial soft tissue level (1.31 mm, P = 0.01) and width of keratinised mucosa (2.43 mm, P = 0.01) outcomes in the autologous graft group were statistically significant at T2. Mean marginal bone loss between T0-T2 was-0.4 ± 0.4mm, with no differences between groups. Pink aesthetic score showed no significant differences between groups, being 0.89 for A-C (P = 0.41), 0.88 for A–X (P = 0.63) and 0.72 for X-C (P = 0.88). Patient’s aesthetic satisfaction (Visual Analogue Scale) was 92.2 ± 8.4, 93.8 ± 7.7, 97.2 ± 3.0, for Groups C, X and A, respectively. Between the two dental centres, only facial soft tissue level at T0–T2 was significantly different, by 0.67 ± 0.62 mm (P = 0.03). CONCLUSIONS. After six months, autologous connective tissue graft yielded a significant gain in facial soft tissue levels and width of keratinised mucosa, as compared to the control group (no graft)

Genetic variability and history of a native Finnish horse breed

Background: The Finnhorse was established as a breed more than 110 years ago by combining local Finnish landraces. Since its foundation, the breed has experienced both strong directional selection, especially for size and colour, and severe population bottlenecks that are connected with its initial foundation and subsequent changes in agricultural and forestry practices. Here, we used sequences of the mitochondrial control region and genomic single nucleotide polymorphisms (SNPs) to estimate the genetic diversity and differentiation of the four Finnhorse breeding sections: trotters, pony-sized horses, draught horses and riding horses. Furthermore, we estimated inbreeding and effective population sizes over time to infer the history of this breed. Results: We found a high level of mitochondrial genetic variation and identified 16 of the 18 haplogroups described in present-day horses. Interestingly, one of these detected haplogroups was previously reported only in the Przewalski’s horse. Female effective population sizes were in the thousands, but declines were evident at the times when the breed and its breeding sections were founded. By contrast, nuclear variation and effective population sizes were small (approximately 50). Nevertheless, inbreeding in Finnhorses was lower than in many other horse breeds. Based on nuclear SNP data, genetic differentiation among the four breeding sections was strongest between the draught horses and the three other sections (FST=0.007–0.018), whereas based on mitochondrial DNA data, it was strongest between the trotters and the pony-sized and riding horses (ΦST= 0.054–0.068). Conclusions: The existence of a Przewalski’s horse haplogroup in the Finnhorse provides new insights into the domestication of the horse, and this finding supports previous suggestions of a close relationship between the Finnhorse and eastern primitive breeds. The high level of mitochondrial DNA variation in the Finnhorse supports its domestication from a large number of mares but also reflects that its founding depended on many local landraces. Although inbreeding in Finnhorses was lower than in many other horse breeds, the small nuclear effective popula- tion sizes of each of its breeding sections can be considered as a warning sign, which warrants changes in breeding practices.Peer reviewe

Immediate Occlusal Loading of One-Piece Zirconia Implants: Five-Year Radiographic and Clinical Evaluation

PURPOSE: To evaluate radiographic and clinical outcomes of immediate occlusally loaded one-piece zirconia implants after 5 years of follow-up. MATERIALS AND METHODS: This longitudinal clinical investigation included patients older than 18 years, in need of implant-supported single-unit dental rehabilitations. One-piece zirconia in healed and postextraction sites and immediately restored with provisional crowns in light occlusal contact. Definitive zirconia-ceramic restorations were delivered 3 to 4 months after surgery. Primary estimated outcomes were implant survival and success. Periapical radiographs were taken at implant insertion (T0), after 1 year (T1), and after 5 years (T2) to assess marginal bone loss (MBL). Probing depth (PD), modified Bleeding Index (mBI), modified Plaque Index (mPI), and gingival recession (REC) were also measured repeatedly for implants and reference teeth. Changes in parameters over time were assessed using the Wilcoxon signed rank test. In addition, multilevel mixed effects linear and logistic regression models were fitted to take into account within-subject correlations and baseline values. RESULTS: Thirty-two implants were inserted in postextraction and healed sites (n = 16 of each) in 17 patients. One immediate implant was lost after 3 months, and one patient with one implant dropped out after T1. Therefore, the cumulative survival rates were 96.9% at T1 and 96.8% at T2 (4.3 to 6 years). No significant differences were observed in mean MBL between immediate and delayed implants at either T1 or T2. Moreover, different baseline parameters (sex, arch, implant location, smoking habits, grafting) did not show any influence on MBL at either time. In general, for all clinical parameters (PD, mBI, mPI, REC), implants seemed to perform similar to if not better than natural teeth. CONCLUSION: Radiographic and clinical evaluations after 5 years showed satisfactory amounts of MBL and acceptable soft tissue health

The physiological linkage between molar inclination and dental macrowear pattern

Objectives: Exact symmetry and perfect balance between opposite jaw halves, as well as between antagonistic teeth, is not frequently observed in natural masticatory systems. Research results show that asymmetry in our body, skull, and jaws is often related to genetic, epigenetic, environmental and individual ontogenetic factors. Our study aims to provide evidence for a significant link between masticatory asymmetry and occlusal contact between antagonist teeth by testing the hypothesis that tooth inclination is one of the mechanisms driving distribution of wear in masticatory phases in addition to dietary and cultural habits. Materials and Methods: The present work investigates the relationship between dental macrowear patterns and tooth inclinations on a sample of complete maxillary and mandibular 3D models of dental arches from 19 young and adult Yuendumu Aboriginal individuals. The analysis was carried out on first molars (M1) from all quadrants. Occlusal Fingerprint Analysis was used for the quantification of macrowear patterns, and 2D cross-sectional geometric analysis was carried out to investigate asymmetry in dental arches. Results: The asymmetry is highly variable on both arches, and it is associated with differences in the inclination of upper M1 crowns. Each molar has variable inclination (buccal/lingual) which influence tooth to tooth contact, producing greater or lesser variation in wear pattern. Interindividual variability of morphological variation of the occlusal relationship has to be considered in macrowear analysis. Discussion: Our results suggest that overall asymmetry in the masticatory apparatus in modern humans affects occlusal contact areas between antagonist teeth influencing macrowear and chewing efficiency during ontogeny

In Vitro Comparison of Bonding Effectiveness of Different Adhesive Strategies.

Abstract Background: To date there is not a material considered ideal for the lased dentin. Objective: To compare the bond strength to human lased dentin of self-etch and etch-and-rinse adhesive systems, a self-adhesive resin composite and a glass-ionomer cement. Methods: Forty human molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin. The occlusal surface of each slab was polished by SiC paper (P600) for 10 s. Then an half part of dentin slabs was randomly selected for receiving treatment with 2.94 µm Er:YAG laser (DEKA, Smart 2940D Plus) with 10 Hz at 100 mJ, pulse duration of 230 µs with contact tip. Dentin slabs were randomly divided into four groups (n = 10). Six conical frustum-shaped build-ups were constructed on the occlusal surface of each dentin slab using bonding agents (OptiBond Solo Plus Group 1; OptiBond All-in-one Group 2) combined with a resin composite (Premise Flow), self-adhesive resin composites (Vertise Flow Group 3) and a glass-ionomer cement (Ketac-Fil Group 4). Specimens were subjected to µSBS test. Data were analyzed by a mixed model and Tukey's test. Results: Measured bond strengths were (mean ± standard deviation): 20.8 ± 5.5 MPa (laser treatment) and 15.6 ± 4.5 MPa (SiC paper) for Group 1, 18.9 ± 5.3 MPa (laser treatment) and 14.0 ± 4.3 MPa (SiC paper) for Group 2, 7.9 ± 2.8 MPa (laser treatment) and 4.3 ± 2.2 MPa (SiC paper) for Group 3, 4.7 ± 1.9 MPa (laser treatment) and 2.6 ± 1.2 MPa (SiC paper) for Group 4. The inferential analysis showed that the dentin laser treatment significantly affected the bond strength within each individual group. On dentin treated with laser the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with D. S. Russo et al. 2 self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Similarly, on dentin treated with SiC paper the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Conclusion: Er:YAG laser treatment has increased the shear bond strength of all the adhesive materials used