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In cases of severely compromised teeth, dental practitioners are confronted with the therapeutic decision of whether to restore a tooth or replace it with an implant. Comparative scientific evidence on patient perception of both treatment approaches is scarce. The subject of this prospective clinical study was to compare oral health-related quality of life (OHRQoL) between two treatment groups: restoration of severely destroyed teeth after orthodontic extrusion (FOE) versus tooth extraction and implant-supported single crown restoration (ISC). A self-selected trial was performed with 21 patients per group. OHRQoL was assessed with the aid of the Oral Health Impact Profile (OHIP-G49) at different time intervals: before treatment (T1), after treatment (T2), after restoration (T3) and at recall (T4). Overall, OHIP scores improved from baseline to follow-up for both concepts with no significant differences between groups. There were no significant differences in subscales between FOE and ISC at T1, T3 and T4. In terms of functional limitations (p = 0.003) and physical disability (p = 0.021), patients in the FOE group temporarily exhibited lower OHRQoL at T2 in comparison to the ISC group. However, at baseline, after final restoration and at recall, the study demonstrates the same level of OHRQoL for both treatment concepts.

SHANK2 mutations have been identified in individuals with neurodevelopmental disorders, including intellectual disability and autism spectrum disorders (ASD). Using CRISPR/Cas9 genome editing, we obtained SH-SY5Y cell lines with frameshift mutations on one or both SHANK2 alleles. We investigated the effects of the different SHANK2 mutations on cell morphology, cell proliferation and differentiation potential during early neuronal differentiation. All mutant cell lines showed impaired neuronal differentiation marker expression. Cells with bi-allelic SHANK2 mutations revealed diminished apoptosis and increased proliferation, as well as decreased neurite outgrowth during early neuronal differentiation. Bi-allelic SHANK2 mutations resulted in an increase in p-AKT levels, suggesting that SHANK2 mutations impair downstream signaling of tyrosine kinase receptors. Additionally, cells with bi-allelic SHANK2 mutations had lower amyloid precursor protein (APP) expression compared to controls, suggesting a molecular link between SHANK2 and APP. Together, we can show that frameshift mutations on one or both SHANK2 alleles lead to an alteration of neuronal differentiation in SH-SY5Y cells, characterized by changes in cell growth and pre- and postsynaptic protein expression. We also provide first evidence that downstream signaling of tyrosine kinase receptors and amyloid precursor protein expression are affected.

In cases of severely compromised teeth, dental practitioners are confronted with the therapeutic decision of whether to restore a tooth or replace it with an implant. Comparative scientific evidence on patient perception of both treatment approaches is scarce. The subject of this prospective clinical study was to compare oral health-related quality of life (OHRQoL) between two treatment groups: restoration of severely destroyed teeth after orthodontic extrusion (FOE) versus tooth extraction and implant-supported single crown restoration (ISC). A self-selected trial was performed with 21 patients per group. OHRQoL was assessed with the aid of the Oral Health Impact Profile (OHIP-G49) at different time intervals: before treatment (T1), after treatment (T2), after restoration (T3) and at recall (T4). Overall, OHIP scores improved from baseline to follow-up for both concepts with no significant differences between groups. There were no significant differences in subscales between FOE and ISC at T1, T3 and T4. In terms of functional limitations (p = 0.003) and physical disability (p = 0.021), patients in the FOE group temporarily exhibited lower OHRQoL at T2 in comparison to the ISC group. However, at baseline, after final restoration and at recall, the study demonstrates the same level of OHRQoL for both treatment concepts.

Various protocols are available to preclinically assess the fracture resistance of zirconia oral implants. The objective of the present review was to determine the impact of different treatments (dynamic loading, hydrothermal aging) and implant features (e.g., material, design or manufacturing) on the fracture resistance of zirconia implants. An electronic screening of two databases (MEDLINE/Pubmed, Embase) was performed. Investigations including > 5 screw-shaped implants providing information to calculate the bending moment at the time point of static loading to fracture were considered. Data was extracted and meta-analyses were conducted using multilevel mixed-effects generalized linear models (GLMs). The Šidák method was used to correct for multiple testing. The initial search resulted in 1864 articles, and finally 19 investigations loading 731 zirconia implants to fracture were analyzed. In general, fracture resistance was affected by the implant design (1-piece > 2-piece, p = 0.004), material (alumina-toughened zirconia/ATZ > yttria-stabilized tetragonal zirconia polycrystal/Y-TZP, p = 0.002) and abutment preparation (untouched > modified/grinded, p < 0.001). In case of 2-piece implants, the amount of dynamic loading cycles prior to static loading (p < 0.001) or anatomical crown supply (p < 0.001) negatively affected the outcome. No impact was found for hydrothermal aging. Heterogeneous findings of the present review highlight the importance of thoroughly and individually evaluating the fracture resistance of every zirconia implant system prior to market release.

Objective To assess the survival and technical complication rate of partial and full-arch all-ceramic implant-supported fixed dental prostheses (P-FDP/FA-FDP) and supporting implants. Materials and methods An electronic search through three databases (MEDLINE/Pubmed, Cochrane Library, Embase) was conducted to identify relevant clinical studies with an observation period of at least 12 months, including ≥15 patients. Reconstruction and implant survival rates, technical complications and confounding variables such as processed/installed materials, retention mode and location in the mouth were obtained. Failure and complication rates were analyzed using standard Poisson regression models to calculate 5-year survival and complication estimates. Results A total of five studies for the P-FDP group and seven studies for the FA-FDP group were included, throughout evaluating veneered zirconia reconstructions. In the P-FDP group, reconstructions were located in posterior regions. Meta-analysis indicated survival estimates on the reconstruction level of 98.3% and 97.7% for P- and FA-FDPs after 5 years. However, chipping of the veneering ceramic was frequent, resulting in estimated 5-year complication rates of 22.8% (P-FDPs) and 34.8% (FA-FDPs). Five-year survival estimates of implants supporting P-FDPs and FA-FDPs of 98.5% and 99.4% were calculated, respectively. Including a total of 540 FDPs, one screw-loosening and 11 de-cementations were reported. Confounding variables were not found to have a significant influence on survival and complication rates. Conclusions All-ceramic implant-supported P- and FA-FDPs comprising veneered zirconia frameworks showed high survival but clinically inacceptable fracture rates of the veneering ceramic. Their suitability with regard to this indication and a successful long-term outcome needs to be further evaluated.

Introduction This is the first long-term randomized controlled trial to evaluate dentin-like glass fiber posts (GFPs) compared with rather rigid titanium posts (TPs) for post-endodontic restoration of severely damaged endodontically treated teeth with 2 or fewer remaining cavity walls. Methods Ninety-one subjects in need of post-endodontic restorations were randomly assigned to receive either a tapered GFP ( n = 45) or TP ( n = 46). Posts were adhesively luted by using self-adhesive resin cement, followed by composite core build-up and preparation of 2-mm ferrule design. Primary end point was loss of restoration for any reason. Kaplan-Meier curves were constructed, and log-rank test was calculated ( P Results After a follow-up of 132 months, 17 GFP and 20 TP restorations survived, and 19 failed (12 GFP, 7 TP). Failure modes for GFP were root fracture ( n = 4), core fracture ( n = 1), secondary caries ( n = 1), endodontic failure ( n = 2), extraction because of tooth mobility grade III associated with insufficient design of removable partial denture ( n = 1), tooth fracture ( n = 1), and changes in treatment plan ( n = 2); failure modes for TP were endodontic failure ( n = 5), root fracture ( n = 1), and 1 extraction for other reasons. Cumulative survival probability was 58.7% for GFP and 74.2% for TP. Conclusions When using self-adhesively luted prefabricated posts, resin composite core build-up, and 2-mm ferrule to reconstruct severely damaged endodontically treated teeth, tooth survival is not influenced by post rigidity. Survival decreased rapidly after 8 years of observation in both groups.