Objective: To evaluate the hydrothermal aging effect on the translucency of partially stabilized tetragonal zirconia with yttria (Y-TZP) used as monolithic or fully milled zirconia and of core type. Methods: Twenty disc-shaped specimens (1 and 10 mm) for each type of monolithic and core Y-TZP materials were milled and sintered according to the manufacturer’s instruction. The final specimens were divided into two groups according to the type of Y-TZP used. Translucency parameter (TP) was measured over white and black backgrounds with the diffuse reflectance method; X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to analyze the microstructure of both Y-TZP types before and after aging. Data for TP values was statistically analyzed using Student’s t-test. Results: Monolithic Y-TZP showed the highest TP mean value (16.4 ± 0.316) before aging while core Y-TZP showed the lowest TP mean value (7.05 ± 0.261) after aging. There was a significant difference between the two Y-TZP types before and after hydrothermal aging. XRD analysis showed increases in monoclinic content in both Y-TZP surfaces after aging. Conclusion: Monolithic Y-TZP has a higher chance to low-temperature degradation than core type, which may significantly affect the esthetic appearance and translucency hence durability of translucent Y-TZP.

Background: Dentin is a permeable tubular composite and complex structure, and in weight, it is composed of 20% organic matrix, 10% water, and 70% hydroxyapatite crystalline matrix. Demineralization of dentin with gradient concentrations of ethylene diamine tetraacetic acid, 0.6 N hydrochloric acid, or 2% nitric acid removes a major part of the crystalline apatite and maintains a majority of collagen type I and non-collagenous proteins, which creates an osteoinductive scaffold containing numerous matrix elements and growth factors. Therefore, demineralized dentin should be considered as an excellent naturally-derived bioactive material to enhance dental and alveolar bone tissues regeneration. Method: The PubMed and Midline databases were searched in October 2021 for the relevant articles on treated dentin matrix (TDM)/demineralized dentin matrix (DDM) and their potential roles in tissue regeneration. Results: Several studies with different study designs evaluating the effect of TDM/DDM on dental and bone tissues regeneration were found. TDM/DDM was obtained from human or animal sources and processed in different forms (particles, liquid extract, hydrogel, and paste) and different shapes (sheets, slices, disc-shaped, root-shaped, and barrier membranes), with variable sizes measured in micrometers or millimeters, demineralized with different protocols regarding the concentration of demineralizing agents and exposure time, and then sterilized and preserved with different techniques. In the act of biomimetic acellular material, TDM/DDM was used for the regeneration of the dentin-pulp complex through direct pulp capping technique, and it was found to possess the ability to activate the odontogenic differentiation of stem cells resident in the pulp tissues and induce reparative dentin formation. TDM/DDM was also considered for alveolar ridge and maxillary sinus floor augmentations, socket preservation, furcation perforation repair, guided bone, and bioroot regenerations as well as bone and cartilage healing. Conclusion: To our knowledge, there are no standard procedures to adopt a specific form for a specific purpose; therefore, future studies are required to come up with a well-characterized TDM/DDM for each specific application. Likely as decellularized dermal matrix and prospectively, if the TDM/DDM is supplied in proper consistency, forms, and in different sizes with good biological properties, it can be used efficiently instead of some widely-used regenerative biomaterials.

Objective Evaluate and compare the 5‐year clinical performance of three high‐viscosity glass ionomer restorative materials in small class II restorations. Materials and Methods Forty patients, each with four class II restorations, were enrolled in this trial. A total of 160 restorations were placed, 25% for each material, as follows: three high‐viscosity conventional glass ionomer restorative systems (Ketac Universal Aplicap, EQUIA Forte and Riva Self Cure HV) and a microhybrid resin composite system (Filtek Z250). Clinical evaluation was performed at baseline and after 1, 3, and 5 years by two independent examiners using FDI criteria. Epoxy resin replicas were observed under scanning electron microscope (SEM) to examine surface characteristics. Data were analyzed with Kruskal‐Wallis, Mann–Whitney U, Friedman, and Wilcoxon signed‐rank tests (p < 0.05). Results The success rates were 100% for resin composite, 97.4% for Ketac Universal, and 94.9% for both EQUIA Forte and Riva HV restorations. Statistically significant differences were observed between all groups in terms of surface luster and color match criteria (p < 0.05). Statistically significant changes were found over time for all criteria except for fracture of material, postoperative hypersensitivity, recurrence of caries, tooth integrity, periodontal response, adjacent mucosa, and oral health criteria (p > 0.05). SEM evaluations were in accordance with the clinical findings. Conclusions Although drawbacks in surface luster and color match appeared over the 5‐year evaluation period, the three high‐viscosity glass ionomer restorative materials provided successful clinical performance in small to medium sized class II cavities compared to microhybrid resin composite. Clinical Significance Glass ionomer restorations exhibited clinical performance similar to that of microhybrid resin composite restorations in small class II cavities subsequent to 5‐year evaluation.

SUMMARY Objective: This study evaluated the effect of preheating resin composites (RCs) on the clinical performance of class I restorations during a 36-month period using a split-mouth, double-blinded randomized design. Methods and Materials: A total of 35 patients were selected. Every patient received one pair of class I nanofilled resin composite (RC, Filtek Z350 XT) posterior restorations (n=70). One side of the mouth received preheated composites; on the other side, the composite was placed in a nonheated state following the manufacturer’s instructions. These restorations were evaluated at 1-week (baseline), 12-months, 24-months, and 36-months using the FDI World Dental Federation criteria. The statistical analyses were also performed using the Wilcoxon and Friedman tests with the level of significance set at 0.05. Results: After 36 months, 33 patients attended the recall visits, and 66 restorations were evaluated. The Friedman and Wilcoxon signed-rank tests revealed insignificant differences between both groups (p&gt;0.05) for all FDI parameters. However, a significant difference was detected for staining as a criterion at 36 months (p=0.01). Moreover, a significant difference in the staining was detected when the baseline and 36 months were compared in the nonheated RC group (p=0.001). For esthetic, functional, and biological properties, the nonheated composite exhibited 93.9%, 100%, and 100% of the clinically accepted scores, respectively, and the preheated group presented 100% for all properties. Four restorations had postoperative sensitivity at baseline for nonheated (11.4%) and five for preheated (14.2%), but the postoperative sensitivity scores were considered highly acceptable at 12-, 24-, and 36-months. Conclusions: After 36 months, preheated nanofilled RCs showed an acceptable clinical performance similar to that of the nonheated ones in class I restorations, but with better resistance to marginal staining.

Background:Biodentine is comparatively a new biomaterial claimed to have properties comparable to mineral trioxide aggregate (MTA). Biodentine and MTA are effectively used for direct pulp capping (DPC), and they are capable of regenerating relatively damaged pulp and formation of hard dentine bridge.Objectives:The aim of this systematic review was to test the null hypothesis of no difference between Biodentine and MTA as DPC materials for human permanent mature teeth, against the alternative hypothesis of a difference.Data Sources:Clinical trials were identified by electronic databases searches of Midline, CENTRAL Cochrane Library, Latin American and Caribbean Health Sciences Literature, Scopus, Scientific Electronic Library Online, evidence-based endodontics literature, KoreaMed, and Google Scholar. The literature search was performed from January 2010 to February 2018. Hand searches were also performed for relevant abstracts, books, and reference lists. Titles and abstracts of studies identified using the above-described protocol were independently screened by two authors. Full texts of studies judged by title and abstracts to be relevant were independently evaluated by two authors for stated eligibility criteria.Study Eligibility Criteria:The eligibility criteria included randomized clinical trials (RCTs) and non-RCTs.Participants:Patients with permanent mature molars indicated for surgical extraction or molars that have symptomless exposure of vital pulp tissue by caries or trauma. In both cases, the molars were subjected to DPC.Interventions:The pulp exposures were directly treated by Biodentine or MTA.Study Appraisal:To assess article quality, two authors independently used the risk of bias in nonrandomized studies – of interventions.Methods:Qualitative metasynthesis was used to analyze data across qualitative studies.Results:The initial search identified 8725 unique references through the search process. No additional studies were identified through handsearching. After filtering, 915 references were recorded and screened. After the eligibility criteria were applied, seven unduplicated prospective and retrospective cohort studies were included in the qualitative metasynthesis.Limitations:Further RCTs with much larger sample size and proper methodology with longer observational time are still in need to adequately address the questions of the present systematic review.Conclusion and Implications of Key Findings:Within the limitations of this review, it may be concluded that Biodentine had a similar effect on dentin bridge formation likely to MTA. However, this conclusion is based on only very few well-conducted prospective and retrospective cohort studies.Systematic Review Registration Number:The review had been registered with PROSPERO (registration number CRD42018089302).