A novel lncRNA-mediated epigenetic regulatory mechanism in periodontitis.

Periodontitis is a highly prevalent chronic inflammatory disease with an exaggerated host immune response, resulting in periodontal tissue destruction and potential tooth loss. The long non-coding RNA, LncR-ANRIL, located on human chromosome 9p21, is recognized as a genetic risk factor for various conditions, including atherosclerosis, periodontitis, diabetes, and cancer. LncR-APDC is an ortholog of ANRIL located on mouse genome chr4. This study aims to comprehend the regulatory role of lncR-APDC in periodontitis progression. Our experimental findings, obtained from lncR-APDC gene knockout (KO) mice with induced experimental periodontitis (EP), revealed exacerbated bone loss and disrupted pro-inflammatory cytokine regulation. Downregulation of osteogenic differentiation occurred in bone marrow stem cells harvested from lncR-APDC-KO mice. Furthermore, single-cell RNA sequencing of periodontitis gingival tissue revealed alterations in the proportion and function of immune cells, including T and B cells, macrophages, and neutrophils, due to lncR-APDC silencing. Our findings also unveiled a previously unidentified epithelial cell subset that is distinctively presenting in the lncR-APDC-KO group. This epithelial subset, characterized by the positive expression of Krt8 and Krt18, engages in interactions with immune cells through a variety of ligand-receptor pairs. The expression of Tff2, now recognized for its role in chronic inflammatory conditions, exhibited a notable increase across various tissue and cell types in lncR-APDC deficient mice. Additionally, our investigation revealed the potential for a direct binding interaction between lncR-APDC and Tff2. Intra-gingival administration of AAV9-lncR-APDC was shown to have therapeutic effects in the EP model. In conclusion, our results suggest that lncR-APDC plays a critical role in the progression of periodontal disease and holds therapeutic potential for periodontitis. Furthermore, the presence of the distinctive epithelial subpopulation and significantly elevated Tff2 levels in the lncR-APDC-silenced EP model offer new perspectives on the epigenetic regulation of periodontitis pathogenesis.

Soft-Tissue Changes After Using Collagen Matrix Seal or Collagen Sponge With Allograft in Ridge Preservation: A Randomized Controlled Volumetric Study.

The objective of this study is to assess alterations in buccal soft-tissue contour after alveolar ridge preservation (ARP) using either a collagen matrix seal (CMS) or a collagen sponge (CS) as barriers with freeze-dried bone allograft (FDBA). Participants (28 total) were randomly assigned to the CMS group or CS group (14 participants each). The same clinical steps were used in both barriers. Cast models were taken at baseline and 4 months, and both models were then optically scanned and digitally superimposed. Volumetric, surface, and distance-adjusted measurements were calculated to assess buccal soft-tissue alterations. Surface area and volume loss in the CMS group were observed to be 71.44 ± 1189.09 mm2 and 239.58 ± 231.89 mm3, respectively. The CS group showed measurements of 139.56 ± 557.92 mm2 and 337.23 ± 310.18 mm3. Mean buccal soft-tissue loss and minimum-maximum distance loss were less in the CMS group (0.88 ± 0.52 mm and 0.2-2.15 mm, respectively) as compared with the CS group (1.63 ± 1.03 mm and 0.3-3.68 mm, respectively), with no statistically significant difference between the groups (P = .2742). Both alveolar ridge preservation barriers were unable to entirely prevent soft-tissue contour changes after extraction. However, collagen matrix seal application was slightly better in minimizing the amount of soft-tissue reduction compared with the CS.

Development and Implementation of a Clinical Dental Faculty Evaluation Instrument.

The aim of this study was to develop and test the reliability of an instrument to evaluate the quality of clinical teaching among dental school faculty. Fourth-year dental students' perspectives on effective clinical teaching were first collected in focus group meetings. An 11-item questionnaire to assess seven domains of clinical teaching was developed based on the collected student perspectives and a medical model. All 374 third- and fourth-year dental students at one U.S. dental school in 2015 were invited to evaluate four clinical instructors whom they felt were strong role models and four clinical instructors whom they felt would benefit from constructive criticism. The survey was completed by 139 students (37.2% response rate); they evaluated 96 dental instructors. The results showed that the survey demonstrated strong internal reliability, with Cronbach's alpha values of >0.95 for each of the seven domains. In addition, there was significant agreement between groups: the interclass correlation (ICC) ranged from 0.97 to 0.99. These results suggest that the clinical faculty evaluation instrument developed in this study is a reliable method that can be used to evaluate dental faculty members. This system can be a valuable guide for clinical faculty members and administrators in assessing and improving clinical teaching effectiveness.

Faculty Development Initiatives in Academic Dentistry: A Systematic Review.

The aims of this systematic review were to collect a list of published articles on dental faculty development and to determine the types and location of programs evaluated and years of publication. A subset of selected articles were then assessed using Kirkpatrick assessment model four levels: learner reaction, participant learning, participant behavioral change, and changes in organizational practice. The search, conducted in 2016, comprised all potentially relevant articles in the following databases: PubMed, EMBASE via Ovid, and ERIC. The study screening was done by three reviewers in multiple stages: by title, abstract, and full text review. Following deduplication, 257 titles were obtained; of those, 102 articles were selected for abstract review. As a result of that review, 32 articles were excluded, leaving 70 for data extraction. The majority of the 70 articles were about programs in the U.S., and two-thirds were studies conducted at individual academic institutions. Most focused on faculty development initiatives (n=49), followed by retention (n=22), recruitment (n=16), and/or promotion/tenure (n=11). The year with the highest number of published articles was 1991 (n=10, 14%), followed by 2007 and 2011 (n=6, 8.6% each). Among the 12 articles evaluated with the Kirkpatrick model, most assessed Levels 1, 2, and 3, but very few addressed Level 4. Research in those 12 articles was conducted primarily at two dental schools: New York University College of Dentistry (n=5) and University of Florida College of Dentistry (n=4). This study generated a varied list of published articles on faculty development, but the results point to the need for research at more institutions and using additional methodologies.

Efficacy of collagen matrix seal and collagen sponge on ridge preservation in combination with bone allograft: A randomized controlled clinical trial.

AIM: To test whether the use of collagen matrix seal (CMS) results in similar hard and soft tissue remodelling to that with collagen sponge (CS) used as barriers 4 months following alveolar ridge preservation (ARP), in combination with freeze-dried bone allograft (FDBA). MATERIALS AND METHODS: Twenty-eight patients were randomly assigned to the two groups. Clinical and radiographic measurements were recorded with the same stent at baseline and 4 months for standardization. The flapless technique following a traumatic extraction was used for the two types of barriers. RESULTS: All patients completed the study, 14 in the CMS group and 14 in the CS group. Reduction in coronal ridge width (1.21 mm-14.91% CMS and 1.47 mm-20.40% CS) and vertical buccal bone resorption (0.30 mm CMS and 0.79 mm CS) were not significantly different. A slight increase in buccal gingival thickness at the coronal part was observed in both groups (0.9 mm CMS and 0.5 mm CS). CONCLUSIONS: Collagen matrix seal and CS, when combined with FDBA, significantly minimized ridge resorption in all dimensions and maintained buccal soft tissue thickness in sockets with a buccal plate loss of <2 mm in comparison to previously reported findings recorded after tooth extraction without ARP.

Guided Tissue Regeneration Involving Piercing-Induced Lingual Recession: A Case Report.

Recession on the lingual aspect of mandibular incisors may occur in patients with history of tongue piercing and other factitious traumatic habits. Treatment of these areas is challenging due to the site-specific anatomical features of the region. This case report presents a novel approach for a specific type of mandibular lingual defect caused by tongue piercing. A nonresorbable titanium-reinforced barrier membrane combined with an allograft and enamel matrix derivatives was used to promote regeneration of periodontal attachment. Reentry surgery for membrane removal was performed at 8 weeks. The time from initial surgery to final follow-up was 18 months.