Correlation Theory of the Maxillary Central Incisor, Face and Dental Arch Shape in the Serbian Population.

Background and Objectives: According to the modified Williams theory, the shape of the maxillary central incisor corresponds to the shape of the maxillary alveolar ridge (dental arch) and the shape of the face. Moreover, the standards of beauty suggest that the center of the face of an individual with a full set of teeth should match the center of the maxillary and mandibular dental arches. The purpose of this study is to conduct a comparative cross-sectional study on the matching of the shape of the face, maxillary central incisor and maxillary dental arch as well as the matching of the midfacial line and dental arches in subjects with complete dentition. Materials and Methods: The study included 90 subjects of both sexes. The matching of the shape of the face and midfacial line, i.e., dental arches and maxillary incisors, was determined by analysing photographs, whereas the shape of the dental arch was determined by analysing plaster models. Results: No significant gender-related differences were found either in the shape of the maxillary central incisor that matched the shape of the maxillary dental arch (p = 0.349) or in the shape of the dental arch that matched the shape of the face (p = 0.697). However, a significant difference was noted in the shape of the teeth that matched the shape of the face (p = 0.043), which was more significantly impaired in men. In addition, the matching of the mid-face and the mid-dental arch was significantly greater in women (p = 0.016). Conclusions: The modified Williams theory was confirmed in most subjects, thus it can be considered a relevant guideline when determining the shape of teeth after their loss. The highest percentage of matching in both sexes was with the shape of the face and dental arch. There was no positive correlation between the middle of the maxillary and mandibular dental arch in most cases.

Development and psychometric properties of the Serbian version of the Orofacial Esthetic Scale.

OBJECTIVE: The aim of the study was to develop the Serbian language version of the Orofacial Esthetic Scale questionnaire (OES SERB) and to evaluate its psychometric properties. METHODS: The study included 226 subjects - 110 dental students and 116 patients (the validation sample). The students answered all the questions individually with the help of supervisors, whereas the prosthodontic patients were interviewed by the same trained dentist. The reliability and validity of the questionnaire were assessed. RESULTS: Internal consistency of the OES-SERB was considered satisfactory (Cronbach's alpha 0.92, inter-item correlation coefficient ranged between 0.735 and 0.898). The construct validity of the OES was proved using exploratory factor analysis, which confirmed the one- dimensional model of the OES-SERB that assumed 66.549% of the variance. The Bartlett's test of sphericity was 1380.134 (df = 28, p < 0.001) and the Kaiser-Meyer-Olkin (KMO) test was 0.900. The total score was statistically significantly different between students and patients (p < 0.001), which confirmed the discriminant validity. CONCLUSION: The Serbian version of the OES, adapted to the cultural setting of the Republic of Serbia, has exhibited excellent psychometric properties and has been confirmed as a one-dimensional tool for self-assessment of the appearance of the orofacial region. CLINICAL SIGNIFICANCE: The Serbian version of the OES has good psychometric properties and is a valuable instrument for self-assessment of the appearance of the orofacial region.

Polymethyl methacrylate resin for provisional restoration affects rat macrophage function in in vitro conditions.

PURPOSE: This study evaluated the cytotoxic effects of polymethyl methacrylate resin extracts on rat macrophage viability in in vitro conditions. METHODS: Prepared test specimens were immersed in 5 mL of artificial saliva and incubated for 24, 48, and 72 h at 37°C. The cytotoxicity of the obtained solutions of extracted resins, used as a stock solution (100%) and diluted with Roswell Park Memorial Institute (RPMI) medium to obtain the working solutions (50, 40, 30, 20, 10, and 5%), was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS: No dose-dependent toxic activity in macrophage culture was detected for the three types of extracts obtained after 24, 48, and 72 h of material extraction. The shortest extraction of material was found to be completely non-toxic, and the 20% concentration of this extract obtained caused a significant increase in cell ability to metabolize MTT. Extracts obtained after 72 h of extraction showed the highest cytotoxic potential of 50%, 40% and 30%, and extracts obtained after 48 and 72 h of extraction at concentrations of 5% and 10% had a proliferative effect on the macrophage cell line. CONCLUSION: This study demonstrated that the highest cytotoxic effect was observed in cells exposed to the highest concentrations (50, 40, and 30%) of the extracts that were extracted for 72 h.