Search

The dental elements present similar and specific anatomical features, depending on the functions they have in the oral cavity. The permanent molars are the most complex structures, mainly the occlusal face, due to their function of food grinding. The aim of the present article is to present the upper first and second molars morphology, emphasizing the similarities and differences between them. Besides, the upper first and second molars of the collection of the Department of Morphology of Universidade Estadual de Paulista (UNESP), School of Dentistry, Araraquara, were evaluated regarding the presence of the oblique ridge, frequency and classification of the molar tubercle, and the crown morphology (upper second molars). In the 372 evaluated upper first molars, the molar tubercle was absent in most of the teeth. When present, the molar tubercle belonged to the mesiolingual cusp; 8.9% were classified as type I; 9.1% as type II; and 9.4% as type III. The oblique ridge was present in all upper first molars. The morphology of 401 upper second molars was also evaluated; 64.83% were tetracuspid; 35.16% tricuspid; and 17.02% presented compression morphology. In 100 tricuspid teeth, 50% presented oblique ridge, with it being prominent in 30%. No upper second molars presented molar tubercle. Although there are similarities between the upper first and second molars, we must always be aware of the features that differ between them, so their functionality can be restored.

Tooth whitening can be considered as one of the simplest, quickest and minimally invasive treatments for the aesthetic improvement of darkened teeth, in addition to presenting a low cost when compared to other restorative aesthetic alternatives...

Made available in DSpace on 2021-06-25T11:06:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Objectives The aim of this study was to evaluate the frequency of foramen cecum and dens in dente, and to verify the association of these structures in the maxillary lateral incisor (MLI). Materials and Methods The presence of foramen cecum in the lingual surface of 110 MLI was verified, and the teeth were radiographed to observe the presence of dens in dente, being classified according to the literature. An association study between the presence of foramen cecum and dens in dente was performed using the Cramer's V and chi-square statistical tests. Results The association was statistically significant between the foramen cecum and the dens in dente. Concomitant presence was observed in 17.27%, being a high rate when compared with the presence of foramen cecum alone (9.09%) or dens in dente alone (8.18%). In addition, type I (minimal invagination, confined to the crown of the tooth and not extending beyond the level of the cementum-enamel junction) was the most frequent (82.14%). Conclusions We emphasize the importance of alerting the dentist to the presence of a foramen cecum on the lingual surface of the MLI, as it is likely that dens in dente is usually of type I. Thus, the foramen cecum is a sign that can assist the dental surgeon in the discovery of dens in dente and clinical conduct to be taken. Department of Morphology Genetics Orthodontic and Pediatric Dentistry School of Dentistry São Paulo State University (UNESP), Rua Humaitá, 1680 Department of Diagnosis and Surgery School of Dentistry São Paulo State University Department of Morphology Genetics Orthodontic and Pediatric Dentistry School of Dentistry São Paulo State University (UNESP), Rua Humaitá, 1680 Department of Diagnosis and Surgery School of Dentistry São Paulo State University

The aim of this study were characterize acellular collagen matrices derived from porcine pericardium (PP) and to evaluate their properties after sterilization by ethylene oxide and gamma ray. PP matrices were subjected to alkaline hydrolysis (AH), and samples were characterized for biological stability, membrane thickness measurements, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Subsequently, the matrices were frozen, lyophilized and sterilized by ethylene oxide or gamma radiation. For in vitro assays, CHO-K1 cell culture was used and evaluated for cytotoxicity, clonogenic survival assay, genotoxicity and mutagenicity. Analysis of variance (ANOVA) was used, followed by Dunnett’s post-test, with a significance level of 5%. After AH, there was no significant change in matrix thickness. The relative biodegradability of the material after implantation was observed. Morphology and dimensions had small changes after AH. As for cell viability, none of the tested matrices showed a statistically significant difference (p &gt, 0.05, Dunnett) regardless of the sterilization method. Furthermore, it was found that PP matrices did not interfere with the proliferation capacity of CHO-K1 cells (p &gt, Dunnett). As for genotoxicity, when sterilized with ethylene oxide (NP, P12 and P24), it showed genotoxic potential, but it was not genotoxic when sterilized by gamma radiation. No mutagenic effects were observed in either group. PP-derived collagen matrices hydrolyzed at different times were not cytotoxic. It is concluded that the best method of sterilization is through gamma radiation, since no significant changes were observed in the properties of the PP matrices.