Permanent human canines: their importance for dental anatomy teaching

Objectives: Permanent canines have an important functional role during mastication due to their anatomy,cbesides its relevance in oral esthetics. However, dentistry undergraduates have great difficulty in differentiating them during dental anatomy classes. The objective of this work was to study the morphology of the extracted permanent maxillary canines (MC) and lower canine (LC) in order to describe the anatomical similarities and differences.Methods: One hundred maxillary canines and 100 lower canines were evaluated. Measurements were performed using a digital caliper, and also visual analysis. The data obtained in each evaluation were submitted to descriptive statistical analysis, and the chi-square test and Fisher's exact test with a significance level of 5% were applied.Results: It was observed that the MC root groove was present on the two proximal surfaces and the groove depth was greater on the mesial surface, as reported in the literature. The MC incisal ridge was normally worn, and imprecision in dental differentiation could occur during the anatomical study, while it is stated that the incisal ridge allows distinguishing this tooth by a simple visual examination. The marginal ridges of the MC had a moderate prominence, as observed in the literature. The MC cingulum often presented a moderate prominence, contradicting some studies which reported a large cingulum. The presence of the cervicoincisal ridge on the lingual surface was frequently observed with moderate, absent or little prominence, while some authors reported that this structure is quite evident. Furthermore, it is reported that MC usually presents aforamen cecum, which was not observed in our sample. LC often presented a worn incisal ridge. The cingulum, marginal ridges, lingual fossa and developmental grooves were less evident and, in some cases, the lingual surface presented a flat shape, which is not usually reported in the literature.Conclusions: The morphological differences and similarities of MC and LC are important for a detailed anatomical study to help dentistry undergraduates identify them correctly. Furthermore, the anatomical study is important for the restorative area for an appropriate aesthetics and function rehabilitation.Objectives: Permanent canines have an important functional role during mastication due to their anatomy,cbesides its relevance in oral esthetics. However, dentistry undergraduates have great difficulty in differentiating them during dental anatomy classes. The objective of this work was to study the morphology of the extracted permanent maxillary canines (MC) and lower canine (LC) in order to describe the anatomical similarities and differences.Methods: One hundred maxillary canines and 100 lower canines were evaluated. Measurements were performed using a digital caliper, and also visual analysis. The data obtained in each evaluation were submitted to descriptive statistical analysis, and the chi-square test and Fisher's exact test with a significance level of 5% were applied.Results: It was observed that the MC root groove was present on the two proximal surfaces and the groove depth was greater on the mesial surface, as reported in the literature. The MC incisal ridge was normally worn, and imprecision in dental differentiation could occur during the anatomical study, while it is stated that the incisal ridge allows distinguishing this tooth by a simple visual examination. The marginal ridges of the MC had a moderate prominence, as observed in the literature. The MC cingulum often presented a moderate prominence, contradicting some studies which reported a large cingulum. The presence of the cervicoincisal ridge on the lingual surface was frequently observed with moderate, absent or little prominence, while some authors reported that this structure is quite evident. Furthermore, it is reported that MC usually presents aforamen cecum, which was not observed in our sample. LC often presented a worn incisal ridge. The cingulum, marginal ridges, lingual fossa and developmental grooves were less evident and, in some cases, the lingual surface presented a flat shape, which is not usually reported in the literature.Conclusions: The morphological differences and similarities of MC and LC are important for a detailed anatomical study to help dentistry undergraduates identify them correctly. Furthermore, the anatomical study is important for the restorative area for an appropriate aesthetics and function rehabilitation

BONEFILL® block as alternative for bone substitute: a toxicological evaluation

Bone substitutes based on hydroxyapatite (HA) and Bonefill® (BO - inorganic bovine bone) associated with poly(lactic-co-glycolic acid) (PLGA) (HA/PLGA and BO/PLGA) were evaluated concerning cytotoxicity, genotoxicity and mutagenicity as potential candidates for bone repair. The materials were developed and provided by Bionnovation Biomedical Products Ltda. Eluates from these bone substitutes were prepared for toxicity evaluations using eukaryotic cell cultures. HA/PLGA was used as a comparison for Bonefill®. Cell viability was evaluated by XTT assay and surviving fraction was calculated for clonogenic survival. Additionally, tail moment was used to assess genotoxicity (comet assay). The frequencies of binucleated cells with micronucleus (FBMN), micronucleus (FMN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) were analysed by cytokinesis-block micronucleus assay (CBMN assay). Results showed no statistical difference in cell viability compared with negative control (NC) The eluates did not promote delayed cytotoxicity whereas the surviving fraction rate for cultured cells was similar to NC. Furthermore, no genotoxicity or mutagenicity effects were observed for cultured cells with the Bonefill/PLGA and HA/PLGA eluates. In conclusion, the negative cytotoxicity, genotoxicity and mutagenicity results indicate that these bone substitutes presented interesting preliminary results as potential biomaterials for bone repair

BONEFILL® block as alternative for bone substitute: a toxicological evaluation

Bone substitutes based on hydroxyapatite (HA) and Bonefill® (BO - inorganic bovine bone) associated with poly(lactic-co-glycolic acid) (PLGA) (HA/PLGA and BO/PLGA) were evaluated concerning cytotoxicity, genotoxicity and mutagenicity as potential candidates for bone repair. The materials were developed and provided by Bionnovation Biomedical Products Ltda. Eluates from these bone substitutes were prepared for toxicity evaluations using eukaryotic cell cultures. HA/PLGA was used as a comparison for Bonefill®. Cell viability was evaluated by XTT assay and surviving fraction was calculated for clonogenic survival. Additionally, tail moment was used to assess genotoxicity (comet assay). The frequencies of binucleated cells with micronucleus (FBMN), micronucleus (FMN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) were analysed by cytokinesis-block micronucleus assay (CBMN assay). Results showed no statistical difference in cell viability compared with negative control (NC) The eluates did not promote delayed cytotoxicity whereas the surviving fraction rate for cultured cells was similar to NC. Furthermore, no genotoxicity or mutagenicity effects were observed for cultured cells with the Bonefill/PLGA and HA/PLGA eluates. In conclusion, the negative cytotoxicity, genotoxicity and mutagenicity results indicate that these bone substitutes presented interesting preliminary results as potential biomaterials for bone repair

Identification of Lower Central Incisors

Unlike the other teeth, the permanent lower central incisors have great symmetry between the proximal surfaces, being difficult to distinguish them. It was intended to facilitate the study of the anatomy of the lower central incisor for dentistry students, that this study searched for a better way to differentiate the third quadrant element (31) from the fourth quadrant element (41). The purpose of this chapter was to evaluate 100 permanent lower central incisors of the didactic collection of the Discipline of Anatomy of the Department of Morphology of the School of Dentistry of Araraquara - UNESP and to verify the presence of correlation between the some anatomical features. Besides, it was evaluated if there was difference between 31 and 41. It was verified that the systematic methodology used for the evaluation of the incisors in this study facilitated the identification of the teeth. There was no statistically significant difference between the measurements of 31 and 41. Distinguishing the right from the left central incisor is difficult, even for experienced practitioners. We could observe that the measurements do not facilitate the identification of teeth of different quadrants. Therefore, the anatomical features are relevant for the study of the dental anatomy in the identification of the lower central incisors

Evaluation of the Anatomy of the Lower First Premolar

This chapter provides information about the lower first premolars. This tooth is considered to be one of the most complex teeth and the dentistry graduation students usually have difficulties in identifying it. The aim of this chapter is to present a detailed morphological study of extracted lower first premolars. One hundred lower first premolars, belonging to the collection of the Laboratory of Anatomy of the Department of Morphology of the São Paulo State University (UNESP), School of Dentistry, Araraquara, SP, Brazil, were evaluated. Nine measurements were performed through direct observation without any instruments. Other 20 measurements were made by photographs and they were analyzed by the Image Tool 3.0 program. According to the results, it was concluded that most of the teeth presented the following features such as one lingual cusp; the distal occlusal pits were wider than the mesial occlusal pits; an enamel bridge linking the buccal and lingual cusps; the grooves in the lingual surface that emerged from the mesial and distal occlusal pits were absent, and where the grooves were present, they emerged from the mesial occlusal pit; one rectilinear root with no root grooves and where the root groove was present, it was observed in the mesial surface

Susceptibility Polymorphism in the Promoter Region of IL-4 and IL-13 in Individuals with Periodontitis: A Systematic Review

Objective: To understand the susceptibility to single nucleotide polymorphisms in the promoter region of Interleukin-4 (IL-4) and Interleukin-13 (IL-13) in patients with and without periodontal disease. Thus, a systematic review of available studies on the subject was performed. Material and Methods: A protocol was conducted for registration in the International Prospective Register of Systematic Reviews (PROSPERO) under CRD42021246646. For this search, studies were selected from the Scopus, Web of Science, Virtual Health Library, Embase, Cochrane Library, and PubMed databases. The selection criteria consisted of case-control and cohort studies published in English that had data on IL-4 and IL-13 genetic polymorphisms in patients with and without periodontal disease in the same study. The obtained studies were managed by EndNote Program™ X7 version and the Rayyan Platform. Regarding the risk of bias, we used the Newcastle-Ottawa Scale, which classified the studies using high-quality methodology. Results: After the selection process, three studies presented the eligibility criteria. No relation between IL-13 and susceptibility to periodontal disease was found. IL-4 gene (IL-4 -590C/T; IL-4-34C/T; rs2243248) was associated with susceptibility to the development of periodontitis. Conclusion: An association between IL-4 and the susceptibility of periodontitis was verified. Further case-control studies are needed to create more concrete conclusions on the subject