In-depth morphological evaluation of tooth anatomic lengths with root canal configurations using cone beam computed tomography in North American population

Abstract Objective This study aimed to assess the association between tooth size and root canal morphology by using CBCT analysis. Methodology In this retrospective study, tooth anatomic lengths (crown and root lengths, buccolingual and mesiodistal dimensions) of 384 patients were assessed and correlated with Vertucci's root canal morphology classification. Data was analyzed for gender-related differences using the independent sample t-test, ANOVA, and the Pearson's correlation for a possible relation between anatomic lengths and canal morphology. Results The maxillary first and second premolars showed a greater predilection for Type IV and II variants, respectively, while the mandibular first premolar showed a greater predilection for Type II canal system. The root canal system of the mandibular second premolar showed maximal diversity (47% Type I, 30% Type II, and 20% Type III). The dimensions were greater in men regardless of tooth type. The most significant relation (p<0.05) between the anatomic size and canal morphology was observed in the maxillary first premolars, followed by the mandibular canines (buccolingual dimension) and the lower second premolars (crown length). Negative correlations existed between the crown length and the patient's age for the anterior teeth and mandibular second premolar (r=−0.2, p<0.01). Conclusions The most common canal formation for anterior teeth was the Type I. The anatomic lengths had the strongest influence on the canal configuration of the maxillary first premolar, with Type IV being the most common root canal system. The mandibular second premolars showed maximal diversity in the canal classification terms and had a significant correlation with their crown lengths. Clinical Relevance The complex relationship between the canal morphology and anatomic tooth sizes need meticulous awareness and recognition during endodontic procedures, in conjunction with the demographic variabilities.

Mesiodistal and buccolingual crown size of deciduous teeth from a tooth bank in Brazil / Dimensões mesiodistais e vestíbulo-linguais de coroas de dentes decíduos de um banco de dentes no Brasil

Objective: The size of primary teeth in the current Brazilian population has not been studied yet; the aim of this in vitro study was to document the size and variation of deciduous teeth from a tooth bank in São Paulo, Brazil. Methods: A sample of 1,095 deciduous teeth was obtained from a tooth bank at the Dental School of the University of Sao Paulo. The measurements were made with a digital caliper. Only unworn, undamaged teeth were measured. Results: At mesiodistal diameter, maxillary central incisor showed the highest variation and the mandibular first molar the least. In buccolingual sizes, mandibular second molar was the tooth with the highest variability. Conclusion: This study provides a record of primary tooth sizes in Brazilian children. There was an evident variation of size of the primary teeth.

Objetivo: O tamanho dos dentes decíduos na população brasileira atual ainda não foi estudado, o objetivo deste estudo in vitro foi documentar o tamanho e a variação de dentes decíduos de um banco de dentes, em São Paulo, Brasil. Métodos: Uma amostra de 1.095 dentes decíduos foi obtida a partir de um banco de dentes da Faculdade de Odontologia da Universidade de São Paulo. As medições foram feitas com um paquímetro digital. Apenas dentes não desgastados e não danificados foram medidos. Resultados: Em relação ao diâmetro mesiodistal, o incisivo central superior apresentou a maior variação e primeiro molar inferior a mínima. Em relação aos tamanhos vestíbulo-linguais, o segundo molar foi o dente com a maior variabilidade. Conclusão: Este estudo forneceu um registro de tamanhos dos dentes decíduos de crianças brasileiras. Houve uma variação evidente de tamanho dos dentes decíduos.