Assessing the prevalence of S-shaped root canal and associated genes in humans

• Published in: Annals of anatomy Vol. 244; p. 151977
• Main Authors: Küchler, Erika Calvano, Stroparo, Jeferson Luis de Oliveira, Matsumoto, Mirian Nakane, Scariot, Rafaela, Perin, Camila Paiva, Roskamp, Liliane, Menezes-Oliveira, Maria Angélica Hueb de, Proff, Peter, Kirschneck, Christian, Baratto-Filho, Flares
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 01-10-2022
• Subjects: Gene; Polymorphism; Root canal; Tooth; Tooth; Gene; Root canal; Polymorphism
• ISSN: 0940-9602; 1618-0402
• DOI: 10.1016/j.aanat.2022.151977

Multiple signaling molecules have been shown to play crucial roles in dental root development. Therefore, we aimed to investigate the prevalence of S-shaped roots and also to investigate, if single nucleotide polymorphisms (SNPs) in BMP2, BMP4 and SMAD6 are associated with this phenotype in humans.
This is a cross-sectional phenotype-genotype association study that used radiographs to determine the phenotypes and DNA to investigate SNPs in candidate genes. During the radiographic exam, teeth presenting root canal(s) doubly curved were considered S-shaped roots. SNPs in BMP2 (rs1005464 and rs235768), BMP4 (rs17563) and SMAD6 (rs2119261 and rs3934908) were blindly genotyped by real-time PCR using TaqMan assay. The relative and absolute frequency of S-shaped roots were calculated. Chi-square test was used to compare the genotype distributions between control and S-shaped groups.
Among the 578 subjects, 61 (10.6 %) presented at least one tooth with an S-shaped root. The most commonly affected type of tooth was the premolar. rs1005464 in BMP2 was statistically associated with an S-shaped root (p = 0.036). rs235768 in BMP2 was associated with an S-shaped root also in mandibular teeth (p = 0.017). A statistical significance was observed for the rs3934908 in SMAD6 (p = 0.049) for S-shaped root in the mandible. In the analysis stratified according to the type of tooth, rs235768 in BMP2 was associated with S-shaped roots in premolars (p = 0.029).
The prevalence of S-shaped roots is 10.6 % in permanent teeth. SNPs in BMP2 and SMAD6 could be involved in a higher chance to present S-shaped roots.