Morphological differences between the first and second maxillary premolar crowns: A three-dimensional surface homologous modeling analysis.

Autor: Miyazaki J; Department of Orthodontics, School of Dentistry at Matsudo, Nihon University, Chiba, Japan., Kondo S; Research Institute of Oral Science, School of Dentistry at Matsudo, Nihon University, Chiba, Japan. Electronic address: kondou.shintarou@nihon-u.ac.jp., Tanijiri T; Medic Engineering Corporation, Kyoto, Japan., Negishi S; Department of Orthodontics, School of Dentistry at Matsudo, Nihon University, Chiba, Japan.
Jazyk: angličtina
Zdroj: Journal of oral biosciences [J Oral Biosci] 2024 Mar; Vol. 66 (1), pp. 20-25. Date of Electronic Publication: 2024 Jan 25.
DOI: 10.1016/j.job.2024.01.010
Abstrakt: Objectives: The current study used a three-dimensional (3D) surface homologous modeling to analyze the structure of maxillary first premolar (P 1 ) and second premolar (P 2 ) crowns, to identify any morphological differences between them, particularly in their cuspal structures.
Methods: The study sample comprised 27 male elementary and junior high school students from Chiba Prefecture, Japan. Plaster casts were collected and the 3D coordinates were used to measure the crown structures. Thereafter, principal component (PC) analysis was carried out using the 3D coordinates of the homologous models, containing 4498 anatomical data points, including 9 landmarks.
Results: The findings indicated that P 1 was significantly larger than P 2 , despite both teeth exhibiting similar intercuspal distances. The homologous model analysis revealed that 61.5 % of the total variance could be explained up to the fourth PC. Overall size and shape in the mesiodistal and buccolingual directions were estimated using PC1 and PC2, respectively. Both components highlighted a shape factor, indicating that the buccal cusp was more well-developed than the lingual cusp in P 1 compared to P 2 .
Conclusions: The variations in the size of the mesial and distal premolar teeth and the relationships between the cusps in the completed tooth crowns can be explained using molecular biology developmental models.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier B.V.)
Databáze: MEDLINE
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