External and internal ultramicroscopic characteristics of the tooth root apex in dogs were determined. Thirty teeth (16 maxillary fourth premolars, 7 mandibular first molars, and 7 maxillary canines) were examined. Teeth were obtained from 9 dogs with a total of 59 roots evaluated. Roots were sectioned perpendicular to the long axis (41), 3 to 7-mm from the apex, and others were sectioned longitudinally (18). Specimens were observed using scanning electron microscopy. The major diameter of 1,700 foramina and the depth of apical deltas were measured. The shape of the apex varied from round to elliptical and round-elliptical, with a regular or irregular surface. All root apices had many foramina, most (85.44 %) with a diameter < 50-μm. The maximum foramen diameter was 234.19-μm. Great variation was observed in the size of the apical foramina. The internal aspect of the cementum at the apical level showed a “sieved plug”. The extension of the cementum within the root canal forming the apical delta measured 2 ± 0.4-mm.
In human teeth, the cementoenamel junction (CEJ) can have different morphologies, known as Choquet cases or types: in type 1, the cementum overlaps the enamel; in type 2, the enamel overlaps the cementum; in type 3, the relationship between the cementum and enamel is edge-to-edge; and in type 4, there is a gap between the enamel and the cementum, with exposed dentin. Since little is known on the morphology of the CEJ in animals, the aim of this study was to characterize the structure of the CEJ of dog teeth by SEM. We studied 82 permanent teeth extracted from 4 dogs of similar size, aged from 7 months to 2 years. Teeth were grouped according to their size, sectioned and prepared for SEM. The teeth evaluated showed the 4 CEJ types. Type 3 was the most prevalent, being present, either alone or in combination, in 90.79% of the samples, followed by type 4 (present in 31.58% of the samples). Of the samples, 65.13% showed only one type, while 34.87% presented a combination of them. Types 3 and 4 were the only ones present alone (in 55.92% and 9.21% of the samples respectively), whereas the combinations between types 3 and 4 (20.40%) and types 1 and 3 (9.87%) were the most frequent. In all combinations, type 3 was predominant. The CEJ of the dogs evaluated showed a high degree of variability in the different types of teeth, within a same tooth, within the dentition of a single individual, and among individuals.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.