Variations in human DEJ scallop size with tooth type

• Published in: Journal of dentistry Vol. 38; no. 7; pp. 597 - 601
• Main Authors: Brauer, Delia S., Marshall, Grayson W., Marshall, Sally J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.07.2010; Elsevier; Elsevier Limited
• Subjects: Bicuspid - ultrastructure; Biological and medical sciences; Biomimetic model; Collagen; Confidence intervals; Cuspid - ultrastructure; Dental Enamel - ultrastructure; Dentin - ultrastructure; Dentino-enamel junction; Dentistry; Enamel; Fundamental and applied biological sciences. Psychology; Humans; Hypotheses; Incisor - ultrastructure; Interface; Mechanical properties; Microscopy, Electron, Scanning; Molar - ultrastructure; Molar, Third - ultrastructure; Mouth. Exocrine and endocrine salivary glands. Teeth. Esophagus; Odontometry; Scanning electron microscopy; Standard deviation; Studies; Teeth; Tooth - ultrastructure; Tooth Cervix - ultrastructure; Tooth structure; Vertebrates: digestive system; Tooth structure; Biomimetic model; Scanning electron microscopy; Interface; Dentino-enamel junction; Teeth; Dentin; Human; Anatomical variation; Molar tooth; Premolar; Dentistry; Incisor; Cuspid; Tooth enamel; Morphology; Junction; Tooth; Comparative study
• ISSN: 0300-5712; 1879-176X; 1879-176X
• DOI: 10.1016/j.jdent.2010.03.010

Recent literature suggests that the scalloped structure of the dentino-enamel junction (DEJ) is critical for DEJ stability. Aim of our study was to see if there are differences in scallop size and shape with tooth type. Enamel of extracted permanent human teeth was demineralised using EDTA. After fixation and dehydration the scallops of the DEJ were investigated in a scanning electron microscope. Scallop area and shape (circularity) were measured for molars, premolars, canines and incisors. Scallop area showed main effects for tooth type and specimen, while, due to high variability in third molars, there was also an interaction effect (repeated measures two-way ANOVA, p < 0.05). Differences between tooth types were statistically significant, suggesting that posterior teeth showed larger scallops compared to anterior teeth. Differences in shape (circularity) were not statistically significant. Our results suggest that teeth which are subject to higher masticatory loads (posterior teeth) show larger and more pronounced scallops. These findings might be of interest for improving other interfaces joining dissimilar materials.