An odontometric study of tooth dimension in diastematic dentition

BACKGROUND: One of the causes of the maxillary midline diastema (MMD) may be discrepancy between teeth and maxilla dimension. That can relate to two situations: when teeth have correct size but maxilla is too large or maxilla bone is in the proper size but teeth have reduced dimensions (microdontia). The present study has been conducted to investigate the differences in the linear dimensions of upper central and lateral incisors and canines in diastematic dentition and to compare them with the control group without diastema. MATERIALS AND METHODS: The study was conducted on Caucasian individuals (n = 102) divided into two groups: study group with MMD (n = 50) and control group without MMD (n = 52). The following measurements were done by digital calliper on their plaster models: 1. Width in the widest mesiodistal portion for upper right and left central incisors, lateral incisors and canines. 2. Length in the longest apico-coronal portion for the same teeth. RESULTS: Statistical analysis showed that comparisons of widths of left canines were significant. In the study group widths of left canines were lower than in the control group. Statistically significant differences in the length were observed for central incisors and canines in both sides. All measurements were lower in the diastema group of patients. CONCLUSIONS: Patients with diastema were characterised by incorrect tooth dimensions. The central incisors and upper canines were shorter in this group. Aesthetic closing of the diastema requires not only widening the crowns of the front teeth but also their elongation.