Occlusal‐supporting ability of individual maxillary and mandibular teeth

Abstract

This study aimed to analyse occlusal force, area and pressure for individual maxillary and mandibular teeth by assessing their occlusal-supporting abilities. Ninety-nine subjects (49 men and 50 women; average age, 24·7 ± 3·4 years; range, 20-37 years) performed maximal voluntary clenching twice for 3 s in both the intercuspal position and the intercuspal position with sliding movement from edge-to-edge occlusion, with a pressure-sensitive sheet placed between the maxillary and mandibular dental arch. Occlusal force, area and pressure of individual teeth were calculated by colour development in the pressure-sensitive sheet with special analytical equipment and software. Occlusal contact condition of individual teeth was confirmed using the intra-occlusal record. All data were analysed using unpaired Student's t-test, Kruskal-Wallis test and Scheffe's test for multiple comparisons with a significance level of P < 0·05. The occlusal pressure in the intercuspal position with sliding movement from edge-to-edge occlusion was adopted as the representative occlusal-supporting ability for each individual tooth, although there were, in part, statistically significant differences in the effects of laterality, performance and gender. Overall, the occlusal pressure increased gradually from the central incisor, peaked at the canine or first premolar and decreased sharply-and significantly (P < 0·01)-towards the second molar. We conclude that the occlusal pressure of individual teeth can be used as an indicator of occlusal-supporting ability. This is therefore proposed as a possible suitable parameter for epidemiologic research, specifically for verifying the relationship between occlusal-supporting ability and status of residual periodontal ligament support.

Hardness, friction and wear studies on hydrogen peroxide treated bovine teeth

“…Wear tests were carried out over 1200 cycles with a constant load of 5 N. Although this force represents moderate contact forces between teeth [22,26], the corresponding maximum Hertzian contact pressure (assuming a Young's modulus of enamel of 50 GPa [31,32]) between the steel ball and tooth sample is about 430 MPa and 5-9 times higher than contact stresses measured during tooth clenching [33], thus reflecting a worst case simulation of tooth-tooth contact and attrition-induced wear. The chosen cycle number is equivalent to a total sliding distance of 2.4 m and reflects frequent tooth-tooth contacts in view of typical daily chewing rates [14,34,35].…”

Finite element analysis on tooth and periodontal stress under simulated occlusal loads

“…The mandibular first molar is the earliest permanent tooth appearing in the mouth and guides the development of the jaw . Analysis of its biomechanics provides understanding about tooth and periodontal functional patterns during chewing, and thus the evaluation of masticatory functions . To precisely define the stress/strain field of a molar during clenching, it is critical to build a model that incorporates the structure geometry, tissue properties and the acting forces on the mandibular system .…”

Proposed score for occlusal-supporting ability

“…Thus, we analyzed the occlusal force, area, and pressure of individual maxillary and mandibular teeth and assessed their OSAs. We concluded that the occlusal pressure of individual teeth can be used as an indicator of OSA [6].…”