Reduced Periodontal Support for Lower Central Incisor - A 3D Finite Element Analysis of Compressive Stress in the Periodontium.

Background: The aim of this study was to assess the stress concentration in simulated periodontal alveolar bone containing healthy teeth with and without attachment loss.

Methods: Six 3-D models of a lower central incisor were created simulating the teeth structure, cancellous and cortical bone and periodontal ligament. Each model presented a 1mm increasing distance between cement-enamel junction (CEJ) and alveolar bone crest (ABC) (1 to 6mm). A 100N, 45-degree load was applied to the buccal face of the lower central incisor. The effects of Minimum Principal Stress (MPS) on lamina dura (LD) and ABC were analyzed.

Results: The results showed an increase of MPS in the surrounding bone (ABC and LD) due to periodontal attachment loss. The 6mm attachment loss model showed the highest (p less than 0.001) magnitude in MPS. Each millimeter increase in CEJ-ABC distance generated a 12% pattern of attachment loss and an increase at least of 65.7% for ABC and 33.6% for LD.

Conclusion: Under simulated conditions, attachment loss increases stress concentration in the surrounding bone suggesting a partly explanation regarding bone resorption risk for teeth with periodontal attachment loss.