The influence of traumatic occlusion on the repair process for teeth following subluxation

Background/aim: Traumatic occlusion (TO) can cause morphofunctional alterations that interfere in the homeostasis of the periodontium. The aim of this study was to assess the influence of TO on the periodontal repair process for teeth following subluxation.

Materials and methods: Ninety Wistar rats aged 12 weeks were divided into three groups: control (C), subluxation (S) and subluxation with traumatic occlusion (S+TO). Subluxation was created with an impact force of 900 cN applied by a tensiometer and TO was created with a direct composite resin filling. Healing after two experimental periods of 7 and 21 days was assessed histologically. The Kruskal-Wallis and Dunn post hoc tests were used for group comparison.

Results: At 7 days, there was a significant increase in periodontal ligament (PDL) width and amorphous fundamental substance, as well as a significant bone area reduction in groups S and S+TO. After 21 days, there was a significant PDL width increase in group S+TO, and in the percentage of collagen fibres in group S, whereas group S+TO showed a 52% bone area reduction compared to the same group at 7 days. Subluxation with or without TO caused only superficial root resorption. However, only group S+TO showed damage to the repair process of resorbed root areas after 21 days.

Conclusion: TO can increase damage to the PDL after subluxation and it can also delay the repair process after PDL damage.