The biological effects of occlusal trauma on the stomatognathic system - a focus on animal studies

The aim of this review of the literature was to assess the biological effects of occlusal trauma on the stomatognathic system focusing on animal studies. However, there are no conclusive explanations on the association between occlusal trauma and disease of the stomatognathic system. A literature survey was performed using the Medline database, covering the period from 1967 to 2012. Over 300 abstracts were reviewed, and 70 manuscripts were selected. Additional references from citations within the articles were obtained, and current textbooks were also used. This review does not include the effects of occlusal trauma on dental implants or dental prostheses/appliances. A total of 70 full articles were included for the final analysis. The selected 70 articles were classified into the following five categories, including the effects of occlusal trauma on the pulp tissues, periodontal tissues, masticatory muscle, temporomandibular joint (TMJ) and central nervous system (CNS). It was demonstrated that occlusal trauma caused a variety of harmful biological effects on stomatognathic system. Additionally, occlusal trauma could lead to some pain substance changes in the pulp, periodontal tissues, masticatory muscle, TMJ and CNS, which was possibly related to the peripheral and the central neuronal sensitisation. However, these findings demonstrate that there are remaining disagreements by various authors. More randomised trials are needed to validate these effects.