Mediotrusive Occlusal Contacts: Best Evidence Consensus Statement.

ABSTRACT

PURPOSE: The impact of mediotrusive (MT) occlusal contacts has been a topic of controversy and confusion in both clinical practice and in the dental literature. The purpose of this Best Evidence Consensus Statement was to explore whether MT interferences are harmful in the natural or therapeutic occlusion directed by 4 focus questions relating to prevalence, jaw function, jaw dysfunction and biomechanical models. MATERIALS AND METHODS: An electronic search in October 2020 sought evidence in MEDLINE (Ovid) using (mediotrus* OR nonworking side OR nonworking contact OR balancing side OR interfer* side OR premature contact) in the multipurpose (.mp) search field; and in Google Scholar using permutations of the above. Supplementary articles were sourced from the associated reference lists. There was no language restriction. The search yield was reviewed in duplicate. RESULTS: The electronic search identified 420 articles. Following screening, 164 were selected for eligibility assessments. Of these, 47 were included in the current paper. CONCLUSIONS: Non-standardized nomenclature and methodology is used to identify MT interferences in patient populations, with resultant prevalence varying from 0% to 77%, (median = 16%). MT interferences may alter the biomechanics of mandibular function. Together with the presence of repeated high loads resultant strain can manifest as pathophysiology of the temporomandibular joint and associated muscle structures. MT interferences should be avoided in any therapeutic occlusal scheme to minimize pulpal, periodontal, structural and mechanical complications or exacerbation of temporomandibular disorders (TMDs). Naturally occurring molar MT interferences should be eliminated only if signs and symptoms of TMDs are present. Literature supports there being a biomechanical basis which can explain how MT interferences may affect temporomandibular joint morphology and jaw function.