Temporomandibular disorders and dental occlusion. A systematic review of association studies: end of an era?

Abstract

To answer a clinical research question: 'is there any association between features of dental occlusion and temporomandibular disorders (TMD)?' A systematic literature review was performed. Inclusion was based on: (i) the type of study, viz., clinical studies on adults assessing the association between TMD (e.g., signs, symptoms, specific diagnoses) and features of dental occlusion by means of single or multiple variable analysis, and (ii) their internal validity, viz., use of clinical assessment approaches to TMD diagnosis. The search accounted for 25 papers included in the review, 10 of which with multiple variable analysis. Quality assessment showed some possible shortcomings, mainly related with the unspecified representativeness of study populations. Seventeen (N = 17) articles compared TMD patients with non-TMD individuals, whilst eight papers compared the features of dental occlusion in individuals with TMD signs/symptoms and healthy subjects in non-patient populations. Findings are quite consistent towards a lack of clinically relevant association between TMD and dental occlusion. Only two (i.e., centric relation [CR]-maximum intercuspation [MI] slide and mediotrusive interferences) of the almost forty occlusion features evaluated in the various studies were associated with TMD in the majority (e.g., at least 50%) of single variable analyses in patient populations. Only mediotrusive interferences are associated with TMD in the majority of multiple variable analyses. Such association does not imply a causal relationship and may even have opposite implications than commonly believed (i.e., interferences being the result, and not the cause, of TMD). Findings support the absence of a disease-specific association. Based on that, there seems to lack ground to further hypothesise a role for dental occlusion in the pathophysiology of TMD. Clinicians are encouraged to abandon the old gnathological paradigm in TMD practice.

Prevalence of temporomandibular disorders in patients seeking orthodontic treatment: A systematic review

“…Conversely, the authors of 3 articles stated that open bite, deep bite, posterior crossbite and large interincisal angle appeared to be associated with TMD signs and symptoms. A recent systematic review on this subject concluded a lack of association between TMD and dental occlusion . Out of the 40 occlusal features being evaluated, only 2 (centric relation‐maximum intercuspation slide; mediotrusive interferences) were related to TMD.…”

“…Aetiological factors encompass macro‐trauma, micro‐trauma (eg bruxism and other parafunctions), psychological and somatic distress, and genetic factors . In contrast, the role of malocclusion, which traditionally had been regarded as one of the most important aetiological influences of TMD signs/symptoms, has been deemphasised . The decline of the importance of occlusal factors, however, does not imply that the dental occlusion has zero impact on TMD signs/symptoms .…”

Temporomandibular disorder symptoms and their association with quality of life, emotional states and sleep quality in South‐East Asian youths

“…They are the most common cause of non‐dental pain in the orofacial region . The aetiology of TMD is complex, multifactorial and consistent with the biopsychosocial model of illness, and its association with dental occlusion is debatable . Patients with TMD often present with jaw pain, earache, toothache, facial pain, headache or just facial fullness or pressure .…”

Indexes of jaw muscle function in asymptomatic individuals with different occlusal features

“…In dentistry, current knowledge suggests that contrarily to past beliefs, dental occlusion can have biological variations that should be considered physiological (i.e., not associated with signs and symptoms of dysfunction) independent on their specific configuration. Studies on the lack of association between dental occlusion and TMDs have thus diminished the etiological role of interarch relationships (Manfredini et al, ; Manfredini, Lombardo, & Siciliani, ; Manfredini, Lombardo, & Siciliani, ; Manfredini, Peretta, Guarda‐ Nardini, & Ferronato, ; Manfredini, Perinetti, & Guarda‐Nardini, ; Manfredini, Perinetti, Stellini, Di Leonardo, & Guarda‐Nardini, ). Nonetheless, a full comprehension of the interaction between the different components of the stomatognathic system is far from achieved.…”