Evidence-based versus experience-based views on occlusion and TMD

Abstract

There is an old adage: never discuss divergent views concerning religion and politics with friends; you could lose a friend and create an enemy. Perhaps a variation on this notion applies to certain topics in dentistry and orthodontics. To this end, an acrimonious environment will surely ensue in the dental community when contending views are expressed about such topics as occlusion, temporomandibular disorders (TMDs), condyle position, gnathology, and mounted casts. Particularly sensitive to divergent thoughts on these topics are those who adhere to what is generally described as gnathology. Convinced of their “experience-based” views, they readily excuse away the contrary “evidence-based” (scientific) data. As Greene et al wrote, “Some clinicians are vocal critics of the TMD research community, arguing that clinicians’ anecdotal experiences are more valid than the contradictory research findings.” Even though the evidence points clearly toward occlusion having a secondary role in TMD, they still view occlusion as the primary and perhaps the single cause of TMD. This might be somewhat understandable if one agrees with Vig’s general view concerning some orthodontists: “orthodontists have lain greater emphasis on mastering their art than mastering their science. . . . There are many orthodontic controversies, past and present, that center on whose art is superior.” In a similar manner, Johnston argued: “Those who advocate new therapies seem disinclined to provide the evidence of efficacy (it may be bad for business), and the profession as a whole, perhaps being convinced in dental school of the irrelevance of ‘science,’ seems equally disinclined to demand it.” The experience-based and evidence-based views