Orthodontic dental casts: The case for routine articulator mounting

Abstract

To mount or not to mount: that is the question. The famous quotation from Hamlet, slightly transformed, continues: “Whether ’tis nobler in the mind to suffer the slings and arrows of outrageous fortune, or to take arms against a sea of troubles, and by opposing end them. To die, to sleep. Of course, the question of whether to mount dental casts is not worth “suffering slings and arrows,” nor is it worth getting depressed, and certainly we should not commit suicide over it! After all, it’s only an articulator; yes, there are many reasons why we should mount models on an articulator, but let’s think about its clinical importance, use some logical thinking, and take away the passion. To better understand this Point/Counterpoint discussion, we should avoid relating the use of an articulator to a group, a philosophy, or a guru. It is simply what is best for the patient. Researchers have reported that the use of an articulator is not evidenced-based, as stated by Rinchuse and Kandasamy in their article, “Articulators in orthodontics: an evidence-based perspective.” Evidence-based research needs to be put in the proper clinical context. The most relevant question is whether research is always good for clinical practice. This implies that the clinical reality to which it is applied should not be misrepresented to satisfy the demands of the research. Use of the term “evidenced-based” in position-statement papers only confuses the situation. From a clinical perspective, several points should be considered. The articulator is only a clinical tool that we can use to obtain a more complete diagnosis. The more information we have about the patient, the better our diagnosis and eventual treatment. Therefore, concerning its use, it is not a matter of yes or no but, rather, why not? An orthodontist can do good orthodontics without using an articulator, but an articulator can help him or her provide better treatment in many clinical situations. The articulator provides an added dimension that helps in gathering more information by visualization of the pretreatment occlusion in static occlusion, and permits the visualization of various functional movements. In prosthodontics, once the musculoskeletal stable position has been obtained and the patient’s dental casts are mounted on the articulator, posterior teeth can be removed. It is then possible to determine whether the origin of the malocclusion is horizontal, vertical, or transverse. Knowing this in many Angle Class II cases will prevent the clinician from trying to do the impossible in correcting the malocclusion. By doing this easy step in diagnosis, we know the limitations even before placing the first bracket. This information is impossible to obtain with hand-held dental casts, and most orthodontic failures are due to an incomplete diagnosis and not determining the origin of the malocclusion before treatment. Mounted dental casts are an aid to a more complete diagnosis. The following is a list of many important reasons for mounting dental casts on an articulator. 1. It helps in measuring the centric relation-centric occlusion discrepancy in 3 planes of space. This is important information when the goal is to treat to a musculoskeletal stable position. 2. It helps in determining the first contact point (fulcrum point) in centric relation. This is particularly important in patients with a reduced posterior vertical dimension and a vertical or clockwise pattern of growth. This gives a realistic picture of the vertical control mechanics that must be used to correct the malocclusion. 3. It helps in studying the attrition patterns and the proclination of the maxillary incisors in periodontal patients. 4. It helps in determining the need for “trial” treatments. A diagnostic setup on mounted dental casts is often necessary in patients with tooth-size discrepancies. We can determine the needed changes before our actual treatment. Specialist in orthodontics, San Sebastian, Spain. Specialist in orthodontics, Parma, Italy. Reprint requests to: Domingo Martin, Plaza Bilbao 2-2 , San Sebastian, Spain; e-mail, martingoenaga@arrakis.es. Am J Orthod Dentofacial Orthop 2012;141:8-17 0889-5406/$36.00 Copyright 2012 by the American Association of Orthodontists. doi:10.1016/j.ajodo.2011.11.007