Date of Award
Spring 1995
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Ferguson, Donald J.
Second Advisor
Schuckit, William I.
Third Advisor
Kittleson, Russell T.
Abstract
Many types of articulators designed to replicate the movement of the mandible in relation to the maxilla are in existence today. The Polycentric Hinge Joint articulator (POLY), a relatively new concept in articulators, is promoted as an instrument that more precisely replicates the anatomy and function of the temporomandibular joint and mandible. It is presumed that the more closely an articulator mimics the TMJ complex, the more likely it is to replicate mandibular movement. Whereas the SAM 2 (one of the most popular semi-adjustable articulators in orthodontics) utilizes a spherical ball Which functions against a flat surface, the POLY uses an angled, cylindrically shaped condyle which functions in a trough shaped fossa, thereby making polycentric movement possible. The purpose of this study was to compare the accuracy of cone-splints made on the POLY versus the SAM 2 from study casts mounted in centric occlusion. (Five acrylic cones were added to a maxillary baseplate to contact specific mandibular teeth at an overall opening of about 8 mm.) In theory, an articulator which more accurately replicates mandibular movement should produce a more accurate cone-splint. Twenty adult subjects with a mean age of 28.6 years volunteered to participate in the study at the Marquette University, School of Dentistry, Orthodontic Department. The sample consisted of eleven males and nine females, and the subjects had no signs nor symptoms of temporomandibular joint dysfunction. As a blind study, cone-splint appliances were fabricated in the lab by a second operator. They were then inserted, and the cone-to-tooth gap distances between the cones and select mandibular teeth were measured. The cone-splints made on the two articulators performed in a similar manner except for cone number 2. The cone-to-tooth gap distance for the right cuspid cone was statistically smaller for the POLY (p = .046) upon comparison with the paired t-test. In general, the cone-splint appliances fabricated on the POLY were more accurate than the appliances fabricated on the SAM 2.
Recommended Citation
Wilke, Kevin James, "Articulator Accuracy in Fabricating Maxillary Splints Utilizing Centric Occlusion Records: Polycentric Hinge vs. SAM 2" (1995). Master's Theses (1922-2009) Access restricted to Marquette Campus. 5476.
https://epublications.marquette.edu/theses/5476