Study of the number of occlusal contacts in maximum intercuspation before orthodontic treatment in subjects with Angle Class I and Class II Division 1 malocclusion

Gustavo Adolfo Watanabe-Kanno,Jorge Abrão

doi:10.1590/s2176-94512012000100017

Gustavo Adolfo Watanabe-Kanno, Jorge Abrão

Open Access

https://doi.org/10.1590/s2176-94512012000100017

Copy DOI

Abstract

Objective: Define and compare numbers and types of occlusal contacts in maximum intercuspation. Methods: The study consisted of clinical and photographic analysis of occlusal contacts in maximum intercuspation. Twenty-six Caucasian Brazilian subjects were selected before orthodontic treatment, 20 males and 6 females, with ages ranging between 12 and 18 years. The subjects were diagnosed and grouped as follows: 13 with Angle Class I malocclusion and 13 with Angle Class II Division 1 malocclusion. After analysis, the occlusal contacts were classified according to the established criteria as: tripodism, bipodism, monopodism (respectively, three, two or one contact point with the slope of the fossa); cuspid to a marginal ridge; cuspid to two marginal ridges; cuspid tip to opposite inclined plane; surface to surface; and edge to edge. Results: The mean number of occlusal contacts per subject in Class I malocclusion was 43.38 and for Class II Division 1 malocclusion it was 44.38, this difference was not statistically significant (p>0.05). Conclusions: There is a variety of factors that influence the number of occlusal contacts between a Class I and a Class II, Division 1 malocclusion. There is no standardization of occlusal contact type according to the studied malocclusions. A proper selection of occlusal contact types such as cuspid to fossa or cuspid to marginal ridge and its location in the teeth should be individually defined according to the demands of each case. The existence of an adequate occlusal contact leads to a correct distribution of forces, promoting periodontal health.

Highlights

MethodsThe study sample consisted of 26 untreated subjects, 20 males and 6 females, Caucasians, with ages between 12 and 18 years, at beginning of orthodontic treatment
The Kolmogorov-Smirnov test demonstrated that values had a normal distribution (p>0.05), comparisons between malocclusion values were performed with parametric tests based on the sample distribution
The comparison between the mean occlusal contacts in Maximum intercuspation (MI) on the upper and lower arches, according to the malocclusion is described in Table 2, and demonstrated that:

Summary

Methods

The study sample consisted of 26 untreated subjects, 20 males and 6 females, Caucasians, with ages between 12 and 18 years, at beginning of orthodontic treatment. The patients were diagnosed and grouped into 13 with Angle Class I malocclusion and 13 with Angle Class II Division 1 malocclusion, from the Orthodontic Clinic of the Dental School of São Paulo University, following these criteria: Complete permanent dentition with erupted second molars, no caries lesions, no interproximal wear, no extractions nor previous orthodontic treatment, healthy periodontal status and absence of temporomandibular joint dysfunction symptoms. Occlusal contact points were determined clinically on patients with the aid of articulated dental casts. The patient was put in a vertical position, with the back and head on a reclined dental chair, approximately 45 degrees to the floor. The patient was asked to open and close his mouth until MI was reached. After prophylaxis and drying of all teeth, the patient was asked to open and close his mouth

Results

Discussion

Conclusion