Introduction

Current Issues in Occlusion

Occlusion plays a central role in the practice of dentistry. However, the scientific basis for many occlusal procedures has remained controversial. For example, in the 1980s, occlusion was popular as testimonials supported its importance in oral rehabilitation, periodontal disease progression, and craniomandibular pain. Empirical theories and clinical strategies were developed that perhaps overstated the importance of occlusion.

In the late 1980s, epidemiological studies questioned the scientific basis for many relationships between occlusion and dysfunction. This resulted in confusion, a loss of interest, and even a backlash in the sentiment of the profession. Within a short period, the topic of occlusion was not only unpopular, but also considered unscientific and superficial hyperbole. The goal of this issue is to emphasize that occlusal considerations are important and that science has shown a well-established association between occlusion and dental health.

This issue of the Journal of the California Dental Association includes five papers intended to update practitioners with new information about the relevance of dental occlusion to their practice. The first article describes the evolution of numerous theories, techniques, and treatment philosophies as related to occlusion. Though some of these ideas have been disproved, others remain empirically true, while others have been validated by scientific evidence.

The second article outlines how occlusion can affect treatment prognosis. As the tooth-periodontium apparatus weakens through disease and over time, adaptive changes occur in response to occlusal force. Strategies for improved adaptive response are discussed. This article takes an original approach in looking at occlusal force as a prognostic determinant of treatment outcome.

The third article reviews the use of dental implants in the partially edentulous patient. The article emphasizes the importance of treatment planning and how attention to occlusal relations can decrease restorative complications. Both the type and frequency of restorative complications are reviewed, as are considerations for splinting and cantilevers with implant restorations.

The fourth article outlines why most referrals for orthodontic treatment are occlusion-related and why the importance of occlusion continues to be controversial in orthodontics. The six warning signs of a child with a developing malocclusion are reviewed, and how unfavorable growth patterns can be altered with early treatment is emphasized. Included is a discussion of current thinking on the relationship between temporomandibular joint dysfunction and orthodontics.

The last article offers the clinician a simple and practical classification system that can assist in the diagnosis, treatment planning, and management of occlusion. This classification system has been successfully used in our teaching program at UCSF.

We hope you enjoy and benefit from this issue on occlusion.

Contributing Editor

Donald A. Curtis, DMD, is a professor in the Department of Preventative and Restorative Dental Sciences at the University of California at San Francisco School of Dentistry.

Author

Richard T. Kao, DDS, PhD, is an associate adjunct professor in the Periodontology Department at the University of the Pacific and currently has a private practice limited to periodontics and dental implants in Cupertino, Calif. He is a diplomate of the American Board of Periodontology.