Oral Jaw Behaviors in TMD and Bruxism: A Comparison Study by Severity of Bruxism

ABSTRACT

The purpose of this study was to document the prevalence of oral jaw behaviors concomitant to bruxism in TMD+bruxing behavior patients and in nonbruxer controls. Clinical examination, questionnaires, and specific criteria to allocate patients to mild, moderate, and severe groups of TMD and bruxers were used. The sample consisted of 274 TMD + bruxing behavior patients and 52 control non-bruxing behavior groups evaluated at the Center for the Study of TMD. The mean age of the TMD+ bruxing behavior group was about 33.11 years old (range 16.66, SD = 11.52) as compared to 34.90 years old (range 17–67, SD = 14.26) in the control group. Oral jaw behaviors were assessed in the mild, moderate, and severe TMD+bruxing groups, and in the corresponding control group. It was found that the prevalence of oral jaw behaviors was higher in the TMD+bruxing behavior group as compared to the control. Hence, concomitant oral jaw behaviors predominated in bruxers and increased with its severity. The data reinforce the need to assess TMD patients in terms of the presence of bruxism, its severity, and concomitant oral jaw habits. Such approach will enable the clinician to have better understanding about the role of these behaviors in TMD. Epidemiological data was also provided regarding jutting the jaw forward (a rarely-described oral jaw habit) in a relatively large sample of TMD+bruxing patients, suggesting a more clinical intervention in children and adolescents. This study is the first to document the prevalence of specific oral jaw habits in a relatively large sample of TMD+bruxing behavior classified by degree of severity. Results suggest that TMD+bruxing patients may present many other additional oral jaw habits which may concur to increase masticatory muscle activity thus leading to TMD signs and symptoms. Factors responsible for the increased frequency of oral jaw habits with the severity of bruxism behavior remain unknown and therefore further studies are needed.

Additional information

Notes on contributors

Omar Franklin Molina

Dr. Omar Franklin Molina received his D.D.S. degree in 1978 at the State University, Rio Grande do Sul, Brazil, a Masters Degree in 1983 at the State University of Santa Catarina, Brazil, and a specialization in orthodontics at the State University of Rio de Janeiro, Brazil in 1984. He is a member of the American Equilibration Society and of the Center for Study of Craniomandibular Disorders at Porto Alegre, Brazil. He has presented lectures on occlusion, facial pain, and parafunctional habits in Brazil and the United States, published three hooks on TMD and co-authored a book in orthodontics, and many articles. Currently, Dr. Molina is an associate professor at the University of Texas Health Science Center at San Antonio, Texas and a clinical professor at the School of Continuing Education in Cascavel, Parana, Brazil.

José dos Santos

Dr. Jose dos Santos, Jr. received his D.D.S. degree in 1959 at the University of Sãn Paulo, Dental School, Brazil and a Masters Degree in Restorative Dentistry from the Rackham Institute of Graduate Studies, University of Michigan. He was a Associate Professor at the University of Sãn Paulo, Dental School from 1962 to 1979., and is a former Associate Professor at the Department of Occlusion and Orofacial Pain/Temporomandibular Joint Clinic at the University of Michigan, School of Dentistry (1980 to 1988). Currently Dr. dos Santos is a Professor at the University of Texas Health Science Center at San Antonio. He is the Director of Programs for Continuing Education for Brazilian Dentists in the United States. He has published several books and articles both nationally and internationally. He has lectured both nationally and internationally in the field of occlusion.

Marcelo Mazzetto

Dr. Marcelo Mazzetto is a Professor of Prosthodontics and Occlusion at the University of Sao Paulo in Ribeirao Preto (Brazil) where he received his D.D.S. degree in 1978, Master of Science in Prosthodontics in 1982, and Ph.D. in 1990 from the same university. He has authored three books on occlusion and TMD and has published papers in the United States and Brazil. He lectures extensively in Brazil and maintains a private practice devoted to TMD and Facial Pain in Ribeirāo Preto.

Stanley Nelson

Dr. Stanley J. Nelson is currently an Associate Professor in the Division of Occlusion, Department of Restorative Dentistry, University of Texas Health Science Center at San Antonio. He received his D.D.S. in 1979 and his M.S. degree in Restorative/Occlusion in 1986 from the University of Michigan School of Dentistiy, where he also served as faculty in the School's Department of Occlusion. Dr. Nelson has published numerous scientific articles and is currently serving on the Board of Directors of the American Equilibration Society.

Thomas Nowlin

Dr. Thomas P. Nowlin is a Professor and Head of the Division of Occlusion at The University of Texas Health Science Center. He received his dental training at The University of Texas Dental Branch at Houston in 1970 and his Master's in Education with an emphasis in college and university curriculum and instruction in 1981. He has been active in curriculum design and planning, recently chairing the Curriculum Planning Committee for three years, and has presented nationally on Curriculum Evaluation and Outcomes Assessment as a basis for planning.

Ézio T. Mainieri

Dr. Ézio Mainieri received his D.D.S.from the State University of Rio Grande do Sul (Brazil) in 1970. In 1979, received an M.S. degree in Prosthodontics at Indiana University. He is currently Chairman of a two-year program in Prosthodontics at the same university in Brazil. He published about 70 scientific papers, has lectured extensively in his native country and authored three books on the subject of Fixed and Removable Prosthodontics. He also maintains a private practice in Porto Alegre, Brazil.