06/08/2011 Predictors of Bruxism, Other Oral Parafunctions, and Tooth Wear over a 20-Year Follow-up Period

Resident: J. Hencler
Date: 06/08/2011

Article title: Predictors of Bruxism, Other Oral Parafunctions, and Tooth Wear over a 20-Year Follow-up Period

Author: Carlsson et al
Journal: Journal of Orofacial Pain Volume 17, Number 1, 2003

Major topic: Oral parafunctions

Type of Article: Longitudinal study

Main Purpose:
Analyze predictors of bruxism, other oral parafunctions, and anterior tooth wear by the use of logistical regression models w/ variables recorded at the first exam as independent variable.

Overview of method of research:
Originally 402 randomly selected 7-, 11-, and 15-year old patients were examined clinically and by questionnaire. Twenty years later 320 completed and returned the questionnaire. 100 returned patients underwent a clinical exam focusing on occlusal factors and function/dysfunction of the masticatory system. For analyses of predictors of oral parafunctions and tooth wear registered at the 20 yr f/u, logistic regression was used w/ recordings at the first exam as independent variables.

Findings:
The bivariate analyses between the dependent variable (reported bruxism at 20 year f/u) and selected variables from the first exam 20 years earlier resulted in five significant associations. These 5 variables (reported bruxism and other oral parafunctions, headache, pain after heavy chewing, TMD symptoms including pain after chewing) plus 1 dental variable (anterior open bite) were included in the logistical regression model with reported bruxism at the 20 year f/u as the dependent variable. See tables for details.

Key points in the article discussion:
The hypothesis was that bruxism and other oral parafunctions in childhood would be identified as predictors of bruxiam and other oral parafunctions and tooth waer 20 years later. Many clinicians have suggested a positive between relationship bruxism and TMD but the knowledge of what causes TMD is limited. The etiology of bruxism has also been controversial and theories have considered occlusal, psychological, genetic, and stress factors. Currently, there is a concensus about the multifactorial nature of its etiology, and bruxism is thought to be a CNS phenomenon related to stress and pain behavior more than to structural components.

Summary of conclusions:
This study found:
1) Reports in childhood bruxism, tooth clenching, tooth grinding at night and nail biting and/or other parafunctions were predictors of the same oral parafunctions 20 yrs later. This suggests that oral parafunctions may be a persistent trait in many subjects
2) Predictors of the 2 components of bruxism, tooth clenching during daytime and tooth grinding at night, were not the same, which supports the opinion that these 2 occlusal parafunctions may be different
3) Postnormal occlusion (Class II) and tooth wear in childhood predicted increased tooth wear in adulthood
4) Nonworking-side interference reduced the risk for extensive tooth wear of the anterior teeth in 100 35-year old subjects.

Assessment of article:
Interesting conclusion. I find that many parents report that their children grind their teeth and want to know if there are any specific causes and possible treatment to make them stop. I find the answer to this question one of the more difficult to explain to parents because we don’t really know the answer for sure. Usually occlusal guard or TMJ therapy is not indicated in very young patients so the best we can do is encourage the parents and continue to monitor the bruxism.