Temporomandibular Disorders among Dutch Adolescents: Prevalence and Biological, Psychological, and Social Risk Indicators

Table 1

Descriptive statistics of the predictor variables.

Independent variable
Age (years)	14.5 (±1.6)
Gender
Male	1,974 (50.1%)
Female	1,966 (49.9%)
Sleep bruxism
No	2,874 (82.0%)
Yes	633 (18.0%)
Awake bruxism
No	3,334 (90.0%)
Yes	372 (10.0%)
Chewing gum
No	261 (6.2%)
Yes	3,943 (93.8%)
Biting nails
No	2,105 (50.0%)
Yes	2,104 (50.0%)
Biting pens and pencils
No	2,397 (56.9%)
Yes	1,819 (43.1%)
Biting lips and/or cheeks
No	1,793 (42.6%)
Yes	2,414 (57.4%)
Smoking cigarettes
No	3,658 (86.7%)
Yes	559 (13.3%)
Alcohol consumption
No	2,166 (51.4%)
Yes	2,046 (48.6%)
Being stressed
No	1,680 (39.9%)
Yes	2,534 (60.1%)
Feeling sad
No	2,183 (51.8%)
Yes	2,030 (48.2%)
School type
Lower levels	2,386 (56.3%)
Highest level	1,849 (43.7%)
Ethnic background
Native Dutch	3,368 (82.0%)
Nonnative Dutch	740 (18.0%)

The dichotomized categorical variables are presented as absolute numbers (ratio); age is presented as mean value (±standard deviation).