TABLE 1.
Exploratory factor analysis of OBC items
| Items | Description of items | Factor 1 | Factor 2 |
|---|---|---|---|
| OBC_3 | Grind teeth together during waking hours | 0.72 | |
| OBC_4 | Clench teeth together during waking hours | 0.78 | |
| OBC_5 | Press, touch or hold teeth together other than while eating (that is, contact between upper and lower teeth) | 0.68 | |
| OBC_6 | Hold, tighten or tense muscles without clenching or bringing teeth together | 0.68 | |
| OBC_7 | Hold or jut jaw forward or to the side | 0.61 | |
| OBC_8 | Press tongue forcibly against teeth | 0.48 | |
| OBC_9 | Place tongue between teeth | 0.46 | |
| OBC_10 | Bite, chew or play with your tongue, cheeks or lips | 0.55 | |
| OBC_11 | Hold jaw in rigid or tense position, such as to brace or protect the jaw. | 0.62 | |
| OBC_12 | Hold between the teeth or bite objects such as hair, pipe, pencil, pens, fingers and fingernails | 0.54 | |
| OBC_13 | Use chewing gum | 0.50 | |
| OBC_14 | Play musical instrument that involves use of mouth or jaw (e.g., woodwind, brass, string instruments) | ||
| OBC_15 | Lean with your hand on the jaw, such as cupping or resting the chin in the hand | ||
| OBC_16 | Chew food on one side only | ||
| OBC_17 | Eating between meals (i.e., food that requires chewing) | 0.51 | |
| OBC_18 | Sustained talking (e.g., teaching, sales, customer service). | 0.49 | |
| OBC_19 | Singing | 0.57 | |
| OBC_20 | Yawning | 0.57 | |
| OBC_21 | Hold telephone between your head and shoulders | ||
| Eigen | 4.4 | 1.8 | |
| Cumulative percentage | 47% | 82% |
OBC items in analysis are related to waking oral behaviours. The exploratory factor analysis (EFA) is based on polychoric correlation matrix and varimax rotation of factor loadings. Items with a loading factor lower than 0.45 were omitted and not listed. The last two rows represent eigenvalue, and cumulative percentage of factors 1 and 2 is reported at the bottom of the table.