Prevalence of temporomandibular disorders: samples taken from attendees of medical health-care centers in the Islamic Republic of Iran.

AIMS: To determine the prevalence of facial pain and temporomandibular disorders (TMD) in people located in urban and rural areas in a newly industrialized country (Iran). METHODS: Two-hundred twenty-three subjects between 18 and 65 years of age (mean: 32.07; SD: 10.83) were randomly selected from an urban area and a rural area. One-hundred nineteen subjects from Mashhad (major city) and 104 subjects from Zoshk (village) were voluntarily recruited from medical health-care centers. Subjects who consulted the health-care center for dental, ear, nose, or throat issues were excluded. The monitoring of public health attendance of all citizens at designated health-care centers is compulsory by local law. All subjects were examined in accordance with the Research Diagnostic Criteria for TMD (RDC/TMD). Facial pain was assessed by using a questionnaire; the prevalence of myofascial pain, disc displacement, and degenerative disorders was determined by clinical examination. Nonparametric tests were used to assess group differences (ie, between village and city). RESULTS: Subjects in urban areas suffered less from facial pain (20.2% versus 46.2%; P < .01 [Mann-Whitney U test]) than subjects in rural areas. The frequency of TMD, disc displacement, and degenerative disorders was greater in the rural area. CONCLUSION: The symptoms under investigation were significantly more widespread in rural than in urban areas. With regard to TMD per se, the place of residence appears to be unimportant. However, the rural population was significantly affected by facial pain.

Intraexaminer reliability of measurement of tooth color by spectrophotometry.

OBJECTIVE: To evaluate intraexaminer reliability in measurement of basic tooth color by use of a clinically applicable spectrophotometer. METHOD AND MATERIALS: Three examiners determined the L* (lightness), C* (chroma), and h* (hue) values and tooth color according to the Vita 3D-Master shade guide system (Vident), twice for 161 anterior teeth of 19 subjects by use of a spectrophotometer (Vita Easyshade 1, Vita Zahnfabrik). Between the 2 measurements on each tooth, the investigators had to completely remove the probe tip from the mouth. The reliability of the measurements was observed, and deviations between the 2 L*C*h* measurements, as well as DeltaEab for the measurements, were calculated. RESULTS: Exact agreement of chosen shade tab according to the 3D-Master shade guide was achieved in 48% of cases. Mean DeltaL*, DeltaC*, and Deltah* for all examiners were 1.9 (SD 1.7), 1.3 (SD 1.3), and 0.5 degrees (SD 0.7 degrees), respectively. The maximum deviation was 9 for DeltaL*, 7 for DeltaC*, and 3 degrees for Deltah*. Mean DeltaEab for the measurements was 2.7 (SD 1.8, range 0 to 9.5). CONCLUSION: Intraexaminer reliability was usually acceptable, although a clinically relevant difference between the 2 measurements of an examiner was occasionally observed. This uncertainty should be borne in mind in clinical routine and in studies reporting changes in color, eg, studies of tooth bleaching.

Interexaminer reliability in clinical measurement of L*C*h* values of anterior teeth using a spectrophotometer.

PURPOSE: The objective of this study was to investigate interexaminer reliability in the clinical measurement of the L*C*h* (lightness/value, chroma, hue) values of anterior teeth using a spectrophotometer (Vita Easyshade). MATERIALS AND METHODS: The basic color of the maxillary right central incisors and canines of 23 subjects was spectrophotometrically determined by 4 clinicians and an experienced user (development manager) of the spectrophotometer. Also, to analyze the effect of different training with the instrument on interexaminer reliability, 2 of the clinicians were instructed in the use of the spectrophotometer by the experienced examiner, whereas the others instructed themselves by studying the operating manual. RESULTS: Agreement between all examiners was acceptable to excellent (intraclass coefficient > 0.4). The mean value of the measured differences for the central incisors of all subjects for L* values was 5 (for C* = 3.8, h* = 2.7 degrees) and for canines, the mean L* was 4.5 (C* = 3, h* = 1.6 degrees). Results from comparison of the 2 different training methods were inconsistent. Agreement with the experienced examiner ranged from not acceptable (C* values for incisors of self-instructed examiners) to excellent. CONCLUSION: The distribution of the measurements of 1 subject could lead to deviations in color, probably with clinical impact. For canines, the measurements were at least equally reproducible (in some cases significantly more reproducible) compared to central incisors. Because of the small number of examiners and the inconsistent results, it was not possible to reach a definite conclusion about the effect of different training methods on interexaminer reliability.