Reliability of Measurements of the Occlusal Contact Area Obtained with an Occlusal Examination Device

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 46; no. 3; pp. 347 - 356
• Main Authors: Kawazoe, Takayoshi, Miyamoto, Mitsuru, Kashiwagi, Kosuke
• Format: Journal Article
• Language: Japanese
• Published: Japan Prosthodontic Society 10.06.2002
• Subjects: Dental Prescale System; generalizability theory; intra-rater reliability; occlusal contact area; occlusal examination
• ISSN: 0389-5386; 1883-177X
• DOI: 10.2186/jjps.46.347

Purpose: To investigate the intra-rater reliability of the occlusal contact area measured with an occlusal examination device of a pressure-sensitive sheet (Dental Prescale System (®) ) by using generalizability theory. Methods: Two occlusal conditions: medium clenching (MEC) and maximum (MAC), were selected. Subjects were ten males with healthy complete dentition. Measurement variability was estimated both among repetitions and between days using a repeated-measures study design, which provided 3 measurements during the same test, and 3 additional clenchings at a second test 7 days after the initial measurement. Generalizability study was used to assess the relative contribution of identified error sources (subject, occasion, and repetition) to the total measurement error. For intra-rater applications, an index of dependability, the standard error of measurement (SEM), and the smallest detectable difference (SDD) at the 0.05 level were estimated using decision study. Results: The measurement variability included two-way interaction components and a residual component, indicating that these interaction effects were important sources of measurement error. At least six measurements in MEC taken on two occasions (three measurements per occasion), and three measurements taken on a single occasion, or four measurements taken on two occasions (two measurements per occasion), for MAC, were necessary to obtain an index of dependability over 0.9. The SEM for an index of dependability over 0.9 was below 1.17mm2 for MEC and 1.89mm2 for MAC. Again, the SDD was below 3.24mm2 for MEC and 5.24mm2 for MAC. Conclusions: The clinical implication of these findings was that intra-rater reliability for occlusal contact area measurements could best be enhanced by averaging multiple measurements rather than by using a single measurement.