Assessment of occlusal interferences.

Area of Science:

• Dental Occlusion
• Clinical Measurement Reliability
• Observer Variability in Dentistry

Background:

• Accurate assessment of occlusal variables is crucial for diagnosing and treating dental malocclusions.
• Variability in observer interpretation can impact the reliability of occlusal assessments.
• Understanding observer error is essential for standardizing diagnostic procedures in dentistry.

Purpose of the Study:

• To investigate the variability in the assessment of key occlusal variables by multiple observers.
• To evaluate the intra- and inter-observer reliability for measurements of jaw position and occlusal interferences.
• To determine the acceptability of observer error for future clinical research in occlusion.

Main Methods:

• Eight subjects underwent repeated occlusal registrations by four independent observers.
• Measurements included sagittal, vertical, and lateral sliding between retruded contact position (RCP) and inter-cuspal contact position (ICP).
• Occlusal interferences during lateral movements (working and balancing sides) and protrusive deviations were recorded.

Main Results:

• Intra- and inter-observer error for sagittal and vertical RCP-ICP distance measurements were within acceptable limits.
• High intra- and inter-observer agreement was found for lateral RCP-ICP distance, irrespective of measurement modality.
• Inter-observer agreement was lower for balancing side interferences, with consensus only on movements >3mm; working side interferences showed acceptable error, while protrusive deviation measurement error was larger.

Conclusions:

• Most assessed occlusal variables, including RCP-ICP distances and working side interferences, demonstrate acceptable reliability for research purposes.
• Balancing side interferences and lateral mandibular deviation during protrusion present higher observer variability, requiring careful consideration.
• Standardized training and clear diagnostic criteria are recommended to minimize observer error in complex occlusal assessments.