A comparative study on dynamic occlusal adjustment based on mandibular movement trajectories and virtual articulators...

Area of Science:

• Digital dentistry and prosthodontics
• Computer-aided design/computer-aided manufacturing (CAD/CAM)
• Occlusal analysis and adjustment

Background:

• Accurate occlusal adjustment is critical for the longevity and function of dental restorations.
• Traditional occlusal adjustment methods can be time-consuming and subjective.
• Digital workflows offer potential for improved precision and efficiency in occlusal adjustment.

Purpose of the Study:

• To compare the performance of three dynamic occlusal adjustment methods: virtual articulator with default parameters (VAD), virtual articulator with individual parameters (VAI), and mandibular movement trajectories (MMT).
• To evaluate the occlusal accuracy of these methods on single crowns (SC) and three-unit splinted crowns (TUC).

Main Methods:

• Intentional occlusal interferences were introduced into 20 SCs and 20 TUCs.
• Adjustments were performed using VAD, VAI, and MMT within Exocad software.
• Occlusal surfaces were analyzed in Geomagic using closest-point distance mapping to calculate mean deviation (MD) and root mean square (RMS).

Main Results:

• MMT demonstrated significantly lower MD and RMS values for both SCs and TUCs compared to VAD and VAI (p<0.05).
• No significant difference in MD or RMS was found between VAD and VAI (p>0.05).
• MMT achieved a higher proportion of distance deviations within the optimal range (-0.1 to 0.1 mm) compared to VAD and VAI (p<0.01).

Conclusions:

• Dynamic occlusal adjustment methods significantly impact the occlusal design of posterior dental restorations.
• MMT-based adjustment provides superior occlusal accuracy compared to VAI and VAD.
• Integrating patient-specific mandibular movement trajectories into digital workflows enhances occlusal adjustment performance.