Complete mandibular denture stability when posterior teeth are placed over a basal tissue incline

Area of Science:

• Dental Prosthetics
• Biomechanical Engineering
• Oral Rehabilitation

Background:

• Complete mandibular dentures require stable positioning for effective function.
• The placement of posterior teeth relative to the alveolar ridge can influence denture stability.
• Previous clinical observations suggest inclined tooth positioning may cause instability.

Purpose of the Study:

• To quantitatively assess the effect of posterior mandibular denture tooth positioning on denture movement during mastication.
• To investigate the destabilizing influence of teeth positioned over basal tissue inclines.
• To compare denture stability with teeth positioned over inclines versus adjusted positions.

Main Methods:

• Six patients with prior denture experience received new mandibular dentures.
• Metal markers were affixed to dentures and the mandible for tracking movement.
• Cineradiography captured chewing movements before and after adjusting posterior tooth positions relative to the alveolar ridge.

Main Results:

• Significant differences in cranial values (denture movement) were observed between the two chewing conditions.
• Denture movement values were consistently lower after posterior teeth were repositioned away from the inclined alveolar ridge.
• The adjusted tooth position resulted in demonstrably less denture displacement during function.

Conclusions:

• Positioning posterior denture teeth over basal tissue inclines of the mandibular alveolar ridge has a significant destabilizing effect.
• Adjusting tooth position to avoid inclined areas enhances mandibular denture stability during function.
• Findings support clinical observations and provide biomechanical evidence for optimal denture tooth placement.