A study of anterior guidance

Area of Science:

• Dental Anatomy
• Biomechanical Analysis
• Tooth Morphology

Background:

• Understanding the lingual surface morphology of maxillary anterior teeth is crucial for dental restorations and orthodontic treatments.
• Previous research has not fully detailed the curvature and inclination of these surfaces in relation to occlusal function.

Purpose of the Study:

• To quantify the curvature and inclination of the lingual surfaces of maxillary anterior teeth.
• To determine the relationship between these morphological features and centric occlusion contacts.

Main Methods:

• Measurements of lingual surface curvature using radius gauges on 32 sets of dental casts (768 measurements).
• Recording the inclination of lingual surfaces relative to the occlusal plane.
• Assessing centric occlusion contact points between maxillary and mandibular anterior teeth.

Main Results:

• Significant differences in curvature were observed between different areas and types of maxillary anterior teeth.
• Average lingual surface inclination was 46 degrees; average radii varied from 5.3 mm (central incisor fossa) to 20.5 mm (canine mesial ridge).
• 97% of canines and 59% of incisors contacted opposing teeth, typically 2.8 mm incisal to the cingulum transition point.

Conclusions:

• Maxillary incisors and canines exhibit distinct functional and curvature characteristics.
• Excessive lingual contouring of maxillary incisors to achieve greater occlusal contact is anatomically abnormal and potentially detrimental.