Establishing a Standard Transverse Maxillary Dimension on Study Casts Using the Intermolar-to-Intercanine Width...

Area of Science:

• Orthodontics
• Dental Anthropology
• Forensic Odontology

Background:

• Maxillary width evaluation is crucial for diagnosing developmental abnormalities and planning orthodontic treatment.
• Limited research exists on transverse maxillary growth due to a lack of standardized diagnostic criteria.
• This study addresses these gaps by defining normal transverse maxillary dimensions.

Purpose of the Study:

• To establish a standard transverse maxillary dimension using the intermolar (IMW) to intercanine (ICW) width ratio.
• To determine this ratio in a large, homogeneous sample of Indian dental Class I well-aligned arches.
• To compare these parameters for sex-based differences.

Main Methods:

• A pan-India, cross-sectional study of 1575 maxillary arch models with normal occlusion.
• Measurement of intermolar (IMW) and intercanine (ICW) linear dimensions and their ratio.
• Statistical analysis and comparison of parameters between sexes.

Main Results:

• The mean intermolar width (IMW) was 36.87mm and intercanine width (ICW) was 35.44mm.
• The mean IMW to ICW ratio was 1.04.
• Males exhibited significantly higher mean IMW and ICW values compared to females.

Conclusions:

• A standard IMW to ICW ratio of 1.04:1 exists in normal, well-aligned dentition.
• This ratio offers a simple chairside method for visually assessing normal maxillary arches.
• The findings have implications for orthodontic diagnosis, forensic odontology, and anthropological studies.