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Clinical measurement of normal maximum mouth opening in children
Youssef S Abou-Atme1, Nada Chedid, Marcello Melis
1Department of Pediatric Dentistry, University of Saint Joseph, Beirut, Lebanon.
Insights
A simple method to assess maximum mouth opening (MMO) in children using three fingers is proposed. While easy to perform, this finger-based measurement is not highly reliable for precise MMO evaluation.
Area of Science:
- Pediatric dentistry
- Anthropometry
- Oral health assessment
Background:
- Accurate assessment of maximum mouth opening (MMO) is crucial in pediatric dentistry.
- Existing methods for MMO assessment may lack simplicity or proportionality to body size.
- Developing a quick, body-size-proportional tool for MMO evaluation in children is needed.
Purpose of the Study:
- To evaluate a simple, body-size-proportional method for assessing maximum mouth opening (MMO) in children.
- To determine the reliability of using finger widths as a proxy for MMO.
- To investigate correlations between MMO, finger measurements, and anthropometric parameters in children.
Main Methods:
- A study involving 102 children recorded maximum mouth opening (MMO), finger widths (three and four fingers), height, weight, and age.
- Subjects attempted to place vertically aligned fingers between the upper and lower central incisors at maximum mouth opening.
- Statistical analysis examined correlations between variables and differences in MMO measurements.
Main Results:
- All children could position three fingers, but only 36.3% could position four fingers between their incisors.
- Maximum mouth opening (MMO) showed significant differences compared to three- and four-finger widths.
- MMO positively correlated with height, weight, and age; no significant gender differences were found.
Conclusions:
- Using three fingers to assess maximum mouth opening (MMO) in children offers a simple, quick evaluation method.
- However, the three-finger method is not a highly reliable measure for precise MMO assessment.
- Anthropometric factors like height, weight, and age are moderately to strongly correlated with finger measurements for MMO evaluation.
Abstract:
This study was designed to find a method of assessing maximum mouth opening (MMO), using a tool that is proportional to the body size. One hundred two (102) children were selected to participate in the study. MMO, the width of three fingers (index, middle and ring fingers), four fingers (index, middle, ring and little fingers), body height, weight and age of each child were recorded, and the ability of each subject to position the fingers, vertically aligned between the upper and lower central incisors with the mouth maximally open, was documented. All subjects were able to position three fingers between the upper and lower central incisors, while only 37 (36.3%) were able to position four fingers. MMO was significantly different from the width of three and four fingers and was positively correlated with both weight and height and with age. Height, weight, and age showed a moderate to strong correlation with all finger measurements; no gender significant difference was observed for MMO. The findings of this study suggest that the ability to position three fingers between the upper and lower incisors with the mouth wide open can be considered a simple method to quickly evaluate MMO, but that it is not highly reliable.
