Zafar Qayyum, Umer Khitab.
Assessment of Normal Mouth opening in Adults.
Pak Oral Dental J Jan ;22(2):147-8.

The maximum mouth openings of 680 healthy adults from NWFP–Pakistan of 18 to 70 years old, were measured. For men the mean value and range of maximal mouth opening was 51.97mm (36.38 to 61.23mm) and for women mean value was 47.86mm (35.84 to 59.76mm). The results were similar to those reported by international investigators (Carlson, Land Twing, Lysell, Coxse) in other countries.

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