Evaluation of tongue and mandibular volumes of skeletal class i and class iii individuals by using cone beam computed tomography

The relationship between craniofacial skeletal growth and oral soft tissues, especially tongue, has been discussed in the scientific literature for years. The aim of our study is to determine whether there is a correlation between tongue and mandibular volume in skeletal Class I and Class III patients; if present, to correlate with the type of malocclusion; to assess tongue / mandible volume ratios within the groups themselves and volume differences between the sexes with cone-beam computed tomography (CBCT) and to contribute to the diagnosis and treatment planning of orthodontists and surgeons. The CBCT data of skeletal Class I control group (average age 20,9) in our study were composed from 27 individuals (16 female, 11 male) and skeletal Class III group (average age 22,5) was composed from 23 individuals (13 female, 10 male). The tongue and mandible volumes were measured on the identified CBCT images which were retrospectively selected. Volumetric measurements were performed using a three dimensional tomography modelling program, Mimics® 17.0 (Materialise, Leuven, Belgium). When the results of our study were evaluated, no statistically significant difference was observed between male and female average mandibular volumes in the skeletal Class III group; but the average tongue volume of men was found to be higher than the women. In the control group, the average mandibular volume of men wasfound higher than females; no statistically significant difference was observed between the mean of tongue volume. There was no statistically significant difference between the mean tongue/mandible volume ratio of males and females within the groups themselves. When the data was evaluated between groups, the mean volume of the mandible of the skeletal Class III group was found to be lower than the skeletal Class I group; but there was no statistically significant difference between average tongue volumes. The mean tongue/mandible volume ratio of the skeletal Class III group was found to be statistically significantly higher than the control group mean. When the results of the study are evaluated, it is seen that the increased tongue volume and the mandibular volume are not related. Key words: Mandibular volume, tongue volume, CBCT