The association of tongue posture with the dentoalveolar maxillary and mandibular morphology in Class III malocclusion: a controlled study

Abstract

The aim of the present study was to evaluate the association of tongue posture with the dentoalveolar maxillary and mandibular morphology in a group of Class III subjects in comparison to a group of Class I subjects. Twenty Class III subjects (9 males, 11 females, 19.2 ± 4.6 years) and 20 Class I subjects (6 males, 14 females, 17.4 ± 1.7 years) were included in the present study. Maxillary and mandibular morphology was defined by the intermolar and intercanine distances, at both the cusps and gingival levels, and by measuring surface area and volume of the palatal vault and mouth floor assessed on three-dimensional digital models. Tongue-to-palate distances were measured on lateral cephalograms. The groups were compared using the Mann-Whitney U-test and correlations between each morphological parameter and the tongue-to-palate distances were calculated using the Spearman correlation coefficient. The mandibular intermolar width at the gingival level was significantly greater in the Class III group (P < 0.01), while the maxillary intercanine widths were significantly smaller in the Class III group (P < 0.05). The mouth floor area and volume and the respective ratios between the mouth floor and palate were significantly greater in the Class III group (P = 0.01). The tongue-to-palate distances were generally greater, i.e. lower tongue posture, for the Class III subjects. Significant correlations were seen between tongue-to-palate distances in the posterior region with the area ratio (rho = 0.44, P < 0.05). Tongue posture is significantly lower in Class III subjects and is associated with the dentoalveolar characteristics of the maxilla and mandible.

Rugoscopy: A Diagnostic Appurtenance for Malocclusion or just a Forensic Aid? - A Pilot Study

“…In Class II malocclusion groups, contact of anterior portion of the tongue with rugae area of hard palate has been shown to be decreased as compared to the control group [28]. While in Class III malocclusion, tongue-to-palate distances were found to be generally greater and tongue posture lower as compared to controls [27]. Although our study has shown differences in pattern in Class I and Class III casts displaying a forking-diverging type on left side, but it was statistically not significant.…”

“…The association of food and taste receptors in the dorsal surface of tongue has been considered responsible for particular configurations and prominence of rugae [3]. And as tongue posture is variant in Class II and Class III patients, it was expected to influence the PR pattern in different categories of malocclusion [27]. In Class II malocclusion groups, contact of anterior portion of the tongue with rugae area of hard palate has been shown to be decreased as compared to the control group [28].…”

Relationship between tongue pressure and maxillofacial morphology in Japanese children based on skeletal classification

“…Palatal volume (PV) was measured using a maxillary dentition model, as described previously . Dental casts were measured using a non‐contact, 3D shape‐measuring device (Vivid 910; Konica Minolta, Tokyo, Japan).…”

Influence of Myofunctional Therapy on Upper Intercanine Distance

“…Furthermore, it is shown, that a correlation between a lower rest posture of the tongue, as in Class III patients, and a small upper intercanine width, exists [24]. An inverted rest posture of the tongue, resting on the palate, should therefore, contribute to a wider maxillary intercanine width [25].…”