Three-dimensional assessment of palatal change in a controlled study of unilateral posterior crossbite correction in the primary dentition

Abstract

The aim of this study was to quantify the palatal change in three groups of children: children with a unilateral posterior crossbite (TCB) who were treated, children with untreated unilateral posterior crossbite (UCB), and children without a crossbite (NCB). Study casts of 60 Caucasian children in the primary dentition (20 TCB, 20 UCB, and 20 NCB), aged 5.4 ± 0.7 years, were collected at baseline (T1) and at 1-year follow-up (T2). Both TCB and UCB groups had unilateral posterior crossbite and midline deviation. The TCB group was treated using a cemented acrylic splint expander in the upper arch. The study casts were scanned using a laser scanner and palatal surface area, palatal volume, and symmetry of the palatal vault were evaluated and compared between the three groups. At T1, the palatal volume of TCB (2698 mm(3)) and UCB (2585 mm(3)) was significantly smaller than that of NCB (3006 mm(3); P < 0.05, analysis of variance test). After treatment, the palatal volume of the TCB group (3087 mm(3)) increased and did not differ from the NCB group (3208 mm(3)), whereas the UCB (2644 mm(3)) had a significantly smaller palatal volume than the NCB or TCB groups (P < 0.05). The increase of palatal volume in the TCB group (389 mm(3)) was significantly greater than in the UCB (59 mm(3)) and NCB (202 mm(3)) groups. The symmetry of the palatal vault was greater than 90 per cent in all three groups at T1 and at T2. Treatment of unilateral posterior crossbite in the primary dentition has a significant effect, particularly on the palatal volume increase.

Evaluation of maxillary arch dimensions and palatal morphology in mouth-breathing children by using digital dental casts

“…The current study showed that in mouth-breathing subjects also the transverse widths measured on the gingival plane were smaller when compared with the control group. As reported by Primozic et al [12,13], measurements on digital dental casts at the level of the gingival plane allow a more accurate analysis of the transverse dimension of maxillary arch because this method of evaluation exclude bias due to improper teeth position as buccal tipping. In the present study a constriction of the maxillary arch was observed with an increasing gradient from the posterior part of the palate at the level of the first upper molars to the anterior part of the palate at the level of the upper deciduous canines (D3 À4.1 mm in SG vs CG; D4 À5.0 mm in SG vs CG; D5 À6.4 mm in SG vs CG; D6 À6.5 mm in SG vs CG).…”

“…As previously described by [12,13], a gingival plane was constructed by connecting the center of the dento-gingival junction of all teeth (Fig. 2).…”

“…However, changes measured with a traditional measuring approaches might not always highlight the modification in the arch form [9,10] and these methods could not exclude bias in assessing the transverse dimension of the maxillary arch due to improper tooth position, such as the buccal tooth tipping [11,12]. To overcome these problems, an optical scanner can be used to obtain three-dimensional images of dental casts [13]. In fact, recent advances in digital technology have vastly improved the diagnostic phase of orthodontic treatment, and analog records have quickly been replaced by digital formats [14].…”

Palatal volume and area assessment on digital casts generated from cone-beam computed tomography scans

“…2,19 In one method, the palatal space selection was based on delimited surfaces. [3][4][5]18,20 A gingival plane was defined connecting the midpoints of the dentogingival junctions. A distal plane was created through the two distal points of the second molars perpendicular to the gingival plane.…”

“…2 Also, they can be used to show the relationship between anomalies in palatal morphology and function such as mouth breathing 3 and posterior crossbite. 4 In addition, they can be used for longitudinal evaluation of palatal vault anatomy. 5 They usually require the use of dental casts, which are an integral part of orthodontic practice and research.…”