Midpalatal suture morphology and bone density evaluation after orthodontic expansion: a cone-bean computed tomography study in correlation with aesthetic parameters

Rom J Morphol Embryol. 2018;59(3):803-809.

Abstract

Maxillary expansion is one of the earliest methods of obtaining space used in the field of orthodontics. Maturing craniofacial sutures along with the increase in bone density and rigidity are main causes of high resistance of the maxilla to transversal expansion forces applied to the midpalatal suture through orthodontic appliances. Fifty-three patients, with a mean age of 16.4 years and a diagnosed transverse plane orthodontic anomaly were included in this study and divided in two groups: male group and female group. Cone-beam computed tomography (CBCT) was used for measurements conducted in order to determine bone density before and after jaw expansion in different segments of the midpalatal suture: anterior, middle and posterior. In males, slightly higher bone density values were observed in the midpalatal suture than in females before and after maxillary expansion, with average values ranging from 128.5 Hounsfield units (HU) to 672.9 HU. Bone density along the maxillary suture plays an important role in the success rate of orthodontic treatment. Assessing the palatal suture maturation on CBCT images is a very promising predictor for conventional or surgically assisted jaw expansion. Intra and extraoral pictures were used to evaluate the position of the zenith in the aesthetic area and gingival aesthetic line (GAL) class. In the study, there was a significant reduction in the number of class II, class III and class IV and an implicit increase of GAL I class that ensure a pleasant transition of the gingival level between the anterior maxillary teeth. The distribution of the gingival height in terms of the classes found prior to the orthodontic treatment remained unchanged after treatment.

MeSH terms

  • Adolescent
  • Bone Density / physiology*
  • Cone-Beam Computed Tomography*
  • Esthetics*
  • Female
  • Gingiva / surgery
  • Humans
  • Imaging, Three-Dimensional
  • Male
  • Palatal Expansion Technique*
  • Sutures*