Cone-beam computed tomography evaluation of bone density of midpalatal suture before, after, and during retention of rapid maxillary expansion in growing patients

Abstract

Objective: To analyze changes in bone density of the midpalatal suture after rapid palatal expansion (RME) with the Hyrax-type expander in growing subjects using cone-beam computed tomography (CBCT). Materials: Fourteen patients (nine girls and five boys; mean age, 11.7 AE 2.4 years) who required RME as part of their orthodontic treatment and had preexpansion (T0) and postexpansion (at the end of active expansion [T1], after a retention period of 3 months [T2], and after 6-month [T3] retention period) CBCT scans. On the axial CBCT images, four regions of interest in the midpalatal suture were analyzed. Bone density (BD) was measured in voxel gray-scale histogram. BD measurements were compared by using Friedman ANOVA with post hoc tests. A P value less than 0.05 was considered statistically significant. Results: BD values in all regions of interest in the midpalatal suture decreased significantly after active expansion (T0-T1) and significantly increased during the retention periods (T1-T2 and T1-T3). According to the density values 3 months after expansion (T0-T2), the remineralization was incomplete. At 6 months of the retention, nonsignificant differences in BD were observed in comparison with the pretreatment values (T0-T3). Conclusions: Active phase of RME produced effective opening of the midpalatal suture with significant decreases in BD levels. The results revealed that are necessary more than 3 months for complete sutural recovery after RME, thus indicating in prepubertal patients, the recommendation to extend the retention time to 6 months to achieve the midpalatal suture remineralization.

Evaluating mandibular symphysis bone density according to various skeletal patterns with CBCT

“…A few studies 12,22 have actually found a linear relationship between CBCT and MDCT measurements by multiplying the CBCT value by 0.7 to get the MDCT value. While absolute BD values cannot be accurately determined using CBCT, trends can be identified by using relative BD values 13,23 . Due to this discrepancy, the measurement of mandibular symphysis BD values is used as relative values and not absolute values.…”

“…When Kim et al 11 investigated the condylar head BD, they found higher BD in the condylar head for TA B L E 1 Mandibular symphysis bone density according to gender and skeletal pattern (HU) The symphysis BD was higher in females than males which were consistent with some previous studies 11,15 absolute BD values cannot be accurately determined using CBCT, trends can be identified by using relative BD values. 13,23 Due to this discrepancy, the measurement of mandibular symphysis BD values is used as relative values and not absolute values. CBCT is becoming increasingly more popular in orthodontics because the amount of radiation exposure to patients can be less than with a traditional panorex and cephalogram under certain conditions.…”

“…Qu et al 10 found a reduced bony support for mandibular incisor correlated with vertical growth. Several studies [11][12][13][14][15] have used CBCT to investigate bone density (BD) for various reasons, but there are few studies on the relationship between the BD and facial type in adult patients.…”

Is There a Difference in Mid-Palatal Suture Density after Rapid Maxillary Expansion, Surgically Assisted Rapid Maxillary Expansion, and Miniscrew-Assisted Rapid Palatal Expansion? A Systematic Review and Meta-Analysis

“…The descriptive data of the ten included studies are summarized in Table 3, in wh it is possible to observe that half of the studies were retrospective [23][24][25][26][27] and the ot…”

“…The descriptive data of the ten included studies are summarized in Table 3, in which it is possible to observe that half of the studies were retrospective [23][24][25][26][27] and the other half were prospective [13,15,16,28,29]. A total of 215 patients were included: 158 females and 57 males.…”