This retrospective observational study was conducted using the CBCT records of patients who visited the Department of Orthodontics between January 2014 and July 2024. Institutional ethical committee approval was obtained before starting the study, which was conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidelines and principles of the Declaration of Helsinki. The requirement for written informed consent was waived because of the retrospective design of the study. All patient data were anonymized to ensure confidentiality.

Sample size analysis was performed using the G∗ Power software (version 3.6.9; Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany). This study included 114 participants (equally distributed by sex). The estimated sample size was obtained at 95% power and 5% alpha error with an effect size of 0.59, as presented by the mean difference of 133.5 Hounsfield units (HU) and the pooled standard deviation (SD) of 225.1 in BD of anterior and posterior palate in the reference study.

A total of 820 records were screened for eligibility, and a comprehensive review was conducted on 114 pretreatment CBCT records of the maxilla, which were acquired for the purposes of diagnosing and formulating treatment plans for conditions such as impacted, transposed, or supernumerary teeth, constricted maxilla, miniscrews placement, or any other clinical interventions wherein traditional 2-dimensional radiographic techniques were inadequate to provide sufficient diagnostic information. The patients were categorized into 4 chronological age cohorts (aged 10-13, 14-17, 18-21, and 22-25 years), with each cohort comprising an equal number of males and females. Stratified sampling was used, wherein the dataset was initially partitioned into age-based strata and subsequently further stratified by sex within each age cohort. From each age-gender stratum, an equal number of male and female records were selected using simple random sampling. Only patients with comprehensive CBCT documentation and demographic information were included, and incomplete or duplicated records were omitted. This methodology ensured an equitable representation of age and sex across the cohorts. Patients with cleft palate, craniofacial syndromes, pathologies affecting the sutural area, orthognathic surgery, previous orthodontic treatment, or image artifacts were excluded.

CBCTs were acquired with a CBCT machine (Carestream Dental, Atlanta, Georgia) at 90 kV, with a mean exposure time of 6.4 seconds at 8 mA, voxel size of 0.3 mm, field of view measuring 10 × 10 cm, and slice thickness of 400 μm. The image reconstruction process for visual analysis was executed using CS imaging software (version 8, CS Imaging Software; Carestream Dental, Atlanta, Georgia). The anterior nasal spine (ANS; characterized as the most anterior point of the premaxilla along the midsagittal plane) and posterior nasal spine (PNS; characterized as the most posterior point of the palatine bones along the midsagittal plane) were delineated. CBCT images were standardized by orienting each volumetric dataset such that the coronal slice was positioned to align with the posterior transverse suture, the sagittal slice was positioned to align with the ANS-PNS, and the axial slice was oriented in correspondence with the hard palate and ANS-PNS. The section within the thickness of the hard palate was delineated, and the maturation of the MPS, along with BD, was assessed using CBCT software.

The MPS maturation stage was evaluated according to Angelieri et al, who classified MPS into 5 stages (stages A-E) based on CBCT images ( Fig 1 , A ). However, during the evaluation, some intermediate stages were identified, including B/C, C/D, and D/E. In such instances, a more mature stage was considered. In the sagittal plane, a midsagittal cross-sectional slice was employed to delineate the horizontal axis that intersects the midpoint of the superoinferior dimension of the hard palate (extending from the nasal to the oral surfaces). Subsequently, most axial central cross-sectional slices were used for suture assessment. For reliable and reproducible measurements, it was ensured that all 3 planes were properly oriented.

CBCT measurements: A, MPS maturation assessment, showing stages A-E based on suture appearance, as classified by Angelieri et al ; B, Maxillary transverse dimensions, measured as IMW (distance between buccal cementoenamel junctions of first molars) and ICW (distance between buccal cementoenamel junctions of canines).

Transverse dimensions of the maxilla were measured at 2 regions: intermolar width (IMW) and intercanine width (ICW), as the distance between the buccal cementoenamel junction of the first molars and canines, respectively ( Fig 1 , B ). In the sagittal plane corresponding to the ANS-PNS orientation (midsagittal plane), the maxillary area was systematically segmented into 3 uniform sections (M1, M2, and M3), whereas the palatal area was methodically divided into 2 equivalent sections (P1 and P2) ( Fig 2 , A ) . Subsequently, in the coronal plane aligned with the posterior transverse suture and intersecting the centroid of each segment, the MPS BD was quantitatively evaluated using a rectangular region of interest (ROI) defined by a width of 3 mm, which encompassed the complete vertical extent of the MPS (cancellous bone located between the superior and inferior cortical layers) ( Fig 2 , B-F ). However, in some instances, the ROI unavoidably included portions of the denser nasal crest because of its proximity to the suture, particularly in the anterior segments (M1 and M2). The vertical boundaries of the ROI were set to extend from the nasal surface to the oral surface of the hard palate, as delineated in the midsagittal plane aligned with the ANS and PNS. The measured gray density values as gray value in CBCT were converted to those of HU in computed tomography (CT) by multiplying the gray values of CBCT by 0.7.

BD measurement along the MPS using CBCT: A, Sagittal view showing the MPS divided into 3 maxillary regions (M1, M2, and M3) and 2 palatal regions (P1, P2) for BD assessment; B-F, Coronal views illustrating BD measurement in each region (M1, M2, M3, P1, and P2) using a 3 mm-wide rectangular ROI, capturing the suture’s density to evaluate maturation.

Both evaluators (S.G. and J.K.) were calibrated by allowing both evaluators to analyze and perform CBCT test measurements and provide feedback on technique and accuracy. Consequently, they undertook an evaluation of 10 CBCT scans that were not pertinent to the study for independent appraisal. The same measurements were repeated on separate occasions by the same evaluator to check the reliability over time. The weighted Cohen’s kappa values for the MPS ossification stage were 0.82 for an interobserver reliability and 0.85 for an intraobserver reliability. For BD, ICW, and IMW, the intraclass correlation coefficient (ICC) was used to assess the intraobserver and interobserver reliability. The interobserver reliability values for BD, ICW, and IMW were 0.83, 0.90, and 0.89, respectively. The intraobserver reliability values were 0.85 for BD, 0.92 for ICW, and 0.90 for IMW, showing high reliability.

All measurements were then conducted by 2 calibrated evaluators (S.G. and J.K.) who were provided with coded CBCT scans and blinded to each other’s scores. The images were anonymized, and the evaluators were unaware of the patients’ age and sex. After a washout duration of approximately 1 month, the analysis was repeated on a sample of 30 randomly selected CBCT scans. The statistician who performed the statistical analysis was blinded to the group allocation.

The intraobserver reliability exhibited an excellent reproducibility (weighted kappa = 0.92) for assessment of MPS maturation stage, ICC value of 0.94 for ICW and IMW measurements, and 0.86 for BD measurements. The interobserver reliabilities showed a kappa value of 0.90 for the MPS maturation stage, ICC of 0.92 for ICW and IMW, and ICC values of 0.84 for BD measurements, which showed excellent reliability of the measurements.

The following results address the hypotheses that MPS maturation stages correlate with BD and maxillary transverse dimensions (IMW and ICW), and that BD and IMW serve as quantitative predictors of MPS maturation. On the basis of PCA, the BD at P1 had the highest loading value of 0.991, followed by M3 and P2. The F1 score captured a high percentage (>90%) and, therefore, was used reasonably as a single representative value ( Fig 3 , A ). F1 scores were then extracted for each sample and converted to synthetic BD values using the formula mentioned in the statistical analysis ( Fig 3 , B ). The mean chronological age of 57 males in the study sample was 17.75 ± 4.16 years, whereas for 57 females, it was 17.36 ± 3.99 years, with no statistical significance ( P >0.05). The mean IMW and ICW were statistically greater in females than in males ( P <0.05) ( Table I ).

PCA for BD assessment: A, Bar chart showing the contribution (loading values) of BD measurements from 5 MPS regions (M1, M2, M3, P1, and P2), with P1 contributing most to overall density variation; B, Graph of the F1, which summarized >90% of BD variation, used to create a single gray score for each patient, representing overall suture density for MPS maturation prediction.

Table II shows that statistically significant differences existed in the presence of the MPS maturation stage at different chronological ages in both sexes. In males, the highest percentage was observed in stage C (35.08%), with a significant P value of 0.001, indicating a relationship between age and the MPS stage. In subjects aged 10-13 years, all males were in stages B and C of the MPS maturation stage, whereas 9 females were in stages B and C, and 5 females were in stages D and E. In subjects aged 14-17 years, most of the males were in stage B and none were in stage E, whereas 5 females were in stage E. In subjects aged 18-21 years, 7 (12.28 %) males were in stage C, 5 (8.77 %) in stage D, and 2 (3.50 %) in stage E, whereas 3 (5.26 %) females were in stage C, 4 (7.01 %) in stage D, and 7 (12.28 %) in stage E. Finally, in subjects aged 21-25 years, both males and females were mostly in stage E. This finding suggests that MPS maturation occurs earlier in girls than in boys.

Table II

Distribution of males and females across different MPS stages

MPS stage		Age group (y)				P value †
	Total	10-13	14-17	18-21	22-25
Male
B	13 (22.80)	9 (15.78)	4 (7.01)	0 (0.00)	0 (0.00)	0.001 ∗
C	20 (35.08)	5 (8.77)	8 (14.03)	7 (12.28)	0 (0.00)
D	13 (22.80)	0 (0.00)	4 (7.01)	5 (8.77)	4 (7.01)
E	11 (19.29)	0 (0.00)	0 (0.00)	2 (3.50)	9 (15.78)
Female
B	10 (17.54)	6 (10.52)	4 (7.01)	0 (0.00)	0 (0.00)	0.020 ∗
C	10 (17.54)	3 (5.26)	4 (7.01)	3 (5.26)	0 (0.00)
D	14 (24.56)	3 (5.26)	3 (5.26)	4 (7.01)	4 (7.01)
E	23 (40.35)	2 (3.50)	5 (8.77)	7 (12.28)	9 (15.78)

Only gold members can continue reading. Log In or Register to continue

Share this:

• X
• Facebook

Related

Related posts:

1. Is apex position a determining factor in the orthodontic traction duration of unilateral impacted maxillary canines? A cone-beam computed tomography–based 3-dimensional study
2. The effect of clear aligners with posterior occlusal attachments on daytime masticatory muscle activity
3. Quality assessment of ultra low dose-low dose orthopantomograms reconstructed from CBCT for orthodontic purposes
4. The effects of treatment in Class II correction: A comparison between the Carriere Motion 3D appliance and a simple alternative

Stay updated, free articles. Join our Telegram channel

Join