Prediction of rapid palatal expansion success via fractal analysis in hand-wrist radiographs

Evaluation of mandibular trabecular bone structure in growing children with Class I, II, and III malocclusions using fractal analysis: A retrospective study

OBJECTIVE

The present study aimed to evaluate the mandibular bone structure of patients with different malocclusions by using fractal dimension (FD) analysis on dental panoramic radiographic images.

MATERIAL AND METHODS

Pre-treatment panoramic radiographic images of 103 patients were included in the study and divided into 3 groups as Class I (group 1: 0

RESULTS

FD values were lower in Class I sagittal skeletal pattern than Class II and III groups in anterior ROI FD, premolar ROI FD, angulus ROI FD, and mean FD values. There were differences between Class I and Class III skeletal patterns (P=0.023 for anterior ROI FD, P=0.016 for premolar ROI FD, P=0.034 for angulus ROI FD, and P=0.014 for mean FD). Class I and II malocclusions differed in anterior ROI FD (P=0.029) and also Classes II and III showed differences in angulus ROI FD (P=0.029).

CONCLUSION

Sagittal skeletal patterns may result in differences in the structure of the mandibular trabecular bone.

Collapse

Key Words

• Fractal dimension analysis
• Orthodontics
• Panoramic radiography
• Sagittal skeletal malocclusions

Collapse

MESH Headings

• Humans
• Child
• Mandible/diagnostic imaging
• Male
• Female
• Fractals
• Retrospective Studies
• Radiography, Panoramic
• Malocclusion, Angle Class III/diagnostic imaging
• Malocclusion, Angle Class II/diagnostic imaging
• Cancellous Bone/diagnostic imaging
• Malocclusion, Angle Class I/diagnostic imaging
• Malocclusion/diagnostic imaging
• Adolescent
• Cephalometry/methods

Collapse

Grants Collapse

Affiliation(s)

Hümeyra Tercanlı Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Akdeniz University, 07058 Antalya, Turkey
Esra Bolat Gümüş Department of Orthodontics, Faculty of Dentistry, Akdeniz University, 07058 Antalya, Turkey.

Collapse

Determination of growth and developmental stages in hand-wrist radiographs : Can fractal analysis in combination with artificial intelligence be used?

PURPOSE

The goal of this work was to assess the classification of maturation stage using artificial intelligence (AI) classifiers.

METHODS

Hand-wrist radiographs (HWRs) from 1067 individuals aged between 7 and 18 years were included. Fifteen regions of interest were selected for fractal dimension (FD) analysis. Five predictive models with different inputs were created (model 1: only FD; model 2: FD and Chapman sesamoid stage; model 3: FD, age, and sex; model 4: FD, Chapman sesamoid stage, age, and sex; model 5: Chapman sesamoid stage, age, and sex). The target diagnoses were accelerating growth velocity, very high growth velocity, and decreasing growth velocity. Four AI algorithms were applied: multilayer perceptron (MLP), support vector machine (SVM), gradient boosting machine (GBM) and C 5.0 decision tree classifier.

RESULTS

All AI algorithms except for C 5.0 yielded similar overall predictive accuracies for the five models. In order from lowest to highest, the predictive accuracies of the models were as follows: model 1 < model 3 < model 2 < model 5 < model 4. The highest overall F1 score, which was used instead of accuracy especially for models with unbalanced data, was obtained for models 1, 2, and 3 based on SVM, for model 4 based on MLP, and for model 5 based on C 5.0. Adding Chapman sesamoid stage, chronologic age, and sex as additional inputs to the FD values significantly increased the F1 score.

CONCLUSION

Applying FD analysis to HWRs is not sufficient to predict maturation stage in growing patients but can be considered a growth rate prediction method if combined with the Chapman sesamoid stage, age, and sex.

The effect of mentoplate application on the condyle

BACKGROUND

The aim of the study was to investigate the changes occurring in the mandibular condyle by using mentoplate together with rapid maxillary expansion (MP-RME) treatment in the correction of skeletal class III relationship, using fractal analysis (FA).

METHODS

The sample consisted of 30 individuals (8-11 years) diagnosed with skeletal Class III malocclusion who underwent MP-RME treatment. Archival records provided cone-beam computed tomography (CBCT) images taken at two intervals: before MP-RME treatment (T0) and after treatment (T1). The CBCT images were obtained using standardized settings to ensure consistency in image quality and resolution. The trabecular structures in the bilateral condyles at both T0 and T1 were analyzed using FA. The FA was performed on these condylar images using the Image J software. The region of interest (ROI) was carefully selected in the condyle to avoid overlapping with cortical bone, and the box-counting method was employed to calculate the fractal dimension (FD). Statistical analysis was conducted to compare the FD values between T0 and T1 and to evaluate gender differences. The statistical significance was determined using paired t-tests for intra-group comparisons and independent t-tests for inter-group comparisons, with a significance level set at p < 0.05.

RESULTS

The analysis revealed no statistically significant differences in the trabecular structures of the condyles between T0 and T1 (p > 0.05). However, a significant gender difference was observed in FA values, with males exhibiting higher FA values in the left condyle compared to females at both T0 and T1 (p < 0.05). Specifically, the FA values in the left condyle increased from a mean of 1.09 ± 0.09 at T0 to 1.13 ± 0.08 at T1 in males, whereas in females, the FA values remained relatively stable with a mean of 1 ± 0.09 at T0 and 1.03 ± 0.11 at T1.

CONCLUSION

The findings indicate that MP-RME therapy does not induce significant alterations in the trabecular structure of the mandibular condyle. These results suggest the treatment's safety concerning the structural integrity of the condyle, although the observed gender differences in FA values warrant further investigation.

Evaluation´ of mandibular alveolar bone in patients with different vertical facial patterns : A cross-sectional CBCT study

PURPOSE

The study aimed to investigate the morphological and structural differences of mandibular alveolar bone between different vertical facial patterns (VFP).

METHODS

In all, 66 CBCT scans of patients were selected for the study: 24 were designated as hyperdivergent, 25 as normodivergent, and 17 as hypodivergent. Fractal values of the interdental alveolus were measured at the incisor, canine, premolar, and molar regions. The minimum trabecular bone width (MTBW) of the alveolus, the buccal and lingual cortical bone thicknesses, and the total alveolar width (AW) at the minimum trabecular bone level were measured. One-way analysis of variance and Tukey test were used to compare the groups. The correlations between FMA (Frankfurt mandibular plane angle) and other measurements were analyzed by Pearson analysis.

RESULTS

No significant differences were detected in fractal values and buccal and lingual cortical bone thicknesses between the groups. The MTBW and AW of the hypodivergent individuals were found to be higher in the anterior and premolar interdental sites. FMA was found to be significantly correlated with MTBW and AW.

CONCLUSIONS

The patients with different VFPs did not exhibit significant differences in the trabecular complexity of the mandibular alveolus. Hypodivergent patients tend to have thicker trabecular and alveolar bone widths than normodivergent and hyperdivergent individuals.

Assessment of mandibular trabecular structure and cervical vertebral maturation using fractal analysis

BACKGROUND

Changes in bone trabeculae occur during skeletal maturation. Fractal analysis is a technique for assessing changes in the internal structure of the bone.

OBJECTIVE

The aim of this study was to investigate correlation of bone trabeculation measured on panoramic and lateral cephalometric radiographs with cervical vertebral maturation stages (CVMS).

METHODS

CVMS was evaluated on lateral cephalometric radiographs of 120 individuals aged 6 to 18 years. The subjects were divided into 6 groups (n= 20 each) according to CVMS. On panoramic and lateral cephalometric radiographs, fractal dimension (FD) analyses were performed in mandibular corpus, gonial and condylar regions and cervical vertebral bodies (C2, C3, C4).

RESULTS

FD measurements from the mandibular corpus region bilaterally and C2-C4 vertebral bodies showed significant positive correlations with CVMS (r= 0.418, r= 0.412, r= 0.324, r= 0.304, r= 0.263, respectively). Significant differences were found in the FD values of the right/left mandibular corpus and C2 and C3 vertebrae compared to CVMS (P< 0.001, P< 0.001, P= 0.005, P= 0.019, respectively).

CONCLUSION

Significant positive moderate correlations between the FD values of the right and left mandibular corpus and CVMS suggest that fractal analysis may be useful in determining skeletal maturity stage. The significant FD values obtained from the right/left mandibular corpus, and C2 and C3 vertebra indicate that the complexity of the internal trabecular structure increases with maturation.

Assessment of correlation between hand-wrist maturation and cervical vertebral maturation: a fractal analysis study

BACKGROUND

To investigate whether fractal dimension (FD) measurements from hand-wrist radiographs and lateral cephalometric radiographs are correlated with each other and with skeletal maturation stages.

METHODS

In this retrospective study conducted on hand-wrist and lateral cephalometric radiographs obtained from patients between 2017 and 2023, hand-wrist maturation stages (HWMS) and cervical vertebral maturation stages (CVMS) of 144 subjects (6 to 17 years of age) were assessed radiographically. The participants were divided into nine groups (n = 16 each) based on HWMS. Fractal analysis was performed on the radiographs of the radius, the middle finger phalanges (proximal, medial and distal), and the cervical vertebral bodies (C2, C3, C4). Mean and standard deviation values, Spearman's and Pearson correlation analyses, one-way ANOVA, Kruskal-Wallis H tests and Mann-Whitney-U test were used to evaluate the data.

RESULTS

Positive correlations were found between the FD values of the radius and HWMS or CVMS (r = .559, P = .001, r = .528 P = .001 respectively). The FD values of the radius were positively correlated with those of all cervical vertebrae (C2, C3, C4), proximal and medial phalanges as well as age. FD values measured from the proximal phalanx, medial phalanx and radius showed significant differences among both HWMS and CVMS (P < .05). HWMS was strongly correlated with CVMS (r = .929, P = .001). Age was strongly correlated with HWMS (r = .795, P = .001) and CVMS (r = .756, P = .001). There was a significant difference in terms of age distribution among HWMS and CVMS (P < .05).

CONCLUSIONS

FD measurements on hand-wrist radiographs can provide useful information for the assessment of skeletal maturation stage. Especially, FD measurements from the radius are important and more reliable to predict skeletal maturation stage.

Evaluation of trabecular changes following advancement genioplasty combined with or without bilateral sagittal split osteotomy by fractal analysis: a retrospective cohort study

BACKGROUND

It is aimed to investigate whether there was a difference in radiographic changes in the operational areas between genioplasty alone and genioplasty combined with mandibular advancement and to evaluate the fractal dimension (FD) to assess trabecular changes after genioplasty surgery.

METHODS

Preoperative-(T0) and postoperative-(T1) panoramic radiographs of 26 patients without any complications who underwent genioplasty combined with bilateral sagittal osteotomy and mandibular advancement or genioplasty alone were selected. In the panoramic radiographs of both groups, the genial segment, mandibular angulus, and surgical osteotomy line were examined using FD. The box-counting method was used for FD evaluation.

RESULTS

It was determined that FD values before and after treatment were similar in both groups for all regions where measurements were made. After surgery, the FD values of the middle region of the genial segment were found to be significantly lower than the other regions. At T1, the FD values at the osteotomy area were found to be significantly higher than those in the middle region of the genial segment.

CONCLUSION

Trabecular structure does not differ in patients undergoing genioplasty alone or in combination with mandibular advancement osteotomy. The middle region of the genial segment heals later than other regions.

Comparison of the effects of removable functional appliance therapy applied in pubertal and postpubertal periods: A retrospective cephalometric and fractal analyses study

INTRODUCTION

In this study, we compared the effects of functional treatment with Twin-block appliance on the bony architectures of the maxilla and mandible by fractal dimension (FD) analysis, and the skeletal and dentoalveolar effects by cephalometric analysis, in pubertal and postpubertal patients with Class II malocclusion.

METHODS

This study comprised 60 patients who underwent Twin-block treatment. Group 1 consisted of 30 patients in the pubertal period (6 boys and 24 girls; mean age 12.27 ± 1.35 years), whereas group 2 consisted of 30 patients in the postpubertal period (6 boys and 24 girls; mean age 13.73 ± 1.51 years). FD analysis was performed on the patients before and after Twin-block panoramic and lateral cephalometric radiographs. Cephalometric analysis was also conducted. Paired and Student t tests were used to compare the parametric data, and Wilcoxon signed rank and Mann-Whitney U tests were conducted to compare the nonparametric data.

RESULTS

SNB, Pg-N, N-Me, ANS-Me, IMPA, L1/NB, Co-Gn, Go-Gn, S-Go, Co-Go, and Go-Me significantly increased in both groups after treatment. FD values of tuber, condyle, and molar regions significantly decreased in group 1, whereas no significant differences were observed in group 2 after treatment.

CONCLUSIONS

In the pubertal period, the Twin-block appliance resulted in skeletal correction by causing bone remodeling and reshaping in both jaws along with the dentoalveolar correction. In the postpubertal period, Twin-block had no significant effect on the bone trabecular arrangement in the investigated areas but produced cephalometric improvement to a certain extent with lower skeletal and higher dental impact.

Evaluation of the compatibility of C2, C3, and C4 fractal dimension values with hand-wrist and cervical vertebra maturation methods in determining skeletal maturation

OBJECTIVES

To examine the correlation between the fractal dimension (FD) values of cervical vertebrae (C2, C3, and C4) and hand-wrist maturation (HWM) and cervical vertebra maturation (CVM) methods. In addition, the correlation between the pubertal growth spurt (PGS) and FD values was examined.

METHODS

The lateral cephalometric and hand-wrist radiographs of 120 subjects (61 females and 59 males) aged 8-18 years with a mean age of 13 years, were evaluated retrospectively. The CVM stages were determined in accordance with Hassel-Farman's modification of Lamparski criteria. The HWM stages were determined in accordance with Björk and Grave-Brown criteria. Both HWM and CVM stages were divided into two according to PGS. Fractal analysis of cervical vertebrae was performed according to the White-Rudolph method. The relationships between HWM stages, CVM stages and other variables were evaluated by Spearman's rank-order correlation coefficient. The relationships between FD values, chronological age, and divided stages were evaluated by the Pearson correlation coefficient. The Mann-Whitney U test was used to compare the FD values of two divided stages.

RESULTS

There were positive and statistically significant positive correlations between chronological age and both HWM and CVM stages. There was a positive and statistically significant correlation between CVM and HWM stages. In females and total, there were negative and statistically significant correlations between C4 FD values and divided HWM stages, and the differences between C4 FD values of divided HWM stages were also statistically significant. In total, there was a negative and statistically significant correlation between C4 FD values and divided CVM stages, and the difference between C4 FD values of divided CVM stages was also statistically significant.

CONCLUSION

The negative correlations found between C4 FD values and divided HWM and CVM stages suggest the fractal analysis of cervical vertebrae, especially of C4, may be used as an objective tool for evaluating the PGS.

Assessment of the relationship between fractal analysis of mandibular bone and orthodontic treatment duration : A retrospective study

PURPOSE

This retrospective study aimed to determine whether a correlation exists between the fractal dimension value and overall orthodontic treatment duration in children and young adults.

METHODS

The study included a total of 643 patients (age: 10-25 years) who received orthodontic treatment between January 2015 and March 2020. Patient records and pretreatment panoramic radiographs were evaluated. The regions of interest selected for calculating fractal dimension were the bilateral mental foramen regions of the mandible. Fractal dimension was set in relation to orthodontic treatment duration using a linear regression model which was also adjusted for potential confounding variables. Total treatment duration was the outcome variable of interest used as a continuous variable. The predictor variables of interest included age, gender, type of dental and skeletal malocclusion, vertical growth pattern, extraction type, and fractal dimension.

RESULTS

The mean age, treatment duration, and fractal dimension were 14.56 years, 27.01 months, and 1.23 mm, respectively. Multiple linear regression analysis showed that the fractal dimension had a significant influence on overall treatment duration (P < 0.001). From the other variables, Angle class II malocclusion significantly influenced treatment duration (P < 0.01), age showed a significant negative correlation with treatment duration (P < 0.01), and treatment duration significantly increased for patients with tooth extractions (P < 0.001).

CONCLUSION

There was a negative correlation between fractal dimensions at the mandibular mental region and total orthodontic treatment duration. Fractal dimension analysis may help to understand physiologic features of alveolar bone and predict orthodontic tooth movement.

Effects of reverse headgear therapy on mandibular trabecular structure: A fractal analysis study

OBJECTIVES

The aim of this study was to assess the effects of reverse headgear (RHG) treatment combined with rapid maxillary expansion (RME) on the trabecular structure of the mandibula using fractal dimension (FD) analysis.

METHODS

Forty-four individuals with skeletal Class III malocclusion were selected from the archives and divided into two groups as patients who underwent treatment with RME + RHG (RHG-G, 22 patients) and untreated control group (C-G, 22 patients). The before (T0) and after (T1) treatment lateral cephalometric and panoramic radiographs were collected in the RHG-G and in the control group, radiographs obtained with similar time intervals were grouped as T0 and T1. Cephalometric and FD analysis was conducted on T0 and T1 lateral cephalometric and panoramic radiographs. The intragroup comparison of cephalometric and FD data was performed using paired t test and Wilcoxon Signed Ranks test, while independent t test and Mann-Whitney U test were used for intergroup comparison.

RESULTS

C-G had higher FD values in the right mandibular corpus and left mandibular ramus values at T0 (P < .05). The only significant difference in the intragroup comparisons was detected in the FD values of the right mandibular corpus in the C-G (P < .05). No significant differences were found in the FD between the groups in any of the areas measured (P > .05).

CONCLUSIONS

RME + RHG therapy did not cause any significant trabecular changes in the mandibula when compared to the control group.

Three-dimensional palatal morphology and upper arch changes following nonsurgical and surgical maxillary expansion in adults

OBJECTIVE

The objective of this study was to evaluate the effects of nonsurgical rapid maxillary expansion (RME) and surgically assisted RME (SARME) on palatal morphology and upper arch dimensions using three-dimensional (3D) models in skeletally mature patients.

STUDY DESIGN

Thirty-eight skeletally mature patients with a maxillary transverse deficiency were divided into RME and SARME groups. Nineteen patients in the RME group (mean age, 19.16 ± 2.25 years) were treated using a full-coverage bonded acrylic splint expander; 19 patients in the SARME group (mean age, 20.38 ± 3.36) were treated using the banded palatal expansion appliance with hyrax screws. The 3D models were obtained before and after expansion. The maxillary dental arch widths, maxillary first molar angulation, palatal area, and palatal volume were calculated on the 3D models.

RESULTS

All variables showed statistically significant changes after the retention period (P < .001). The maxillary arch width between first premolars (P < .05), the palatal area (P < .01), and the palatal volume (P < .05) significantly increased in the SARME group compared to the RME group. The maxillary first molar tipping in the RME group was significantly higher than that in the SARME group (P < .01).

CONCLUSIONS

Although SARME has more positive effects in skeletally mature patients, nonsurgical RME can be considered as an alternative by evaluating surgical risks, periodontal status, and the need for skeletal expansion.

Evaluation of architectural changes in mandibular trabecular and cortical bone pattern after functional treatment

Purpose:

To assess the changes in mandibular trabecular and cortical bone following functional appliance treatment through fractal dimension (FD) and cortical thickness (CorT) measurements.

Material and methods

The study was performed on 45 mandibular retrognathia cases. While the treatment group (T) comprised 30 patients treated using a functional appliance for one year during puberty, the control group (C) consisted of 15 patients who did not receive any orthodontic treatment due to insufficient oral hygiene. FD and CorT analyses were bilaterally evaluated for each mandible. FD measurements were performed on the condylar process, the antegonial notch, and ramus regions on panoramic radiographs. A paired t-test was applied for group analysis, before (T1) and after treatment (T2) and, correspondingly, before (C1) and after (C2) controls. In addition, an independent t-test was used to determine differences between the treatment (∆T = T2−T1) and the control group (∆C = C2−C1).

Results

Statistically significant differences were found in the treatment group between the initial and post-treatment FD values of the right (p < 0.05) and left condyles (p < 0.05), and the CorT measurements on the right (p < 0.01) and the left sides (p < 0.05). There was no statistically significant difference in FD parameters in the control group and a significant difference was only found in the left CorT (p < 0.05). A comparison of the treatment and control groups revealed that the changes in FD and CorT measurements were not statistically significantly different between the groups (p > 0.05).

Conclusion:

Mandibular protraction appliances do not produce trabecular bone alteration in the mandibular condyles, the antegonial notch and ramus over a 12-month time period.

Evaluation of mandibular morphologic measurements and trabecular structure among subgroups of impacted mandibular third molars

OBJECTIVE

To investigate mandibular morphologic measurements and trabecular structures that may cause mandibular third molar (MM3) impaction according to MM3 subgroups.

METHODS

A total of 150 MM3 of 2175 panoramic radiographs (PRs) were reviewed. MM3s according to Winter (vertical), Pell & Gregory Class 1 and group: A, B, C on PRs were included in the study group. Fractal dimensions (FD) and mandibular morphologic measurements were evaluated. Statistical analysis for parametric values was performed using one-way analysis of variance (ANOVA). Statistical analysis for non-parametric values was performed using the Kruskal-Wallis H test.

RESULTS

Statistically, a significant difference was found only in terms of angle of impaction among the groups of MM3 (p < 0.05) [Winter (vertical), and Pell & Gregory Class 1 and group A, B, C]. There was no difference among groups A, B, C in mandibular morphology and trabecular structure, but group C showed different characteristics than the other groups only in terms of impaction angle.

CONCLUSION

The trabecular structure and morphometric properties except for the angle of impaction do not affect impacted MM3s with adequate retromolar space and vertical angle.