Prediction of rapid maxillary expansion by assessing the maturation of the midpalatal suture on cone beam CT

Why does maxillary skeletal expansion work with some adults and fail with Others?: A narrative review

Maxillary skeletal expansion is considered a challenging treatment modality in adult ages. Mini-screw-assisted rapid palatal expansion (MARPE) is considered a pioneer in providing a solution for maxillary deficiency in adults away from any surgical interventions. If we consider patient cooperation and motivation, together with operator skills, as constant factors during MARPE, and exclude all hygiene and soft tissue complications that jeopardise the appliance's stability, there is a percentage of expansion failure recorded in different studies with no emphasis on what makes mid-facial diastema appear in some, rather than others. Electronic databases including PubMed, Scopus, Google Scholar, and Web of Science, were searched for literature published in English till 2023. Failure was related in some literature to different criteria, as of yet, no verifiable indicators would allow us to determine success or failure in advance. This review highlighted the most common reasons for failure discussed in different literature: Chronological Age, Mid-palatal suture maturation, Bone density, Sex, Race, Appliance design, and Expansion technique used. This study could be considered an attempt to make candidate selection for non-surgical maxillary skeletal expansion at this old age easier, time-saving, and cost less.

Feasibility of 3 Tesla MRI for the assessment of mid-palatal suture maturation: a retrospective pilot study

The maxilla occupies a key position in dentofacial orthopaedics, since its transversal development can be directly influenced by orthodontic therapy. The maturation stages of the mid-palatal suture, which are obtained from cone-beam computed tomography images (CBCT), present an addition to clinical decision-making in transversal discrepancies of the upper jaw. In an endeavour to reduce ionizing radiation in adolescents and young adults, who are particularly susceptible to long term stochastic irradiation effects, we investigated the feasibility of 3 Tesla (3T) MRI in detecting the maturation stages of the mid-palatal suture. A collective of 30 patients aged 24-93 years with routine neck MRI at 3T, underwent an additional three-dimensional isotropic T1 weighted study sequence of the midface. Image evaluation was performed on axial, multi-planar formatted reconstructions of the dataset aligned to the midline axis of the palate, and curved reconstructions aligned to the concavity of the palate. Inverted images helped to achieve an image impression similar to the well-known CBCT appearance. All datasets were reviewed by three readers and mid-palatal maturation was scored twice according to Angelieri et al. Intra- and inter-rater agreement were evaluated to measure the robustness of the images for clinical evaluation. 3T MRI deemed reliable for the assessment of mid-palatal suture maturation and hence for the appraisal of the hard palate and its adjacent sutures. The data of this pilot study display the feasibility of non-ionizing cross-sectional MRI for the determination of sutural maturation stages. These findings underline the potential of MRI for orthodontic treatment planning, further contributing to the avoidance of unnecessary radiation doses.

Skeletal and Dentoalveolar Changes in Growing Patients Treated with Rapid Maxillary Expansion Measured in 3D Cone-Beam Computed Tomography

The skeletal and dental effects of rapid maxillary expansion (RME) have been extensively studied, but high-quality research is still needed to determine the three-dimensional (3D) effects of RME. The aim of this study was to compare skeletal and dentoalveolar parameters through cone-beam computed tomography (CBCT) pre- (T1) and post-treatment (T2) with respect to RME. Twenty growing patients (mean age 10.7 years) were treated with a Hyrax-type expander. A 3D CBCT was performed at T1 and T2, measuring nasal width, maxillary width, palatal height, maxillary arch perimeter, angulation of the upper first molar, and intermolar width. The mean palatal suture opening was 2.85 ± 0.62 mm (p < 0.0001). Nasal width increased 1.28 ± 0.64 mm and maxillary width 2.79 ± 1.48 mm (p < 0.0001). In contrast, palatal height was reduced 0.65 ± 0.64 mm (p < 0.0001). Regarding arch perimeter, the radicular perimeter increased 2.89 ± 1.80 mm, while the coronal perimeter increased 3.42 ± 2.09 mm (p < 0.0001). Molar angulation increased 5.62 ± 3.20° for the right molar and 4.74 ± 2.22° for the left molar (p < 0.0001). Intermolar width increased 5.21 ± 1.55 mm (p < 0.0001). Treatment with Hyrax produced a significant opening in the mean palatal suture. Also, a significant increase in nasal width, maxillary width, arch perimeter, molar angulation, and intermolar width, and a decrease in palatal height, were observed.

Correlation Between Third Molar Mineralization and Midpalatal Suture Maturity: A Cone Beam Computed Tomography Study

BACKGROUND Midpalatal suture ossification varies in patients of different ages, which can lead to making inaccurate presumptions when considering effective treatment timing based on chronological age. Chronological age provides only general information, whereas dental development correlates with skeletal growth, which suggests that tooth mineralization could be considered to be a precise criterion for determining the midpalatal suture's maturity. The present study was conducted to investigate the association between third-molar mineralization and midpalatal suture's maturation stages using cone-beam computed tomography (CBCT) images. MATERIAL AND METHODS The study involved 97 CBCT images of patients aged 8-37 years with normal growth and development. Subjects with cleft lip and palate, caries treatment, or present cavities in the third molars were not included in the study. The stages of midpalatal suture ossification were evaluated according to the protocol suggested by Angelieri et al, and the third-molar mineralization degree was measured by the Demirjian index. Statistical analysis was performed to evaluate correlations between the variables. RESULTS Patients with advanced third-molar mineralization stages were found to have greater midpalatal suture maturity. A statistically significant positive correlation was found between the stages of third-molar mineralization and midpalatal suture maturation (R=0.814, P<0.01). Third-molar development was also found to be associated with chronological age (R=0.883, P<0.01). CONCLUSIONS A measure of third-molar mineralization does not allow for accurate determination of the midpalatal suture maturation stage.

A novel method for assessment of human midpalatal sutures using CBCT-based geometric morphometrics and complexity scores

INTRODUCTION

Management of dentofacial deficiencies requires knowledge about sutural morphology and complexity. The present study assesses midpalatal sutural morphology based on human cone-beam computed tomography (CBCT) using geometric morphometrics (GMM) and complexity scores. The study is the first to apply a sutural complexity score to human CBCT datasets and demonstrates the potential such a score has to improve objectiveness and comparability when analysing the midpalatal suture.

MATERIALS AND METHODS

CBCTs of various age and sex groups were analysed retrospectively (n = 48). For the geometric morphometric analysis, landmark acquisition and generalised Procrustes superimposition were combined with principal component analysis to detect variability in sutural shape patterns. For complexity analysis, a windowed short-time Fourier transform with a power spectrum density (PSD) calculation was applied to resampled superimposed semi-landmarks.

RESULTS

According to the GMM, younger patients exhibited comparable sutural patterns. With increasing age, the shape variation increased among the samples. The principal components did not sufficiently capture complexity patterns, so an additional methodology was applied to assess characteristics such as sutural interdigitation. According to the complexity analysis, the average PSD complexity score was 1.465 (standard deviation = 0.010). Suture complexity increased with patient age (p < 0.0001), but was not influenced by sex (p = 0.588). The intra-class correlation coefficient exceeded 0.9, indicating intra-rater reliability.

CONCLUSION

Our study demonstrated that GMM applied to human CBCTs can reveal shape variations and allow the comparison of sutural morphologies across samples. We demonstrate that complexity scores can be applied to study human sutures captured in CBCTs and complement GMM for a comprehensive sutural analysis.

Can surgically assisted rapid palatal expansion (SARPE) be recommended over orthodontic rapid palatal expansion (ORPE) for girls above the age of 14? : A cone-beam CT study on midpalatal suture maturation

BACKGROUND

For patients with a maxillary transversal deficiency (MTD), various treatment options are available, partly based on the practitioner's experience. This study aimed to determine a cut-off age for decision making between surgically assisted rapid palatal expansion (SARPE) over orthodontic rapid palatal expansion (ORPE) based on skeletal maturation in a female population.

METHODS

A total of 100 cone beam computed tomography (CBCT) images of young females were analyzed on maturation of the pterygomaxillary (PMS), zygomaticomaxillary (ZMS), transpalatal (TPS), and midpalatal (MPS) sutures. Based on the maturation of these four junctions, four independent observers had to determine whether they would prefer ORPE or SARPE to widen the maxilla.

RESULTS

For the PMS, the results show a closure of 83-100% from 13 to 17 years. As for the TPS, a closure of 78-85% was observed from 15 years of age. For the 15- to 17-year-old females, a closed ZMS was present in 32-47%. Regarding MPS, closed sutures presented in 61% (stages D and E) of the 15-year-old females. The cut-off age at which SARPE was recommended was 15.1 years for the orthodontist observers and 14.8 years for the maxillofacial surgeon observers.

CONCLUSIONS

Significant maturation of MPS was reached at the age of 15 in a female population. The PMS, TPS, MPS, and ZMS closed sequentially. A comprehensive diagnostic approach is necessary for choosing the appropriate treatment. When in doubt, age could assist decision making in a female population, with a cut-off age of 15 years in favor of SARPE based on this study.

Do the miniscrews of the prefabricated systems for the "appliance first" protocol of miniscrew-assisted rapid palatal expansion have lengths that meet the palatal thickness of patients?

INTRODUCTION

In the "appliance first" protocol of miniscrew-assisted rapid palatal expansion, the prefabricated shape of the expanders limits the potential locations for miniscrew placement. Considering the influence of palatal thickness on the selection of the optimal length of miniscrews, this study aimed to evaluate the thickness of both bone and mucosa of the palate of patients aged 6-65 years and suggest optimal lengths of miniscrews for this approach.

METHODS

Two hundred and eighty-two cone-beam computed tomography of patients of both sexes were divided into 3 groups according to age. The thicknesses of bone and mucosa were measured in the anterior and posterior regions of the palate.

RESULTS

Males showed a greater thickness of palatal bone than females. The thickness of both bone and mucosa was greater in the anterior region of the palate. The young patients showed greater bone thickness than adults and mature adults. The mature adults showed thinner bone thickness in the posterior region of the palate and greater mucosal thickness along the palate than young patients and adults. Development of miniscrews with longer thread lengths is necessary. Miniscrews with a 3-mm thread length would prevent excessive extravasation in the posterior region of the palate.

CONCLUSIONS

The thickness of both bone and mucosa of the palate is variable and influenced by sex and age. Manufacturing additional miniscrews with different lengths of thread is suggested to achieve bicortical anchorage in patients undergoing the "appliance first" protocol of miniscrew-assisted rapid palatal expansion.

Factors related to microimplant-assisted rapid palatal expansion in teenagers and young adults: A cone-beam computed tomography study

INTRODUCTION

For patients with maxillary transverse deficiency, selecting an appropriate therapeutic method is important for the treatment effect and prognosis. Our study aimed to explore factors related to microimplant-assisted rapid palatal expansion (MARPE) in teenagers and young adults using cone-beam computed tomography.

METHODS

Twenty-five patients who underwent MARPE were included in this retrospective study from February 2014 to June 2019. Midpalatal suture density (MPSD) ratio, midpalatal suture maturation (MPSM), bone effect, dentoalveolar effect, and dental effect in maxillary first molar were evaluated using cone-beam computed tomography. Spearman correlation analysis was used to analyze the correlation between the MPSD ratio, MPSM, age, and the expansion amount generated by MARPE.

RESULTS

Twenty-five patients (mean age, 19.84 ± 3.96 years; range, 15-29 years) with maxillary transverse deficiency were analyzed. Age was negatively correlated with bone expansion, alveolar expansion, and alveolar change (all P <0.05). There was a negative correlation between MPSM and nasal cavity variation, bone expansion, and alveolar change (all P <0.05). The bone expansion was negatively correlated with MPSD ratio 3 (r = -0.417; P <0.05) and MPSD ratio 4 (all P <0.05).

CONCLUSIONS

Age, MPSM, and MPSD ratio were significantly related to the MARPE effect. Age, MPSM, and MPSD ratio should be considered when choosing MARPE.

Aligner hybrid orthodontic approach to treat severe transverse divergence in an adolescent girl: A case report

OBJECTIVE

To resolve a complex Class II case with unilateral crossbite through an aesthetic approach, namely a hybrid orthodontic treatment combining aligners with miniscrews and auxiliaries.

MATERIALS AND METHODS

A 14-year-old hypodivergent female patient with dental Class II and posterior crossbite presented for orthodontic treatment. The patient refused conventional fixed multibracket treatment and was therefore prescribed aligners used in association with miniscrews and sectional lingual appliances. Pre- and post-treatment records and 2-year follow-up records are presented.

RESULTS

Treatment objectives, namely ideal occlusion and improved profile, were achieved in 12 months. Post-treatment panoramic radiography showed good root parallelism, and no sign of either crestal bone height reduction or apical root resorption. The patient was satisfied with the functional and aesthetic outcomes, which were stable at 2 years.

CONCLUSION

This case report illustrates that a hybrid aligner approach may be used to treat posterior crossbite and class II malocclusion with reduced treatment times, optimal oral hygiene and excellent aesthetics.

The comparison of the morphology of the mid-palatal suture between edentulous individuals and dentate jaws shows morphological differences

BACKGROUND

A profound understanding of the evolution and anatomy of the viscero- and neurocranium is quintessentially important for orthodontists. This particularly alludes to structures, which are directly targeted by orthodontic therapy such as the maxilla and the mid-palatal suture. The anatomy of the mid-palatal suture of toothed individuals is well described, whereas little is known about sutures' morphological changes after tooth loss. Therefore, the aim of this study was to evaluate the edentulous mid-palatal suture by means of histologic and histomorphometric analysis.

METHODS

Ten mid-palatal sutures of edentulous donors as well as six age- and sex matched dentulous controls were examined. For the histological and histomorphometric analysis (sutural width, obliteration, vascularization and interdigitation) conventional staining protocols (HE, Movat-Pentachrome, Sirius Red) and immunofluorescence (vWF, TRAP) were performed. Histomorphometric analysis was carried out using NIS-elements imaging software.

RESULTS

When compared to dentulous controls, the edentulous investigation group showed a decreased vascularization and sutural width as well as an increased sutural obliteration. Notably, a high variability and inhomogeneity within regard the histomorphometric parameters was seen in edentulous samples.

CONCLUSIONS

The mid-palatal suture of edentulous individuals showed significant morphological differences compared to individuals with toothed jaws. The loss of teeth and thereby functional loading seems to have a considerable impact on sutures' morphology.

Effect of Low-Level Laser Therapy on Bone Formation in Rapid Palatal Expansion: A Systematic Review

Introduction: Crossbite is a common malocclusion with a 7-23% prevalence rate. Treatment is based on the expansion of the mid-palatal suture (MPS) with Rapid Palatal Expansion(RPE) followed by a retention period to reach new bone maturation, enough to maintain the results stable. This systematic review was conducted to evaluate the effectiveness of low-level laser therapy (LLLT) in increasing bone formation in MPS. Methods: This article was written by the PRISMA checklist. Electronically, 3 databases, namely PubMed, Scopus, and Embase, were searched with the keywords selected based on PICO. Time (2010-2021) and language restrictions were performed. Results: 528 articles, out of which 374 studies were screened, were found, and 9 full-text articles were subsequently included considering these inclusion criteria: randomized clinical trial (RCT) that examines the efficacy of LLLT in rapid palatal expansion (RPE), age under 15 years, non-surgical RPE with a tooth-supported appliance, and low-intensity laser application. Finally, 4 articles were appraised by Cochrane version 5.2.0 with 7 domains. 3 of 4 articles showed LLLT has a significant impact on bone formation. One of them showed no significant difference in pain perception and bone density between the laser and non-laser groups. Conclusion: While many studies have assessed the effect of LLLT on bone formation in animal models, high-quality clinical trials are missing in this regard. The available clinical trials suggest a positive effect of LLLT on sutural bone formation after RPE.

The success and effectiveness of miniscrew-assisted rapid palatal expansion are age- and sex-dependent

OBJECTIVES

This study aimed to assess the success rate and the amount of suture separation after the miniscrew-assisted rapid palatal expansion (MARPE) procedure in relation to the chronological age and sex of the patients.

MATERIALS AND METHODS

The periapical radiographs of 215 subjects (95 male; 120 female; range, 6-60 years) who had undergone MARPE treatment were retrospectively analyzed. The success of suture separation was determined and, in suture-separated subjects, the amount of suture separation was evaluated by suture separation ratio calculated from the periapical radiograph obtained after active expansion. Association tests were performed using linear-by-linear association, the Jonckheere-Terpstra test, Fisher's exact test, and the Mann-Whitney U test, and linear regression models were also developed.

RESULTS

The success rate of suture separation was 61.05% in male, 94.17% in female, and 79.53% in both sexes. There was a statistically significant association between older age and suture nonseparation in male (p < 0.001), but not in female (p = 0.221). In suture-separated subjects, there was a statistically significant trend toward a low amount of suture separation with older age subgroups in both sexes (p < 0.001); however, there was no statistically significant difference in the amount of suture separation between male and female in all age subgroups.

CONCLUSIONS

Older patients treated with MARPE, particularly in male, may have a reduced likelihood of both success in suture separation and sufficient basal bone expansion.

CLINICAL RELEVANCE

This study demonstrates that clinicians should consider that the success rate of MARPE and the amount of suture separation may depend on chronological age and sex.

Maturity evaluation of orthodontically important anatomic structures with computed tomography

BACKGROUND/OBJECTIVES

The success of the orthopaedic treatment is closely related to the patient's skeletal maturation. This study aimed to evaluate the midpalatal suture (MPS), the zygomaticomaxillary suture (ZMS) maturation, and the closure degree of the spheno-occipital synchondrosis (SOS) in patients of different age groups. The presence of a correlation between these parameters and the palatal dimensions was also verified.

SUBJECTS/METHODS

The study was based on computed tomography images of 314 patients between 7 and 30 years of age with no orthodontic treatment history. The images were retrieved from the archive of the Radiology Department of Bezmialem Vakif University Hospital and divided into six groups according to the patient's age: 7-10, 11-13, 14-16, 17-20, 21-25, and 26-30 years. The maturation scores of ZMS, SOS, and MPS were determined, and palatal thickness and length were recorded. The data were analysed by using Statistical Package for Social Sciences for Windows 22.0.

RESULTS

A positive relationship was found between SOS closure degree and MPS/ZMS maturation (MPS-ZMS: r = 0.816, MPS-SOS: r = 0.736, ZMS-SOS: r = 0.868, P = 0.000). The degrees of ZMS and MPS maturation were significantly increased as the SOS closure degree increased. The MPS maturation score was significantly lower in patients with a short and thick palate (MPS-palatal thickness: r = 0.405, MPS-palatal length: r = 0.387, P = 0.000).

CONCLUSIONS

A positive correlation indicated the simultaneous progress in the maturation of the SOS, MPS, and ZMS. Moreover, the ANS-PNS length increase was found to be correlated with the increase of the MPS, ZMS, and SOS maturation scores. In contrast, a negative correlation was observed between the palatal thickness and the maturation stage of these structures.

Maturation stages of the sutures in the median palatine evaluated with cone-beam computed tomography

INTRODUCTION

This study aimed to evaluate the influence of age, sex, and facial growth patterns on the maturation stage of midpalatal sutures.

METHODS

We selected 90 total skull cone-beam computed tomography scans and divided them into the following 3 groups: brachyfacial (n = 30), mesofacial (n = 30), and dolichofacial (n = 30). These groups were determined using Ricketts VERT 3-dimensional cephalometric analysis. All patients were aged ≥18 years and were divided into those aged ≥30 years and >30 years. The maturational stage of the median palatine sutures was determined by evaluating the central transverse axial dimension in the maxillary-mandibular palate. Maturational stages were classified as A, B, C, D, and E.

RESULTS

Of the 90 images reviewed, 55 (61.1%) were female patients, and 35 were male patients (38.9%). The age of patients ranged from 18 to 59 years, with 55 patients aged <30 years (61.1%) and 35 aged ≥30 years (38.9%). Regarding the maturational stages, 3.3% of brachyfacial, 6.7% of mesiofacial, and 16.7% of dolichofacial subjects (P = 0.032) were classified as stages B and C.

CONCLUSIONS

The patients' facial patterns were found to be a significant signal for the maturation stage of midpalatal sutures. Adult dolichofacial patients are the most likely to have stage B and C.

Tomographic analysis of midpalatal suture prior to rapid maxillary expansion

INTRODUCTION

In Orthodontics and Facial Orthopedics, the timing of treatment onset may be critical and individual analysis should be applied to promote a favorable treatment planning. In this study, individual analysis of midpalatal suture (MS) and palatal measurements were performed in teenagers and young adult patients treated with rapid maxillary expansion (RME).

DESCRIPTION

Twenty-six patients submitted to RME with a tooth-supported appliance (Hyrax) were evaluated. The inclusion criteria were: minimum age of 14 years, presenting all posterior teeth, diagnosed with transverse maxillary discrepancy, and with a clinical indication for maxillary expansion. The pretreatment CBCT scans of these patients were assessed to obtain the stages of MS maturation (MSM); density ratio (MSD); and palatal length, thickness (anterior, intermediate and posterior) and sagittal area.

RESULTS

The maturation stages present were C, D or E; the density ranged from 0.6 to 1, and lower density (MSD < 0.75) and higher density (MSD ≥ 0.75) groups were determined. Individuals with higher MSD presented smaller sagittal area, compared to the lower density group. Individuals in D and E MSM stages presented smaller sagittal area and intermediate thickness, compared to stage C.

CONCLUSIONS

Smaller palatal sagittal area was observed in the high MSD groups and in the stages D and E of MSM.

Rapid Palatal Expansion Should Not Be Trivialized: Two Case Reports of Unexpected Complications

Rapid maxillary expansion is one of the most common orthodontic procedures performed in the pediatric population, easy to accomplish and compliance free, therefore really effective. Nevertheless, a careful diagnosis and frequent clinical follow-up appointments are necessary during the first weeks of active treatment. The purpose of this article was to report two cases of unexpected complications during orthopaedic maxillary expansion, involving two 7-year-old female patients, one presenting a saddle nose with suborbital hematoma and the other one an asymmetric palatal expansion. In both cases, the clinical situation progressively relapsed during the months following expansion appliance removal.

Stress distribution and displacement of three different types of micro-implant assisted rapid maxillary expansion (MARME): a three-dimensional finite element study

Abstract

Background/objective

Until 2010, adults underwent surgical treatment for maxillary expansion; however, with the advent of micro-implant-assisted rapid maxillary expansion (MARME), the availability of less invasive treatment options has increased. Nevertheless, individuals with severe transverse maxillary deficiency do not benefit from this therapy. This has aroused interest in creating a new device that allows the benefit of maxillary expansion for these individuals. The aim of this study was to evaluate the efficacy of three MARME models according to tension points, force distribution, and areas of concentration in the craniofacial complex when transverse forces are applied using finite element analysis.

Materials and methods

Digital modeling of the three MARME models was performed. Model A comprised five components: one body screw expander and four adjustable arms with rings for mini-implant insertion. These arms have an individualized height adjustment that allows MARME positioning according to the patient’s palatal anatomy, thereby preventing body screw expander collision with the lateral mucosa in severe cases of maxillary deficiency. Model B was a maxillary expander with screw rings joined to the body, and model C was similar to model B, except that model C had open rings for the insertion of the mini-implants. Through the MEF (Ansys software), the stresses, distribution, and area of concentration of the stresses were evaluated when transverse forces of 7.85 N were applied.

Results

The three models maintained the following pattern: model C presented weak stress peaks with limited distribution and lower concentration area, model B obtained median stress peaks with better distribution when compared to that of model C, and model A showed better stress distribution and larger concentration area. In model A, tensions were located in the lateral lamina of the pterygoid process, which is an important site for maxillary expansion. The limitation of the present study was that it did not include the periodontal tissues and muscles in the finite element method evaluation.

Conclusions

Model A showed the best stress distribution conditions. In cases of severe atresia, model A seems to be an excellent option.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40510-021-00357-5.

Association of the mid-palatal suture morphology to the age and to its density: A CBCT retrospective comparative observational study

OBJECTIVE

The twofold aim of the present investigation was to: 1. evaluate the degree of mid-palatal suture (MPS) maturation via CBCT in relation to patient age, and 2. to determine whether there was a correlation between quantitative (i.e., suture density) and qualitative (i.e., suture morphology) analysis.

MATERIALS AND METHODS

The stage of mid-palatal suture maturation and suture density ratio were assessed for 160 subjects on CBCTs using five qualitative stages proposed by Angelieri with the addition of three additional stages (i.e., B/C, C/D and D/E) and quantitative grey density scores of Grünheid MPS1,2,3,4 with the addition of parasutural bone and soft palate. The repeatability of both methods was evaluated using Cohen's K.The relationship between midpalatal suture maturation and age was assessed using ANOVA and Classification and Regression Trees (CART) analysis and tabulation and a χ² test for quantitative and qualitative analysis respectively. Statistical significance was assessed using a 5% threshold.

RESULTS

The final sample included 160 CBCTs (80 male,80 female; mean age 23.2±13.5). Both methods were found to be correlated and highly repeatable. In addiction they showed an age-related correlation in MPS morphology.

CONCLUSION

The mid-palatal suture density ratio and the stage of mid-palatal suture maturation has the potential to become useful in clinical practice. In fact, despite the correlation between MPS maturation stage and age, the latter parameter cannot be used as a clinical discriminator due to the great variability between subjects. It is therefore advisable to assess each patient individually on CBCT scans in order to determine treatment choices.

Computational Fluid Dynamics Analysis of Nasal Airway Changes after Treatment with C-Expander

The use of the C-expander is an effective treatment modality for maxillary skeletal deficiencies which can cause ailments and significantly reduce life expectancy in late adolescents and young adults. However, the morphological and dynamic effects on the nasal airway have not been reported. The main goal of this study was to evaluate the nasal airway changes after the implementation of a C-expander. A sample of nine patients (8 females, 1 male, age range from 15 to 29 years) was included. The morphology parameters and nasal airway ventilation parameters of pretreatment and posttreatment were measured. All study data were normally distributed. A paired t-test was used to evaluate the changes before and after treatment. After expansion, the mean and standard deviation values of intercanine maxillary width (CMW) and intermolar maxillary width (MMW) increased from 35.75 ± 2.48 mm and 54.20 ± 3.17 mm to 37.87 ± 2.26 mm (P < 0.05) and 56.65 ± 3.10 mm (P < 0.05), respectively. The nasal cavity volume increased from 20320.00 ± 3468.25 mm³ to 23134.70 ± 3918.84 mm³ (P < 0.05). The nasal pressure drop decreased from 36.34 ± 3.99 Pa to 30.70 ± 3.17 Pa (P < 0.05), while the value of the maximum velocity decreased from 6.50 ± 0.31 m/s to 5.85 ± 0.37 m/s (P < 0.05). Nasal resistance dropped remarkably from 0.16 ± 0.14 Pa/ml/s to 0.08 ± 0.06 Pa/ml/s (P < 0.05). The use of C-expander can effectively broaden the area and volume of the nasal airway, having a positive effect in the reduction of nasal resistance and improvement of nasal airway ventilation. For patients suffering from maxillary width deficiency and respiratory disorders, a C-expander may be an alternative method to treat the disease.

Effectiveness of Dental and Maxillary Transverse Changes in Tooth-Borne, Bone-Borne, and Hybrid Palatal Expansion through Cone-Beam Tomography: A Systematic Review of the Literature

Background and Objectives: Palatal expansion is a common orthodontic technique able to increase the transverse changes for subjects with constricted maxillary arches. The aim of the present investigation was to evaluate through a systematic review the tomography effectiveness of different palatal expander approaches. Materials and Methods: The database used to perform the screening and determine the eligibility of the clinical papers was PubMed (Medline). Results: The database search included a total of 284 results, while 271 articles were excluded. A total of 14 articles were included for the qualitative assessment. Conclusions: The effectiveness of the present studies reported that skeletal expansion was a useful approach to increase the transverse changes for subjects with constricted maxillary arches.

Midpalatal suture density ratio: Assessing the predictive power of a novel predictor of skeletal response to maxillary expansion

INTRODUCTION

Rapid maxillary expansion (RME) is a common orthodontic treatment to correct maxillary transverse deficiency; however, the inability to determine the precise timing of fusion of the midpalatal suture creates difficulty for clinicians to prescribe the appropriate treatment, surgical or nonsurgical expansion. The purpose of this study was to assess the predictive power of the midpalatal suture density ratio (MPSD) for a skeletal response to RME.

METHODS

Pre- and posttreatment cone-beam computed tomography scans were obtained from 78 orthodontic patients aged from 8 to 18 years treated with RME. MPSDs were calculated from pretreatment scans, and a prediction was made for the amount of skeletal expansion obtained at the level of the palate after comprehensive orthodontic treatment. Predicted values were compared with actual outcomes as assessed from posttreatment scans, followed by regression analyses to investigate correlations between MPSD and skeletal expansion and equivalence testing to analyze the performance of the predicted measurements.

RESULTS

The MPSDs were not statistically significantly (P >0.05) correlated with the amount of skeletal expansion achieved. In addition, the predicted skeletal expansion using MPSD was not statistically equivalent to the skeletal expansion achieved using an equivalence margin of ±0.05.

CONCLUSIONS

The results suggest that the MPSD obtained from pretreatment cone-beam computed tomography scans were not correlated well enough with the amount of skeletal expansion achieved to be an effective predictor of the amount of long-term skeletal expansion after RME.

Correlation assessment of cervical vertebrae maturation stage and mid-palatal suture maturation in an Iranian population

AIM

The aim of the current study was to evaluate the correlation of skeletal age based on cervical vertebrae maturation (CVM) stage and mid-palatal suture (MPS) maturation in an Iranian population.

MATERIAL AND METHODS

This was a cross-sectional analytic study. A total number of 93 samples were included. Samples were taken from patients who were in CS3 to CS6 stages of CVM who had cone-beam computed tomography and lateral cephalometry based on inclusion criteria. The maturation of MPS was assessed based on the cone-beam computed tomography images. In the classification of maturation of MPS, there are five stages (A-E) and the suture fusion occurs in stage D. In stage E, the suture is fused completely. The CVM stage (CS1-6) was also assessed based on the lateral cephalograms. Data were analyzed using Spearman correlation with a significance level of 0.05.

RESULTS

A total of 51 female individuals with a mean age of 14.98 ± 4.806 and 42 male individuals with a mean age of 15.79 ± 5.135 participated in this study. The correlation coefficient between the CVM stage and MPS maturation was 0.691 in female and 0.754 in male individuals (P < 0.001). Stage D was correlated with CS4.

CONCLUSION

The results demonstrated that CVM stages had a significant but moderate positive correlation with the maturation of MPS. Until CS3, the MPS has not been fused and in CS6 the MPS is fused definitely.

Variability of the maxillary suture maturation and density in the subjects with different sex and growth status

INTRODUCTION

The objective of this study was to classify median palatine suture (MPS) maturation type in young and adult patients. Additionally, we compared MPS maturity type and density based on sex and growth status.

MATERIALS AND METHODS

In this retrospective cone beam computed tomography study, we included a total of 221 subjects, grouped based on sex and growth status. Once scans were aligned and oriented in the sagittal view, we conducted our evaluations on the axial sections. Based on interdigitation and shape, the MPS were categorized into Maturation Types A through E. Additionally, MPS density was measured as Hounsfield unit equivalent pixel intensity value scale for anterior and posterior sutural regions.

RESULTS

The majority of male (39%) and female (42%) subjects had MPS Maturation Type C. A maximum number of growing (42%) patients had Type C and nongrowing subjects (39%) had Type E sutures. The sex comparison showed significantly lower (p < .001) MPS density for both anterior and posterior regions in males when compared to females. Additionally, for the posterior region, nongrowing males had significantly lower (p < .001) MPS density when compared to nongrowing females. Subgroup comparisons of the MPS densities between growing and nongrowing males and growing and nongrowing females showed a significant difference (p < .001).

CONCLUSION

Classification of the MPS based on the maturation types provides a reliable predictor for orthodontic treatment planning. MPS density is significantly higher in females as compared to males. Similarly, nongrowing individuals have significantly higher MPS density compared to growing individuals for both anterior and posterior locations.

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

INTRODUCTION

This study aimed to evaluate the efficacy of fractal analysis of hand-wrist radiography in the decision of conventional or surgery-assisted rapid palatal expansion (RPE).

METHODS

The study included 48 patients who underwent the RPE procedure. Study groups were as follows: group 1 (successful conventional RPE [n = 24, 5 male and 19 female patients; mean age ± standard deviation, 15.85 ± 0.97 years]) and group 2 (failed conventional RPE [n = 24, 5 male and 19 female patients; mean age ± standard deviation, 15.96 ± 1.08 years]). Fractal dimension (FD) analysis was conducted on hand-wrist radiographs of the patients for 4 different regions: the epiphysis-diaphysis line of the radius bone and the proximal, medial (MP3), and distal (DP3) phalanxes of the middle finger. A Student t test was performed to compare fractal values between the groups. A receiver operating characteristic analysis was applied to determine the optimal cutoff value of FDs. In addition, a Pearson correlation coefficient was calculated to evaluate the relationship between the fractal values and either age or hand-wrist stage in a second sample group (n = 90; age range, 8.7-18.7 years).

RESULTS

Fractal values of the radius, MP3, and DP3 were significantly increased in the failed conventional RPE group (P <0.05). The optimal cutoff value of the FD for predicting the success of conventional RPE was 1.16 in the radius, 1.18 in proximal phalanxes, 1.29 in MP3, and 1.08 in DP3. There was a positive correlation between fractal values of the radius and age or hand-wrist stages (P <0.05).

CONCLUSIONS

Within the limits of this study, results revealed that fractal analysis of hand-wrist radiographs might be considered a significant tool in the prediction of RPE success.

Relationship between the Condylion-Gonion-Menton Angle and Dentoalveolar Heights

An accurate estimation of both facial growth and the dentoalveolar dimension is key to successful treatment. The aim of this study was to analyze the relation between the Condylion–Gonion–Menton angle (CoGoMe^) and dentoalveolar heights in a population of patients from southern Italy. This retrospective study analyzed 270 cephalograms of 115 males (42.1%, mean age 15.5 ± 5.2 years) and 155 females (57.9%, mean age 15.6 ± 5.9 years). The facial divergency was evaluated with the Sella–Nasion and Gonion–Gnation angle (SN^GoGn), mandibular structure with the CoGoMe^, and dentoalveolar heights were assessed in four measurements: upper anterior (UADH), lower anterior (LADH), upper posterior (UPDH), and lower posterior (LPDH). Data were analyzed by means of Pearson’s correlation and linear regression model (p < 0.05). All the dentoalveolar heights were strongly correlated among them (p < 0.001). The UADH was correlated with the SN^GoGn (r = 0.145; p = 0.017), while the LPDH was correlated with the CoGoMe^ (r = −0.183; p = 0.003). Moreover, there was a positive association between the UADH and the SN^GoGn (B = 0.08; 95% CI: 0.014–0.144; p = 0.017), and a negative association between the CoGoMe^ and the LPDH (B = −0.098; 95% CI: −0.161–0.035; p = 0.003). Facial divergency and mandibular structure are associated with dentoalveolar heights.

Midpalatal suture maturation stage assessment in adolescents and young adults using cone-beam computed tomography

Background

The aim of this study was to evaluate the midpalatal suture maturation stages in adolescents and young adults using cone-beam computed tomography (CBCT).

Methods

The sample comprised 200 CBCT scans of individuals aged 10 to 25 years old (95 males and 105 females) divided into three groups, adolescents (n = 48), post-adolescents (n = 52), and young adults (n = 100). The Planmeca ProMax 3D software was used for the midpalatal suture maturation stage evaluation according to Angieleri’s method, using cross-sectional axial slice. Two previously calibrated examiners analyzed the images and classified according to five different maturation stages. A, B, and C stages were considered with open midpalatal suture, and D and E were considered without open midpalatal suture. Association tests were performed using chi-square test also, and a binary logistic regression was evaluated (P < 0.05).

Results

The possibility to find open midpalatal suture in individuals of 10 to 15 years old was 70.8%, in subject aged 16 to 20 and 21 to 25 years old was 21.2% and 17%, respectively. Furthermore, this possibility in individuals older than 16 years was greater in males than in females.

Conclusions

The possibility to find open midpalatal suture in post-adolescents and young adults is greater than the orthodontists considered years ago. Furthermore, men are more likely to find midpalatal suture opening. These implications might be considered by the orthodontists when maxillary expansion is required. Besides, the ossification of the middle palatal suture is very variable, and therefore, the use of CBCT might be recommended to clarify this possibility.

Rapid maxillary expansion outcomes according to midpalatal suture maturation levels

BACKGROUND

This study aims to compare the relationship between skeletal and dental outcomes of rapid maxillary expansion (RME) treatment on cone beam computed tomography (CBCT) images between pre-pubertal peak (pre-peak) and post-pubertal peak (post-peak) patients. The null hypothesis was that there was no difference in the outcomes of RME treatment between the groups.

METHODS

Thirty-two patients who underwent RME treatment were classified according to midpalatal suture maturation levels and then divided into two groups as pre-peak and post-peak. Skeletal and dental measurements were performed on the CBCT images at T0 (pre-treatment stage) and at T1 (post-treatment stage). Paired sample t test was used to evaluate normally distributed data and P < 0.05 was taken as the significance level.

RESULTS

There were significant differences between T0 and T1 within the groups, but the changes between the pre-peak and post-peak patient groups were not statistically significant.

CONCLUSION

Non-significant changes were found between the two groups, and the null hypothesis was excepted.

Three-dimensional stereophotogrammetric analysis of nasolabial soft tissue effects of rapid maxillary expansion: a systematic review of clinical trials

The aim of this systematic review is to analyse the quality and clinical evidence in the literature analysing, through 3D stereophotogrammetry, the nasolabial soft tissue modifications that may occur after rapid maxillary expansion (RME). This systematic literature review was based on the PRISMA-P statement and was registered in the PROSPERO database with the following protocol ID: CRD42017079875. Pubmed, Cochrane, EBSCO, Scopus, Web of Science databases were searched with no restriction of year or publication status. Selection criteria were: randomised clinical trials, controlled clinical trials, cohort studies, cross-sectional studies, case-control studies on patients with unilateral/bilateral crossbite, transverse maxillary deficiency and crowding, treated with RME and monitored by 3D stereophotogrammetry. 652 articles were retrieved in the initial search. After the review process, 11 full-text articles met inclusion criteria. After the evaluation process, 4 publications were included for the present literature review. Due to the heterogeneous methodology meta-analysis was not possible; consequently, a systematic assessment of the studies and summary of the findings from the available evidence were used to answer the research question. The maximum widening of the alar cartilage is 1.41 ± 0.95 mm, whose clinical significance is open to question. The effect of RME on the mouth width remains controversial. In Altindis et al., the difference between pre-treatment and post-treatment mouth width (1.80 mm increment in the banded RME group) was statistically significant, while in Baysal 1.86 mm was considered a non-significant value. Inconsistencies and limitations in the study population and measurement protocols were detected between studies. These data underline the necessity for updated guidelines that allow to standardise, for this type of study, sample selection, measurement methods and collection of results.

Transverse Skeletal Effects of Rapid Maxillary Expansion in Pre and Post Pubertal Subjects: A Systematic Review

OBJECTIVE

The aim of this systematic review was to assess the transverse skeletal effects of rapid maxillary expansion (RME) in pre and post-pubertal subjects.

MATERIAL AND METHODS

Five databases were searched till May 2018; Pubmed, Cochrane, Scopus, Lilacs and Web of science in addition to the manual search of other sources. There were no language restrictions. Methodological Index for Non-Randomized Studies MINORS was used to assess the quality and risk of bias of the trials included.

RESULTS

Six studies were finally included in the qualitative analysis. A meta-analysis wasn't performed due to the heterogeneity of methodologies and outcomes. All of the included studies showed drawbacks in their structure yielding weak evidence. On the short term, RME caused an increase in the maxillary and lateral-nasal widths in pre-pubertal subjects by 3.4 mm and 3.3 mm, and by 2.8 and 2.2 mm respectively in post-pubertal subjects. Although statistically insignificant, the maxillary width increase was more than that of the post-pubertal subjects by 0.6 mm. Over the long term, expansion produced permanent increases in the transverse dimensions of both the dento-alveolar and skeletal components of the maxilla and circum-maxillary structures in pre-pubertal subjects. The post-pubertal subjects presented with a statistically significant increase only in the later-nasal width by 1.3 mm than the untreated controls with no permanent increase in the skeletal maxillary width.

CONCLUSION

The literature is very deficient regarding the use of skeletal age as a reference in the treatment of skeletal crossbites using RME. Only weak evidence exists supporting the increased maxillary and lateral-nasal widths after tooth-tissue borne RME in pre-pubertal subjects, with these effects being less in the post-pubertal ones.

Effect of Rapid Maxillary Expansion on Glenoid Fossa and Condyle-Fossa Relationship in Growing Patients (MEGP): Study Protocol for a Controlled Clinical Trial

Aims and Objectives:

Rapid maxillary expansion (RME) is an orthodontic nonsurgical procedure aiming at increasing the width of the maxilla by opening mainly the intermaxillary suture in patients presenting a transverse maxillary skeletal deficiency. The objectives of the current prospective controlled clinical and radiographic study are to evaluate the hypothesis that RME in growing patients will result in radiographic changes at the level of interglenoid fossa distance, condyle-fossa relationship, and nasal cavity widths compared to the group who received no treatment initially and served as untreated control.

Materials and Methods:

In this prospective controlled clinical and radiographic study, forty healthy growing patients selected from a school-based population following a large screening campaign, ranging in age between 8 and 13 years, presenting a maxillary constriction with bilateral crossbite, and candidates for RME are being recruited. The first group will include participants willing to undergo treatment (n = 25) and the other group will include those inclined to postpone (n = 15).

Results:

The primary outcome is to compare radiologically the interglenoid fossa distance and the condyle-fossa relationship; nasal cavity width will be a secondary outcome. A multivariable analysis of Covariance model will be used, with the assessment of the time by group interaction, using age as covariate. The project protocol was reviewed and approved by the Ethics Committee of the Lebanese University, National Institute in Lebanon (CUEMB process number 31/04/2015). The study is funded by the Lebanese University and Centre National de Recherche Scientifique, Lebanon (Number: 652 on 14/04/2016).

Conclusion:

This prospective controlled clinical trial will give information about the effect of RME on the glenoid fossa and condyle-fossa relationship and its impact on the nasal cavity width.

Trial Registration:

Retrospectively registered in BioMed Central (DOI10.1186/ISRCTN77788053).