Palatal growth studied on human autopsy material. A histologic microradiographic study

A novel system for classification for midpalatal suture ossification based on pseudocolored and multilayer reconstructed coronal slices: Indication for selection of maxillary expansion methods

INTRODUCTION

A novel method was established for the staging of midpalatal suture (MPS) ossification based on a pseudocoloring stack of anterior and posterior MPS coronal slices obtained by cone-beam computed tomography (CBCT).

METHODS

CBCT scans of 240 subjects aged 5-35 years were pseudocolor processed. The slice thickness of stacked anterior and posterior coronal observation planes was set at 5.0 mm. The ossification status of both anterior or posterior MPS was classified as the tunnel, partially ossified, or ossified type. MPSs were classified into 5 stages: stage I, anterior and posterior MPSs are the tunnel type; stage II, anterior and posterior MPSs are the tunnel and partially ossified type, respectively; stage III, anterior and posterior MPSs are the partially ossified type; stage IV, anterior and posterior MPSs are the tunnel or partially ossified type and ossified type, respectively; and stage V, anterior and posterior MPSs are the ossified type. The weighted κ value was used to assess the intraexaminer and interexaminer agreement of the MPS classifications.

RESULTS

Intraexaminer and interexaminer reliability of the proposed staging method was substantial. The largest proportions of patients aged 5-15 years and 16-35 years were classified as stages I and III, respectively. Among adults, 31.0% of males and 7.1% of females were classified as stage I or II.

CONCLUSIONS

The pseudocolor imaging technique and the stack of CBCT slices provide relatively intuitive and comprehensive information on MPS ossification. The novel classification of MPS ossification is expected to serve as an indication of the necessity of surgical intervention for maxillary expansion treatment.

Comparison of stress distribution and displacement pattern of maxillary expansion in craniomaxillary complex using rapid maxillary expander and maxillary skeletal expander: A finite element model analysis

INTRODUCTION

A combination of miniscrews and the maxillary skeletal expander (MSE) was created to address potential issues with the traditional rapid maxillary expander (RME). This study was conducted to assess and compare stress distribution and displacement patterns in the craniomaxillary complex during maxillary expansion using Rapid Maxillary Expander (RME) and Maxillary Skeletal Expander (MSE) using 3D Finite Element model.

METHODS

A 3D Finite Element model of the craniomaxillary complex, including the maxilla and maxillary dentition, was generated using computer aided design software. Stress distribution and displacement patterns were analysed for both RME and MSE treatments.

RESULTS

The results showed that MSE had greater bone displacement, bone stress, teeth displacement, teeth stress, and periodontal displacement and stress compared to RME. In terms of suture displacement, MSE had higher frontonasal suture displacement compared to RME. Teeth displacement showed that central and lateral incisors showed palatal displacement with RME and buccal displacement with MSE, while canine, premolars, and molars all showed greater buccal displacement with MSE compared to RME along the transverse axis. Central incisor displacement was observed in the extrusion direction with RME, while it was in the intrusion direction with MSE. In terms of teeth stress, MSE treatment resulted in higher stress on the central incisor, lateral incisor, canine, premolars, and molars compared to RME treatment.

DISCUSSION

Overall, MSE exhibited greater bone displacement, stress, and suture displacement/stress compared to RME. Additionally, MSE induced different tooth displacement patterns with higher stress on teeth compared to RME. These findings suggest differences in treatment outcomes and biomechanical effects between the two expansion methods.

Morphological characteristics of the palate according to mid-palatal suture maturational stage on cone-beam computed tomography images: A cross-sectional study

INTRODUCTION

Besides the mid-palatal suture maturation stage, the morphology of the palate might also play a role in the effectiveness of miniscrew insertion planning or effectiveness of palatal expansion.

OBJECTIVES

The aim was to assess the mid-palate length, height and surface area according to the mid-palatal suture maturation stage and its correlation to the maturity of the transverse palatine suture on cone-beam computed tomography (CBCT) maxillary images in a consequently selected group of subjects.

MATERIAL AND METHODS

High-resolution CBCT images of 100 subjects (56 females, 44 males), aged 33.9±22.7 years, were selected. The images were clustered according to the mid-palatal suture maturation stage (stages B, C, D, and E) and 25 images per stage group were retrieved. The length, heights (at 2mm intervals) and surface area of the mid-palate were measured from the posterior border of the incisal foramen to the posterior nasal spine, and the maturity of the transverse palatine suture was recorded.

RESULTS

No between-stage-group differences were seen for mid-palate length, while heights and surface areas were significantly different between maturational stages. The mid-palate height was significantly smaller in maturational stages D and E groups (5.65±1.55mm and 5.77±1.70mm, respectively) than in groups B and C (6.97±1.82mm and 7.00±1.53mm, respectively). However, differences were significant only distally to the sixth mm measurement point. The surface area was significantly different among groups, denoting higher values for stage B and C (1.82±0.55cm2 and 1.86±0.41cm2, respectively), compared to stage D and E groups (1.53±0.38cm2 and 1.57±0.54cm2, respectively). A significant negative but poor correlation was seen between mid-palate total average height, surface area and mid-palatal suture stage (rho=-0.278, P=0.005 and rho=-0.222, P=0.027, respectively). Moreover, a very strong to moderate positive correlation (rho=0.847, P<0.001, rho=0.739, P<0.001) was seen between age and the maturational stage of the mid-palatal and transverse palatine sutures, respectively. Both the mid-palatal and transverse palatine sutures maturity stages were positively and very strongly correlated (rho=0.839, P<0.001).

CONCLUSIONS

The height and surface area of the mid-palate were significantly different among the maturational stage groups, while no differences were observed regarding the mid-palate length. Less mature sutures exhibit greater height and surface area values than more mature sutures. Although further research is needed in this regard, the mid-palatal suture maturational stage C showed greater distribution variability in terms of the transverse palatal maturation stages, which might be a discriminating factor between successful and unsuccessful skeletal palatal expansion, even with the use of skeletal anchorage devices.

Midpalatal suture osteotomy combined with microimplant-assisted rapid palatal expansion for adult maxillary transverse deficiency treatment: a study protocol of a randomised controlled trial

INTRODUCTION

Maxillary transverse deficiency (MTD) is a common type of malocclusion. For adult MTD patients with highly ossified midpalatal sutures, surgically assisted rapid palatal expansion (SARPE) has been the conventional method of maxillary expansion. However, SARPE has the disadvantages of significant trauma, high cost and a high incidence of adverse events. Therefore, we proposed a novel minimally invasive method for maxillary expansion, which is midpalatal suture osteotomy combined with microimplant-assisted rapid palatal expansion (MSO-MARPE). The results are expected to confirm MSO-MARPE as a novel minimally invasive alternative to SARPE in skeletally mature MTD patients.

METHODS AND ANALYSIS

A prospective, single-centre, parallel-group randomised controlled trial will be conducted, enrolling 20 adult MTD patients. Participants will be randomised equally to the control and experimental groups. The control group will undergo a Lefort I and median osteotomy and postoperative maxillary expansion with a tooth-borne Hyrax-type expander. The experimental group will undergo a midpalatal suture osteotomy and postoperative maxillary expansion with a microimplant-assisted expander. A series of linear and angular parameters will be measured in the pre- and post-coronal planes before treatment (T0), immediately after expansion (T1) and 6 months after expansion (T2) to evaluate the efficacy of skeletal expansion and dental side effects. The study aims to compare the clinical and cost-effectiveness of SARPE and that of MSO-MARPE. The primary outcome is the contribution of posterior midpalatal expansion immediately after expansion. The secondary outcomes include nasal, sutural, alveolar and dental expansion, pain intensity, operative time and treatment costs. The safety indicator will be the number and incidence of adverse events. The interaction between the control group and the experimental group will be analysed using two independent-sample t-tests or Mann-Whitney U test, and the paired data at different time points will be analysed using paired t-test.

ETHICS AND DISSEMINATION

The trial protocol (version 6.0 13 December 2024) has been approved by the Institutional Review Board of the Ninth People's Hospital of Shanghai Jiao Tong University School of Medicine (approval number: SH9H-2023-T309-3). Results will be disseminated through peer-reviewed publications and presentations at scientific conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2400081545.

Transverse dentoalveolar development in Chinese children and adolescents: A cross-sectional study using revised Andrews' Element III analysis

INTRODUCTION

This study investigated the prevalence of maxillary transverse deficiency (MTD) in Chinese children and adolescents using revised Andrews' Element III analysis and studied transverse developmental characteristics of the maxillomandibular complex.

METHODS

Plaster or digital casts of 794 participants aged 7-18 years were evaluated. MTD was diagnosed when the maxilla-mandible width difference, represented by the decompensated maxillary and mandibular first molars, exceeded 4 mm.

RESULTS

The average prevalence of MTD among patients aged 7-18 years was 31.1%. Patients with MTD exhibited narrower maxillary and/or wider mandibular arches. Strikingly, 32.3% of participants with posterior crossbite because of local crowding or mandibular deviation were not diagnosed with MTD. Dental compensation, such as a greater buccolingual inclination of the first molars, was common in patients with MTD. Transverse growth of the maxillomandibular complex was completed by 17 years old, with the maxilla undergoing greater transverse growth than the mandible. The physiological buccolingual inclination of first molars was observed in patients without MTD. The 95% reference value of the palatal arch width was 31.9-42.3 mm.

CONCLUSIONS

The prevalence of MTD is 31.1% among Chinese children and adolescents. However, it is often camouflaged by dental compensation and sagittal discrepancy. The etiology of MTD is uncoordinated width in the maxillomandibular complex, which is not solely attributed to a narrow maxilla but also to an excessively wide mandible. To enhance diagnostic accuracy, individualized measurements of the maxillomandibular complex and a revised dental decompensation formula, rather than posterior crossbite alone, are recommended for transverse diagnosis. A potential presence of MTD is indicated when the palatal arch width is <31.9 mm.

Condylar changes in adult patients with unilateral posterior crossbite following microimplant-assisted rapid palatal expansion: A retrospective CBCT study

OBJECTIVES

This study aimed to assess the alterations in condylar positioning in adult skeletal Class I patients with unilateral posterior crossbite following microimplant-assisted rapid palatal expansion (MARPE) treatment.

METHODS

This retrospective study involving 30 participants (10 males, 20 females) with an average age 22.9 ± 4.2 years, ranged from 18.1 to 30.9 years, who were treated with a customized microimplant-supported rapid palatal expander. Pre-expansion and post- comprehensive orthodontic treatment CBCT images (20-26 ±2.1months) were analyzed to assess the condylar changes before and after treatment. We measured the temporomandibular joint (TMJ) in the three dimension in terms of: (1) The position and angle of the mandibular condyles; (2) How centralized the condyles were in their particular mandibular fossae; and (3) The volume of the TMJ and the joint spaces. To evaluate the differences between the T1 and T2 samples, we used the paired t-test and the Wilcoxon signed rank test.

RESULTS

Before treatment, minor differences were noted in the anterior joint space (AJS), superior joint space (SJS), and anteroposterior condylar joint position (APCJP) between the crossbite and non-crossbite sides, though these differences were not statistically significant. Post-treatment, the condyles on both sides assumed a more posterior position, yet significant asymmetry in the AJS persisted (P < .05). The crossbite-side condyle also showed a tendency to rotate toward the non-crossbite side in the anteroposterior direction. While MARPE affected specific aspects of condylar positioning, achieving complete alignment remained challenging.

CONCLUSION

This study provides insightful observations on the enduring impacts of MARPE on TMJ spaces and position in adult patients suffering from a unilateral posterior crossbite.

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.

Age-dependent effects of Delaire facemask therapy for class III malocclusion : Impact on maxillary sutures and palatal morphology

BACKGROUND AND AIM

Treatment effects of a combined rapid maxillary expansion (RME) and Delaire facemask (DFM) therapy have so far only been scientifically investigated through cephalometric analyses. The combination of cephalometric, dental cast and cone-beam computed tomography (CBCT) scan analysis was not yet used for investigating morphologic changes of the tooth-bearing palate. The aim of the present study was to determine whether patient age at treatment begin has an influence upon palatal length changes after RME/DFM therapy, and to what extent transverse palatal sutures contribute to these.

PATIENTS AND METHODS

In n = 6 patients (min 10.5 years, max 14.7 years) from a total group of n = 40, CBCT datasets showing all palatal sutures were visually assessed, and palatal morphology was compared with a dental cast analysis. In addition, lateral cephalograms and dental casts of n = 40 patients were divided into two groups (PG1: < 12 years, n = 20; PG2: ≥ 12 years, n = 20), and an analysis was performed to investigate changes in the tooth-bearing palate after RME/DFM treatment.

RESULTS

The CBCT analysis showed that the median and transverse palatine sutures were always open. On the contrary, the pterygopalatomaxillary sutures were partially open only in the youngest patients. The transverse palatal suture showed age-dependent morphologic changes in the transverse and sagittal planes. The changes of the palatal width and length show clear differences between the two younger and the four older patients in the corresponding dental cast analysis. The cephalometric analysis showed that a significant improvement of the sagittal jaw relation due to ventral displacement of the maxilla during treatment occurred only in younger patients (< 12 years) despite similar initial findings in both patient groups. The dental cast analysis also revealed that changes are age-dependent: In PG1, the width increases posteriorly more than anteriorly; in PG2, this is reversed. The length increases are always significant in both patient groups, whereby the anterior, posterior, and total amounts are greater in PG1 than in PG2. In relative terms, the increases in both groups are greater posteriorly than anteriorly. There is a significant difference between the groups posteriorly and overall.

CONCLUSIONS

Morphological changes of the sutures appear to have a decisive influence on the success of RME/DFM therapy. The age-dependent reactions of pterygopalatomaxillary and transverse palatine sutures represent a further main therapeutic effect of DFM treatment in addition to those described by Delaire and explain the different changes in palate length before and after the age of 12. If the maximum effect of RME/DFM treatment is desired, it should be started before the age of 12. Treatment success is age-dependent.

Relative contributions of genetic and environmental factors to palatal morphology: a longitudinal twin study

OBJECTIVES

This study aimed to determine the genetic and environmental contributions to phenotypic variations of palatal morphology during development.

METHODS

Longitudinal three-dimensional digital maxillary dental casts of 228 twin pairs (104 monozygotic and 124 dizygotic) at primary, mixed, and permanent dentition stages were included in this study. Landmarks were placed on the casts along the midpoints of the dento-gingival junction on the palatal side of each tooth and the mid-palatine raphe using MeshLab. Palatal widths, depths, length, area, and volume were measured using those landmarks. Univariate genetic structural equation modelling was performed on twin data at each stage of dental development.

RESULTS

Except for anterior depth, all palatal dimensions increased significantly from the primary to permanent dentition stages. The phenotypic variance for most of the palatal dimensions during development was best explained by a model, including additive genetic and non-shared environment variance components. Variance in volume and area in the primary dentition stage was best explained by a model including additive genetic, shared environment, and non-shared environment variance components. For posterior palatal depth and width, narrow-sense heritability estimates were above 0.8 for all dental developmental stages. In contrast, heritability estimates for other palatal traits fluctuated during development.

LIMITATION

This study was limited to twins of European ancestry.

CONCLUSIONS

Additive genetic and non-shared environmental factors primarily influenced palatal morphology during development. While the genetic influence on different aspects of the palate varied throughout development, it was particularly strong in the posterior region of the palate and during the permanent dentition stage.

Evaluation of midpalatal suture maturation stage in 5- to 20-year-olds using cone-beam computed tomography

INTRODUCTION

This study aimed to evaluate the midpalatal suture (MPS) maturation stages using the cone-beam computed tomography classification method in Chinese children aged 5-10 years, adolescents aged 11-15 years, and postadolescents aged 16-20 years and identify a correlation between maturation stage and age and sex.

METHODS

Axial sections of tomographic images from 717 participants (369 female and 348 male participants) aged 5-20 years were used to classify the maturation stage of the MPS (stages A, B, C, D, and E). Kappa statistics were used to evaluate the measurement error. The chi-square test was applied to analyze the differences in the distribution of MPS stages by age group and by sex among all participants, as well as the adolescent group. The Fisher exact test was employed to assess the differences in MPS stage distribution by sex among children aged 5-10 years and among the postadolescent group. The Mann-Whitney U test was used to assess the potential variance in age distribution between stages C and D.

RESULTS

The most prevalent maturation stage was stage C (40.3%). Of the total population, 69.4% had MPS in stages A, B, or C. A significant difference in age distribution was observed between stage C and stage D (P <0.001). The distribution of the MPS maturation stage significantly varied by age group (P <0.001) and sex (P <0.001).

CONCLUSIONS

The distribution of participants in advanced maturation stages increases with age. Female patients generally experience earlier MPS maturation than male patients, particularly between the ages of 11-20 years.

Three-dimensional digital imaging analysis of the palatal bone thickness for orthodontic mini-implant insertion - determination of the safe zone and angulation

BACKGROUND

In order to successfully perform orthodontic mini-implant procedures successfully for the subsequent anchoring of orthodontic appliances, it is crucial to know the palatal bone thickness. This is usually assessed using two-dimensional radiographs. The purpose of this study was to use a three-dimensional digital imaging measurement method to provide information on palatal bone volume and bone thickness and to make recommendations on the optimal and safe insertion site and angle for palatal mini-implants.

METHODS

For this observational, cross-section study, pre-existing cone beam computed tomography scans of 184 patients were converted into 3D Standard Tessellation Language (STL) models of the maxilla. The area between the canine and the first molar was divided into 6 regions of interest (ROIs), three on the left side of the palate and three on the right side. The bone thickness of the palate was analyzed volumetrically and linearly while simulating different mini-implant insertion angles of 0°, 10°, 20° and 30° degrees relative to the palatal surface.

RESULTS

Among the ROIs, the greatest mean bone thickness was observed in the region of the first premolars with a mean distance (MD) of 10.44 ± 2.53 mm and decreased from anterior to posterior (MD: 3.44 ± 1.16 mm). The highest volume (Vol) values were also measured in the anterior palatal region (Vol: 1127.26 ± 483.91 mm3), while there was also a decrease in the posterior region (Vol: 394.36 ± 180.22 mm3). Regarding the simulated palatal mini-implant insertion sites, the greatest bone thickness was found in the anterior region, at the level of the canines with an angle of 0° (MD: 12.25 ± 3.75 mm). In the more posterior region, at the level between the first and second premolars, the greatest bone thickness was observed at an angle of 30° (MD: 7.93 ± 3.81 mm). Gender differences were found.

CONCLUSION

This clinical study showed that the paramedian region at the level of the first premolar is the safest site for orthodontic mini-implant placement as evaluated by three-dimensional measurements. The results showed that implant insertion angle, gender and age are important aspects to consider when planning and inserting orthodontic palatal mini-implants.

TRIAL REGISTRATION

N.a.

Miniscrew-assisted Rapid Palatal Expansion Before Orthognathic Surgery for a Patient With Laterognathia

In this case report, a 19-year-old male patient with maxillary transverse deficiency, concave profile, and facial asymmetry is presented. In the case of transversal insufficiency, nonsurgical maxillary expansion was performed with the miniscrew-assisted rapid palatal expansion (MARPE) appliance to reduce the number of surgeries and provide both dentoalveolar and skeletal expansion. The periodontal soundness and short-term stability of the maxillary expansion were confirmed both clinically and radiologically. Mandibular prognathism was later corrected with orthognathic surgery. MARPE is an effective approach to the treatment of maxillary transverse deficiencies in adult patients.

The current overview of the devices of temporary anchorage placed on the palatal bone: CBCT study

Temporary anchorage devices (TADs) are frequently applied to different anatomic areas with different protocols to increase skeletal effects and anchorage in orthodontic treatment planning. It has been reported in many literatures that primary stability for orthodontic TADs is significant for long-term survival rate. For this reason, different areas of the palatal region, which has many indications, have been widely used in the studies. In this evaluation where bone quality and thickness are important, density, bone thickness, and fractal dimension (FD) on cone beam computed tomography (CBCT) will provide more predictable clinical results. The aim of this study was to evaluate bone thickness, density, and FD in the palatal region of the first, and second premolars, and first molars. There was a remarkable difference (p < 0.05) between the parameters of FD, thickness and density of bone in the identified areas in the palatal region. In terms of thickness and FD, the 1st premolar region had significantly higher values than the other regions (p < 0.05). In terms of density, the values in the right 1st molar and right 1st premolar regions were significantly higher (p < 0.05). The 1st premolar region is an ideal site for placement of palatal TADs. CBCT-assisted preliminary evaluation of FD value, bone density, and thickness may increase clinical success when selecting the location of TADs to be applied to the palatal bone.

Midpalatal Suture Maturation in Relation to Age, Sex, and Facial Skeletal Growth Patterns: A CBCT Study

BACKGROUND

The evaluation of midpalatal suture maturation is essential to undertake the most predictable maxillary expansion approach. Several factors, such as age, gender, and facial growth patterns, seem to be involved in midpalatal suture staging and, consequently, in its opening; however, the link between these variables and the stages of midpalatal suture development remains poorly understood. Our study aimed to analyse the midpalatal suture maturation in relation to age, sex, and skeletal growth patterns by CBCT.

METHODS

We enrolled 263 patients (119 males and 144 females) aged from 8 to 20 years. The midpalatal suture maturation was defined according to Angelieri et al.'s classification using a low-dose CBCT. The chi-square test and linear regression were applied to investigate the suture stages by age, sex, and vertical and sagittal growth patterns.

RESULTS

Stage A was present in 8- and 9-year-olds with a larger prevalence in boys, while the prevalence of stage E increased progressively with age. Stage D was the most prevalent in our sample. The statistical analysis described that stage A was more likely in the youngest subjects, and stage E in the oldest participants. The males tended to have lower maturation stages. Moreover, the hypodivergent and normodivergent subjects tended to have higher maturation stages, while Class III was more likely in subjects in stages D or E.

CONCLUSIONS

A total of 127 patients were in stages A, B, and C, showing an unfused suture. In young individuals, the opening of the midpalatal suture leads to a proper facial growth development by correcting the transverse superior hypoplasia. The midpalatal sutural maturation classification was related to age, sex, and divergence.

Successful treatment for an adult with bilateral posterior teeth crossbite by miniscrew-assisted rapid palatal expansion: A case report

Key Clinical Message

Successful treatment by miniscrew-assisted rapid expansion and clinical aligner therapy for an adult diagnosed with maxillary transverse deficiency (MTD) by clinical examinations and Yonsei transverse analysis.

Abstract

Adult orthodontic diagnosis and treatment with maxillary transverse deficiency (MTD) is challenging. Miniscrew-assisted rapid palatal expansion (MARPE) is a fast and low-risk method to expand the width of maxillary basal bone. This case report describes a 23-year-old female with mandible deviation and bilateral posterior teeth crossbite. She was diagnosed as MTD by the clinical examinations and Yonsei transverse analysis, and treated by the MARPE and clinical aligner therapy. After 26 months' treatment, cone-beam computed tomography (CBCT) images showed that the width of maxillary basal bone increased by 3.8 mm, that of zygomatic arch and nasal bone increased by 1.0 and 1.9 mm, respectively, and the bilateral posterior teeth crossbite was corrected. Furthermore, the dental midline of lower arch was consistent with that of upper arch and face, the molars arrived Angle Class II and canines was Class I relationships, the profile was maintained, the facial asymmetry was improved. The results of seventeen-month follow-up showed that the effect of orthodontic treatment is very stable. This case report demonstrates that MARPE is the effective approach for patients with MTD and facial asymmetry, which provide the alternative for the treatment of similar cases.

Midpalatal suture maturation in 15- to 35-year-olds: morphological assessment in the coronal plane using CBCT-an exploratory study

Rapid maxillary expansion (RME) is used in patients presenting transverse maxillary deficiency. However, RME may be unpredictable after late adolescence if the midpalatal sutural maturation stage (MPMS) is in late stage. Since MPMS evaluation is influenced by the expertise of the operator and image quality, this classification method could be complemented. Therefore, this study aimed to analyze the morphology of the midpalatal suture (MPS) and its surrounding bone in the coronal plane using cone beam computed tomography (CBCT) images of adolescents and young adults and to correlate the findings with their respective MPMS status. CBCT scans of 200 patients aged 15-35 years of both sexes were evaluated. MPS and surrounding bone tissue characteristics in the coronal and axial sections were analyzed, and MPMS was evaluated (A to E). Six categories were identified for the coronal evaluation, analyzing it in 2 standardized locations. Sutural morphology: I, hypodense sutural line limited by 2 hyper-dense para-sutural lines; II, hypodense sutural line; and III, suture not visible. The presence of para-sutural cancellous bone: CB0, compact bone; CB1, dense cancellous tissue; CB2, spaced cancellous bone. Midpalatal bone thickness (MBTh) was also measured. ANOVA-Bonferroni, chi-square, logistic regression and t-tests were used. MPMS increased with age. Sutural morphology I and CB0 bone were the most prevalent. Here we show that sutural morphology, para-sutural bone characteristics, and MPSM were significantly associated. The coronal evaluation of the MPS can complement the information from the MPSM assessment, allowing the identification of patent MPS even in the presence of late MPSM.

Dentoperiodontal and skeletal changes induced by miniscrew-assisted rapid maxillary expansion (C-expander) treatment in adults: A retrospective clinical trial

INTRODUCTION

The objective of this study was to evaluate the dental periodontal and skeletal response to ≥5 mm of expansion width achieved by C-expander treatment with posterior miniscrews placed between the first and second molars in adults.

METHODS

A total of 28 patients aged 21.91 ± 3.20 years with maxillary transverse deficiency underwent C-expander treatment. Anterior miniscrews were positioned between the first and second premolars, whereas posterior miniscrews were positioned between the first and second molars. Cone-beam computed tomography records were obtained before expansion and 3 months after expansion. The dental periodontal and skeletal changes for all patients were recorded.

RESULTS

The C-expander treatment expanded the palatal suture with slight buccal alveolar bone inclination. An increase in the nasal cavity width and a greater increase in the maxillary base bone width were observed after maxillary expansion. The expansion at the posterior nasal spine (3.78 mm) was approximately 85.7% of that at the anterior nasal spine (4.41 mm). No significant buccal dehiscence occurred after expansion, whereas the mesiobuccal alveolar bone thickness of the first molars was decreased at the 8 mm level with respect to the cementoenamel junction. The first molar showed decreased inclination (right, -0.45°; left, -0.38°, P >0.05), whereas the expansion at the apical level was less than that at the crown level. Age and the skeletal/dental expansion ratio had no discernible relationship.

CONCLUSIONS

Miniscrew-assisted C-expander treatment can be effective for adults with maxillary transverse deficiency. Rearward placement of the miniscrews may create an approximately parallel expansion. Most maxillary expansion was derived from skeletal expansion with slight alveolar bone buccal inclination.

Does Miniscrew-Assisted Rapid Palatal Expansion Influence Upper Airway in Adult Patients? A Scoping Review

(1) Objective: This scoping review evaluates the effects of miniscrew-assisted rapid palatal expansion (MARPE) on different regions of the upper airway in adult patients and investigates various methods of measurement. (2) Methods: The search encompassed Pubmed, Cochrane Library, Scopus and Web of Science. This review was conducted following the PRISMA_ScR guidelines, and the inclusion criteria for examined studies were chosen in accordance with the PICOS framework. (3) Results: Seven studies were included in this review, comprising four retrospective studies, one prospective and two case reports. All studies involved the use of Cone Beam Computed Tomography (CBCT) for measurements of the areas of interest. The percentage of increase in the volume of the nasal cavity varied between 31% and 9.9%, depending on the study. Volumetric variations in the nasopharynx were reported as increases between T0 (before expansion) and T1 (immediately after expansion) of 6.4%, 20.7% and 14.1%. All studies considered T0 before expansion and T1 immediately after expansion. Only one study evaluated remote follow-up to assess if the results were maintained after one year. (4) Conclusions: MARPE appears to lead to a statistically significant increase in the upper airway, especially in the nasal cavity and nasopharynx immediately after expansion. However, further prospective and retrospective trails with long-term controls are required to verify the effects of MARPE on the upper airway.

The effect of vertical skeletal proportions, skeletal maturation, and age on midpalatal suture maturation: a CBCT-based study

BACKGROUND

Midpalatal suture (MPS) maturation may be influenced by a range of parameters including age, gender, and vertical skeletal pattern. We therefore aimed to evaluate the effect of Frankfurt-mandibular angle (FMA), skeletal maturation, and age on the timing of MPS maturation.

METHODS

In this cross-sectional study, cone-beam computed tomography (CBCT) and lateral cephalograms were used to assess the MPS and cervical vertebral maturation (CVM) stage. A proportional odds logistic regression model was used to assess associations between age adjusted for gender and MPS maturation, and a regression analysis was performed to analyze the effect of vertical pattern on these associations.

RESULTS

A total of 201 patients (84 male and 117 female) with a mean age of 13.48 (SD 1.94) were included. With increasing age, the odds of belonging to a higher maturation stage increased (OR: 2.14; 95% CI 1.789; 2.567; P < 0.001); however, no association between FMA and MPS maturation was observed (OR: 1.01; 95% CI 0.964; 1.051; P = 0.76). A strong correlation between MPS maturation and CVM stage was not reported. Males had a higher probability of belonging to a lower MPS maturation stage (OR: 0.24; 95% CI 0.136; 0.415; P < 0.001).

CONCLUSIONS

Based on this cross-sectional analysis, midpalatal sutural maturation classification is associated with chronological age and occurs later in males. Neither CVM staging nor variation in vertical skeletal proportions were useful predictors of midpalatal maturation stage.

Convolutional neural network-assisted diagnosis of midpalatal suture maturation stage in cone-beam computed tomography

OBJECTIVES

The selection of treatment for maxillary expansion is closely related to the calcification degree of the midpalatal suture. A classification method for individual assessment of the morphology of midpalatal suture in cone-beam computed tomography (CBCT) is useful for evaluating the calcification degree. Currently, convolutional neural networks (CNNs) have been introduced into the field of oral and maxillofacial imaging diagnosis. This study validated the ability of CNN models in assessing the maturation stage of the midpalatal suture.

METHODS

The existing CNN model ResNet50 was trained to locate the CBCT transverse plane which contained a complete midpalatal suture. ResNet18, ResNet50, RessNet101, Inception-v3, and Efficientnetv2-s models were trained to evaluate the midpalatal suture maturation stage. Multi-class classification metrics, accuracy, recall, precision, F1-score, and area under the curve values from the receiver operating characteristic curve were used to evaluate the performance of the models, and gradient-weighted class activation map technology was utilised to visualise five midpalatal suture maturation stages for each model.

RESULTS

Resnet50 demonstrated an accuracy of 99.74 % in identifying the transverse plane that contained the complete midpalatal suture. The highest accuracies achieved on the two-stage, three-stage, and five-stage maturation classification tests were 95.15, 88.06, and 75.37 %, all of which exceeded the average accuracy of three experienced orthodontists.

CONCLUSIONS

The CNN model can locate the plane of the midpalatal suture in CBCT images and can assist clinicians in assessing the maturation stage of the midpalatal suture to select the means of maxillary expansion.

CLINICAL SIGNIFICANCE

The application of artificial intelligence on CBCT midpalatal suture plane localisation and maturation stage evaluation enhances diagnostic and treatment efficiency and accuracy of individual assessment of midpalatal suture calcification degree. Additionally, it assists the clinical palatal expansion technique in achieving ideal results.

An adult case of unilateral posterior crossbite caused by maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion

This report describes the successful treatment of an adult case of unilateral posterior crossbite caused by maxillary transverse deficiency with miniscrew-assisted rapid palatal expansion (MARPE). A female patient aged 35.5 years presented with masticatory disturbance, facial asymmetry, and unilateral posterior crossbite. She was diagnosed with unilateral posterior crossbite with a skeletal Class III jaw-base relationship and high mandibular plane angle. Her maxillary right and mandibular bilateral second premolars were congenitally absent, and the maxillary left second premolar was impacted. After the improvement of the posterior crossbite with MARPE, 0.018″ slot lingual brackets were placed on the maxillary and mandibular dentition. The total active treatment period was 22 months, and acceptable occlusion with a functional Class I relationship was achieved. Pretreatment and posttreatment cone-beam computed tomography images showed the disarticulation of the midpalatal suture after MARPE, and changes in the dental and nasomaxillary structures, nasal cavity, and pharyngeal airway. The case results demonstrate that MARPE produces greater skeletal expansion with minimal buccal tipping of the molars. MARPE may be effective for the treatment of maxillary transverse deficiency in adult patients.

Assessment of early dental arch growth modification with removable maxillary expansion by cone-beam computed tomography and lateral cephalometric radiographs: a retrospective study

BACKGROUND

This study evaluated the skeletal and dental changes of patients brought by early removable maxillary expansion (ERME) treatment to explore the clinical treatment effect of ERME on early dental arch growth modification.

METHODS

Subject children aged 6-10 years with a maxillary transverse deficiency received ERME treatment, cone-beam computed tomography (CBCT) and lateral cephalometric radiographs were measured before and after treatment, and statistical differences in the measured items were evaluated with corresponding statistical methods to explore the skeletal and dental changes.

RESULTS

After ERME treatment, there was a statistical increase in the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. A buccal inclination of the maxillary alveolar bone and a buccal inclination and buccal movement in the alveolar bone of maxillary first molars were found. The maxillary skeletal expansion was statistically greater than the dental expansion. Increases in the mandibular alveolar bone arch width and dental arch width happened after treatment. A decrease in angle ANB and an increase in Ptm-A, U1-SN, U1-PP, L1-MP, and L6-MP were found after treatment. No statistical changes in the growth pattern-related measured items were observed.

CONCLUSIONS

ERME could expand the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. The maxillary skeletal expansion was greater than the dental expansion. Secondary increases in the mandibular alveolar bone and dental arch widths would happen after ERME. ERME would result in a mandibular advancement, a labial inclination of maxillary anterior teeth, and an increase of maxillary sagittal length, and would not change the patient's growth pattern.

TRIAL REGISTRATION

This study was approved by the Institutional Review Board of the West China Hospital of Stomatology, Sichuan University. (WCHSIRB-D-2020-446).

Finite element analysis of the influence of interdigitation pattern and collagen fibers on the mechanical behavior of the midpalatal suture

The midpalatal suture (MPS) corresponds to the tissue that joins the two maxillary bones. Understanding the mechanical behavior of this tissue is of particular interest to those patients who require orthodontic treatments such as Rapid Maxillary Expansion (RME). The objective of this research was to observe the influence of interdigitation and collagen fibers on the mechanical response of MPS. To this end, a finite element analysis in two-dimensional models of the bone-suture-bone interface was performed considering the characteristics of the MPS. The geometry of the suture was modeled with 4 different levels of interdigitation: null, moderate, scalloped and fractal. The influence of collagen fibers, aligned transversely along the suture, was considered by incorporating linked structures of the bone fronts. According to the results, the factor that has the greatest impact on the magnitude and distribution of stresses is the interdigitation degree. A higher level of interdigitation produces an increase in tissue stiffness and a lower influence of collagen fibers on the mechanical response of the tissue. Therefore, this research contributes to the understanding of the MPS biomechanics by providing information that may be useful to health staff when evaluating the feasibility of procedures such as RME.

External root resorption and rapid maxillary expansion in the short-term: a CBCT comparative study between tooth-borne and bone-borne appliances, using 3D imaging digital technology

BACKGROUND

The aim of the study was to analyze and compare external root resorption (ERR) in patients treated with tooth-borne (TB) and bone-borne (BB) rapid maxillary expansion (RME).

METHODS

The sample included 40 subjects who received tooth-borne RME (TB group, average age: 13.1 ± 1.08 years) or bone-borne RME (BB group, average age: 14.5 ± 1.11 years) and Cone-beam computed tomography (CBCT) scans before treatment (T0) and after 3-month of retention (T1). A specific 3D Imaging technology was used to generate 3D models of posterior dentition (M1 = maxillary first molars, P2 = second premolars, P1 = first premolar) and calculate volumetric data (mean and percentage values) and shape changes, the latter obtained from deviation analysis between the radicular models at different time points. Evaluation of radicular length changes was performed for each tooth. Data were statistically analysed to perform intra-timing and inter-groups comparisons.

RESULTS

A significant reduction of radicular volume and length was found in posterior dentition in both groups (p < 0.05), and the M1 (volume) and its palatal root (length) were mostly involved in this response. No differences were found between M1, P1 and P2 (p > 0.05) when volumetric changes were calculated as percentage of the total volume. Deviation analysis revealed that the radicular areas mostly affected by shape change were the apex and bucco-medial side. The amount of ERR was significantly greater in TB group compared to BB group.

CONCLUSIONS

BB-RME treatment could reduce the amount of ERR at the post-expansion 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.

Three-dimensional micromorphology of human midpalatal suture and pterygomaxillary articular complex

BACKGROUND

Sutures exist in the craniofacial area, and the pattern of maturation and synostosis of facial sutures is largely unknown.

METHODS

For a comprehensive understanding of the three-dimensional circummaxillary suture micromorphology, human midpalatal suture (MPS) and pterygomaxillary articular complex from eight subjects' (five males, three females, 72-88 years old) autopsies were longitudinally scanned with microcomputed tomography. Additional histology was performed for hematoxylin and eosin staining. Sutural micromorphology was assessed by interdigitation index (II), obliteration index (OI) and obliteration number. Intergroup comparisons were performed with Kruskal-Wallis and Mann-Whitney U with Bonferroni correction (α = 0.005). Correlation with anteroposterior and craniocaudal gradients was assessed with Spearman's correlation test (α = 0.05).

RESULTS

Maxillary region of MPS presented a higher II 1.50 (0.61) and obliteration number per slice 8 (9) (P < 0.005). OI was increased in palatomaxillary 35% (47%) followed by pterygopalatine suture 25% (49%) (P < 0.005). The II and OI of the MPS exhibited only a weak anteroposterior gradient, with relatively low correlations. Obliteration areas were found sporadically along the entire MPS.

CONCLUSIONS

Based on these findings, it is conceivable that the success of nonsurgical maxillary expansion largely depends on individual variations in sutural morphology and maturation rather than appliance design.

Pain during Rapid Maxillary Expansion: A Systematic Review

Aim: The aim of the present systematic review is to evaluate the pain perceived by patients during rapid maxillary expansion (RME) in relation to factors such as demographic characteristics, appliance type, activation protocol, and the eventual use of medication or pain management strategies. Materials and methods: An electronic search of available articles on the subject was conducted on three electronic databases, using predefined keywords. Sequential screenings based on pre-established eligibility criteria were performed. Results: Ten studies were ultimately included in this systematic review. The main data of the reviewed studies were extracted according to the PICOS approach. Conclusions: Pain is a common effect of RME treatment that tends to decrease over time. Gender and age differences in pain perception are not clear. Perceived pain is influenced by the expander design and expansion protocol used. Some pain management strategies can be useful for reducing RME-associated pain.

Comparison between Two Methods of Skeletal Growth Evaluation: Cervical Vertebrae Maturations and Middle Phalanx Maturation

Aim

Growth measurement has always been essential to identify the best time to employ orthopedic or orthodontic appliances. Optimal timing for orthodontic treatment is strictly linked to the identification of periods of craniofacial growth when treatment is more effective.The aim of this study was to compare two different methods, middle phalanx maturation (MPM) and cervical vertebrae maturation (CVM), used to evaluate the stage of facial growth.

Materials and methods

The research data was collected from July 2018 to April 2019 at the Dental Clinic of the San Gerardo Hospital in Monza. The study included a sample of 98 patients-46 males and 52 females. For each patient, a latero-lateral teleradiography of the skull and an X-ray on the middle finger of the right hand were obtained.The statistical analysis of the comparison of the stages of skeletal maturation obtained by the MPM and CVM methods was performed using the correlation coefficient for ranks of Spearman.

Results

A descriptive statistical analysis of the entire sample of 98 patients was performed (mean age of 12.2 years and median of 12.2 years). The average age of females in every single stage of MPM was significantly lower than the average age of males. Of the total sample, 87 patients (88.8%) showed complete agreement between the two methods.

Conclusion

The results obtained from the statistical analysis of this study allowed us to confirm a satisfactory agreement between the two methods.The intermediate phalanx method is a valid and alternative indicator to CVM for the identification of the puberty growth peak. We can, therefore, consider the MPM method a valid indicator of skeletal maturity.

How to cite this article

Mirabelli L, Bianco E, Pigato G, et al. Comparison between Two Methods of Skeletal Growth Evaluation: Cervical Vertebrae Maturations and Middle Phalanx Maturation. Int J Clin Pediatr Dent 2023;16(2):327-332.

Changing the topographical anatomy among the maxilla, palatine bone, and greater palatine nerve: a histological study using human fetuses

PURPOSE

The palatine bone (PAL) rides over the maxilla (MX) without an end-to-end suture in the bony palate of fetuses. However, changes in the topographical relationship among bones was unknown at and along the pterygopalatomaxillary suture, including the palatine canals.

METHODS

Using sagittal, frontal, and horizontal histological sections of the head from 15 midterm fetuses to 12 near-term fetuses, we depicted the changes in the topographical anatomy of the MX, PAL, and greater palatine nerve (GPN).

RESULTS

In the bony greater palatine canal of these fetuses, the medial and posterior walls facing the GPN were consistently made up of the PAL. At midterm, the entire course of the GPN was embedded in the PAL (six fetuses), or the MX contributed to the lateral wall of the nerve canal (nine). At near-term, the anterior and lateral walls showed individual variations: an MX in the anterior and lateral walls (three fetuses), an anterior MX and a lateral PAL (five), an anterior PAL and a lateral MX (two), and a PAL surrounding the GPN (four).

CONCLUSION

These increasing variations suggested that the pterygopalatomaxillary suture was actually growing and that the PAL transiently expanded anteriorly and/or laterally to push the MX in fetuses. The "usual" morphology in which the GPN is sandwiched by the MX and PAL is likely established after birth, possibly during adolescence. The driving force of this change may not be produced by the masticatory apparatus. Rather, it might be triggered by the growing maxillary sinus.

Palatal surface development from 6 years of age to early adulthood: data modelling using 3D geometric morphometrics

OBJECTIVES

The study followed the modelling of postnatal growth of a healthy palate of the Central European (Czech) population sample based on transverse data on sex and age from 6 to 19 years.

MATERIALS AND METHODS

Digitised 3D models of 212 healthy palatal surfaces were evaluated using 3D geometric morphometrics and superimpositions. The individuals were grouped based on age (preschool, younger and older school age, younger and older adolescents, young adults) and sex (♂ n = 101, ♀ n = 111).

RESULTS

Female palatal development was non-linear and was interrupted between the 10-12 years and then proceeded intensively until the age of 15 when it ceased. In contrast, male-modelled growth was consistent throughout the follow-up and continued linearly until at least 19 years of age. The palate did not widen further with increasing age, and primarily palatal vaulting and heightening were found. The characteristics and distribution of areas with extensive modelled growth changes were comparable in females and males, as confirmed by the location of principal components (PC1 and PC2) within modal space and growth trajectories. The extent of sexual dimorphism increased from 15 years of age due to pubertal spurt combined with earlier completion of palatal development in females.

CONCLUSIONS

The study showed modelled healthy palatal development from 6 years of age to early adulthood, which might be utilised as reference standards for the Central European population sample.

CLINICAL RELEVANCE

The comparison of normal reference subjects with patients with cranio-maxillo-facial dysmorphologies represents the first step in diagnosing and establishing effective therapy.

Nasal Septum Changes in Adolescents Treated with Tooth-Borne and Bone-Borne Rapid Maxillary Expansion: A CBCT Retrospective Study Using Skeletal Tortuosity Ratio and Deviation Analysis

Background: Using three-dimensional (3D) images, this study evaluated the impact of Rapid Maxillary Expansion (RME) on changes in Nasal Septal Deviation (NSD). Methods: Cone-beam computed tomography (CBCT) scan of 40 children with transverse maxillary deficiency, who received tooth-borne (TB) RME or bone-borne (BB) RME, were included in this investigation. Two CBCT scans were performed: one before to appliance installation (T0) and one after a 6-month retention period (T1). The analysis was performed by dividing the actual length of the septum by the desired length in the mid-sagittal plane to measure NSD based on the tortuosity ratio (TR). Results: Subjects in the TB group showed a statistically significant reduction (p < 0.05) of the TR value from T0 to T1, according to the paired Student t test. Subjects in the BB group showed similar findings, with a statistically significant reduction (p < 0.05) of the TR value from T0. No statistically significant differences were found between the mean changes of TR between TB group and BB group. Conclusions: RME may have some effects in reducing the degree of NSD; however, no differences were found between RME performed with TB and BB anchorage systems.

Analysis of the Frequency and Correlated Factors of Midpalatal Suture Maturation Stages in Young Adults, Based on Cone Beam Computed Tomography Imaging

BACKGROUND

The choice of whether to perform a palatal disjunction in constricted maxilla has traditionally been decided based on the age of the patients, although there are gradually increasing references to the fact that this is not a determining factor. The main goal of this study was to evaluate the frequency of the different stages of midpalatal suture maturation in a sample of young adults between 15 and 30 years of age. Other objectives also included analyzing the possible correlation the maturation stages could maintain with sex and age groups.

METHODS

142 Cone Beam Computed Tomography (CBCT) scans of young adults were performed. The images were divided into four age groups based on age ranges of 15-18, 19-22, 23-26, and 27-30 years. Each group consisted of 26, 41, 39, and 36 patients, respectively, which were classified using Angelieri's method. In addition, sex and age groups were considered as variables, and the possible correlation of the prevalence of each one, according to age and sex, was studied.

RESULTS

the sample was classified into 4.9% stage B; 52.1% stage C; 27.5% stage D; and 15.5% stage E. In addition, no statistically significant correlation between sex and the maturation stages was found, but more advanced stages did appear to be related to the chronological age of the subjects.

CONCLUSIONS

The frequency of maturational stages where the suture is shown to be consolidated did not appear to be as high as expected; therefore, the idea of rejecting transverse plane treatment in a conventional manner in an out-of-growth patient should be discarded.

Midpalatal Suture: Single-Cell RNA-Seq Reveals Intramembrane Ossification and Piezo2 Chondrogenic Mesenchymal Cell Involvement

The midpalatal suture is mainly responsible for the growth and development of the maxillary and resistance to rapid maxillary expansion (RME). It is essential for clinical researchers to explore the intramembrane ossification and to elucidate the underlying mechanism of the maturation and ossification process of the midpalatal suture to help identify the optimum time and force of RME. However, mechanistic studies associated with the midpalatal suture are rare. The aim of this present study is to create an intramembrane osteogenesis model for the midpalatal suture region of mice. Interestingly, we discovered a type of chondrogenic mesenchymal cell expressing Piezo2, which might be related to the detection of mechanical and external stimuli. This result provides a potential molecular and cellular mechanism that explains why the midpalatal suture is not closed until adulthood. We depict a landscape of mesenchymal cells that might play an important role in the intramembrane osteogenesis of the midpalatal suture and provide new perspectives on midpalate suture maturation and ossification, which might lead to further possibilities for clinical operations.

Non-Surgical Transversal Dentoalveolar Compensation with Completely Customized Lingual Appliances versus Surgically Assisted Rapid Palatal Expansion in Adults-The Amount of Posterior Crossbite Correction

The aim of this study was to compare the crossbite correction of a group (n = 43; f/m 19/24; mean age 27.6 ± 9.5 years) with surgically assisted rapid palatal expansion (SARPE) versus a non-surgical transversal dentoalveolar compensation (DC) group (n = 38; f/m 25/13; mean age 30.4 ± 12.9 years) with completely customized lingual appliances (CCLA). Arch width was measured on digital models at the canines (C), second premolars (P2), first molars (M1) and second molars (M2). Measurements were obtained before treatment (T0) and at the end of lingual treatment (T1) or after orthodontic alignment prior to a second surgical intervention for three-dimensional bite correction. There was no statistically significant difference (p > 0.05) in the amount of total crossbite correction between the SARPE and DC-CCLA group at C, P2, M1 and M2. Maxillary expansion was greater in the SARPE group and mandibular compression was greater in the DC-CCLA group. Crossbite correction in the DC-CCLA group was mainly a combination of maxillary expansion and mandibular compression. Dentoalveolar compensation with CCLAs as a combination of maxillary expansion and mandibular compression seems to be a clinically effective procedure to correct a transverse maxillo-mandibular discrepancy without the need for surgical assistance.

Age-dependent interactions of maxillary sutures during RME and their effects on palatal morphology : CBCT and dental cast analysis

PURPOSE

The effects of rapid maxillary expansion (RME) on the transverse palatine and midfacial sutures have been extensively scrutinized. Unlike the dentition stage, age-dependency was not yet regarded when investigating morphological changes of the tooth-bearing palate. Therefore, the first aim of the present study was to analyse age-dependent sutural and morphological changes of the palate in selected patients by cone-beam computed tomography (CBCT) and dental cast analysis. Secondly, age-dependent effects of RME on width, height, and depth of the palate in the region of the maxillary palatine processes were investigated by a comprehensive dental cast study, so that the combination of results could be used to provide a biomechanical explanation of the occurring changes.

METHODS

CBCT datasets of 9 patients (between 7.3 and 13.8 years) were measured around the median palatal suture and compared with the results of an individualised dental cast analysis. In addition, possible effects on other maxillary sutures were investigated. In the dental cast study, changes after RME in the tooth-bearing palate were analysed three-dimensionally in 60 children and adolescents. It was possible to divide those into three equally sized, age-dependant groups (PG1: < 10 years, n = 20; PG2: ≥ 10 < 12 years, n = 20; PG3: ≥ 12 years, n = 20).

RESULTS

The CBCT analysis reveals age-related differences in sutural responses. The opening width of the median palatine suture decreases cranially (frontal) and dorsally (horizontal). The opening mode thus changes from parallel to triangular in both planes. The transverse palatine suture completely opens in younger patients only (PG1 and PG2). The width increases are always significant in all patients. While in PG1 the width increase is greater posteriorly than anteriorly, this is always reversed in PG2 and PG3. The palatal height always increases significantly anteriorly, but posteriorly only in the youngest patients (PG 1) median and paramedian. In PG 2 and PG 3, the posterior height change is very small. That is the reason why the anteroposterior comparison reveals a much more pronounced height increase anteriorly than posteriorly.

CONCLUSION

The comparison of selected CBCT data with a dental cast analysis allows the conclusion that the maxillary expansion after RME in children up to 10 years is rather parallel, whereas it occurs V‑shaped (anterior > posterior transversal, inferior > superior vertical) with increasing age, especially in adolescents from the age of 12. In addition to an age-progressive rigidity of the pterygopalatomaxillary junction, morphological changes of the transverse palatine suture during growth seem to be causal. Thus, age-dependent effects of palatal expansion occur due to a positional change of maxillary centres of rotation and resistance. From dental cast measurements, especially at the skeletal-basal level, conclusions can be drawn about the median palatal suture opening mode.

Fractal Perspective on the Rapid Maxillary Expansion Treatment; Evaluation of the Relationship Between Midpalatal Suture Opening and Dental Effects

OBJECTIVE

This retrospective study investigates the relationship between the midpalatal suture opening and the dental effects of Rapid Maxillary Expansion (RME) treatment using fractal analysis.

METHODS

The participants of this study were selected from the patients who underwent Cone Beam Computed Tomography(CBCT) scans in 2019 and were treated with banded type Maxillary Expander. This study included 20 participants (with a mean age of 10.64±10.64, ranging from 8 to 13 years): 12 males and 8 females. Patients went through CBCT scan and images taken were analyzed using the ImageJ program. The following parameters were measured and analyzed before and after RME treatment: fractal dimensional value of Midpalatal suture(MPS), Distobuccal(DB), Mesiobuccal(MB), Palatal(P), Total distance, Cortical bone and linear values of External maxilla, Internal maxilla, Palatal roots, distance of Central fosses and angular values of Tipping value of 16 and 26. We used Spearman's nonparametric test for non-normal variables to investigate the correlation between changes in MPS and other variables.

RESULTS

The results showed a strong positive correlation between the MPS and Right MB (0.34, p<0.05) and Left MB (0.59, p<0.05) variables and a strong negative correlation between the MPS and the External maxillary variables (-0.53, p<0.05).

CONCLUSION

The results of the study have shown a strong correlation between right and left MB and External Maxilla. RME caused a reduction in buccal alveolar bone thickness and a slight reduction in MPS thickness in growing patients. Therefore, we suggest that fractal analysis can be used to evaluate the skeletal and dental effects of RME in patients.

Management of Class III Malocclusion and Maxillary Transverse Deficiency with Microimplant-Assisted Rapid Palatal Expansion (MARPE): A Case Report

Microimplant-assisted rapid palatal expansion (MARPE) has been demonstrated successfully in maxillary expansion in late adolescence and adulthood. The maxillary advancement accompanied by expansion is frequently anticipated, which is beneficial for the treatment of class III malocclusion. Airway volume increase can also be noted in some cases from the measurement of cone beam computerized tomography (CBCT) after expansion. The objective of this case report is to demonstrate the feasibility of applying MARPE on late adolescence patients with maxillary transverse deficiency and to present the changes in transverse and anteroposterior dimensions as well as the volume increase in velopharyngeal airway after MARPE. A 15-year-old female presented class III skeletal pattern. She had maxillary transverse deficiency with moderate crowding and posterior/anterior crossbites. Maxillary Skeletal Expander (MSE; Biomaterials Korea Inc.) type-2 was used as a MARPE device in this case. After four weeks of maxillary expansion, a significant amount of expansion was achieved and the anterior crossbite was spontaneously corrected. Fixed appliance treatment was commenced four weeks after MARPE with 0.022-slot preadjusted brackets (MBT prescription). Temporary anchorage devices (TADs) were placed over the mandibular buccal shelves for posterior teeth distalization and crowding relief. After 25 months of treatment, the facial profile was improved with maxillary advancement (SNA: 83° to 83.5°) and mandibular backward rotation (SNB: 83° to 82°; SN-MP: 34.5° to 35°). In this case, MARPE not only engenders significant transverse correction but also aids in anteroposterior change. The treatment effects of maxillary advancement and mandibular backward rotation can lead to a more esthetic profile in skeletal class III cases.

The impact of mini-implant hybrid hyrax maxillary expansion on pulp blood flow and sensibility in healthy and traumatized teeth: A prospective study

INTRODUCTION

We aimed to assess pulp blood flow (PBF) and pulp sensibility changes in healthy and traumatized teeth undergoing maxillary expansion with a mini-implant hybrid hyrax appliance.

METHODS

Forty-five patients requiring maxillary expansion either with mini-implant supported hyrax expander (MARME) or tooth-borne hyrax expander (RME) had the pulp status of their maxillary anterior teeth assessed using laser Doppler flowmetry, electric pulp testing, and thermal testing (carbon dioxide snow). The study cohort was divided into 4 groups on the basis of expansion appliance (MARME or RME) and trauma experience (trauma or nontrauma). Each patient was tested before expansion, 2 weeks after expansion, and 3 months after expansion (T3). Relationships between PBF, time interval, and trauma were evaluated using linear mixed modeling.

RESULTS

Healthy teeth with RME or MARME expansion had reestablished pretreatment PBF at T3 (P >0.05). Traumatized teeth undergoing RME did not reach pretreatment PBF at T3 (P ≤0.05). There were no statistically significant changes in PBF in the MARME+Trauma group at all time intervals (P >0.05). A reduction in pulp blood flow occurred during rapid maxillary expansion from both expansion appliances; however, the relative reduction of PBF in MARME was less than with RME (P ≤0.05) 2 weeks after expansion. Most teeth across all groups (≥85%) maintained pulp sensibility at all time intervals regardless of whether there was a history of trauma.

CONCLUSIONS

Patients with transverse discrepancies and a history of trauma may benefit from MARME as evidenced by reduced changes in PBF compared with RME without affecting pulp sensibility.

Age, Sex, and Maxillary Position Are Associated with Successful Microimplant-Assisted Rapid Palatal Expansion in Adults

The purpose of this study was to investigate the possible predictors of success of microimplant-assisted rapid palatal expansion (MARPE) in skeletally mature patients. Additionally, factors associated with the amount of maxillary expansion were analyzed. Factors associated with MARPE success were analyzed in 53 adult patients (27 males, 26 females, mean age 25.8 ± 8.9 years, and range 18.0 to 56.6 years) who had a maxillary transverse deficiency greater than 2 mm and a cervical vertebral maturation stage of 6. Age at pretreatment (T1), sex, sutural bone density at T1, type of appliance, mode of microimplant fixation, and lateral cephalometric variables at T1 were considered for inclusion as predictors for MARPE success. In patients who showed successful maxillary skeletal expansion, the linear distances of maxillary widths were measured on cone-beam-computed-tomography images at T1 and after MARPE (T2), and factors associated with the amount of expansion were analyzed. In total, 41 of the 53 patients showed successful maxillary expansion. Age (p = 0.019), sex (p = 0.002), and A-N perp (p = 0.015) were significantly associated with the success of MARPE. The factors associated with the amount of maxillary skeletal expansion were SN-MP and midpalatal-suture density at T1. In conclusion, there is a greater chance of failure in male patients who are older and have maxillary retrusion. A greater amount of maxillary expansion can be expected in patients with a higher mandibular-plane angle and with lower midpalatal-suture density.

Midpalatal Suture CBCT Image Quantitive Characteristics Analysis Based on Machine Learning Algorithm Construction and Optimization

Background: Midpalatal suture maturation and ossification status is the basis for appraising maxillary transverse developmental status. Methods: We established a midpalatal suture cone-beam computed tomography (CBCT) normalized database of the growth population, including 1006 CBCT files from 690 participants younger than 24 years old. The midpalatal suture region of interest (ROI) labeling was completed by two experienced clinical experts. The CBCT image fusion algorithm and image texture feature analysis algorithm were constructed and optimized. The age range prediction convolutional neural network (CNN) was conducted and tested. Results: The midpalatal suture fusion images contain complete semantic information for appraising midpalatal suture maturation and ossification status during the fast growth and development period. Correlation and homogeneity are the two texture features with the strongest relevance to chronological age. The overall performance of the age range prediction CNN model is satisfactory, especially in the 4 to 10 years range and the 17 to 23 years range, while for the 13 to 14 years range, the model performance is compromised. Conclusions: The image fusion algorithm can help show the overall perspective of the midpalatal suture in one fused image effectively. Furthermore, clinical decisions for maxillary transverse deficiency should be appraised by midpalatal suture image features directly rather than by age, especially in the 13 to 14 years range.

Rapid Maxillary Expansion on the Adolescent Patient: Systematic Review and Case Report

Aim: In the literature, many studies and articles are investigating new devices and approaches to achieve rapid palate expansion through the opening of the palatal suture, and evaluating the skeletal, dental, and soft tissue effects. The purpose of this review was to assess how palatal expansion is performed in adolescent patients with permanent dentition. Furthermore, it was reported as an example of successful orthodontic treatment of an 11-year-old female patient affected by maxillary skeletal transverse deficiency, in permanent dentition. Methods: A search of the literature was conducted on PubMed, Cochrane, Scopus, Embase, and Web of Science databases. Inclusion criteria were the year of publication between 2017 and 2022, patients aged 10 to 16 years in permanent dentition, with transversal discrepancy, treated with tooth-borne, bone-borne, hybrid palatal expanders. Results: A total of 619 articles were identified by the electronic search, and finally, a total of 16 papers were included in the qualitative analysis. Conclusions: From this study, it was assessed that MARPE is more predictable, and it determines a more significant expansion of the suture than the Hyrax expander, with fewer side effects.

Salivary oxidative stress during and after rapid maxillary expansion

Objectives:

The objectives of the study were to evaluate oxidative stress biomarkers during a rapid maxillary expansion (RME).

Material and Methods:

Fourteen patients were treated with an acrylic RME device, and after treatment, all were followed for 3 months. Saliva samples were collected before activation (baseline), 1st, 10th days after the first activation, and after retention. Periodontal indexes were recorded at baseline and after retention. Nitric oxide (NO) and malondialdehyde (MDA) levels were evaluated.

Results:

NO levels were elevated on the 10th day compared to baseline (P < 0.01), revealing a decrease after retention (P < 0.01). MDA levels were increased on the 10th day and after retention periods compared to baseline (P < 0.01, respectively). Both plaque and gingival indexes increased after retention relative to baseline (P < 0.01, respectively).

Conclusion:

Initial stages of orthopedic force increased salivary oxidative stress biomarkers. Long-term results showed decreased levels of NO, but still high MDA levels. The initially increased NO expression decreased after retention, despite the increase in microbial load at this period which might show the effect of mechanical stimuli to be more effective than the microbial load. MDA levels remained at high levels during the post-retention period, arising a possible consideration for the impact of material properties or deficiencies of oral hygiene. Future long-term evaluations for oxidative stress status and orthodontic appliances would be useful.

Techniques for Bone Assessment and Characterization: Porcine Hard Palate Case Study

The hard palate plate has an important structural function that separates the nasal cavity and the nasopharynx. Incomplete regeneration of palatal fistulae in children with a cleft palate deformity after primary palatoplasty is a relatively common complication. To date, the information about the physicochemical bone features of this region is deficient, due to the low availability of human samples. Swine and human bone share anatomical similarities. Specifically, pig bones are widely used as experimental animal models in dental, orthopedic, or surgical techniques. The aim of this study was to show different techniques to evaluate and characterize alternative properties of pig hard palate bone, compared to commercial hydroxyapatite, one of the most used biomaterials for bone tissue regeneration. Chemical analyses by Energy dispersive spectroscopy (EDS) and X-ray fluorescence (XRF) showed calcium and phosphate ions as the main constituents of bone, while magnesium, iron, sodium, potassium, and zinc ions were minor constituents. The calcium phosphate molar ratio (Ca/P) in the bone was low (1.1 ± 0.2) due to the very young specimen sample used. The FTIR spectrum shows the presence of phosphates ions (PO₄^3-) and the main characteristics of collagen type I. The XRD results showed that the hard palate bone has a mixture of calcium, octacalcium dihydrogen phosphate (OCP), and apatite, where OCP is the predominant phase. Besides, this research demonstrated that the young bone has low crystallinity and small crystal size compared with commercial hydroxyapatite (HA). The palatine process of maxilla density and porosity data reported, suggest that the palate bone is getting closer to the compact bone with a 52.78 ± 2.91% porosity and their mechanical properties depend on the preparation conditions and the area of the bone analyzed.

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.

Skeletal and alveolar changes in conventional rapid palatal expansion (RPE) and miniscrew-assisted RPE (MARPE): a prospective randomized clinical trial using low-dose CBCT

Background

This prospective randomized clinical trial aimed to evaluate the immediate and short-term skeletal, dentoalveolar, and periodontal effects of rapid palatal expansion (RPE) and miniscrew-assisted RPE (MARPE) in adolescent and young adult patients.

Methods

This study followed a two-arm, parallel, randomized clinical trial design that recruited patients with transverse maxillary deficiency in a 1:1 allocation ratio. Forty patients (14 men and 26 women) requiring maxillary expansion were randomly allocated to the RPE (n = 20, age = 14.0 ± 4.5) or MARPE (n = 20, age = 14.1 ± 4.2) groups. The assignment was performed via computer-generated block randomization, with a block size of four. Upon identical (35 turns) amount of expansion, low-dose cone-beam computed tomography images were taken before treatment (T0), immediately after expansion (T1), and after a 3-month consolidation period (T2). The primary outcome of this study comprised the assessment of midpalatal suture separation. Secondary outcomes included, skeletal, dentoalveolar, and periodontal measurements, which were performed at each time point.

Results

The frequency of midpalatal suture separation was 90% (18/20) and 95% (19/20) for the RPE and MARPE groups, respectively. A greater increase in nasal width in the molar region (M-NW) and greater palatine foramen (GPF) was observed immediately after the expansion (T1-T0) and consolidation periods (T2-T0) in the MARPE group compared to the RPE group (P < 0.05). The MARPE and RPE groups showed similar dentoalveolar changes except for the maxillary width (PM-MW, M-MW). The MARPE group presented greater bilateral first premolar (PM-MW) and molar (M-MW) maxillary width in relation to the RPE group (P < 0.05). Through the expansion and consolidation periods (T2-T0), lesser buccal displacement of the anchor teeth was observed in the MARPE group (PM-BBPT, PM-PBPT, M-BBPT [mesial and distal roots], and M-PBPT)( P < 0.05).

Conclusions

Midpalatal suture separation was observed in 90% and 95% of patients in the RPE and MARPE groups, respectively. Both RPE and MARPE groups exhibited significant triangular basal bone expansion and skeletal relapse during consolidation. Under identical amounts of expansion, the MARPE group showed lower decrease in the skeletal, dentoalveolar and periodontal variables after consolidation. The reinforcement of RPE with miniscrews contributes to the maintenance of the basal bone during consolidation period.

Trial registration WHO Institutional Clinical Trials Registry Platform (IRB No. KCT0006871 / Registration date 27/12/2021).

Short-Term and Long-Term Changes of Nasal Soft Tissue after Rapid Maxillary Expansion (RME) with Tooth-Borne and Bone-Borne Devices. A CBCT Retrospective Study

The objective of the study was to assess the changes in nasal soft tissues after RME was performed with tooth-borne (TB) and bone-borne (BB) appliances. Methods. This study included 40 subjects with a diagnosis of posterior cross-bite who received tooth-borne RME (TB, average age: 11.75 ± 1.13 years) or bone-borne RME (BB, average age: 12.68 ± 1.31 years). Cone-beam computed tomography (CBCT) was taken before treatment (T0), after a 6-month retention period (T1), and one year after retention (T2). Specific linear measurements of the skeletal components and of the soft-tissue region of the nose were performed. All data were statistically analyzed. Results. Concerning skeletal measurements, the BB group showed a greater skeletal expansion of the anterior and posterior region of the nose compared to the TB group (p < 0.05) immediately after RME. Both TB and BB RME induce a small increment (>1 mm) of the alar base and alar width, without significant differences between the two expansion methods (p > 0.05). A high correlation was found between skeletal and soft-tissue expansion in the TB group; instead, a weaker correlation was found in the BB group. Conclusion. A similar slight increment of the alar width and alar base width was found in both TB and BB groups. However, the clinical relevance of these differences, in terms of facial appearance, remains questionable.