Palatal Expansion Research Articles

Effects of mini-implant assisted rapid palatal expansion on the deviated nasal septum and inferior nasal meatus: A CBCT study

Objective: The purpose of this study was to evaluate the effects of the mini-implant assisted rapid palatal expansion on the nasal septum and the inferior nasal meatus (INM) in the patients with nasal septal deviation. Methods: The CBCT images were taken before (T0), after (T1), and more than 5 months after (T2) MARPE in 17 patients who had NSD. According to the direction of the NSD, the concave side was set as group 1 and the convex side was set as group 2 by patient. The volume of the INM, nasal septal tortuosity ratio were calculated. Also, to evaluate 3-dimensional changes of the nasal septum, distance between C point (The junction of perpendicular plate of ethmoid bone and vomer) and three vertical planes were calculated. And distance between C point and lateral wall of nasal cavity was measured. Results: The total volume of the INM increased significantly after MARPE (p < 0.001). The distance from the C point to the vertical plane increased significantly after MARPE (p < 0.01). Also, there was a significant difference between the groups in the distance between the C point and the lateral wall of nasal cavity (p < 0.001) before and after treatment. But there was no significant difference in the increase ratio. Conclusion: After MARPE, the volume of INM was significantly increased. The nasal septum was more displaced to the deviated side without a significant morphological change. But the increase ratio of both group was similar.

Three-Dimensional Evaluation Effects of Microimplant-Assisted Rapid Palatal Expansion on the Upper Airway Volume: A Systematic Review and Meta-Analysis

Microimplant-assisted rapid palatal expansion is increasingly used clinically; however, the effect on the upper airway volume in patients with maxillary transverse deficiency has not been thoroughly evaluated yet. The following electronic databases were searched up to August 2022: Medline via Ovid, Scopus, Embase, Web of Science, Cochrane Library, Google Scholar, and ProQuest. The reference lists of related articles were also reviewed by manual search. The Revised Cochrane Risk of Bias Tool for randomized trials (ROB2) and the Risk of Bias in non-randomized Studies of Interventions (ROBINS-I) tool were used to evaluate the risks of bias of the included studies. The mean differences (MD) and 95% confidence intervals (CI) of changes in nasal cavity and upper airway volume were analyzed using a random-effects model, and subgroup and sensitivity analyses were also performed. Two reviewers independently completed the process of screening studies, extracting data, and assessing the quality of studies. In total, twenty-one studies met the inclusion criteria. After assessing the full texts, only thirteen studies were included, with nine studies selected for quantitative synthesis. Oropharynx volume increased significantly after immediate expansion (WMD: 3156.84; 95% CI: 83.63, 6230.06); however, there was no significant change in nasal volume (WMD: 2527.23; 95% CI: -92.53, 5147.00) and nasopharynx volume (WMD: 1138.29; 95% CI: -52.04, 2328.61). After retention a period, significant increases were found in nasal volume (WMD: 3646.27; 95% CI: 1082.77, 6209.77) and nasopharynx volume (WMD: 1021.10; 95% CI: 597.11, 1445.08). However, there was no significant change after retention in oropharynx volume (WMD: 789.26; 95% CI: -171.25, 1749.76), palatopharynx volume (WMD: 795.13; 95% CI: -583.97, 2174.22), glossopharynx volume (WMD: 184.50; 95% CI: -1745.97, 2114.96), and hypopharynx volume (WMD: 39.85; 95% CI: -809.77, 889.46). MARPE appears to be linked with long-term increases in nasal and nasopharyngeal volume. However, high-quality clinical trials are required to further verify the effects of MARPE treatment on the upper airway.

An improvement of upper airway flow in patients treated with rapid maxillary expansion: a Cone Beam Computed Tomography study

Rapid Maxillary Expansion (RME) is an orthopaedic treatment used to correct the transverse deficit of the maxilla. Most often, this defect is diagnosed in mouth-breathing patients. Rapid Palatal Expander (RPE) treatment increases the upper airways’ volume and decreases resistance, promoting physiological nasal breathing. The aim of this study is to measure the volume of the upper airways by employing Cone-beam Computed Tomography (CBCT) to evaluate the anatomical space where the major effects of RME occurred. Twenty-four subjects (mean age, 10.17 ± 1.75 years) treated with McNamara-type rapid palatal expander were selected. Two CBCT scans were taken for each patient: the first at the beginning (T0) and the second at the end of the treatment (T1). For each CBCT scan, Total Volume (TV), Retropalatal Volume (RPV) and Retroglossal Volume (RGV) were measured with the software ITK-Snap. The statistical analysis was performed using the paired samples t-test, with a p-value of 0.05. RPV significantly increased (Δ T1-T0: 680.75 mm3 ± 792.63 mm3, P<0.05). No significant changes were found in TV (Δ T1-T0: 452.92 mm3 ± 3091.7 mm3, P>0.05) and in RGV (Δ T1-T0: 166.92 mm3 ± 666.97 mm3, P>0.05). In this study, patients showed a statistically significant increase in RPV after RPE treatment. The CBCT scans provide only quantitative volumetric data, so it would be appropriate to determine the clinical significance of the obtained results with a functional examination (for example, rhinomanometry). The radiological protocol should be standardised to overcome limitations such as tongue posture during scan recording, swallowing and breathing control. Further studies are needed to evaluate the long-term stability of these effects on the airways.

Evaluation of the Changes of the Intercanine and Intermolar Widths Following Palatal Expansion in the Mixed Dentition Patients with Bilateral Posterior Crossbite: A Systematic Review.

This systematic review aimed to identify the intercanine and intermolar width changes following palatal expansion in bilateral posterior crossbite (PXB) in mixed dentition. This review was registered in the PROSPERO database (CRD42021275833). All randomized controlled trials (RCT) and non-RCT articles between 1980 and August 2022 on the palatal expansion of bilateral PXB in mixed dentition were searched in seven online databases (Google Scholar, Ovid, Web of Science, Scopus, EBSCOHost, Cochrane Library and PubMed). The risk of bias (RoB) of the articles included was analyzed using the Joanna Briggs Institute (JBI) critical appraisal tool. Three non-RCT studies were included and showed a low risk of bias. Meta-analysis on the changes in intercanine and intermolar widths was not performed due to study design heterogeneity. One study reported an over-correction of the bilateral PXB. There is a need for more RCT studies with standardized landmark measurements, outcome assessment methods and retention periods to investigate the interdental changes following palatal expansion.

Short-term and long-term effects of miniscrew-assisted and conventional rapid palatal expansion on the cranial and circummaxillary sutures

The objective of this study was to analyze the short-term and long-term effects of miniscrew-assisted rapid palatal expansion (MARPE) and conventional rapid palatal expansion (RPE) appliances on cranial and circummaxillary sutures as compared with a matched control group. One hundred and eighty cone-beam computed tomography scans for 60 subjects were evaluated for the 3 groups: (1) MARPE (n= 20; aged 13.7 ± 1.74 years), (2) RPE (n= 21; age 13.9 ± 1.14 years), and (3) control (n= 19; age 13.3 ± 1.49 years) at pretreatment (T1), postexpansion (T2), and posttreatment (T3) (T1 to T3: MARPE, 2 years 8 months; RPE, 2 years 9 months; control, 2 years 7 months). Frontonasal suture, frontomaxillary suture, zygomaticomaxillary suture, zygomaticofrontal suture, intermaxillary suture, pterygomaxillary suture, nasomaxillary suture, and zygomaticotemporal suture were measured on the right and left sides for all 3 time labels. In addition, midpalatal suture was measured at the incisor, canine, and molar levels. Within-group analysis showed that MARPE and RPE led to a significant increase in the widths of frontonasal, frontomaxillary, intermaxillary, nasomaxillary, and midpalatal suture at incisor, canine, and molar levels at T2 compared with T1. Between-group analysis showed that MARPE and RPE significantly increased the width of the intermaxillary and midpalatal suture at the incisor, canine, and molar compared with controls at T2. In the long term, between-group comparisons showed no significant difference among the 3 groups except that MARPE led to a significant increase in the width of midpalatal suture at incisor, canine, and molar levels compared with RPE and controls at T3. MARPE led to a significant increase in the width of the midpalatal suture at incisor, canine, and molar levels compared with RPE and controls in the long term. There was no difference in the width of other cranial and circummaxillary sutures among the 3 groups in the long term.

Different rapid maxillary expansion methods in the treatment of adult patients with obstructive sleep apnea hypopnea syndrome

Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common sleep respiratory disorder characterized by upper respiratory collapse during sleep, with a high prevalence and potentially fatal complications. Currently, maxillary transverse deficiency are considered to be an important pathogenic factor of OSAHS. For patients with poor compliance with positive airway pressure therapy, rapid maxillary expansion can increase the volume and ventilation of the upper respiratory tract, which is an alternative treatment. This paper reviewed the current research on surgically assisted rapid palatal expansion, miniscrew assisted rapid palatal expansion, and distraction osteogenesis maxillary expansion in the treatment of adult OSAHS. By comparing the indications, contraindications, complications, efficacy and long-term stability of the three treatment methods, it provided reference for treatment of patients with OSAHS.

Republication de : Pediatric maxillary expansion has a positive impact on hearing? A systematic review and meta-analysis

Hearing loss is a highly prevalent condition in the pediatric population. Pediatric maxillary expansion is a widespread treatment to address transverse maxillary deficiency. First reports describing an association between improvements for patients with HL and PME initiated in the 1960s. In this systematic review and meta-analysis we aim to review the role of maxillary expansion in reducing conductive hearing loss in pediatric population. Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked. Main outcome was expressed as the difference between air-bone gap, compliance, ear volume and conductive hearing thresholds before and after treatment and the 95% confidence interval. A total of 10 studies (218 patients) met inclusion criteria. The pooled data in the meta-analysis under a random effects model shows a statistically significant difference of 10.57 dB mean reduction after palatal expansion. The air-bone gap was significantly reduced by 5.39 dB (CI 95% 3.68, 7.10). Compliance and volume were assessed in three studies, with a non-significant positive difference in the compliance (0.14) and a statistically significant difference for volume (0.80) after palatal expansion. This systematic review and meta-analysis found a positive effect of pediatric maxillary expansion in conductive hearing loss in well-select children. However, results cannot be extrapolated for children with conductive hearing loss without an accompanying orthodontic indication (maxillary constriction). It showed that the existing prospective studies exhibited qualitative pitfalls, limiting the ability to obtain conclusive evidence about the role of pediatric maxillary expansion on conductive hearing loss in children.

Comparison of palatal volume and surface changes between bone-borne and tooth-tissue-borne maxillary expansion on cone beam computed tomography digital cast models.

To compare the changes of palatal volume and area in patients treated with tooth-tissue-borne palatal expanders (conventional Haas) and miniscrew-supported palatal expanders (modified Haas). The sample included casts of 22 patients treated as part of a clinical study at the Department of Orthodontics, Al-Azhar University, to correct their crossbite malocclusion. Patients were divided equally into two groups upon arrival. The first group, with a mean age of 12 years and 6 months, received the miniscrew-supported palatal expander. The second group, with a mean age of 12 years and 2 months, received the Haas design-palatal expansion appliance. Pre- and post-expansion dental casts were cone beam computed tomography scanned and the slices were constructed into 3D volumes. Fully automated superimposition was done for pre- and post-expansion 3D models. Palatal volume and area were determined, and all measurements were carried out blindly. Paired t-test was used to assess the mean differences within each group and Welch's t-test was applied to assess the mean changes between the two groups. Shapiro-Wilk test was used to test for the normality of the data. There were no statistical differences in volume changes either within each group or between the groups. Although area changes were statistically significant within each group, the difference between the groups was not significant. Changes that result from the use of either method to expand the upper arch occur primarily in the shape of the palate, but not in its size.

Effects of Rapid Palatal Expansion on the Upper Airway Space in Children with Obstructive Sleep Apnea (OSA): A Case-Control Study

Obstructive Sleep Apnea (OSA) in children needs a multidisciplinary approach. Even if the first-line treatment of pediatric OSA is adenotonsillectomy, nowadays rapid palatal expansion (RPE) is considered a valid additional treatment. The aim of this study is to evaluate cephalometric changes in upper airways dimensions after rapid palatal expansion (RPE) in children suffering from Obstructive Sleep Apnea (OSA). A total of 37 children (range age 4-10 years) with diagnosis of OSA referred to Dentistry Unit of Bambino Gesù Children's Research Hospital IRCCS (Rome, Italy) were included in this pre-post study and underwent lateral radiographs at the start (T0) and at the end (T1) of a RPE treatment. Inclusion criteria were: diagnosis of OSA confirmed by cardiorespiratory polygraphy (AHI > 1) or pulse oximetry (McGill = >2), skeletal maxillary contraction evaluated by presence of posterior crossbite. A control group of 39 untreated patients (range age 4-11 years), in good general health, was set up. A paired T-test was used to investigate the statistical differences between T0 and T1 values in both groups. The results showed a statistically significant increase of nasopharyngeal width in the treated group after RPE treatment. Moreover, the angle that identifies mandibular divergence compared to palatal plane (PP-MP°) was significantly reduced. In the control group, no statistically significant differences were observed. The present study showed that RPE treatment determines a significant sagittal space increase in the upper airways space and a counterclockwise mandibular growth in children with OSA compared to a control group. These results suggest that a widening of the nasal cavities induced by RPE may support a return to physiological nasal breathing and promote a counterclockwise mandibular growth in children. This evidence confirms the crucial role of the orthodontist in the management of OSA in pediatric patients.

Three-Dimensional Analyses of Postoperative Effects of Surgically Assisted Rapid Palatal Expansion (SARPE) on the Soft Tissue of the Midface Region and the Upper Airway Space Using Stereophotogrammetry and Cone Beam Computed Tomography (CBCT).

Surgically assisted rapid palatal expansion (SARPE) is an established method to treat transverse maxillary hypoplasia in skeletally mature adult patients. SARPE affects the surrounding soft tissue. In addition, effects on the airway and breathing have been described. Aim of this study was to assess the effects of SARPE on the nasal soft tissue and the upper airway by means of three-dimensional stereophotogrammetry and cone beam computed tomography (CBCT). This retrospective study used preoperative and postoperative cone beam computed tomography (CBCT) scans and three-dimensional stereophotogrammetry. Ten skeletally adult patients (4 male, 6 female; mean age 27.68 years) with transverse maxillary hypoplasia were included. Patients had undergone SARPE procedure, performed by the same surgical team using the same technique. Nasal soft tissue changes were analyzed, using three-dimensional stereophotogrammetry records taken preoperatively (t0) and at the postoperative checkup appointment (t1). The upper airway was assessed using CBCT scans for surgical planning (t0) and the first scan taken after SARPE (t1). In stereophotogrammetry, it was shown that only a few soft tissue nasal parameters increased significantly and SARPE leads to mainly clinically irrelevant changes in nasal soft tissue. In CBCT, only a significant increase in nasopharyngeal airway volume was found. Results were in alignment with literature. The effects of SARPE on the nasal soft tissue are mostly statistically insignificant and clinically irrelevant. Airway volume significantly increased in the nasopharyngeal area. Further research on SARPE effects should be conducted to reinforce SARPE as a treatment option for sleep apnea patients.

Comparative Evaluation of Skeletal and Dental Effects of Mini-Implant Assisted and Corticopuncture-Facilitated Rapid Palatal Expansion in Adults: A Randomized Clinical Study

Abstract Introduction: Conventional rapid maxillary expansion (RME) in adults is difficult due to increased skeletal maturity of the midpalatal suture. Surgically assisted rapid palatal expansion (SARPE) treatment is recommended for adults with strongly consolidated sutures but has lesser acceptance due to its invasive nature. Mini-implant-assisted rapid palatal expansion (MARPE) produced dentoalveolar side effects along with some skeletal effects in adults while being highly successful in adolescents and young adults. A lesser invasive technique combined with a purely bone-borne-rapid-maxillary-expansion appliance (BBRME) is suggested in this study to achieve maximum skeletal effects and minimize the dentoalveolar side effects of expansion in adults with completely fused midpalatal sutures as an alternative to SARPE. Aim: This study aims to evaluate and compare skeletal and dental effects of mini-implant assisted, and corticopuncture-facilitated rapid palatal expansion in adults. Material and Methods: A randomized clinical study was performed on 18 patients (mean age 20.77 years) who were randomly divided into two groups: Group A (Corticopuncture-facilitated BBRME) and Group B (conventional MARPE). Pretreatment (T0) and postexpansion (T1) skeletal and dental effects of both the groups were analyzed using cone-beam computed tomography imaging. Results: A student’s paired t-test was used to evaluate the difference in expansion achieved between the two groups (T1-T0). Group A (BBRME with corticopunctures) showed increased transverse widths at the basal bone, nasal base, and jugal processes. Group B (conventional MARPE) showed increased inclination of the posterior teeth indicating dental tipping. Both groups were successfully treated with their respective protocols but dentoalveolar side effects were significantly less in group A (BBRME) suggesting a better prognosis in BBRME group. Conclusions: Greater skeletal changes were seen in group A (BBRME) (P < 0.05*) than in group B. Group B (MARPE) showed more dental side effects like dental tipping and lesser skeletal expansion. Corticopuncture-facilitated bone-borne RME (BBRME) is a viable and efficient method of maximizing skeletal expansion in adults with fully obliterated midpalatal sutures.

Suppressing STAT3 activation impairs bone formation during maxillary expansion and relapse

The mid-palatal expansion technique is commonly used to correct maxillary constriction in dental clinics. However, there is a tendency for it to relapse, and the key molecules responsible for modulating bone formation remain elusive. Thus, this study aimed to investigate whether signal transducer and activator of transcription 3 (STAT3) activation contributes to osteoblast-mediated bone formation during palatal expansion and relapse.In total, 30 male Wistar rats were randomly allocated into Ctrl (control), E (expansion only), and E+Stattic (expansion plus STAT3-inhibitor, Stattic) groups. Micro-computed tomography, micromorphology staining, and immunohistochemistry of the mid-palatal suture were performed on days 7 and 14. In vitro cyclic tensile stress (10% magnitude, 0.5 Hz frequency, and 24 h duration) was applied to rat primary osteoblasts and Stattic was administered for STAT3 inhibition. The role of STAT3 in mechanical loading-induced osteoblasts was confirmed by alkaline phosphatase (ALP), alizarin red staining, and western blots.The E group showed greater arch width than the E+Stattic group after expansion. The differences between the two groups remained significant after relapse. We found active bone formation in the E group with increased expression of ALP, COL-I, and Runx2, although the expression of osteogenesis-related factors was downregulated in the E+stattic group. After STAT3 inhibition, expansive force-induced bone resorption was attenuated, as TRAP staining demonstrated. Furthermore, the administration of Stattic in vitro partially suppressed tensile stress-enhanced osteogenic markers in osteoblasts.STAT3 inactivation reduced osteoblast-mediated bone formation during palatal expansion and post-expansion relapse, thus it may be a potential therapeutic target to treat force-induced bone formation.

Correlation of age and skeletal effects after miniscrew assisted rapid palatal expansion.

To evaluate the skeletal and dentoalveolar effects after miniscrew assisted rapid palatal expansion (MARPE) and their correlation with the age of the patients. Settings and sample population: Sample comprised 19 patients with maxillary atresia and posterior crossbite, treated with MARPE. Cone-beam computed tomographs (CBCT) were evaluated before and after expansion. Three patients were excluded since the midpalatal suture was not opened. Thus, 16 patients (11 female; 5 male) were evaluated, with a mean age of 24.92 years (s.d.=7.60). The time between the installation of MARPE and the second CBCT was, on average, 1.64 months (s.d.=1.12). Linear and angular measurements were performed: bone thickness and level, tooth inclination, transverse dental widths, and nasal base and jugula widths. Comparison was performed with dependent t-test and correlations with Pearson coefficient. MARPE was 84.2% successful. There was significant reduction in the buccal bone thickness of the first molars and an increase in the palatal bone thickness of all teeth. First molars showed significant buccal inclination. All transverse dimensions showed a significant increase. Older patients tended to show a less maxillary transverse skeletal increase. A greater maxillary transverse increase was accompanied by a greater intermolar width increase and also a greater buccal bone loss in the mesiobuccal roots of the maxillary first molars. MARPE corrected the maxillary atresia in adult patients, with significant transverse increases, a slight decrease in buccal bone thickness and buccal inclination of the first molars, combining skeletal and dental effects. Older patients presented less transverse skeletal increases. Key words:Palatal expansion technique, skeletal anchorage, cone-beam computed tomography.

A comparison of the quadhelix and the nickel-titanium palatal expander in the treatment of narrow maxillary arches: A prospective clinical study

The study aimed to compare the effects of quadhelix and nickel-titanium (NiTi) expander appliances on lower facial height, to quantify, and evaluate dentoalveolar and orthopedic changes in transverse plane, respectively, to estimate the difference in changes between these two appliances.Twenty patients, ten for the quadhelix and NiTi expander in the two-appliance group, respectively, participated in this study. A total of 8 readings, 1 for clinical facial height, 2 for model analysis, and 5 for posteroanterior cephalometric analysis were recorded. The statistical tests used were, Student's unpaired and paired t-tests.Both appliances individually, produced statistically highly significant (p < 0.01) expansion every month in both premolar and molar areas with more uniform expansion for quadhelix and less expansion in NiTi palatal expander in the premolar region initially. The skeletal to dental change ratio showed that there was more dental change than skeletal with no inter-appliance differences statistically while assessing the PA cephalometric readings.This study infers that both appliances are equally efficacious maxillary expanders, which are primarily dentoalveolar and not skeletal (p < 0.05).

Effect of Injectable platelet-rich fibrin (i-PRF) on new bone formation in surgical expansion with mini-screw assisted rapid palatal expander: A dog model study

The objective of the study is to test whether the local injection of i-PRF may affect osteoblast, blood vessels and new bone formation in surgically expanded mid palatal suture using maxillary skeletal expander.Eighteen adult male local breed dogs were divided randomly into three groups: group I (control), includes the expansion with maxillary skeletal expander that was done without corticotomy and i-PRF. Group II, involves the expansion that was done with mid palatal corticotomy but without i-PRF injection. Group III, has the expansion that was done with mid palatal corticotomy and has injection with 2 ml of i-PRF. Each group consisted of 6 dogs which were subdivided into 3 dogs. Three dogs were sacrificed after 15 days and the other 3 dogs were sacrificed after 45 days. The number of osteoblast, blood vessels and new bone formation percentage were statistically analyzed using Sigma plot platform. Mean and standard error, ANOVA and Duncan were performed among the different groups. Values of P ≤ 0.05 were considered significant.After expansion, the i-PRF group demonstrated a considerable increase in the amount of new bone in the mid-palatal suture at 15 and 45 days compared with other 2 groups which were indicated by highest percentages of new bone formation (29.30% of 15 days and 76.55% at 45 days) if compared to control group which were (7.72% at 15 days and 22.30% at 45 days). The corticotomy groups were in between, 15.33% and 46.84% respectively. Moreover the number of osteoblasts was higher in corticotomy with i-PRF group on 15 days and decreased on 45 days than the other two groups, while the blood vessels were highest in this group than the other two groups both on 15 and 45 days.I-PRF enhanced the production of osteoblast, blood vessels, and new bone in the surgically expanded mid palatal suture.

A method based on 3D affine alignment for the quantification of palatal expansion.

The current methodologies to quantify the palatal expansion are based on a preliminary rigid superimposition of 3D digital models representing the status of a given patient at different times. A new method based on affine alignment is proposed and compared to the gold standard, leading to the automatic analysis of 3-dimensional structural changes and to a simple numeric quantification of overall expansion vector and a better alignment of the digital models. 40 digital models (timing span delta 25.8 ± 12.5 months) from young patients (mean age 10.7 ± 2.6) treated with two different palatal expansion techniques (20 subjects with RME-Rapid Maxillary Expander, and 20 subjects with NiTiSE, NiTi self-expander) were superimposed with the new affine alignment technique implemented as an extension package of the open-source MeshLab, from a golden standard starting point of rigid alignment. The results were then compared. The new measurement function indicates a mean expansion expressed in a single numeric value of 9.3%, 10.3% for the RME group and 8.4% for the NiTiSE group respectively. The comparison with the golden standard showed a decrease to the average error from 0.91 mm to 0.58 mm. Affine alignment improves the current perspective of structural change quantification in the specific group of growing patients treated with palatal expanders giving the clinician useful information on the 3-dimensional morphological changes.

Camouflage Treatment of Skeletal Class III Malocclusion by Maxillary Total Arch Extrusion

In patients with skeletal Class III malocclusion and insufficient maxillary incisal display, maxillary total arch extrusion can be considered as one of the camouflage treatments to improve the smile and profile esthetics as well as the mandibular prognathism. This case report describes the use of MARPE (micro-implant assisted rapid palatal expansion) and maxillary total arch extrusion to treat a patient with skeletal Class III malocclusion who had transverse discrepancy and insufficient maxillary incisal display. The goal of the procedure was to improve the patient’s occlusion as well as facial esthetic. The maxillary removable anterior bite plate, mandibular posterior mini-implants, and vertical elastics were applied to attain the therapeutic goal. The improvement of the occlusal relationship and an esthetic smile were achieved through maxillary total arch extrusion and clockwise rotation of the mandible.

Comparison of 3 different bone-borne type expansion appliances used in surgically-assisted rapid palatal expansion: A finite element analysis

This study aimed to compare the effects of 3 different bone-borne type expansion appliances used in the surgically-assisted rapid palatal expansion (SARPE) by finite element analysis. Three different miniscrew-supported palatal expansion appliances were modeled. Median and lateral osteotomies were performed without pterygomaxillary suture separation. Model I consisted of a palatal expander with 2 miniscrews placed 4 mm far from the midpalatal suture. In model II, 2 miniscrews were located at the alveolar ridge between the first molar and the second premolar. In model III, 4 miniscrews were placed as a combination of the first and second models. Stress distributions and amount of displacements were evaluated with Ansys software (version 19.2; Ansys, Canonsburg, Pa) for 5-mm expansion in a symmetrical finite element analysis model to reflect the clinical situation. SARPE simulation using miniscrew-assisted maxillary expanders for all models showed a rotation and tipping of the maxilla. The largest displacement was found for the anterior part of the palate in model II and the posterior part in model III. Although a wedge-shaped expansion pattern was observed in all models, this form was more prominent in model II. The highest stress value (0.91 MPa) was measured in model I, and the lowest value (0.004 MPa) was measured in model II for the anterior nasal spine region. The highest stress value (0.51 MPa) was measured in model III, and the lowest value (0.12 MPa) was measured in model II for the posterior nasal spine region. The lowest stress values were measured in model II for all the craniofacial and maxillofacial structures. Among the models, the lowest stress distribution conditions for craniofacial and maxillofacial structures were found in model II. The largest displacement was found at the incisors and anterior part of the maxilla for model II. The greatest displacement was found at the posterior region for model III.

Evaluation of miniscrew-assisted rapid palatal expansion success by comparing width of circummaxillary sutures before expansion in adult male patients.

To investigate the relationship between circummaxillary sutures and miniscrew-assisted rapid palatal expansion (MARPE) success in adult male patients and to evaluate the correlation between the width of the sutures and the maxilla expansion ratio. This retrospective study comprised 40 adult male patients treated with MARPE divided into a separation group (N = 20, mean age, 21.9 years) consisting of subjects with midpalatal suture opening and a nonseparation group (N = 20, mean age, 21.7 years) consisting of subjects with no midpalatal suture opening. Cone-beam computed tomography images were obtained before MARPE expansion for both groups and after expansion for the separation group. Vertical and horizontal skeletal relationships, palate length, and widths of 10 circummaxillary sutures before expansion were compared. The correlation between maxilla expansion ratio (jackscrew expansion to maxillary expansion ratio) and circummaxillary suture widths was also analyzed in the separation group. There were no significant differences in age, vertical and horizontal skeletal relationships, and palate length between the two groups. Zygomaticomaxillary, pterygomaxillary, midpalatal, and transverse palatine sutures showed significantly greater width in the separation group (P < .05). The zygomaticomaxillary suture showed the greatest difference (Δ = 0.36 mm) between the groups. The zygomaticomaxillary and pterygomaxillary sutures showed significant positive correlation with the maxilla expansion ratio (P < .01). In adult male patients, greater circummaxillary suture widths before MARPE expansion, especially zygomaticomaxillary and pterygomaxillary sutures, resulted in a better chance of successful suture separation and more maxillary expansion.

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

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