Palatal Expansion Research Articles

Dento-Skeletal Class III Treatment with Mixed Anchored Palatal Expander: A Systematic Review

Bone-anchored appliances for the treatment of Class III malocclusions have recently been found to reduce the dentoalveolar effects caused by conventional tooth-borne devices while also improving orthopaedic outcomes in growing patients. The goal of this systematic review was to compare the outcomes of skeletal Class III interceptive treatment with dental anchoring devices to those achieved with mixed anchored palatal expanders. The inclusion criteria were as follows: patients who were treated with hybrid anchored palatal expanders and different maxillary advancement appliances. Study quality was estimated using the Newcastle–Ottawa scale. A search on the Pubmed, Scopus, Embase and Cochrane Library databases yielded 350 papers. Following the initial abstract selection, 65 potentially acceptable papers were thoroughly examined, resulting in a final selection of 9 articles. The results in the short-term showed that combined tooth-borne and bone-borne appliances for rapid maxillary expansion might be recommended in protocols of skeletal Class III treatment to obtain more skeletal effects and reduce side effects on the upper teeth.

Dental Arch Changes with Two Different Trans-Palatal Arch

Background: Rapid maxillary expansion (RME) is a dentofacial orthopedic treatment often used to treat patients with narrow palate and transverse maxillary growth deficiency. Introduction: This treatment leads to correction of posterior dental crossbites, coordination of the upper and lower arches and gaining arch perimeter in patients with tooth size/arch size discrepancies. To stabilize the results obtained with RME and to limit or avoid the relapse, the use of Transpalatal Arch (TPA) would be recommended. Objectives: The aim of this study is to evaluate short-term maxillary changes in patients treated with RME followed by TPA with and without palatal arms. Materials and Methods: 30 patients, 16 females and 14 males (mean age of 9.7 yrs ranging between 9 and 12), were treated by expansion with palatal Hyrax-type expander. After this period, it was removed and one of the two different types of TPA was used. The two different TPA were a 0.036-inch stainless steel wire with a loop directed mesially in the middle, one maintained the original design (TPA), the second one presented arms extended to canines (TPAa). Dental casts were collected for each patient for each treatment step; before (T0), after expansion (T1) and after TPA or TPAa (T2). To assess differences in dental arches after the two treatment phases, three-dimensional (3D) dental casts were used to make more predictable measurements compared with caliper measurements that presented intra-examiner and inter-examiner measurements errors. Results: In TPAa group, differences between the value at the end of the retention period and at the end of expansion showed no statistical significance. Instead in TPA group, the same measurements suggested a reduction of value in almost all dental transverse diameters. Statistically significant differences in dental measurements were found between TPAa and TPA. Conclusion: Results confirm the hypothesis that TPAa can allow to better maintain dental transverse dimensions.

Changes in the nasal and pharyngeal airway volume with miniscrew-assisted rapid palatal expansion appliances

Objectives: The purpose of this study was to assess the volumetric changes in the nasal and pharyngeal airway volume in patients with maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion (MARPE) appliances. Material and Methods: The pre- and post-treatment cone-beam computed tomography scans of 20 subjects who underwent treatment with the MARPE appliance as part of their orthodontic treatment were included in the study. Pre- and post-expansion airway volume measurements of the nasal cavity, nasopharynx, and oropharynx were measured. Linear measurements of the skeletal structures surrounding the nasal cavity were taken to assess the pattern of airway expansion. Paired t-tests were used to evaluate nasal and pharyngeal airway volume changes with expansion. Pearson correlation test was utilized to assess the relationship between nasal and pharyngeal volume changes. Results: A total of 17 out of 20 samples had a successful split of the mid-palatal sutures. A significant increase in nasal airway volume (12.0%) was found post-expansion. In addition, a significant increase in linear measurements of the nasal cavity base width in the frontal plane (7.1%) and both the anterior and posterior widths in the transverse dimension (9.4% and 3.4%, respectively) were found. Significant positive correlations were found between airway volumes and increase in width of the maxillary expansion appliance. Conclusion: The effects of maxillary expansion with a MARPE appliance include an increase in nasal cavity volume, but not the nasopharyngeal and the oropharyngeal airway volume. The nasal cavity expands in a triangular pattern in both the frontal and transverse dimensions following orthopedic expansion with the MARPE appliance. Increase in airway volume is a result of the increase in width of the maxillary expansion appliance.

Marpe - An Effective Treatment Modality for Transverse Discrepancy Correction in Young Adults: A Case Report

Growth in maxilla occurs either by apposition of bone at the suture or by surface remodeling . Many studies have reported that by the late teens, interdigitation and areas of bony bridging across the suture develop to the point that maxillary expansion becomes impossible. Conventional expanders were effective in children and young adolescents but when used during late adolescent and adulthood it caused more of dental tipping and less to no skeletal expansion. The inclusion of mini screws in conventional rapid palatal expanders converts it into a MARPE appliance. The Mini screw warrants greater skeletal expansion, keeping the dental expansion and associated unwanted effects to a minimum. The objective of this case report is to show the correction of bilateral posterior crossbite in an adult patient using Miniscrew Assisted Rapid Palatal expansion followed by fixed orthodontic appliance therapy. Keywords: MARPE; Rapid palatal expansion; Maxillary skeletal expansion

“Appliance First” or “Bone First” for miniscrew assisted rapid palatal expansion?

“Appliance First” or “Bone First” for miniscrew assisted rapid palatal expansion?

Effectiveness of miniscrew assisted rapid palatal expansion using cone beam computed tomography: A systematic review and meta-analysis.

ObjectiveThis study aims to examine the effectiveness of miniscrew assisted rapid palatal expansion (MARPE) treatment in late adolescents and adult patients using cone-beam computed tomography (CBCT).MethodsLiterature search was conducted in five electronic databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) based on the PICOS keyword design focusing on MARPE. Out of the 18 CBCT screened outcomes, only nine parameters were sufficient for the quantitative meta-analysis. The parameters were classified into three main groups 1) skeletal changes, 2) alveolar change, and 3) dental changes. Heterogeneity test, estimation of pooled means, publication bias, sensitivity analysis and risk of bias assessment were also performed.ResultsUpon database searching, only 14 full-text articles were qualified from the 364 obtained results. Heterogeneity test indicated the use of the random-effects model. The pooled mean estimate were as follows 1) Skeletal expansion zygomatic width, 2.39 mm; nasal width, 2.68 mm; jugular width, 3.12 mm; and midpalatal suture at the posterior nasal spine and anterior nasal spine, 3.34 mm and 4.56 mm, respectively; 2) Alveolar molar width expansion, 4.80 mm; and 3) Dental expansion inter-canine width, 3.96 mm; inter-premolar width, 4.99 mm and inter-molar width, 5.99 mm. The percentage of expansion demonstrated a skeletal expansion (PNS) of 55.76%, alveolar molar width expansion of 24.37% and dental expansion of 19.87%.ConclusionsIn the coronal view, the skeletal and dental expansion created by MARPE was of the pyramidal pattern. MARPE could successfully expand the constricted maxilla in late adolescents and adult patients.

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

BackgroundThis 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.MethodsThis 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.ResultsThe 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).ConclusionsMidpalatal 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).

Long-term stability of Class III malocclusion treatment with maxillary transversal deficiency, short roots, gingival recession, and alveolar bone loss

• The SARPE in a patient with short root, gingival recession, and alveolar bone loss. • SAPE in the absence of atresic morphology of the palate for a skeletal transverse discrepancy. • Long-term periodontal stability is achieved in the case of reduced periodontal support tissues. • Special care in orthodontic treatment of shortened roots and alveolar bone loss. Orthodontic treatment in patients with Class III malocclusion can be complex, particularly when associated with other problems. This case report describes the retreatment of a 32-year-old woman with Class III malocclusion, transverse maxillary deficiency, short roots, and gingival recession. The patient was retreated with fixed appliances combined with surgically assisted rapid palatal expansion. The results of the debonding were excellent esthetics, good intercuspation, gingival health with adequate overjet, and overbite. After 22 months of treatment, the proposed goals (dental Class III relationship correction and transverse maxillary deficiency) were obtained. After the 5-year follow-up, the sagittal and transverse relationship remained stable.

Skeletal and dental changes after microimplant-assisted rapid palatal expansion (MARPE) – a Cephalometric and Cone-Beam Computed Tomography (CBCT) study

ABSTRACT Purpose The maxillary transverse discrepancy is common in orthodontic practice. Rapid palatal expansion has traditionally been used before puberty, but the skeletal effect is limited. Recently, micro-implant-assisted rapid palatal expansion (MARPE) has been proven to be effective in adolescents and adults. The purpose of this study is to assess the skeletal and dental 3-dimensional outcomes after MARPE. Materials and methods Nineteen subjects who presented with a maxillary transverse discrepancy and received MARPE treatment were included in this study. Cephalometric radiographs and Cone-Beam Computed Tomography (CBCT) images were obtained and analysed at the initial (T1) and the end of the expansion (T2). The Wilcoxon signed-rank test was used to evaluate the differences between the two time points. Results The results demonstrated anteroposterior correction. The SNA, ANB, FH-NA, N-A-Pog, A-Na perpendicular (mm) and U1-Nasion perpendicular (mm) all increased from T1 to T2, which explained the maxillary advancement after MARPE. The SN-MP, PP-MP and SNB changes indicated a mandible backward rotation followed expansion. In the CBCT analysis, the average expansion amount was 5.5 mm, of which 71.1% was due to a skeletal effect. In addition, the expansion pattern was almost parallel with a ratio of 83.2% from PNS to ANS. Conclusions MARPE treatment can provide successful transverse correction with near parallel expansion of the maxilla in the coronal and axial planes. Maxillary advancement and a mandibular backward rotation associated with MARPE can provide positive correction in the sagittal plane. As dentoalveolar tipping was limited, the expansion result was mainly skeletal.

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

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

Evaluation of the Effects of Mandibular Lingual Arch on Dentoalveolar Structures in Orthopedic Face Mask with Rapid Palatal Expansion Treatment of Class III Malocclusions

Evaluation of the Effects of Mandibular Lingual Arch on Dentoalveolar Structures in Orthopedic Face Mask with Rapid Palatal Expansion Treatment of Class III Malocclusions

The Impact of Fan-Type Rapid Palatal Expanders on Speech in Patients With Unilateral Cleft Lip and Palate.

Rapid palatal expanders (RPEs) are commonly used in patients with cleft lip and palate (CLP) prior to secondary alveolar bone grafting (SABG). Their position and size can impede tongue movement and affect speech. This study assessed changes in perception and production of speech over the course of RPE treatment. Prospective longitudinal. Tertiary university-affiliated hospital. Twenty-five patients with unilateral CLP treated with Fan-type RPEs, and their parents. Patient and parent speech questionnaires and patient speech recordings were collected at baseline before RPE insertion (T1), directly after RPE insertion (T2), during RPE expansion (T3), during RPE retention (T4), directly after RPE removal but before SABG (T5), and at short-term follow-up after RPE removal and SABG (T6). Ratings for patient and parent questionnaires, first (F1) and second (F2) formants for vowels /a/, /i/, and /u/, and nasalance scores for non-nasal and nasal sentences, were obtained and analyzed using mixed model analyses of variance. Ratings worsened at T2. For the vowel /a/, F1 and F2 were unchanged at T2. For the vowel /i/, F1 increased and F2 decreased at T2. For the vowel /u/, F1 was unchanged and F2 decreased at T2. Nasalance was unchanged at T2. All outcome measures returned to T1 levels by T4. RPE insertion resulted in initial adverse effects on speech perception and production, which decreased to baseline prior to removal. Information regarding transient speech dysfunction and distress may help prepare patients for treatment.

Long-term effects on alveolar bone with bone-anchored and tooth-anchored rapid palatal expansion

The purpose of this study was to evaluate the long-term effects of bone-anchored and tooth-anchored expansion appliances on alveolar bone in vertical and horizontal dimensions, compared with controls, using cone-beam computed tomography. We evaluated 180 cone-beam computed tomography scans for 60 patients at 3-time points: T1 (pretreatment), T2 (postexpansion), and T3 (posttreatment), for 3 groups: bone-anchored expansion appliance (BA), tooth-anchored expansion appliance (TA), and controls (T1-T3: BA, 2 years 8 months; TA, 2 years 9 months; control: 2 years 7 months). The intermolar width, molar angulation, palatal width, vertical buccal bone height, buccal bone thickness at the alveolar crest, and root apex were measured in the 3 groups at different time points. In the short term, both BA and TA led to a statistically significant increase in the intermolar width and vertical buccal bone loss after expansion compared with controls. Vertical buccal bone loss was significantly greater in TA than in BA. In addition, TA led to significantly increased molar angulation (buccal tipping) compared with controls at T2. There were no significant differences in the 3 groups in the long term except vertical buccal bone loss, which was significantly greater in TA than controls. A substantial correlation was found between molar angulation and vertical buccal bone loss, and a moderate negative correlation was found between intermolar width and buccal bone thickness at the alveolar crest at T3. There was no difference in the treatment outcomes between the 3 groups in the long term except vertical buccal bone loss, which was significantly increased in the TA group compared with controls.

Does Maxillary Expansion Lead to Root Resorption?-A Comprehensive Review

The objective of this review article is to assess root resorption of conventional rapid maxillary expansion (RME) and mini screw assisted rapid palatal expansion (MARPE) with 2D and 3D radiographic imaging method. For this review article, the current literature was searched on the studies conducted on the effects of such expansion appliances on root resorption. Orthodontic patients with transverse maxillary defieiceny undergo maxillary expansion therapy for the correction of posterior crossbite. The evalution of root resorption in such patients can be done with either 2D radiographs such as perioapical radiograph, panoramic radiograph or 3D radiographs such as cone beam computed tomography. This review article will discuss the studies showing that conventional RME appliances can result in root resorption of molar teeth after the expansion procedure. In contrast, MARPE appliances have not shown significant root resorption after expansion procedures.

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

The objective of this study was to evaluate the effects of nonsurgical rapid maxillary expansion (RME) and surgically assisted RME (SARME) on palatal morphology and upper arch dimensions using three-dimensional (3D) models in skeletally mature patients. Thirty-eight skeletally mature patients with a maxillary transverse deficiency were divided into RME and SARME groups. Nineteen patients in the RME group (mean age, 19.16 ± 2.25 years) were treated using a full-coverage bonded acrylic splint expander; 19 patients in the SARME group (mean age, 20.38 ± 3.36) were treated using the banded palatal expansion appliance with hyrax screws. The 3D models were obtained before and after expansion. The maxillary dental arch widths, maxillary first molar angulation, palatal area, and palatal volume were calculated on the 3D models. All variables showed statistically significant changes after the retention period (P < .001). The maxillary arch width between first premolars (P < .05), the palatal area (P < .01), and the palatal volume (P < .05) significantly increased in the SARME group compared to the RME group. The maxillary first molar tipping in the RME group was significantly higher than that in the SARME group (P < .01). Although SARME has more positive effects in skeletally mature patients, nonsurgical RME can be considered as an alternative by evaluating surgical risks, periodontal status, and the need for skeletal expansion.

Miniscrew-assisted rapid palatal expansion appliance associated with a new cortical perforations protocol: A case series

• Successful maxillary expansion in older and skeletally mature patients was obtained. • Cortical perforations were performed with a trephine bur and reached the nasal floor. • Perforations in the midpalatal suture can improve miniscrew-assisted rapid palatal expansion. • Perforations in nongrowing patients can be a solution to ensure the midpalatal suture split. This case series describes the use of a miniscrew-assisted rapid palatal expansion (MARPE) appliance to orthopedically correct transverse maxillary deficiencies in four skeletally mature patients. In addition, cortical perforations were performed to ensure the midpalatal suture (MPS) split. Expansion forces were applied in the appliance to create negligible dental effects and true skeletal expansion, although patients presented interdigitated MPS. All patients presented posterior crossbites, and their ages ranged from 29 to 46 years. Eight cortical perforations were performed in all patients with a 2.0 mm trephine bur, inserted until the nasal cortical floor was perforated. The MARPE expanders were installed with four self-drilling miniscrews. The MPS was successfully opened in all patients, and all crossbites were resolved. The mean MPS opening in the area of the incisors was 3.27 mm, and at the first and second molars was 2.05 and 1.55 mm, respectively. The basal bone was increased by 3.8 mm, whereas the nasal cavity was increased by 2.75 mm. Negligible teeth tipping was observed. This case series demonstrates that MARPE associated with cortical perforations that reach the nasal floor can successfully split the MPS in skeletally mature patients.

Maxillomandibular Advancement for OSA: A 25-year perspective

The focus of this report is to analyze the pattern of maxillary expansion and complications in patients following surgical and non-surgical maxillary expansion presented for evaluation and second opinion. During a 30-months period, 28 patients presented for second opinion following maxillary expansion performed elsewhere. The indication for treatment was obstructive sleep apnea (OSA). All patients reported a lack of symptomatic improvements and problems associated with the treatment. Clinical examination with pre- and post-expansion cone beam computed tomography (CBCT), and treatment photographs were analyzed. Complete clinical records and CBCT were available in 22 patients for analysis. Six patients had undergone surgical expansion with distraction osteogenesis maxillary expansion (DOME), and 16 patients had undergone a variety of non-surgical expansion with different appliances. All the DOME patients had anterior nasal spine (ANS) separation without posterior nasal spine (PNS) separation. Diastema ranging between 10-16 mm was noted in the DOME patients, and the ratio of anterior diastema to ANS separation was between 2:1 to 3:1. Bone defects existed between the central incisors at 18 months or beyond following DOME in all the patients despite bone grafting attempts in four patients. Anterior gingival recession occurred in two patients and four incisor teeth required endodontic therapy with long-term guarded prognosis. Sixteen patients underwent non-surgical maxillary expansion with four different appliances, including anterior growth guidance appliance (AGGA), daytime-nighttime appliance (DNA), advanced lightwire functionals appliance (ALF), and mini-screw assisted rapid palatal expansion (MARPE). The midpalatal suture did not separate in any of the 16 patients, and the expansion pattern was purely dental and dentoalveolar in nature. Lateral dental tipping, thinning of the labial/buccal alveolar bone with gingival recession were noted in 10 patients. Significant mobility of the maxillary anterior teeth due to vertical and horizontal bone loss was noted in the five patients that underwent AGGA treatment. Different maxillary expansion methods are currently being performed with varying outcomes. Critical analyses of these methods are needed to determine their impact and whether the desired outcomes are achieved.

Effectiveness Of Rapid Palatal Expansion (RPE) In Class II Maloclusion and The Relationship With Muscle Contraction In Childhood Growth: Systematic Review

Background: In general, patients with Class II malocclusion are often associated with a narrow transverse dimension. The shape of the narrowed jaw space can cause various problems such as crowding, jaw mismatch, protrusion of incisors. Given this, the use of Rapid Maxillary Expansion or Rapid Palatal Expansion is a treatment option that has been the choice for decades.&#x0D; Objective: To systematically review the benefits of using RPE in the improvement of malocclusion in child development. This device is used to correct maxillary constriction and posterior crossbite. Methods: From four database sources PubMed, GoogleScholar, Wiley and Cochrane from 2016 to 2021. Thedatabase search process used the keywords "Rapid Palatal Expansion" "Rapid Maxillary Expansion" "Class II", from full journals published in less than 5years.&#x0D; Results: After eliminating duplicated articles, the abstract title of each article was analyzed from 136 articles which were excluded a total of 123 articles. Thetext of the article is complete and meets the eligibility as many as 13 articles.&#x0D; Conclusion: Rapid Palatal Expansion is effective in correcting class II malocclusion in child development.

Miniscrew-Assisted Rapid Palatal Expansion (MARPE): An Umbrella Review.

In postpubertal patients, maxillary transverse discrepancy is a common condition often requiring surgical approaches. To overcome the excess morbidity and discomfort, maxillary expansion through miniscrew-assisted rapid palatal expansion (MARPE) was proposed and studied in the last few years. This umbrella review aims to critically appraise the quality of evidence and the main clinical outcomes of available systematic reviews (SRs) on MARPE. An extensive search was carried out in five electronic databases (PubMed-Medline, Cochrane Database of SRs, Scielo, Web of Science, and LILACS) until December 2021. The methodological quality was appraised using the A Measurement Tool to Assess SRs criteria 2 (AMSTAR2). The primary outcome was the methodological quality of SRs. Overall, four SRs were included and analyzed, one of high methodological quality, one of low and two of critically low. Despite the verified methodological constraints, MARPE seems to present significant clinical changes when compared to conventional RPE, SARPE or controls and less adverse clinical outcomes. The quality of evidence produced by the available SRs was not favorable. Future high standard SRs and well-designed clinical trials are warranted to better clarify the clinical protocols and outcomes success of MARPE.

Midpalatal Suture Density as a Function of Sex and Growth-Pattern-Related Variability via CBCT Evaluations of 392 Adolescents Treated with a Rapid Maxillary Expander Appliance

Background and objectives. This paper aimed to evaluate the changes in mean bone density values of the midpalatal suture (MPS) in 392 young patients treated with a rapid palatal expander (RPE) appliance, depending on sex and vertical and sagittal skeletal patterns. Materials and Methods. Evaluations were performed using a low-dose protocol for cone beam computed tomography scans at T0 (preoperative) and T1 (1 year after the beginning of the therapy). The region of interest was used to calculate bone density in Hounsfield units (HU) for the area between the maxillary incisors. Results. CBCT scan data of 196 females and 196 males (mean age of 11.7 years) showed homogeneous and similar density values of the MPS at T0 (550.17–563.70 HU) and T1 (541.92–553.85 HU). Class III skeletal individuals showed significantly higher BD than the Class II group at T0, but not at T1. Females showed significant and substantially higher BD than males at T0 and T1. No significant differences were found between the other groups and between the two time points in terms of the bone density values of the MPS. Conclusions. Females and the Class III group showed significantly higher bone density values than males and Class II, respectively. No statistically significant differences were found from T0 to T1 in any groups, suggesting that a similar rate of suture reorganization occurs after the use of an RPE, causing reorganization and bone deposition along the MPS.