Microimplant-assisted Rapid Palatal Expansion Research Articles

Tooth-Bone-Borne vs Bone-Borne Rapid Maxillary Expanders on Dentoskeletal Changes.

This study compared the insertion and thickness of the cortical bone, the parallelism of the midpalatal suture, and the skeletal transverse dimension using a microimplant-assisted rapid palatal expansion (MARPE) with those produced by bone-anchored maxillary expander (BAME) in adults. The sample comprised 18 patients (mean age, 29.9±9.4 years) selected for the MARPE group and 18 (mean age 24.8±6.8 years) selected for the BAME group. Cone-Beam computed tomography scans taken just before and after the expansion. After treatment, there was a significant palatal depth decrease. In addition, maxillary and mandibular width were increased in both groups. Regarding the cortical bone insertion and cortical bone width, it is shown an increase in both groups but those changes are not significant. However, the anterior suture opening effect occurs more frequently in the BAME than in the MARPE device. There are no differences in the frequency of opening of the midpalatal suture in the cases treated with MARPE and BAME, in both cases the most frequent opening morphology is parallel, independently of midpalatal suture maturation. There are no differences in the use of MARPE or BAME in the parallelism of the middle palatal suture, the cortical bone insertion, and thickness according to the maturation stages of the midpalatal suture but significantly increases the transverse dimensions of the maxillary skeleton.

Skeletal and dentoalveolar effects of different types of microimplant-assisted rapid palatal expansion.

To evaluate the following null hypothesis: the skeletal and dentoalveolar expansion patterns in the coronal and axial planes are not different with two different types of microimplant-assisted rapid palatal expansion (MARPE) systems. Pretreatment (T0) and post-MARPE (T1) cone-beam computed tomography (CBCT) images of 32 patients (14 males and 18 females; mean age, 19.37) were analyzed. We compared two different MARPE systems. One MARPE system included the maxillary first premolars, maxillary first molars, and four microimplants as anchors (U46 type, n = 16), while the other included only the maxillary first molars and microimplants as anchors (U6 type, n = 16). In the molar region of the U6 and U46 groups, the transverse expansion at the midnasal, basal, alveolar, and dental levels was 2.64, 3.52, 4.46, and 6.32 mm and 2.17, 2.56, 2.73, and 5.71 mm, respectively. A significant difference was observed in the posterior alveolar-level expansion (p = 0.036) and posterior basal-bone-level expansion (p = 0.043) between the groups, with greater posterior skeletal and alveolar expansion in the U6 group. Compared with the U46 group, the U6 group showed greater posterior expansion at the alveolar and basal-bone levels, with an almost parallel split. Both groups showed a pyramidal expansion pattern in the coronal view.

Evaluation of palate-related factors of the effectiveness of microimplant-assisted rapid palatal expansion in late adolescents and adults.

This study investigated the factors of the effectiveness of microimplant-assisted rapid palatal expansion (MARPE) in late adolescents and adults, such as age, midpalatal suture maturation (MPSM) stage, palate length (PL), palatal index (PI), and midpalatal bone thickness (MBT), and at each microimplant position, the palate bone thickness (PBT), the nasal cortical bone thickness (CoTN), the cancellous bone thickness (CaT), and the palate cortical bone thickness (CoTP) were evaluated. Cone-beam computed tomography (CBCT) images of 50 patients (mean, 23.30 ± 7.03years; range, 16-51years) treated with MARPE were evaluated. Maxillary expansion ratio (MER) was used to assess the MARPE effectiveness and grouped patients into low and high MER groups according to the mean of MER. MER was the ratio of maxillary expansion width to MARPE screw expansion measured in CBCT images. Thet-test was used to analyze the differences between the low and high MER groups. The Pearson correlation test was performed to investigate the correlation between MER and age, MPSM stage, PL, PI, MBT, PBT, CoTN, CaT, and CoTP. Age, MPSM stage, and MBT in regions 18mm and 21mm behind the incisor foramen correlated negatively with MER ([Formula: see text], - 0.390, - 0.386, and - 0.335, respectively, all [Formula: see text]), whereas PBT and CoTN of anterior microimplant positions correlated positively with MER ([Formula: see text] and 0.418, respectively, all [Formula: see text]). No correlation was observed between other variables and MER. MARPE effectiveness decreased as age and midpalatal suture maturation stage increased, respectively. Thinner midpalatal suture bone in regions 18mm and 21mm behind the incisor foramen, thicker palate bone, and nasal cortical bone of anterior microimplant positions were related to more effective MARPE. In patients with older chronological age and later MPSM stages, MARPE effectiveness might be unsatisfactory. Clinicians should carefully evaluate the palate bone thickness before MARPE treatment.

Analysis of factors associated with the success of microimplant-assisted rapid palatal expansion

Success-related factors of microimplant-assisted rapid palatal expansion (MARPE) were evaluated, including age, palatal depth, suture, and parassutural bone thickness, suture density and maturation, and the relation to corticopuncture (CP) technique, as well as skeletal and dental effects. Sixty-six cone-beam computed tomography scans were analyzed before and after rapid maxillary expansion procedures in 33 patients aged 18-52 years for both sexes. The scans were generated in digital imaging and communications in medicine file format and analyzed in the multiplanar reconstruction of the regions of interest. Palatal depth, suture thickness, density and maturation, age, and CP were assessed. To evaluate dental and skeletal effects, the sample was divided into 4 groups: successful MARPE (SM), SM+ CP technique (SMCP), failure MARPE (FM), and FM+ CP (FMCP). Successful groups presented more skeletal expansion and dental tipping than failure groups (P<0.05). The mean age of the FMCP group was significantly higher than the SM groups; suture and parassutural thickness significantly related to the success, and patients who received CP showed a success rate of 81.2% compared with 33.3% in the no CP group (P<0.05). Suture density and palatal depth did not show a difference between the success and failure groups. Suture maturation was higher in SMCP and FM groups (P<0.05). Older age, thin palatal bone, and higher stage of maturation can influence the success of MARPE. CP technique in these patients appears tohave a positive impact, increasing the chance of treatment success.

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.

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.

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.

Does MARPE therapy have effects on intracranial pressure? a clinical study

BackgroundWe aimed to evaluate possible intracranial pressure (ICP) changes caused by screw activations during active microimplant-assisted rapid palatal expansion (MARPE) therapy of post-pubertal individuals by measuring the optic nerve sheath diameter (ONSD) under ultrasonography (US) guidance.MethodsThis study’s participants comprised 15 patients (7 males, 8 females) with posterior crossbite and a mean age of 16.7 years (14.25–20.08 years). The Maxillary Skeletal Expander (MSE) appliance was used to perform MARPE in all patients. Their vital signs (heart rate, mean arterial pressure (MAP), and peripheral oxygen saturation (SpO2)) were recorded. The ONSD was measured by US immediately before the first screw activation (T0), and the measurements were repeated 1 min (T1) and 10 min (T2) after the first activation. In the last session of active MARPE therapy, the same measurement protocol was performed as in the first activation session (T3, T4, and T5). The patients’ perceptions of pain during the screw activation were also noted at T1 and T4 using a four-category verbal rating scale (VRS-4). The significant differences among different time intervals performed with the Friedman test (for all tested variables; SpO2, MAP, Heart Rate, VRS-4 and ONSD). Spearman correlation test was used for VRS-4 and ONSD comparisons. The statistical significance level was accepted as p < 0.05.ResultsThe ONSD values ​​(T1 and T4) relatively increased within 1 min after screw activation but did not reach a statistically significant level (p > 0.05). There was also no significant difference between the initial (T0) and the final (T5) ONSD values ​​during the active MARPE therapy (p > 0.05).ConclusionThere is no changes or alterations in intracranial pressure in late adolescents during active MARPE therapy.

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.

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.

Three-dimensional craniofacial changes with maxillary expansion in young adult patients with different craniofacial morphology

Objectives: Skeletally mature patients with transverse deficiency are best treated with surgically assisted rapid palatal expansion (RPE) procedure. Recent studies have shown that microimplant-assisted RPE (MARPE) appliances can be effective in achieving skeletal expansion in young adults. This retrospective study aimed to evaluate the skeletal and dental alveolar changes in response to treatment with MARPE appliances in three types of anteroposterior skeletal malocclusions using cone-beam computed tomography (CBCT) scans. Material and Methods: Seventy-eight subjects diagnosed with maxillary transverse deficiency and treated with the MARPE appliance (mean age of 22.9 ± 4.2 years) were divided into skeletal Class I, II, and III malocclusions with 26 subjects in each group. Pre- and post-treatment CBCT scans were used for superimposition to examine the skeletal and dentoalveolar changes following maxillary expansion treatment. Results: Significant lateral separation of the maxilla was found at the levels of the nasal floor, interzygomatic bones, and the inferior palatine margin of the alveolar process (P &lt; 0.05) in the whole sample. Most of the sagittal and vertical variables change significantly in the whole sample and each studied group separately. Intergroup comparisons revealed no significant differences among the three skeletal classes except for the left frontozygomatic angle, left maxillary inclination angle, and torque in the first and second premolars. In Class III patients, the maxilla moved forward significantly in most of the cases (eight of 26 cases) (0.88°, P &lt; 0.05) and the mandible moved downward and backward improving the anteroposterior skeletal relationship. Significant differences were also found in the vertical measurements (N-Me, MMP, and MP/SN, P &lt; 0.05) in all three types of anteroposterior malocclusions. Conclusion: Maxillary expansion with the MARPE appliance in young adult patients induced different skeletal and dentoalveolar changes in the anteroposterior and vertical dimensions in each skeletal malocclusion with no significant difference among the three skeletal classes.

Modified Hyrax for Microimplant-Assisted Rapid Palatal Expansion

Temporary anchorage device-assisted rapid maxillary expansion has widened the horizon to treat adults having maxillary transverse deficiency without any surgical procedure. Three-dimensional custom modifications have also been developed, but they can be expensive. A modification of Hyrax screw with the use of lingual sheaths is suggested for microimplant-assisted rapid palatal expansion, which can be an easy to fabricate in-office and economical option.

Three-dimensional evaluation of skeletal and dental effects of treatment with maxillary skeletal expansion

The objective was to determine the skeletal and dental changes with microimplant assisted rapid palatal expansion (MARPE) appliances in growing (GR) and nongrowing (NG) patients using cone-beam computed tomography and 3-dimensional imaging analysis. The sample consisted of 25 patients with transverse maxillary discrepancy treated with a maxillary skeletal expander, a type of MARPE appliance. Cone-beam computed tomography scans were taken before and after maxillary expansion; the interval was 6.0 ± 4.3 months. The sample was divided into GR and NG groups using cervical vertebral and midpalatal suture maturation. Linear and angular 3-dimensional dentoskeletal changes were assessed after cranial base superimposition. Groups were compared with independent-samples t test (P<0.05). Both groups displayed marked transverse changes with a similar ratio of skeletal to dental transverse changes and parallel sutural opening from the posterior nasal spine-anterior nasal spine; a similar amount of expansion occurred in the anterior and the posterior regions of the maxilla. The maxilla expanded skeletally without rotational displacements in both groups. The small downward-forward displacements were similar in both groups, except that the GR group had a significantly greater vertical displacement of the canines (GR, 1.7 ±1.0 mm; NG, 0.6 ± 0.8 mm; P= 0.02) and anterior nasal spine (GR, 1.1 ± 0.6 mm; NG, 0.5 ± 0.5 mm; P= 0.004). Treatment of patients with MARPE appliance is effective in GR and NG patients. Although greater skeletal and dental changes were observed in GR patients, a similar ratio of skeletal to dental transverse changes was observed in both groups.

Age-dependent effects of transverse maxillary deficiency treated by microimplant-assisted rapid palatal expansion: A prospective cone-beam computed tomography study

This study investigated the results of maxillary discrepancy treated by microimplant-assisted rapid palatal expansion (MARPE) at different ages. Sixty patients (aged 11.0-34.1 years; 23 male and 37 female) were treated by MARPE. Cone-beam computed tomography scans and dental casts were taken before and after expansion. The data were compared among 4 age groups: early adolescents (aged 11-14 years), late adolescents (aged 15-19 years), young adults (aged 20-24 years), and old adults (aged 25-34.1 years). The success rates of midpalatal suture separation were 100%, 100%, 88.2%, and 85.7% for early adolescents, late adolescents, young adults, and old adults, respectively. Palatal sutures at the level of the first molar were expanded by 4.02 mm, 3.48 mm, 2.63 mm, and 2.10 mm, corresponding to 66.7%, 58.1%, 42.0%, and 37.9% of the total dental expansion. Significant differences were found in the amounts of palatal suture expansion and the ratio of skeletal dental expansion between patients aged<20 years and patients aged ≥20 years (P<0.05). Skeletal expansion constituted 69.4%, 51.3%, 39.0%, and 29.8% of the total screw expansion. Except for the comparison between young adults and old adults, there were significant differences between groups for the ratio of skeletal screw expansion (P<0.05). The midpalatal suture can be expanded by MARPE more easily in patients<20 years of age than in patients ≥20 years of age. The ratio of skeletal screw expansion decreases as age increases.

Short-term effects of microimplant-assisted rapid palatal expansion on the circummaxillary sutures in skeletally mature patients: A cone-beam computed tomography study

This study aimed to investigate the short-term effects on the circummaxillary sutures induced by microimplant-assisted rapid palatal expansion (MARPE) in skeletally mature patients. Cone-beam computed tomography (CBCT) images of preexpansion (T0) and postexpansion (T1) of 23 patients (mean age, 20.9±3.65years) treated with MARPE were evaluated. The T0 and T1 CBCT images were reoriented and superimposed on the basis of the anterior cranial base, using OnDemand3D software (Cybermed, Seoul, Korea). Then, width changes of 9 circummaxillary sutures (frontonasal, frontomaxillary, frontozygomatic, nasomaxillary, zygomaticomaxillary, intermaxillary, midpalatal, zygomaticotemporal, and pterygopalatine sutures) were measured on 1 section of each patient's T0 and T1 CBCT images. In addition, correlation coefficients between changes in the midpalatal sutures, the amount of appliance activation, age, and the changes in other circummaxillary sutural widths were also calculated. Statistically significant (P<0.05) width increases were found in all 9 circummaxillary sutures. The changes in midpalatal suture at the maxillary central incisor level positively correlated with the intermaxillary sutures at the anterior nasal spinelevel, midpalatal sutures at the posterior nasal spine level, and frontomaxillary sutures (P<0.05). In addition, the changes in the midpalatal sutures at the posterior nasal spine level also positively correlated with the changes in the intermaxillary sutures at the anterior nasal spine level, frontomaxillary sutures, and medial pterygopalatine sutures (P<0.05). All 9 circummaxillary sutural widths increased in skeletally mature patients immediately after MARPE. The greatest increases in width were measured in the midpalatal sutures and the intermaxillary sutures, followed by the frontomaxillary sutures.

Orthodontic Correction of Insufficient Posterior Overjet with Microimplant-Assisted Rapid Palatal Expansion

Transverse maxillary deficiency is often characterized by insufficient posterior overjet or posterior cross bite and anterior crowding. However, arch expansion in adult patients has been considered to be problematic owing to its possible periodontal side effects, such as gingival recession and bone dehiscence. On the other hand, nonsurgical maxillary expansion of the palatal bone in young adults has been demonstrated to correct transverse maxillary deficiency. This report describes the case of an 18-year-old patient with mild transverse maxillary deficiency accompanied by crowding who underwent microimplant-assisted rapid palatal expansion (MARPE). Using microimplant-assisted rapid palatal expansion allowed relief of crowding and correction of the patient’s insufficient posterior overjet. The supra-erupted upper second molars were extracted and replaced with the upper third molars. This report demonstrated that the combined use of MARPE could be an effective manner to treat adult patients with maxillary transverse deficiency. However, long-term stability should be observed.

Custom fabrication of cast splint microimplant-assisted rapid palatal expansion appliances for treatment of maxillary deficiency in young adults

Background: The objective of this article was to illustrate the process in the fabrication of a custom cast splint Microimplant-Assisted Rapid Palatal Expansion (MARPE) appliance for treatment of maxillary deficiency in young adults. Findings: The fabrication of a custom-made MARPE appliance allows the casting base to design according to the shape of the patient’s palate close to the palatal mucosa. In this new design, one end consists of a casting body, inserting hole, and teeth retention device (circumferential rings) connected to the other end by a jackscrew. Connection of all parts in the integral casting unit increases the strength of the expansion appliance and avoids distortion, deformation, or damage to the palatal mucosa due to increased resistance from the oromaxillofacial area. Conclusion: This custom design can improve the clinical outcome of maxillary expansion, especially in patients with narrow and high-arched palates.

Miniscrew-assisted rapid palatal expansion (MARPE) protocols applied in different ages and stages of maturation of the midpalatal suture: cases report

Objective: To evaluate the Microimplant-assisted Rapid Palatal Expansion (MARPE), considered an alternative to surgical interventions for disjunction of the midpalatal suture in adolescent patients and young adults with maxillary transverse deficiency. The stage of ossification of the midpalatal suture, bone quality and adequate activation protocols are factors that can influence the quantity and quality of the orthopedic separation. Methodology: This paper demonstrates the application of MARPE in an unfavorable case report, of an adult patient with total crossbite, in an advanced stage of fusion of the palatine and maxillary processes, with poverty in the posterior bone volume, in comparison with the same therapy in an adolescent at an earlier stage of sutural maturation. In both cases, after tomographic examinations and oral scanning, the installations and recommended activation protocol were performed. These were not sufficient in the case of the adult patient, and generated side effects that, to be overcome, required changes in activations and additional maneuvers. Results: The application of MARPE may require clinical versatility to adopt differentiated protocols in relation to chronological age, bone thickness and sutural ossification stage. Conclusion: In the end, new computer tomography scans and a clinical examination showed satisfactory results in both patients. In the unfavorable case, the opening of the midpalatal suture occurred at more modest levels, but it was sufficient to correct the posterior crossbite.

Effect of micro-implant assisted rapid palatal expansion in patients with different radiographic stages of mid-palatal suture maturation

Objective: To evaluate the effect of micro-implant assisted rapid palatal expansion (MARPE) in patients with different radiographic stages of midpalatal suture maturation. Methods: Twenty-eight patients [7 males and 21 females; age (15.5±5.5) years] with maxillary transverse deficiency were selected in the Department of Orthodontics, Hospital of Stomatology, Jilin University from February 2017 to October 2019. According to the fusion of the midpalatal suture, the patients were divided into two groups: 10 patients [3 males and 7 females; age (19.9±6.9) years] were in fusion group and 18 patients [4 males and 14 females; age (13.0±2.4) years] were in non-fusion group. Each patient had cone-beam CT (CBCT) images taken immediately after the placement of micro-implants (T1) and the completion of maxillary expansion (T2). The CBCT images were analyzed using the Dolphin Imaging software to evaluate the amount of midpalatal expansion and the percentages of bony expansion, etc. Statistical analysis was carried out to compare the two groups. Results: After MARPE treatment, the amount of sutural expansion in fusion group was (3.23±1.45) mm while that in non-fusion group was (4.97±1.47) mm (P<0.05). There was a statistically significant difference in the percentages of bony expansion efficiency between the non-fusion group (71±20)% and the fusion group (46±18)% (P<0.05). Conclusions: Bony expansion efficiency was affacted by the radiographic stages of midpalatal suture maturation.

The role of micro-implant-assisted rapid palatal expansion (MARPE) in clinical orthodontics — a literature review

Abstract A maxillary transverse deficiency is a common craniofacial problem. Rapid palatal expansion (RPE) has been traditionally considered for the treatment of children and young adolescents, but this is not applicable in late adolescents or adults due to the ossification of facial sutures. A surgically assisted rapid palatal expansion (SARPE) was initially advocated for this group of patients, but the surgical procedure is associated with morbidity. As temporary anchorage devices (TADs) have been recently and popularly applied in clinical orthodontics, micro-implant-assisted rapid palatal expansion (MARPE) has been employed to facilitate maxillary expansion in skeletally mature patients. There have been various proposed MARPE designs and the outcomes appear promising. The aim of the present article is to discuss the role of MARPE in clinical orthodontics by reviewing its background, design, indications, treatment effects, stability, and limitations in the current literature. The treatment effects of two types of MARPE, bone-borne and tooth-bone-borne (hybrid), will be individually assessed.