Alternate Rapid Maxillary Expansion Research Articles

Comparison of the effectiveness of skeletal and tooth-borne protraction methods with or without alternate rapid maxillary expansion and constriction protocol in patients with Class III malocclusion

Comparison of the effectiveness of skeletal and tooth-borne protraction methods with or without alternate rapid maxillary expansion and constriction protocol in patients with Class III malocclusion

Impact of tonsillectomy on the efficacy of Alt-RAMEC/PFM treatment protocols in children with class III malocclusion and tonsillar hypertrophy: protocol for a cluster randomised controlled trial

IntroductionOrthodontic treatment using face mask protraction combined with an alternate rapid maxillary expansion and constriction/protraction face mask (Alt-RAMEC/PFM) protocol is effective in the early treatment of patients with class III...

Effect of Slow Maxillary Expansion and Alternative Rapid Maxillary Expansion Protocols on Airway Volume in Cleft Palate Cases: A Cone Beam Computed Tomography Based Study.

A total of 22 patients with cleft palate aged 8 to 12 years were selected and categorized into two groups: the first group was treated with alternate rapid maxillary expansion and constriction (Alt-RAMEC) using an expander with differential opening (EDO) and facemask, while the second group was treated using slow maxillary expansion (SME) using an EDO. Finally, the pharyngeal airway volume in the two groups was compared using cone beam computed tomography (CBCT). CBCT scans were performed before expansion and six months following the expansion. Alveolar crest level, maxillary breadth, nasal cavity width, arch width, inclination of the molar teeth, buccal and palatal alveolar bone thickness, and maxillary alveolar width were all assessed. Paired t-tests (p=0.05) were applied to compare interphase data. The two groups showed a non-significant difference in terms of nasopharyngeal volume (cm3), oropharyngeal volume (cm3), and overall pre- and post-treatment results (p>0.005). Results of comparison of pre- and post-treatment periods in the Alt-RAMEC group revealed a significantly higher cleft volume (cm3) (p=0.001). Results of comparison of pre- and post-treatment periods in the SME group revealed a substantial rise in cleft volume (cm3) (p=0.003).Results from a comparison of the cleft volume (cm3) between the two study groups pre- and post-intervention revealed a non-significant difference (p=0.200 and 0.054, respectively).

Temporomandibular joint disc position and shape in patients submitted to two protocols of rapid maxillary expansion and face mask therapy: A randomized clinical trial.

The objective of this prospective study was to assess possible changes in the position and shape of the temporomandibular joint (TMJ) articular disc in patients treated with two protocols of rapid maxillary expansion (RME) and face mask (FM) therapy. A sample of 88 patients with Class III or Class III subdivision malocclusions, aged between 6 and 13 years, were consecutively selected and divided into three groups (G): G1-34 patients were treated with RME, followed by FM therapy; G2-34 patients were treated using RME according to modified alternate rapid maxillary expansion and constriction (ALT-RAMEC) protocol, followed by FM therapy. These treated groups were randomly (1:1 allocation ratio) distributed according to the two treatment protocols. G3 - Control Group - 20 untreated patients were followed. Magnetic resonance imaging (MRI) TMJs were obtained before (T1) and after (T2) a treatment period or follow-up. McNemar test, Fisher's exact test and intra- and inter-observer concordance (K) were performed (p ≤ .05). There were no statistically significant differences in the baseline cephalometric variables at T1 between the groups. There were statistically significant differences between the groups (p < .001) in relation to the disc shape in T1, since G1 (8 TMJs -11.76%) presented higher occurrences of altered forms in comparison with G2 (no changes). No significant differences were observed in disc position CM and OM (G1 - p > .999; G2 - p = .063; G3 - p = .500) and shape (G1 - p > 0.999; G2 - p = .250; G3 - not calculable), between T1 × T2, in any of the groups studied. The two treatment protocols did not have adverse effects on the position and shape of the TMJ disc, in a short-term evaluation.

Comparison of Rapid Maxillary Expansion and Alternate Rapid Maxillary Expansion and Constriction Protocols with Face Mask Therapy.

This study compared dentoskeletal and soft tissue changes with face mask (FM) therapy. Rapid maxillary expansion (RME) and alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocols were used with the two different types of expansion appliance, and their effects on the treatment outcome were investigated. The study consisted of 79 (37 and 42 patients in the RME and Alt-RAMEC groups with FM, respectively) patients who had received FM treatment. The effects of the RME/FM (20 female, 17 male) and Alt-RAMEC/FM (14 female, 28 male) protocols were evaluated using lateral cephalometric films. The chronological ages of the RME/FM and Alt-RAMEC/FM groups were 11.58 and 11.99 years, respectively. In addition, both groups were divided into two subgroups based on the design of the expansion appliance (Spolyar or full coverage type). Differences in all parameters were analyzed using Student's t-tests. The maxilla significantly moved forward in both the RME/FM and Alt-RAMEC/FM groups (p<0.001). No significant skeletal differences were observed between the groups. Sagittal movement of the upper incisors significantly increased, and the lower incisors significantly retruded in both groups. While similar skeletal changes were found between the Spolyar and full-coverage appliance groups, the upper incisors protruded significantly more in the full-coverage type. RME/FM and Alt-RAMEC/FM therapies were found to be efficient for maxillary protraction and resulted in similar skeletal changes. A full-coverage expansion appliance produced a more upper incisor protrusion than a spherical-type appliance.

Comparison of changes in the nasal cavity, pharyngeal airway, and maxillary sinus volumes after expansion and maxillary protraction with two protocols: Rapid palatal expansion versus alternate rapid maxillary expansion and constriction.

To evaluate and compare a series of volume changes in the nasal cavity (NC), nasopharynx, oropharynx, and maxillary sinuses (MS) in growing Class III patients after either rapid palatal expansion (RPE) or alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy, by using conebeam computed tomography (CBCT). Forty growing Class III patients were retrospectively selected and divided into two matched groups: RPE/FM (14 females, 6 males; mean age, 9.66 ± 1.23 years) and Alt-RAMEC/FM groups (14 females, 6 males; mean age, 10.28 ± 1.45 years). The anteroposterior and vertical displacements of Point A, the volumes of the NC, nasopharyngeal, oropharyngeal, and MS were measured at different time points: pretreatment (T1), postexpansion (T2), and postprotraction (T3). Both groups demonstrated significant maxilla advancement (by 1.3 mm) during expansion, with a statistically significant intergroup difference during protraction (RPE/FM, 1.1 mm; Alt-RAMEC/FM, 2.4 mm; p < 0.05) and throughout the treatment (RPE/FM, 2.4 mm; Alt-RAMEC/FM, 3.7 mm; p < 0.05). NC and nasopharyngeal airway volumes increased significantly in both groups after expansion, protraction, and treatment. The oropharyngeal and MS volumes increased in both groups after protraction and post-treatment. However, no volumetric differences were observed between the two groups. There was no significant difference in airway volume changes, including NC, nasopharyngeal, oropharyngeal airway, and MS, between RPE/FM and Alt-RAMEC/FM groups at different time points. Although there was significantly more forward movement after protraction in the Alt-RAMEC/FM group, the difference was deemed too small to be clinically relevant.

Assessment of influence of facemask treatment with skeletal anchorage on the temporomandibular joint using magnetic resonance imaging: a preliminary study.

The aim of the study was to investigate the influence of facemask treatment with skeletal anchorage on the temporomandibular joint (TMJ) using magnetic resonance imaging (MRI), in patients with Class III malocclusion, accompanied by maxillary retrusion. Fifteen patients with a mean age of 12.1±1.43 years were included in the study. All patients were treated using facemask with skeletal anchorage after eight weeks of Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) protocol. Magnetic resonance imaging was performed before and immediately after facemask treatment for TMJ evaluation. Disc position, condylar translation, degenerative changes of the condyles, and joint effusion were evaluated. To assess whether the alterations associated with the treatment were statistically significant, McNemar and marginal homogeneity tests were used. After facemask treatment, a statistically significant change was observed in the disc position (an anterior disc displacement with/without reduction in five TMJs) (p<0.05). The alteration in the condylar translation was not statistically significant (p>0.05). This treatment did not cause degenerative changes of the condyles or effusion in any of the TMJs. Facemask treatment with skeletal anchorage following the Alt-RAMEC protocol had a minimal influence on the TMJ, only by means of disc position, which was not negligible. Long-term results of such treatment are required for following up the changes observed in the TMJs.

Effect of Maxillary Expansion Treatment Protocols On Maxillary Sinus Volume, Pharyngeal Airway Volume, and Hyoid Bone Position: A Prospective, Cone Beam Computed Tomography (CBCT) Study

Aim: This study aimed to investigate the changes in maxillary sinus volume, pharyngeal airway volume, and hyoid bone position in patients treated with Rapid Maxillary Expansion (RME) and Alternate Rapid Maxillary Expansion and Constriction (AltRaMEC) – Facemask therapy and compare between the groups. Materials and Methods: The records of 15 patients between the age group of 8-14 years with Class I and Class III malocclusion were collected, and the patients were assigned into two groups. The first group comprised of 8patients (4 girls and 4 boys) who were treated with Rapid Maxillary Expansion. The second group comprised 7 patients (5 boys and 2 girls) treated with expansion devices using Alt-RaMEC protocol followed by maxillary protraction using a facemask. Pre and post-treatment CBCT scans were obtained and analyzed for changes in the pharyngeal airway, maxillary sinus volume, and hyoid bone position. The maxillary sinus volume was calculated in 3 dimensions by measuring the craniocaudal height, anteroposterior depth, and mediolateral width. Measurements were taken before and after the procedure to compare the groups and between the groups. The data were analyzed using Paired t-test and an Independent t-test. Results: In the RME group, a significant increase in the total maxillary sinus volume (mean difference = 520±576.57mm3), especially in the craniocaudal height, was seen, but no changes were noted in the pharyngeal airway and hyoid position. The AltRAMEC group showed a statistically significant increase in the maxillary sinus volume (anteroposteriorly) and nasopharyngeal volume with a p-value &lt;0.005. Comparing the maxillary sinus volume changes in RME and AltRAMEC groups showed a statistically significant increase in the volume of the maxillary sinuses in both groups, significantly higher in the RME group. Conclusion: RME and AltRAMEC protocol followed by facemask therapy caused a significant increase in the maxillary sinus volume, while no changes were noted in the nasopharynx, oropharynx, hypopharynx, and hyoid bone position. While comparing the treatment effects between the groups, RME showed a greater increase in maxillary sinus volume (p &lt; 0.05), specifically in the anteroposterior dimension. Since there are no changes in airway volume and hyoid position with the skeletal expansion protocols, there will be no difference in nasal resistance to airflow.

Soft tissue evaluation after maxillary protraction with RPE or with the ALT-RAMEC protocol : Acontrolled 3D study.

To evaluate soft tissue changes following maxillary protraction with different expansion protocols using three-dimensional (3D) stereophotogrammetry. Pretreatment (T0) and postprotraction (T1) stereophotogrammetry and lateral cephalometric images of skeletal classIII patients were included in this retrospective study. In all, 32patients were treated either with acombination of rapid palatal expansion and facemask (RPE/FM; n = 16; mean age: 9.94 ± 0.68years) or with alternate rapid maxillary expansion and constriction together with afacemask (Alt-RAMEC/FM; n = 16; mean age: 9.74 ± 1.35years). As acontrol group16 untreated patients were recruited (mean age: 9.46 ± 0.8years). For superimpositioning of the 3D images taken at T0 and T1, the face was divided into defined regions and 3D and differences between the groups were evaluated using 3‑matic software (Materialise Europe, Leuven, Belgium). Cephalometric analyses were also performed. While the increases in the cephalometric parameters SNA and ANB were significantly greater in the treatment groups, the value for SNB also increased in the control group (p < 0.05). The results of the stereophotogrammetry analyses demonstrated that the mean changes in the RPE/FM and in the Alt-RAMEC/FM groups were significantly different for the midface compared to the control group (0.33 ± 0.26 mm, 0.3 ± 0.31 mm, 0.1 ± 0.18 mm). The maximum positive, negative, and mean changes were also significantly different between the treatment and control groups for the upper lip (p < 0.05). For the lower lip and the chin significant backward movements in the RPE/FM as well as in the Alt-RAMEC/FM group (-1.06 ± 1.26 mm, -0.68 ± 0.45 mm) were observed, while the control group (0.09 ± 0.53 mm) presented changes in the opposite direction. Regarding soft tissue changes, no significant differences were found between the RPE/FM and Alt-RAMEC/FM groups. Both treatment protocols improved the soft tissue profile due to aforward movement of the midface and the upper lip, and abackward movement of the lower lip and chin, compared to the control group.

Effect of alternate rapid maxillary expansion and constriction on pharyngeal airway– A case report

The Alt-RAMEC protocol was introduced by Liou in the year 2005. It allows for sutural mobilisation by opening and closing the RME screw for 7-9 weeks. Maxillary protraction after the use of Alt-RAMEC (Alternate Rapid Maxillary Expansion and Contraction) protocol is an efficient method for early treatment skeletal Class III malocclusion. This case report shows the results of the using hyrax bonded maxillary expander with Alt-RAMEC protocol to treat a maxillary hypoplasia Class III malocclusion. A 10-year-old patient with skeletal class III malocclusion with anterior as well as unilateral posterior crossbite was treated using this protocol. CBCT scans were taken before and after expansion. These CBCT scans were used for assessing and analyzing the airway tissue changes that have occurred after using Alt-RAMEC protocol. The objective of this case report is to assess airway changes after using Alt-RAMEC protocol.

Does Maxillary Protraction with Alt-RAMEC Protocol Affect Inferior Sclera Exposure? A Controlled 3dMD Study.

The purpose of this controlled retrospective study was to measure and evaluate the inferior sclera exposure changes using 3dMD stereophotogrammetric images in a prepubertal Class III patient sample that underwent maxillary protraction with alternate rapid maxillary expansions and constrictions protocol followed by facemask. The study group included 15 prepubertal patients (mean age: 9.85 ± 1.44 years) with Class III malocclusion due to maxillary retrognathism. Nine weeks of alternate rapid maxillary expansions and constrictions protocol was followed prior to 7 months of face mask treatment and 3 months of retention with Bionator. Pretreatment (T0) and post-retention (T1) lateral cephalometric radiographs and 3dMD images were retrieved from clinical archive. The same records were used for a control group of 15 well-matched, untreated patients (mean age: 9.4 ± 0.79 years). The distance between the upper eyelid margin and the lower eyelid margin was recorded as the overall eye height (E), and the distance between inferior limbus and the lower eyelid margin was recorded as inferior sclera exposure (S). The S : E ratio in percentage was calculated. Sella-nasion-A point angle (SNA) was used as the skeletal variable. SNA angle, right S : E, and left S : E changed significantly in both groups at T1-T0. The intergroup comparison was highly significant for SNA angle but was not significant for right and left S : E variables. The S : E ratio decreased significantly in both alternate rapid maxillary expansions and constrictions/facemask and the control groups. However, the change in S : E ratio between groups was not significant.

Comparison of the short-term effects of facemask therapy preceded by conventional rapid maxillary expansion or by an alternate rapid maxillary expansions and constrictions protocol : Aretrospective study.

We aimed to compare the short-term effects of alternate rapid maxillary expansion and constriction (Alt-RAMEC) with conventional rapid maxillary expansion (RME) followed by facemask (FM) therapy. A total of 30patients who had received facemask therapy after RME or Alt-RAMEC protocols were included in the study. The Alt-RAMEC/FM and RME/FM groups were created to be well-matched regarding cervical vertebral maturation stage and sex. In the Alt-RAMEC group (10males and 5females, 10.99 ± 1.80years), expansion screws were activated for aweek (two turns/day), then deactivated in the following week (two turns/day). The activation-deactivation protocol continued for 6 or 7weeks. In the RME/FM group (10males and 5females, 11.61 ± 1.20years), screw activation was performed according to the patients' requirements. Lateral cephalograms which had been taken at the beginning of treatment and at the end of the facemask therapy were analyzed. Intragroup and intergroup differences were statistically analyzed. Both groups showed asignificant sagittal advancement of the maxilla. However, the Alt-RAMEC/FM group showed statistically greater improvements than the RME/FM group for SNA (3.11 ± 1.79 vs. 1.45 ± 1.34, p = 0.008), ANB (4.29 ± 1.80 vs. 2.95 ± 1.19, p = 0.023), convexity (8.91 ± 4.29 vs. 5.61 ± 2.51, p = 0.016), and overjet (5.86 ± 2.29 vs. 4.61 ± 2.10, p < 0.001). The sagittal mandibular, vertical skeletal, dental, and soft tissue changes were similar between the groups (p > 0.05). The Alt-RAMEC protocol was found to be more effective in the correction of skeletal classIII malocclusion in the short term.

Early Treatment of Class III Malocclusion Using Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) Protocol with Facemask Therapy: A Case Report

Orthodontists face difficulty when it comes to treating Class III malocclusion. It is best to treat it at the growing stage with dentofacial orthopedics. Maxillary protraction using the Alternate Rapid Maxillary Expansion and Contraction (Alt-RAME) technique is an effective approach for treating skeletal Class III malocclusion at an early age. A 9-year-old female patient came to the Department of Orthodontics with a complaint of backwardly placed upper teeth and un-aesthetic dental as well as facial appearance. Intraoral examination revealed an anterior cross-bite of 1 mm. Molar relation was class III on the right side and super Class I on the left side. Slight crowding in lower arch and spacing in maxillary arch due to unerupted teeth was seen. The patient was diagnosed with Class III skeletal pattern associated with maxillary retrusion, average growth pattern, Class III molar relation on right side, super Class I molar relation on left side and a protrusive lower lip. The early treatment of such cases is essential, so that maxillary retrusion can be corrected with the help of orthopedic intervention. It was decided that the correction of skeletal Class III malocclusion will be done using Alt-RAMEC protocol along with facemask. Use of Alt-RAMEC protocol for correction of Class III malocclusion due to maxillary retrusion can help in early correction of Class III skeletal pattern and helps improving overall profile of the patient. This case report shows the result of using a hyrax bonded maxillary expander with Alt-RAMEC protocol along with a facemask to treat a Class III malocclusion associated with maxillary hypoplasia. A 9-year-old patient with skeletal class III malocclusion and anterior crossbite was treated using this protocol.

A retrospective long-term comparison of early RME-facemask versus late Hybrid-Hyrax, alt-RAMEC and miniscrew-supported intraoral elastics in growing Class III patients

To compare the long-term dentoskeletal effects of early treatment with banded or bonded RME (Rapid Maxillary Expansion)-Face Mask (RME-FM) versus late treatment with bonded Hybrid-Hyrax, alt-RAMEC (Alternate Rapid Maxillary Expansion and Contraction) and intraoral Class III elastics anchored to miniscrew-reinforced-Lower-lingual-Arch (alt-RAMEC-HH-LLA) in growing, maxillary retrognathic patients. Two groups were matched at long-term follow-up retrospectively. Patients received either early RME-FM (n=16, 5 males, 11 females, age T1: 6.5±0.9 years, age T2: 15.8±2.5 years) or late alt-RAMEC-HH-LLA (n=15, 7 males, 8 females, age T1: 12.52±0.94 years, age T2: 16.8±0.9 years). Total follow-up was 9.2±2.3 years and 4.2±0.2 years respectively, including fixed appliances to compete treatment. Both treatments resulted in Class III correction except one unsuccessful case of alt-RAMEC-HH-LLA. Active maxillary protraction was 1.6±0.5years with RME-FM and 0.5 years with alt-RAMEC-HH-LLA being significantly shorter (P<0.001). Values at T2 estimation with multivariate linear regression for correlated multiple outcomes, conditional on baseline estimates, age and sex showed alt-RAMEC-HH-LLA inducing significantly more retroclined lower incisors (mean: -6.11°; 95%CI: -10.66, -1.57; P=0.01), less overbite (mean: -1.28mm; 95%CI: -1.79, -0.761; P<0.001), less maxillo (Co-A)- (mean: -4.54mm; 95%CI: -7.91, -1.16; P=0.01) mandibular (Co-Gn) (mean: -10.5mm; 95%CI: -17.45, -3.55; P=0.003) projections/size, more open gonial angle (mean: 4.93°; 95%CI: 2.27, 7.59; P<0.001), and less S-N length (mean: -5.04mm; 95%CI: -6.57, -3.51; P<0.001). Patients treated with either early RME-FM or late Alt-RAMEC-HH-LLA had comparable overall post-pubertal skeletal and overjet corrections. However, the late Alt-RAMEC-HH-LLA showed less correction of dentoalveolar compensations and in particular of the mandibular incisors. The overbite, maxillary and mandibular projection and size were lower and the gonial angle was more open.

English

The Alt-RAMEC protocol was introduced by Liou in the year 2005. It allows for sutural mobilisation by opening and closing the RME screw for 7-9 weeks. Maxillary protraction after the use of Alt-Ramec (alternate rapid maxillary expansion and contraction) protocol is an efficient method for early treatment of skeletal Class III malocclusion. This case report shows the results of using a hyrax bonded maxillary expander with the Alt-RAMEC protocol to treat a maxillary hypoplasia Class III malocclusion. A 12-year-old patient with skeletal class III malocclusion with anterior as well as the unilateral posterior crossbite was treated using this protocol. CBCT scans were taken before and after expansion. These CBCT scans were used for assessing and analysing the skeletal changes that have occurred after using the AltRamec protocol. The objective of this case report is to assess skeletal changes after using the Alt-RAMEC protocol.

Retraction: Treatment of Class III Malocclusion with Activation-Deactivation Rapid Palatal Expansion and Reverse Headgear in a Growing Patient (Alternate-Rapid Maxillary Expansion and Contraction).

[This retracts the article on p. 376 in vol. 11, PMID: 33850405.].

Does Alt-RAMEC protocol and facemask treatment affect dentoalveolar structures?

To evaluate dentoalveolar changes immediately after the alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol and facemask (FM) treatment using cone-beam computed tomography images. Cone-beam computed tomography images of 20 patients (mean age = 9.64 ± 1.3 years) who received the Alt-RAMEC protocol before FM treatment were retrieved in this retrospective study. Dental and alveolar inclinations, buccal and palatal alveolar bone thickness, and buccal and palatal alveolar bone height changes were measured before treatment (T0), after the Alt-RAMEC protocol (T1), and after FM treatment (T2). Measurements for right and left molars were performed separately. The Shapiro-Wilks test was used to assess the conformity of the parameters to the normal distribution. The paired t-test and repeated measures analysis of variance were used for normally distributed data. The Wilcoxon signed-rank test and Friedman test were used for non-normally distributed data. The Bonferroni correction was used to reduce the chances of obtaining false-positive results. Statistical significance was set at P < .05. Buccal alveolar bone thickness and alveolar bone inclinations decreased significantly from T1 to T0 and showed no significant change from T2 to T1. The total reduction T2-T0 was statistically significant. The change in palatal alveolar bone thickness was not significant T1-T0 but increased significantly for T2-T1 and T2-T0. Buccal alveolar bone height, palatal alveolar bone height, and molar inclinations increased significantly T1-T0, but there was no significant change T2-T1. The total reduction at T2-T0 was statistically significant. The results of this study revealed that the effects of the Alt-RAMEC protocol on dentoalveolar tissues were similar to the changes reported in the literature after rapid palatal expansion.

Evaluation of Alt-RAMEC With Facemask in Patients With Unilateral Cleft lip and Palate (UCLP) Using Cone Beam Computed Tomography (CBCT) and Finite Element Modeling-A Clinical Prospective Study.

Evaluate the effects of alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol on patients with unilateral cleft lip and palate (UCLP) along with maxillary protraction using cone beam computed tomography (CBCT) records and a finite element modeling (FEM) model. Twenty-five patients (aged 9-13 years) with UCLP having a GOSLON score 3 were selected for this prospective single-arm cohort study after obtaining necessary informed consent. A 9-week Alt-RAMEC protocol using a custom-made fan-shaped expansion screw was initiated, which was followed by 6-month facemask wear. Pre (T1) and posttreatment (T2) records including CBCT were taken and were evaluated for treatment changes in all 3 dimensions using paired t test. Additionally, a FEM model (ANSYS 15.0) using the Alt-RAMEC protocol was also analyzed for the displacement and stress on various craniofacial structures. Significant forward movement of the maxilla along with clockwise rotation of mandible along with statistically significant increase in lower molar height and upper incisor proclination (P < .05) was observed. CBCT evaluation showed a statistical significant decrease in buccal alveolar bone thickness and increase in molar inclination (P < .05). Finite element modeling analysis highlighted that the maximum displacement occurred at the anterior region with stresses radiating till the anterior nasal spine, zygomatic arch, and sphenoid bone. Alt- RAMEC protocol combined with facemask protraction can lead to significant maxillary advancement, with some transient decrease in buccal bone thickness noted thereby warranting long-term studies to further assess its effect on the dentofacial apparatus.

Determining the short-term effects of different maxillary protraction methods on pharyngeal airway dimensions.

This study sought to evaluate the effects of different maxillary protraction methods on the pharyngeal airway in Class III patients with maxillary retrognathia. A total of 59 individuals (31 females and 28 males) with a mean age of 11.38±1.24years were included in this study. Fifty-nine treated maxillary retrognathic patients who underwent different protraction methods were evaluated. Twenty patients treated with RME (Rapid Maxillary Expansion) made up the first group, and 20 patients treated with 5-week Alt-RAMEC (Alternate Rapid Maxillary Expansion and Constriction) protocol comprised the second group. Lastly, 19 patients on whom face masks with miniplates were applied were included in the skeletal anchorage (SA) group. Sixteen linear and four areal pharyngeal airway measurements were made on lateral cephalograms before and after treatment. Differences between the groups were assessed using analysis of variance (ANOVA) tests. The mean maxillary protraction levels were determined as 2.7, 3.69 and 4.01mm in the RME, Alt-RAMEC and SA groups, respectively. In the nasopharynx, AD1-PNS, AD2-PNS, PNS-Ba and PNS-Ho measurements revealed a significant increase in the SA group compared to the other groups (P<.05). In the oropharynx, PNS-Ep measurement increased significantly in the RME group (P<.05). In the total pharyngeal airway area, an increase was detected in the SA, Alt-RAMEC, and RME groups. The most effective protraction method in terms of pharyngeal airway dimensions, especially in the nasopharynx, is the application of the face mask with skeletal anchorage. A greater increase in vertical airway length (PNS-Ep) was observed with RME.

Relative effectiveness of facemask therapy with alternate maxillary expansion and constriction in the early treatment of Class III malocclusion

This study aimed to investigate the relative efficacy of maxillary protraction combined with a modified alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol compared with conventional protocols in the early orthopedic treatment of skeletal Class III malocclusion. A sample of 39 patients was divided into 3 groups on the basis of different interventions. Conventional facemask (FM) with splint-type intraoral devices was performed in the FM group (7 males and 5 females; mean age, 9.53±1.37years). Maxillary expansion with an activation rate of 0.5mm/d (twice a day) followed by FM therapy was applied in the rapid maxillary expansion group (RME/FM) (6 males and 6 females; mean age, 9.31±1.60years). In the Alt-RAMEC/FM group (7 males and 8 females; mean age, 10.01±1.31years), Alt-RAMEC was started simultaneously and throughout the entire course of maxillary protraction, with repetitive alternations between activation and deactivation of expanders (0.5mm/d for 7days). The patients in all groups were instructed to wear FMs for a minimum of 12h/d. Pretreatment and posttreatment lateral cephalograms were all traced and measured. The Alt-RAMEC group showed statistically more significant maxillary advancement than other groups (A-VRP, 3.87mm vs 3.04mm [RME/FM], vs 2.04mm [FM]; P<0.05). Analysis of variance did not reveal significant intergroup differences in palatal plane angulation changes (P>0.05). No pronounced mandibular clockwise rotations were noted in the Alt-RAMEC/FM group with distinct intergroup differences (P<0.05). There were more skeletal effects (88.7%) during overjet correction in the Alt-RAMEC/FM protocol. A combination of the modified Alt-RAMEC protocol with FM revealed more favorable skeletal effects compared with FM and RME/FM protocols in treating prepubertal patients with maxillary deficiency.