Activation-deactivation rapid palatal expansion and reverse headgear in Class III cases

Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children

BACKGROUND

Prominent lower front teeth (Class III malocclusion) may be due to jaw or tooth position or both. The upper jaw (maxilla) can be too far back or the lower jaw (mandible) too far forward; the upper front teeth (incisors) may be tipped back or the lower front teeth tipped forwards. Orthodontic treatment uses different types of braces (appliances) fitted inside or outside the mouth (or both) and fixed to the teeth. A facemask is the most commonly reported non-surgical intervention used to correct Class III malocclusion. The facemask rests on the forehead and chin, and is connected to the upper teeth via an expansion appliance (known as 'rapid maxillary expansion' (RME)). Using elastic bands placed by the wearer, a force is applied to the top teeth and jaw to pull them forwards and downward. Some orthodontic interventions involve a surgical component; these go through the gum into the bone (e.g. miniplates). In severe cases, or if orthodontic treatment is unsuccessful, people may need jaw (orthognathic) surgery as adults. This review updates one published in 2013.

OBJECTIVES

To assess the effects of orthodontic treatment for prominent lower front teeth in children and adolescents.

SEARCH METHODS

An information specialist searched four bibliographic databases and two trial registries up to 16 January 2023. Review authors screened reference lists.

SELECTION CRITERIA

We looked for randomised controlled trials (RCTs) involving children and adolescents (16 years of age or under) randomised to receive orthodontic treatment to correct prominent lower front teeth (Class III malocclusion), or no (or delayed) treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcome was overjet (i.e. prominence of the lower front teeth); our secondary outcomes included ANB (A point, nasion, B point) angle (which measures the relative position of the maxilla to the mandible).

MAIN RESULTS

We identified 29 RCTs that randomised 1169 children (1102 analysed). The children were five to 13 years old at the start of treatment. Most studies measured outcomes directly after treatment; only one study provided long-term follow-up. All studies were at high risk of bias as participant and personnel blinding was not possible. Non-surgical orthodontic treatment versus untreated control We found moderate-certainty evidence that non-surgical orthodontic treatments provided a substantial improvement in overjet (mean difference (MD) 5.03 mm, 95% confidence interval (CI) 3.81 to 6.25; 4 studies, 184 participants) and ANB (MD 3.05°, 95% CI 2.40 to 3.71; 8 studies, 345 participants), compared to an untreated control group, when measured immediately after treatment. There was high heterogeneity in the analyses, but the effects were consistently in favour of the orthodontic treatment groups rather than the untreated control groups (studies tested facemask (with or without RME), chin cup, orthodontic removable traction appliance, tandem traction bow appliance, reverse Twin Block with lip pads and RME, Reverse Forsus and mandibular headgear). Longer-term outcomes were measured in only one study, which evaluated facemask. It presented low-certainty evidence that improvements in overjet and ANB were smaller at 3-year follow-up than just after treatment (overjet MD 2.5 mm, 95% CI 1.21 to 3.79; ANB MD 1.4°, 95% CI 0.43 to 2.37; 63 participants), and were not found at 6-year follow-up (overjet MD 1.30 mm, 95% CI -0.16 to 2.76; ANB MD 0.7°, 95% CI -0.74 to 2.14; 65 participants). In the same study, at the 6-year follow-up, clinicians made an assessment of whether surgical correction of participants' jaw position was likely to be needed in the future. A perceived need for surgical correction was observed more often in participants who had not received facemask treatment (odds ratio (OR) 3.34, 95% CI 1.21 to 9.24; 65 participants; low-certainty evidence). Surgical orthodontic treatment versus untreated control One study of 30 participants evaluated surgical miniplates, with facemask or Class III elastics, against no treatment, and found a substantial improvement in overjet (MD 7.96 mm, 95% CI 6.99 to 8.40) and ANB (MD 5.20°, 95% CI 4.48 to 5.92; 30 participants). However, the evidence was of low certainty, and there was no follow-up beyond the end of treatment. Facemask versus another non-surgical orthodontic treatment Eight studies compared facemask or modified facemask (with or without RME) to another non-surgical orthodontic treatment. Meta-analysis did not suggest that other treatments were superior; however, there was high heterogeneity, with mixed, uncertain findings (very low-certainty evidence). Facemask versus surgically-anchored appliance There may be no advantage of adding surgical anchorage to facemasks for ANB (MD -0.35, 95% CI -0.78 to 0.07; 4 studies, 143 participants; low-certainty evidence). The evidence for overjet was of very low certainty (MD -0.40 mm, 95% CI -1.30 to 0.50; 1 study, 43 participants). Facemask variations Adding RME to facemask treatment may have no additional benefit for ANB (MD -0.15°, 95% CI -0.94 to 0.64; 2 studies, 60 participants; low-certainty evidence). The evidence for overjet was of low certainty (MD 1.86 mm, 95% CI 0.39 to 3.33; 1 study, 31 participants). There may be no benefit in terms of effect on ANB of alternating rapid maxillary expansion and constriction compared to using expansion alone (MD -0.46°, 95% CI -1.03 to 0.10; 4 studies, 131 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Moderate-certainty evidence showed that non-surgical orthodontic treatments (which included facemask, reverse Twin Block, orthodontic removable traction appliance, chin cup, tandem traction bow appliance and mandibular headgear) improved the bite and jaw relationship immediately post-treatment. Low-certainty evidence showed surgical orthodontic treatments were also effective. One study measured longer-term outcomes and found that the benefit from facemask was reduced three years after treatment, and appeared to be lost by six years. However, participants receiving facemask treatment were judged by clinicians to be less likely to need jaw surgery in adulthood. We have low confidence in these findings and more studies are required to reach reliable conclusions. Orthodontic treatment for Class III malocclusion can be invasive, expensive and time-consuming, so future trials should include measurement of adverse effects and patient satisfaction, and should last long enough to evaluate whether orthodontic treatment in childhood avoids the need for jaw surgery in adulthood.

The effect of tooth borne versus skeletally anchored Alt-RAMEC protocol in early treatment of Class III malocclusion: a single-centre randomized clinical trial

TRIAL DESIGN

This was a randomized, controlled trial designed to compare outcomes between the use of dental and skeletal anchorage, using the Face mask/Alternate Rapid Maxillary Expansion and Contraction (FM/Alt-RAMEC) protocol.

METHODS AND PARTICIPANTS

The study was carried out at Mater Dei Hospital, Malta and included prepubertal skeletal Class III malocclusion patients where the aetiology was primarily maxillary hypoplasia.

INTERVENTIONS

Two groups were assigned. Group I was treated with FM/Alt-RAMEC and group II was treated with skeletally anchored FM/Alt-RAMEC. Wear-time (WT) of the FM was monitored using TheraMon microsensors. Patients were instructed to wear the FM for 12-14 hours/day for 9 months. Changes were evaluated with lateral cephalograms and analysed with Wilcoxon and Mann-Whitney U tests. ANOVA was used to analyse the effect of gender on compliance parameters. Spearman's correlation coefficient was used to assess the correlation between compliance and skeletal changes.

OBJECTIVE

To compare the skeletal and dentoalveolar changes in patients treated with these two protocols.

OUTCOMES

The primary outcome was to assess skeletal and dentoalveolar outcomes in patients treated with skeletally anchored FM/RME and tooth-borne FM/RME; utilizing Alt-RAMEC protocol. The secondary outcome was compliance rate and adherence to FM wear among patients.

RANDOMIZATION

Randomizer software and the sealed envelope technique were used to randomly allocate patients 1:1 into either group I (tooth-borne FM/Alt-RAMEC) or group II (skeletally anchored FM/Alt-RAMEC).

BLINDING

It was not possible to blind to treatment allocation, but blinding was used when assessing the outcomes.

RESULTS

Numbers randomized and analysed. Thirty-five patients were allocated. Group I consisted of 18 subjects and group II consisted of 17 subjects. One patient in group I dropped out due to illness, so 17 subjects in each group completed the study.

OUTCOMES

Post-treatment changes in group I showed significant increases in SNA (2.10°), ANB (3.90°), Wits (4.70 mm), and overjet (5.40 mm). Group II showed significant increases in ANB (3.10°), Wits (3.20 mm), and overjet (4.50 mm). Wearing time for group I patients was 7.87 ± 2.88 hours/day and for group II was 6.98 ± 2.68 hours/day, with no significant difference between the groups.

LIMITATIONS

Lack of long-term follow-up post-treatment, making the conclusion applicable only in the short term.

HARMS

No harm was observed in both groups.

CONCLUSION

Despite the large difference between the measured and the patient-reported daily WT, both tooth-borne and skeletally anchored FM/Alt-RAMEC showed positive, similar, skeletal and dental effects.

CLINICAL TRIAL REGISTRATION

ISRCTN12197405.

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 : A retrospective study

PURPOSE

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.

METHODS

A total of 30 patients 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 (10 males and 5 females, 10.99 ± 1.80 years), expansion screws were activated for a week (two turns/day), then deactivated in the following week (two turns/day). The activation-deactivation protocol continued for 6 or 7 weeks. In the RME/FM group (10 males and 5 females, 11.61 ± 1.20 years), 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.

RESULTS

Both groups showed a significant 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).

CONCLUSION

The Alt-RAMEC protocol was found to be more effective in the correction of skeletal class III malocclusion in the short term.

Effects of Alt-RAMEC protocol with facemask therapy in cleft lip palate patients in a sample of Pakistani population

OBJECTIVE

The objective of the study is to evaluate the skeletal, dentoalveolar and soft tissue changes before and after treatment with Alt-RAMEC protocol and protraction headgear in comparison to the controls.

MATERIAL AND METHODS

A quasi experimental study was conducted in the orthodontic department on 60 patients of cleft lip and palate. These patients were divided into two groups. Group I was the Alt-RAMEC group that underwent Alt-RAMEC protocol followed by facemask therapy while group II was the control group that underwent RME and facemask therapy. Total treatment time in both the groups was approximately 6 to 7 months. Mean and standard deviation was calculated for all the quantitative variables. Pre and post treatment changes between treatment and control groups were made using paired t-test. Intergroup comparison between treatment and control group was analyzed using independent t-test. Significance for all tests was predetermined at a P-value of  ≤ 0.05.

RESULTS

The Alt-RAMEC group showed significant forward movement of maxilla and improvement in the maxillary base. A remarkable improvement in SNA was seen. The overall outcome was better maxillo-mandibular relationship as shown by positive ANB values and angle of convexity. More effect on maxilla and least effect on mandible was notified with Alt-RAMEC protocol and facemask therapy. Improvement in transverse relationship was also evident in the Alt-RAMEC group.

CONCLUSION

Alt-RAMEC protocol in combination with protraction headgear is a better alternative to treat cleft lip and palate patients in comparison to the conventional protocol.

A retrospective comparison of two protocols for correction of skeletal Class III malocclusion in prepubertal children: hybrid hyrax expander with mandibular miniplates and rapid maxillary expansion with face mask

BACKGROUND

This study compared the skeletal and dental effects of a hybrid maxillary expander with mandibular miniplates (HE-MP) and Class III elastics to conventional tooth-borne rapid maxillary expander and face mask (RME-FM) in skeletal Class III treatment.

METHODS

This retrospective study included 36 skeletal Class III patients. Eighteen patients (mean age 10.24 ± 1.31 years) were treated with a hybrid expander, two mandibular L-shaped miniplates and full-time Class III elastics (HE-MP group). Their results were compared to a group of patients treated with conventional RME-FM (n = 18; mean age 10.56 ± 1.41 year). Radiographs were taken before (T1) and after treatment (T2). All patients were in cervical maturation stages CS1-CS3 at T1. The measured outcomes were the changes in sagittal and vertical skeletal and dental cephalometric measurements.

RESULTS

Treatment time was approximately 15.5 ± 2.8 months with the HE-MP and 11.85 ± 3.41 months for the RME-FM. The Class III malocclusion was corrected in both groups with significant changes. The maxilla advanced more in the HE-MP group, with an increase in SNA of 4.26° ± 2.15° compared to 1.14 ± 0.93 in the RME-FM group (p < 0.001). The effect on the mandible was similar in both groups, while the overall skeletal change was significantly greater with HE-MP, with an increase in the ANB of 5.25° ± 2.03° and a Wits appraisal increase of 6.03 ± 3.13 mm, as opposed to 2.04° ± 1.07° and 2.94 ± 1.75 mm with the RME-FM (p < 0.001). Dental changes were significantly higher with RME-FM, with an increase in incisor inclination (U1-SN) of 5.02° ± 3.93° (p < 0.001), with no significant changes in the HE-MP group. The mandibular incisors retroclined by 5.29° ± 3.57° at L1-MP with the RME-FM, while they advanced slightly with the HE-MP by 2.87° ± 5.37° (p < 0.001).

CONCLUSION

The use of skeletal anchorage for maxillary expansion and protraction significantly increases skeletal effects and reduces dental side effects compared to tooth-borne maxillary expansion and protraction. These results need to be investigated in the long term.

Evaluation of rapid maxillary expansion or alternating rapid maxillary expansion and constriction on Eustachian tube function with audiological tests: A randomized clinical trial

OBJECTIVES

Maxillary expansion improves the hearing function. This trial aimed to examine the effects of Eustachian tube function (ETF) with audiological tests in orthodontic patients who underwent rapid maxillary expansion (RME) or alternate rapid maxillary expansion and constriction (Alt-RAMEC) treatment.

METHODS

Forty individuals (mean age = 13.35 years) included in the trial had a healthy eardrum, no history of orthodontic treatment, maxillary constriction, mandibular constriction and were not affected by acute or chronic otitis. Patients were randomly assigned to one of two groups (n = 20 each): the RME protocol or the Alt-RAMEC protocol. ETF was evaluated using Williams' test at three time points: before expansion (T0), after expansion (T1), and in the 3rd month of retention (T2).

RESULTS

In the RME group, Eustachian tube dysfunction (ETD) was observed in 18 of 40 ears before expansion (T0). The RME group showed significant improvement in tube function in the 3rd month of retention (T2) (p = 0.003). In the Alt-RAMEC group, ETD was observed in 22 of the 40 ears at baseline (T0). Significant improvements in tubal function were observed in the Alt-RAMEC group after expansion (T1) (p = 0.008) and in the 3rd month of retention (T2) (p < 0.001). In the RME group, 17 of 18 ears recovered, while in the Alt-RAMEC group, 21 of 22 ears recovered.

CONCLUSION

Eustachian tube function improved in the RME and Alt-RAMEC groups compared to the pre-expansion period.

REGISTRATION

This trial was not registered.

Long-term skeletal and dentoalveolar effects of hybrid rapid maxillary expansion and facemask treatment in growing skeletal Class III patients: a retrospective follow-up study

BACKGROUND

Regardless of the treatment protocol, stability in Class III patients always represents a major concern. The aim of this study was to assess the short and long-term skeletal and dentoalveolar modifications in a group of class III patients treated with hybrid rapid maxillary expander (RME) and facemask (FM). Indeed, no long-term studies have been conducted yet with the objective of evaluating the effects of this kind of approach when applied to patients who have already gone thought their peak of growth.

MATERIAL AND METHODS

27 patients with skeletal Class III malocclusion were treated using hybrid RME according to alternating rapid maxillary expansion and constriction (ALT-RAMEC) protocol, followed by 4 months of facemask therapy. After the orthopaedic phase, each patient underwent orthodontic treatment with fixed multibracket appliances. A mean follow-up of 7 years, 10 months was performed. Pre-treatment (TO), post-treatment (T1) and follow up (T2) cephalometric tracing were analysed, comparing dental and skeletal measurements.

RESULTS

Point A advanced by a mean of 3.5 mm with respect to VerT, then relapsed by 0.7 in the post-facemask period, thereby yielding of a mean advancement of 2.7 at T2. The sagittal relationship significantly changed after RME + facemask protraction (3.8° of ANB and 5.189 mm of Wits). Although both Wits and ANB values worsened over time, the improvement from T0 is still appreciable at T2.

CONCLUSION

Despite the physiological relapse due to mandibular growth, the long-term cephalometric follow-up confirms the maintenance of all positive outcomes of the previous orthopaedic treatment with hybrid RME and facemask.

Post-pubertal effects of the Alt-RAMEC/FM and RME/FM protocols for the early treatment of Class III malocclusion: a retrospective controlled study

OBJECTIVE

To assess the stability of the effects of the modified Alt-RAMEC and facial mask (FM) protocol at a post-pubertal observation.

METHODS

Twenty-one Class III patients (11 males and 10 females, 6.5 ± 0.7 years) treated consecutively with the Alt-RAMEC/FM approach and presenting with lateral cephalograms taken before treatment (T1), after treatment (T2), and at post-pubertal observations (T3) were compared with 22 Class III patients (9 males and 13 females, 6.9 ± 1.2 years) treated with the rapid maxillary expansion (RME) and FM protocol and with 15 Class III untreated subjects (7 males and 8 females, 6.2 ± 2.2 years). At T3, all patients showed a post-pubertal skeletal maturation stage (CS4-CS6). Descriptive statistics and statistical comparisons between the three groups at T1 and for the T3-T1, T2-T1, and T3-T2 changes were assessed by means of the ANOVA or Kruskal-Wallis test.

RESULTS

During the overall observation period, Alt-RAMEC/FM and RME/FM protocols produced statistically significant favourable effects when compared with the Control group (ANB + 2.8° and +2.2°, respectively; Wits appraisal +4.4 mm and +2.7 mm, respectively). No statistically significant differences were found between the outcomes of the Alt-RAMEC/FM and RME/FM protocols neither at the post-pubertal or short-term observations.

LIMITATIONS

Retrospective study and the comparison with an historical control sample of subjects with untreated Class III malocclusion.

CONCLUSIONS

The Alt-RAMEC/FM protocol cannot be recommended as the approach of choice for the therapy of Class III dentoskeletal disharmony in very young subjects compared to the conventional RME/FM protocol.

Effects of rapid maxillary expansion or alternating rapid maxillary expansion and constriction on nasal mucociliary clearance : A randomized clinical trial

PURPOSE

This parallel trial aimed to evaluate the changes in nasal mucociliary clearance (MCC) after a rapid maxillary expansion (RME) protocol or an alternating rapid maxillary expansion and constriction (Alt-RAMEC) protocol in orthodontic patients.

METHODS

This trial included 36 patients with a mean age of 14.38 years, with a narrow maxillary arch, bilateral posterior crossbite, no narrowing of the mandibular arch, no previous orthodontic treatment, and no nasal or systemic disease. Patients were randomly distributed into two groups (n = 18 each)-one group was treated with the RME protocol and the other group was treated with the Alt-RAMEC protocol. MCC was evaluated using the saccharine transit time (STT) test, which was measured for each individual before expansion (T0), after expansion (T1), and after a 4-month retention phase (T2). The study was single blinded, and blinding was applied only to the outcome assessor. The primary objective was to evaluate the effect of the Alt-RAMEC and RME protocols on MCC. The secondary objective was to determine the relationship between age, sex, and MCC. The χ ² test and independent samples t‑test were used to evaluate the data.

RESULTS

The STT decreased after expansion and retention in the RME group. In the Alt-RAMEC group, the STT decreased after expansion and slightly increased after retention. When the RME and Alt-RAMEC groups were compared, the STT showed a significant difference after expansion and retention (p < 0.05). No significant relationship was observed between age and sex and STT (p > 0.05).

CONCLUSION

This study demonstrated that the Alt-RAMEC protocol improved MCC and had a positive effect on nasal physiology by increasing the nasal volume more than that achieved by RME.

Long-term follow-up of late maxillary orthopedic advancement with the Liou-Alternate rapid maxillary expansion-constriction technique in patients with skeletal Class III malocclusion

INTRODUCTION

The objective of this study was to evaluate short and long-term results of the application of the alternate rapid maxillary expansion/constriction (Alt-RAMEC) technique in patients with skeletal Class III malocclusion.

METHODS

Forty-two white patients were consecutively treated with the Alt-RAMEC technique. The average age of the patients was 12.7 ± 1.6 years (range, 9.4-15.9 years) before protraction. The average age at long-term follow-up was 19.4 ± 2.8 years (range, 17.2-26.9 years). A sample of nontreated patients with Class III malocclusion from the archives of orthognatic surgery in our hospital was used as a control group. The initial records were matched for sex, the severity of Class III malocclusion, and age (mean, 12.1 ± 1.4 years; range, 9.7-14.1 years) with the old records available in the archive. The control sample had records presurgery (mean, 19.8 ± 2.2 years; range, 16.6-21.6 years).

RESULTS

The sagittal advancement of A-point, after the application of the technique, was 5.43 ± 2.71 mm. Some mandibular dentoalveolar adaptation was noted. The position of the maxilla was stable in the long term. In contrast, the control group showed limited growth at the maxillary level during the long-term follow-up period.

CONCLUSIONS

Our results showed that the Alt-RAMEC technique, performed at the correct time, with a double-hinged expander, followed by Class III spring or elastic traction, 24 h/d, allows for satisfactory maxillary protraction, with stable long-term results. The comparison with a sample of matched nontreated patients with Class III malocclusion allowed to suggest the positive effect of the treatment on the maxillary position vs the natural evolution of the Class III skeletal discrepancy.

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

Treatment of Class III malocclusion is a challenge for orthodontists. The best time to intercept this malocclusion is as early as in the deciduous dentition. Orthopedic management of Class III individuals with retruded maxilla is by protraction facemask along with rapid maxillary expansion (RME). It results in forward and downward maxillary growth and backward mandibular rotation. Alternate RME and contraction (Alt-RAMEC) produces faster and more efficient results than maxillary protraction alone. The present case report describes the clinical application of Alt-RAMEC protocol for the treatment of a Class III malocclusion.

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

OBJECTIVE

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSION

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.

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

INTRODUCTION

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.

METHODS

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 ± 1.37 years). Maxillary expansion with an activation rate of 0.5 mm/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 ± 1.60 years). In the Alt-RAMEC/FM group (7 males and 8 females; mean age, 10.01 ± 1.31 years), Alt-RAMEC was started simultaneously and throughout the entire course of maxillary protraction, with repetitive alternations between activation and deactivation of expanders (0.5 mm/d for 7 days). The patients in all groups were instructed to wear FMs for a minimum of 12 h/d. Pretreatment and posttreatment lateral cephalograms were all traced and measured.

RESULTS

The Alt-RAMEC group showed statistically more significant maxillary advancement than other groups (A-VRP, 3.87 mm vs 3.04 mm [RME/FM], vs 2.04 mm [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.

CONCLUSIONS

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.

Three-dimensional evaluation of treatment results of the Alt-RAMEC and facemask protocol in growing patients

PURPOSE

The aim of this retrospective study was to evaluate the skeletal, dental, and soft tissue effects of the alternating rapid maxillary expansions and constrictions (Alt-RAMEC) protocol combined with a facemask in prepubertal patients.

METHODS

The study group (mean age 9.74 ± 1.46 years) consisted of 20 patients with class III malocclusion characterized by maxillary retrognathism. They were treated with a facemask for 7 months following a 9‑week Alt-RAMEC protocol. Cone-beam computed tomography (CBCT) records and three-dimensional (3D) photographs taken before (T0) and after the protraction and retention period (T1) were evaluated. The study group was compared with a well-matched control group of 16 untreated patients (mean age 9.44 ± 0.79 years) with the same malocclusion. The records for the control group included cephalometric radiographs and 3D photographs.

RESULTS

In the study group, significant forward movements of A point (3.49 mm), nasal (2.91 mm) and zygomatic bones were achieved. Intermolar, internasal, and interzygomatic widths increased. Soft tissue points followed the hard tissue movements, apart from b and pog. In the control group, A (0.97 mm), B (1.69 mm), Pog, and b points presented forward movement. Significant differences were found regarding the forward movement of the maxilla between the groups.

CONCLUSION

The Alt-RAMEC/facemask protocol was effective not only in the maxillary region but also in the midface.

Long-term maxillary three dimensional changes following maxillary protraction with or without expansion: A systematic review and meta-analysis

Background/purpose

Maxillary protraction with or without expansion appears to be an effective orthopedic treatment in skeletal class III growing patients, but the long-term effect on maxilla changes is less clear. The aim of this meta-analysis was to evaluate long-term three dimensional skeletal effects on maxilla through face mask (FM) with or without rapid maxillary expansion (RME) in skeletal CIII growing patients.

Materials and methods

We searched database including PubMed, Science Direct, Embase and Web of Science through Feb 2020. Inclusion criteria were randomized controlled trials or cohort studies recruiting growing patients who received maxillary protraction and/or expansion and comparing the treatment groups with untreated controls. The follow-up periods were more than 3 years. Risk of bias was assessed using the Cochrane tools (RoB2.0 and ROBINS-I). GRADE was used to qualify the evidence.

Results

This meta-analysis included 6 studies comprising 327 participants in total. No statistically significant changes were observed on the degree of Sella-Nasion-A point (SNA) in the treated groups when compared with the untreated controls. However, significant increase on maxillary rotation degree (mean difference: 8.20, 95% CI = 6.87–9.53, p < 0.001) and maxillary base width (mean difference: 2.27, 95% CI = 1.39–3.15, p < 0.001) in the treated groups, if compared with untreated controls.

Conclusion

Our results indicated that FM and FM/RME treatments might not be long-term effective on correcting maxillary anteroposterior hypoplasia in growing patients. Additionally, more long-term studies are still necessary to further assess its skeletal benefits on maxilla in vertical and transverse dimension.

Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) May Be More Effective Than Rapid Maxillary Expansion Alone for Protraction Facial Mask Treatment

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

The effectiveness of Alt-RAMEC combined with maxillary protraction in the treatment of patients with a class III malocclusion: a systematic review and meta-analysis, Mohammed Almuzian, Elise McConnell, M. Ali Darendeliler, Fahad Alharbi & Hisham Mohammed. J Orthod 2018;45(4);250-9.

SOURCE OF FUNDING

No financial support was reported.

TYPE OF STUDY/DESIGN

Systematic review.

Comparison of treatment effects of different maxillary protraction methods in skeletal class III patients

OBJECTIVE

The aim of this study was to compare treatment outcomes with different maxillary protraction methods in patients with skeletal Class III malocclusion resulting from maxillary retrognathia.

SETTING AND SAMPLE POPULATION

A total of 55 individuals consisting of 29 females and 26 males with a mean age of 11.4 ± 1.06 years were included in this study.

MATERIAL AND METHODS

Fifty-five treated maxillary retrognathic patients who underwent different protraction facemask methods were evaluated. Eighteen patients treated with RME were in the first group, and 19 patients treated with a modified Alt-RAMEC protocol were in the second group; eighteen patients on whom face masks with miniplates were applied were included in the skeletal anchorage (SA) group. Thirty measurements were made on lateral cephalometric radiographs before and after treatment. Differences between the groups were assessed with the ANOVA test.

RESULTS

The mean age was higher in the SA group (11.96 ± 0.92 years) compared with the other groups. The mean ANB angle increased by 2.96°, 4.91° and 3.86° in the RME, Alt-RAMEC and SA groups, respectively. The forward movement of the maxilla was similar between the groups. However, while the rate of protraction was higher in the modified Alt-RAMEC group, a greater skeletal effect was found in the SA group.

CONCLUSION

The most effective method in terms of skeletal effect is the application of the face mask with skeletal anchorage; the modified Alt-RAMEC protocol can be applied before face mask to obtain faster protraction.

Maxillary protraction in patients with unilateral cleft lip and palate : Evaluation of soft and hard tissues using the Alt-RAMEC protocol

PURPOSE

The aim of this study was to evaluate the hard and soft tissue effects and differences of the Alt-RAMEC protocol to the facemask and conventional facemask protocols in patients with unilateral cleft lip and palate.

METHODS

This prospective study was carried out with 30 patients with unilateral cleft lip and palate with skeletal and dental class III malocclusions who were referred to a university department of orthodontics. The patients were evaluated with the cervical vertebral maturation method and divided into two groups, each consisting of 15 patients. The patients in group I (mean age 10.00 ± 0.73 years) were treated according to conventional facemask protocol, and the patients in group II (mean age 10.07 ± 2.43 years) were treated according to the Alt-RAMEC protocol before facemask application. Lateral cephalometric radiographs were evaluated by using the Dolphin Imaging Software version 11.7. The skeletal, dentoalveolar and soft tissue differences and treatment times were evaluated.

RESULTS

Group II demonstrated a 5.73° increase in SNA, which was statistically significant, while this increase was 3.13° in group I (p < 0.001). Results for Co‑A and A‑PTV showed a significant increase for group II only (group I: 1.02 mm, 1.06 mm, group II: 3.02 mm, 2.21 mm; p < 0.05 and p < 0.01, respectively). In addition, group II presented significant increase for the values of ANB, N‑A-Pg, SN/MP, Wits, U1-SN, U1-L1, U1-PTV, U1-FHP, U6-PTV, U6-FHP, overjet, Ss-PTV, UL-PTV and UL‑S line (p < 0.001). The treatment mean times were 7.3 months in group I and 4.7 months in group II (p < 0.01).

CONCLUSION

Applying the facemask after having followed the Alt-RAMEC protocol induced more skeletal, dentoalveolar and soft tissue changes in comparison to the conventional facemask protocol in patients with unilateral cleft lip and palate.

Comparison of the Changes Following Two Treatment Approaches: Rapid Maxillary Expansion Versus Alternate Rapid Maxillary Expansion and Constriction

Objective

The aim of the present study was to evaluate the hard and soft tissue changes following rapid maxillary expansion (RME) and alternate rapid maxillary expansion and constriction (Alt-RAMEC) therapies.

Methods

A total of 54 patients who needed maxillary expansion or Alt-RAMEC procedure were recruited and divided into two groups (27 subjects in the RME group and 27 subjects in the Alt-RAMEC group). Expansion screw was activated 0.5 mm/day (2 turns/day) in the RME group. Approximately 11 mm of expansion was achieved. In the Alt-RAMEC group, the screw was activated 1 mm/day (4 turns/day) during a period of 4 weeks. In the first and third weeks, the screw was opened; in the second and fourth weeks, the screw was closed. Cephalometric tracing and analyzing were done with the aid of digital software. Lateral cephalometric radiographs were obtained before (T0) and after (T1) RME and Alt-RAMEC applications.

Results

In the RME group, the maxilla moved forward and downward. Upper incisor retrusion was observed according to the reference planes. In addition, the tip of the nose moved forward, and the upper lip moved downward. In the Alt-RAMEC group, the nasolabial angle became more obtuse, and the stomion superius moved backward and downward.

Conclusion

RME therapy resulted in skeletal and dental changes in the maxilla and related structures, favoring a contribution to solving Class III problems. No remarkable changes were recorded in the Alt-RAMEC group.

3D effects of a bone-anchored intra-oral protraction in treating class III growing patient: a pilot study

OBJECTIVES

The aim of this prospective case series study is to assess the three-dimensional (3D) skeletal and soft tissue effects of the alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol in conjunction with a miniscrew-supported class III elastic wear in class III growing patients.

MATERIALS AND METHODS

Fourteen consecutive participants (mean age 12.05 ± 1.09 years), who displayed class III malocclusions with retrognathic maxillae, were recruited. A cone beam computed tomography (CBCT) scan was acquired before commencing treatment (T1). All participants were treated with a tooth-bone-borne rapid maxillary expansion (hybrid MARME) appliance that was activated by the Alt-RAMEC protocol for 9 weeks. This was followed by full-time class III elastics, delivering 400 g/side, to protract the maxilla. When a positive overjet was achieved, protraction was ceased and a post-treatment CBCT scan (T2) was taken. The 3D analysis of pre- and post-treatment CBCT scans was blinded. The scans were registered on the anterior cranial base. The Euclidean distance between the two extracted surface models of the pre- and post-treatment scans was displayed as a color surface map.

RESULTS

All participants completed the intervention successfully. The majority of the participants showed protraction of the anterior maxillary region (71.4%) and in the zygomatic processes (64.2%). The maxilla significantly protracted (SNA 1.87° ± 1.06°; Vert.T-A 3.29 ± 1.54 mm), while the mandibular base significantly redirected posteriorly (SNB - 2.03° ± 0.85°, Vert.T-B - 3.43 ± 4.47 mm) and that was reflected on the ANB and Wits measurements. No adverse effects were observed.

CONCLUSION

Class III elastics combined with the Alt-RAMEC activation protocol of the hybrid MARME appliance is an effective treatment method for mild/moderate class III malocclusions. A long-term follow-up and comparisons with other treatment modalities are required.

A Bayesian network meta-analysis of orthopaedic treatment in Class III malocclusion: Maxillary protraction with skeletal anchorage or a rapid maxillary expander

To evaluate and compare the effectiveness of orthopaedic treatment for Class III malocclusions using skeletal anchorage or a rapid maxillary expander for maxillary protraction. Electronic databases, including PubMed, EMBASE, Cochrane Library and Web of Science, were searched for randomized controlled trials (RCTs) and non-randomized clinical trials (CCTs) for orthopaedic treatment of Class III malocclusions. Five interventions were studied: a facemask with a maxillary temporary anchorage device (MTAD), a bone-anchored rapid maxillary expansion (BARME), a rapid maxillary expansion (RME), an alternate rapid maxillary expansion and contraction (Alt-RAMEC), and a bone-anchored intermaxillary traction (BAIMT). Eight outcomes (SNA, SNB, ANB, overjet, SN-GoGn, ANS-Me, IMPA (L1-MP), and U1-PP) were statistically polled. We conducted network meta-analysis using R statistical software with the GeMTC package. Twenty-five studies met the inclusion criteria. Compared with the RME group, the Alt-RAMEC group (mean difference (MD): 1.3; 95% credibility interval (CrI): 0.26, 2.3) and MTAD group (MD: 0.85; 95% CrI: 0.065, 1.6) showed a better effect on ANB in CCTs. Regarding the vertical relationship, the BAIMT group (MD: -2.2; 95% CrI: -5.2, 0.73) showed a smaller effect regarding increasing the vertical dimension of ANS-Me. The RME, MTAD and Alt-RAMEC group showed a higher ability to decrease the angle of L1-MP. The Alt-RAMEC and MTAD protocol have a higher possibility to obtain a skeletal and tooth effect in sagittal relationships. The BAIMT protocol can acquire a better skeletal effect in sagittal relationships with less vertical and dental changes. More well-designed RCTs are needed to ensure that the conclusion is reliable.

Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) protocol: A Comprehensive Literature Review

The aim of this comprehensive review is to introduce clinicians to the increasingly popularity Alt-RAMEC procedure, a method commonly used in the treatment of class III malocclusion in the last 15 years. Another application of the literature to enhance the skeletal effects of Class III treatment on the maxillae is the Alternative Rapid Maxillary Expansion and Constriction (Alt-RAMEC) procedure introduced by Liou, which improves the effectiveness of the maxillae relative to the surrounding sutures and the enhancement of the maxillae. In the Alt-RAMEC protocol, maxillae will be enlarged to be 1 mm per day, first enlarged to 7 mm, and then the 1 mm screw is closed. In other weeks, in this order the screw of the expansion device is turned on for one week and then closed for one week, completing the Alt-RAMEC protocol at the end of the 9-week process. In this review, we will discuss the advantages and disadvantages of the studies, which include successful treatments by applying this protocol, differences with other methods, its effect on the airway, and its advantages and disadvantages.

The immediate effect of alternate rapid maxillary expansions and constrictions on the alveolus: a retrospective cone beam computed tomography study

Background

Rapid maxillary expansion reduced the expander’s anchor teeth buccal alveolar bone thickness. However, the effects of alternate rapid maxillary expansions and constrictions (Alt-RAMEC) on the expander’s anchor teeth alveolar thickness has not been assessed. The purpose of this retrospective study was to evaluate the effects of Alt-RAMEC on the alveolus surrounding the anchor teeth of a double-hinged expander.

Methods

Twenty-six individuals, including 12 males (11.5 ± 1.00 years) and 14 females (11.5 ± 0.90 years), who had double-hinged expander for 7 weeks of Alt-RAMEC and then 3 months of maxillary protraction, were included. Their cone beam computed tomography (CBCT) images taken 3–6 months before treatment (T0) and after 7 week of Alt-RAMEC (T1), were studied for the buccal alveolar bone thickness (BABT) and palatal alveolar bone thickness (PABT) of the expander’s anchor teeth (first molars and first and second premolars) in four axial sections. The intra-class correlation coefficient, Dahlberg’s formula, and paired t tests were used to analyze the method errors, and the intra-group changes of the BABT and PABT at T0-T1 were analyzed by paired t test (p < 0.05).

Results

The 7 weeks of Alt-RAMEC significantly reduced the BABT of the expander’s anterior anchor teeth (0.54~ 70 mm, p < 0.05) and at the cervical region (0.14~ 0.25 mm, p < 0.05), but not at the apical region of the expander’s posterior anchor teeth. The reduction of BABT by 7 weeks of Alt-RAMEC was within the scope of the initial BABT. On the opposite, the Alt-RAMEC significantly (p < 0.05) increased the PABT in the anterior anchor teeth and the cervical region of posterior anchor teeth.

Conclusions

A 7-week protocol of Alt-RAMEC with double-hinged expander for maxillary protraction might reduce the buccal alveolar bone thickness of the expander’s anchor teeth, although the reduction is within the scope of initial alveolar thickness of the expander’s anchor teeth.

Bone-anchored maxillary protraction in patients with unilateral complete cleft lip and palate and Class III malocclusion

OBJECTIVE

This prospective controlled study evaluated the effect of bone-anchored maxillary protraction therapy in cleft children with Class III malocclusion using CBCT-derived 3D surface models.

MATERIALS AND SUBJECTS

Eighteen cleft patients between 10 and 12 years old were included. Intermaxillary elastics were worn after the placement of four zygoma bone plates for 18 months. Uniquely, three age-matched untreated groups including both cleft subjects and non-cleft subjects with Class III malocclusion served as controls. Profile photos and CBCT scans for each patient were taken before (T0) and 18 months after the protraction (T1). 3D measurements were made on CBCT surface models from the treatment group using tomographic color mapping method. Cephalometric measurements were made on lateral cephalogram reconstructed from the CBCT scans and were compared with those obtained from the control groups.

RESULTS

Two thirds of the treatment subjects showed improved lip projection towards more convex facial profile. The most significant skeletal changes on 3D surface models were observed at the zygomatic regions (mean 1.5-mm forward, downward, and outward displacement) and at the maxillary complex (mean 1.5-mm forward displacement). Compared with the control groups, the treatment subjects showed significant increase in the SNA and ANB angles, increased Wits appraisal, a more forward movement of point A and overjet improvement (p < 0.05).

CONCLUSIONS

BAMP in cleft patients gives a significant forward displacement of the zygomaxillairy complex in favor of the Class III treatment.

CLINICAL RELEVANCE

This treatment method shows clearly favorable outcome in cleft patients after 1.5 years of BAMP.

A Retrospective Evaluation of Conventional Rapid Maxillary Expansion versus Alternate Rapid Maxillary Expansion and Constriction Protocol Combined with Protraction Headgear in the Management of Developing Skeletal Class III Malocclusion

Aims and Objectives:

The reverse pull headgear has been widely used to intercept a developing skeletal Class III malocclusion with maxillary deficiency. Rapid maxillary expansion (RME) is recommended along with the reverse pull headgear because there is disruption of the circummaxillary and intermaxillary sutures. This, in turn, expedites the orthopedic effect of the reverse pull headgear. However, studies have shown that the circummaxillary sutures may not be fully disrupted by the use of RME alone. The protocol of alternate RME and constriction (Alt-RAMEC) has been found to produce much more beneficial effects. Hence, this retrospective study was conducted to compare and assess the results obtained in the two methods.

Materials and Methods:

This study comprised pre- and post-treatment lateral cephalograms of two groups of nine patients each (total 18 patients – 10 females and 8 males) having skeletal Class III malocclusion (ANB<0°) due to a retrognathic maxilla with or without associated mandibular prognathism treated at the Department of Orthodontics of a teaching institute in Kerala. The patients were treated with either Alt-RAMEC/protraction or RME/protraction. The statistical analysis of the data was done using statistical package SPSS Version 16 software (SPSS Inc., Chicago, IL, USA).

Results:

Skeletal, dental, and soft-tissue parameters in Group 2 (Alt-RAMEC group) showed very significant changes with the maxilla moving forward, mandible rotating backward and downward, and proclination of the maxillary incisors when compared to Group 1.

Conclusions:

It may be concluded from the results of our study that the Alt-RAMEC protocol and reverse pull headgear might be more effective than conventional RME and the reverse pull headgear to correct a retruded maxilla in a developing skeletal Class III patient.

Short- and Long-Term Effects of Late Maxillary Advancement With the Liou-Alt-RAMEC Protocol in Unilateral Cleft Lip and Palate

Objective:

The objective of this retrospective longitudinal study was to evaluate short- and long-term results of the application of the Liou Alt-RAMEC (alternate rapid maxillary expansion and constriction) technique, a late orthopedic maxillary protraction technique, with intraoral anchorage, in patients with cleft.

Materials and Methods:

Twenty-six patients with unilateral cleft lip and palate (UCLP) were consecutively treated with the Alt-RAMEC technique. The average age of the patients was 11.7 years (10.3-13.2 years) before protraction and 18.3 years (17.4-21.1 years) at long-term follow-up. A sample of nontreated patients with UCLP was used as a control group. It was matched for sex, skeletal class III, and age (11.3 years). The control sample had records at the end of growth (18.7 years).

Results:

The sagittal advancement of A-point, after the application of the technique, was 5.7 (2.17) mm. Some mandibular dentoalveolar and positional adaptation was noted. The position of the maxilla was stable in the long term. On the other hand, the UCLP control group showed hardly any growth at the maxillary level during the long-term follow-up period.

Conclusion:

Our results showed that the Alt-RAMEC technique, performed at the correct time, with a double-hinged expander, followed by class III spring or elastic traction, 24 hours per day, allows for satisfactory maxillary protraction, with, at this stage, apparently stable long-term results. Nevertheless, as only 50% of the patients had long-term follow-up data, we are still unable to predict the percentage of patients which will not eventually need orthognathic surgery.

Is alternate rapid maxillary expansion and constriction an effective protocol in the treatment of Class III malocclusion? A systematic review

Introduction:

the treatment of Class III malocclusion in early age is one of the greatest challenges for orthodontists, and the establishment of more effective treatment method is a constant concern for these professionals. Thus, the objective of this systematic review is to verify the effectiveness of the therapy protocol for alternate rapid maxillary expansion and constriction (Alt-RAMEC) in the early treatment of Class III malocclusion.

Methods:

searches were performed in the following electronic databases: Cochrane Library, Medline (EBSCO and PubMed), SciELO, LILACS and Scopus. The following inclusion criteria were used: in vivo studies conducted with early intervention (patient in craniofacial development phase) with the use of the Alt-RAMEC protocol. Reviews, case reports, editorials, and studies with syndromic patients or under use of systemic drug were excluded. Duplicates were also excluded. The studies were assessed for methodological quality using the Cochrane tool for assessment of risk of bias, and classified as high or low risk of bias.

Results:

53 articles were found. Duplicates exclusion was thus performed and 35 articles remained. After inclusion analysis, only 5 matched the criteria. Two articles were classified as low risk of bias and three as high risk of bias. It was observed that the Alt-RAMEC enable protraction in less time and with better results, promoting greater effectiveness in the protraction treatment of Class III malocclusion.

Conclusions:

Although there is positive evidence of the effectiveness of early treatment with the Alt-RAMEC protocol in patients with Class III malocclusion, further studies are needed to confirm its effectiveness using long-term methodology.

Changes in pharyngeal airway dimensions and hyoid bone position after maxillary protraction with different alternate rapid maxillary expansion and construction protocols: A prospective clinical study

OBJECTIVE

To evaluate the changes in pharyngeal airway dimensions and the position of the hyoid bone after maxillary protraction with different alternate rapid maxillary expansion and construction (Alt-RAMEC) protocols in patients with skeletal class III malocclusion as a result of maxillary retrusion.

MATERIAL AND METHODS

The patients with skeletal class III malocclusions were consecutively divided into two groups. Group 1 consisted of 17 patients (11 boys and 6 girls, mean age 11.31 ± 1.71 years) who had the Alt-RAMEC protocol for 5 weeks, and group 2 consisted of 17 patients (10 boys and 7 girls, mean age 11.64 ± 1.24 years) who had the Alt-RAMEC procedure for 9 weeks. In this study, 4 angular and 13 linear measurements were performed to evaluate the skeletal and pharyngeal airway changes that occurred after maxillary protraction.

RESULTS

A significant increase in the maxillary growth, inhabitation of mandibular growth, and clockwise rotation of the mandible caused the improvement of the maxillo-mandibular relationship in both groups. Those changes caused a significant increase in the upper pharyngeal airway dimension (P < .01) and affected the vertical position of the hyoid bone in both groups (P < .05 and P < .01, respectively). However, changes that occurred in both groups were found to be similar for all airway variables (P > .05).

CONCLUSION

Upper pharyngeal dimension and vertical position of the hyoid bone were affected by the maxillary protraction with different Alt-RAMEC protocols. There were no statistically significant differences between the groups.

Effects of hybrid-Hyrax, Alt-RAMEC and miniscrew reinforced heavy Class III elastics in growing maxillary retrusive patients. A four-year follow-up pilot study

Introduction

The aim of this study was to evaluate the short- and long-term effects of hybrid-Hyrax, Alt-RAMEC and applied, miniscrew reinforced, heavy intermaxillary elastics on a modified lingual arch in growing skeletal Class III patients.

Methods

Fifteen subjects (seven male, eight female) were included, with an average age of 12.52 ± 0.94 years, of cervical vertebrae maturation (CVM) stage CS2-CS4 and skeletal Class III malocclusions due to a retrognathic maxilla. Nine weeks of Alt-RAMEC were followed by eight to nine weeks of maxillary protraction with heavy 400 gm Class III elastics worn 24 h/day. Treatment was finalised with orthodontic fixed appliances. Cone beam computed tomographic (CBCT) scans were taken initially (T1), at the end of maxillary protraction (T2) and four years after active orthopaedic treatment (T3). Cephalometric measurements were performed on reconstructed lateral cephalograms and the differences between time intervals were calculated using an analysis of variance (ANOVA).

Results

A positive overjet was achieved in all but one subject. From T1 to T2, A point advanced 3.12 ± 3.42 mm and from T2 to T3 advanced a further 2.21 ± 3.49 mm. Significant initial increases in SNA of 1.05° ± 1.10° (p = 0.004), ANB of 2.71° ± 1.01° (p = 0.00), Wits of 4.49 ± 2.21 mm (p = 0.00) and overjet of 4.90 ± 1.66 mm (p = 0.00) were accomplished and maintained without significant changes in the vertical dimension. Upper and lower incisor inclinations were not affected by the protraction protocol but significantly increased (U1-PP: 8.39° ± 5.59°) between T2 and T3. SNB decreased initially by 1.67° ± 1.34° (p = 0.00) but relapsed due to residual mandibular growth and a counterclockwise rotation of the mandibular plane.

Conclusion

The hybrid-Hyrax Alt-RAMEC combined with miniscrew reinforced heavy Class III elastics resulted in a favourable and stable Class III correction.

Effect of maxillary protraction with alternating rapid palatal expansion and constriction vs expansion alone in maxillary retrusive patients: a single-center, randomized controlled trial

INTRODUCTION

The objective of this randomized controlled trial was to investigate the effects of facemask protraction combined with alternating rapid palatal expansion and constriction (RPE/C) vs rapid palatal expansion (RPE) alone in the early treatment of maxillary retrusive patients.

METHODS

Patients with a midface deficiency were recruited and randomly allocated into either the control group (RPE) or the intervention group (RPE/C). Eligibility criteria included the following: age 7 to 13 years old, Class III malocclusion, anterior crossbite, ANB less than 0°, Wits appraisal less than -2 mm, A-Np less than 0 mm, and no cleft of lip or palate. The primary outcome was the degree of maxillary forward movement after treatment. The secondary outcomes were the changes of the other cephalometric variables after treatment and the treatment time. Simple randomization was carried out using a random number table at the beginning of the study. Envelopes containing the grouping information were used to ensure allocation concealment from the researchers. Blinding was applicable for cephalometric analysis only. Hyrax palatal expanders and facemask maxillary protraction were used in all patients. Patients in the RPE group were treated with rapid palatal expansion for 1 week. Patients in the RPE/C group were treated with RPE/C for 7 weeks. The expansion or constriction rate was 1 mm per day. Cephalometric analysis with traditional cephalometric measurements and an x-y coordinate system were used to compare the pretreatment and posttreatment cephalometric radiographs. Independent t tests were used to compare the data between the 2 groups.

RESULTS

A total of 44 patients were randomized to either the RPE group or the RPE/C group in a 1:1 ratio. One subject in the RPE group was lost to follow-up during the treatment. Per-protocol analysis was used. All the other 43 patients reached the treatment completion criteria and were analyzed (RPE group: n = 21; RPE/C group: n = 22). The average protraction time was 10.84 months in the RPE group, which was significantly longer than that in the RPE/C group (9.06 months) (effect size [ES], 1.78 [95% CI, 0.15, 3.42; P = 0.033]). Maxillary forward movement increased by 3.04 mm in the RPE/C group, which was significantly greater than that in the RPE group (2.11 mm) (ES, -0.93 [95% CI, -1.65, -0.20; P = 0.013]). The counterclockwise rotation of the palatal plane was 1.73° in the RPE/C group, which was significantly greater than that in the RPE group (0.83°) (ES, 0.90 [95% CI, 0.08, 1.73; P = 0.033]). The degree of mandibular downward and backward rotation was significantly smaller in the RPE/C group (P <0.05). No serious harm was observed during treatment and research.

CONCLUSIONS

Facemask maxillary protraction with RPE/C might positively affect the forward movement of the maxilla compared with facemask protraction with RPE alone in the early treatment of maxillary retrusive patients. Although the differences between the groups were statistically significant for forward movement of the maxilla and rotation of the palatal and mandibular planes, these may not be clinically relevant, since the differences were less than 1 mm and 1°, respectively.

REGISTRATION

This trial was not registered.

PROTOCOL

The protocol was not published before trial commencement.

FUNDING

This research was supported by Peking University Research Fund. No conflict of interest is declared.

Comparative characterization of maxillary expansion and alternate maxillary expansions and constrictions in rats

The purpose of this study was to evaluate whether the cranial and circumaxillary sutures react differently to maxillary expansion (ME) and alternate maxillary expansions and constrictions (Alt-MEC) in a rat model. Twenty-two male Sprague-Dawley rats (6 weeks old) were used and divided into three groups. In ME group (n=9), an expander was activated for 5 days. In Alt-MEC group (9 animals), an alternate expansion and constriction protocol (5-day expansion and 5-day constriction for one cycle) was conducted for 2.5 cycles (25 days total). The control group comprised 4 animals with no appliances used, each of two sacrificed on day 5 and day 25 respectively. Midpalatal suture expansion or constriction levels were assessed qualitatively and quantitatively by bite-wing X-rays and cast models. Distances between two central incisors and two maxillary first molars were measured on cast models after each activation. Circumaxillary sutures (midpalatal, maxillopalatine, premaxillary, zygomaticotemporal and frontonasal suture) in each group were characterized histologically. Results showed that midpalatal suture was widened and restored after each expansion and constriction. At the end of activation, the widths between both central incisors and first molars in Alt-MEC group were significantly larger than those in ME group (P<0.05). Histologically, all five circumaxillary sutures studied were widened in multiple zones in Alt-MEC group. However, only midpalatal suture was expanded with cellular fibrous tissue filling in ME group. Significant osteoclast hyperplasia was observed in all circumaxillary sutures after alternate expansions and constrictions, but osteoclast count increase was only observed in midpalatal suture in ME group. These results suggested that cranial and circumaxillary sutures were actively reconstructed after Alt-MEC, while only midpalatal suture had active reaction after ME.

Comparison of the effects of face mask treatment started simultaneously and after the completion of the alternate rapid maxillary expansion and constriction procedure

OBJECTIVE

To test the null hypothesis that there were significant differences for skeletal, dentoalveolar, and soft tissue changes induced by face mask (FM) started simultaneously and after an alternate rapid maxillary expansion and constriction (Alt-RAMEC) procedure.

MATERIALS AND METHODS

Thirty-six patients with Class III malocclusion due to maxillary deficiency were randomly assigned to Group I (FM started after the completion of the Alt-RAMEC) and Group II (FM started simultaneously with the Alt-RAMEC). The screw of the RME appliance was alternately activated and deactivated twice daily (0.20 mm per turn) for 1 week over the course of 8 weeks. The changes observed in both groups were assessed using the cephalometric lateral films and statistically evaluated using the paired t-test and Student's t-test.

RESULTS

Thirty patients completed the present prospective study. No significant differences were observed between the groups. Class III malocclusion and negative overjet were improved by means of skeletal changes in conjunction with upper incisor proclination in both groups. Skeletal contribution to overjet correction in Groups I and II was 91.70% and 86.10%, respectively. Maxilla showed a forward movement of 3.84 mm and 3.02 mm in Groups I and II, respectively.

CONCLUSIONS

The null hypothesis was rejected. Both groups showed similar results, and, thus, waiting until completion of the Alt-RAMEC procedure for the FM treatment is not necessary.

Short-term effects of a modified Alt-RAMEC protocol for early treatment of Class III malocclusion: a controlled study

OBJECTIVES

To assess the effects of a modified alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol in combination with facemask (FM) in Class III growing patients.

SETTING AND SAMPLE POPULATION

Thirty one Class III patients (17 males, 14 females) were treated with a modified Alt-RAMEC/FM protocol at the Department of Orthodontics of the University of Florence.

MATERIAL AND METHODS

All patients were evaluated at the beginning (T1, mean age 6.4 ± 0.8 years) and at the end of orthopedic therapy (T2, mean age 8.1 ± 0.9 years), and they were compared to a matched sample of 31 Class III patients (16 males and 15 females) treated with rapid maxillary expansion and facemask (RME/FM) and to a matched control group of 21 subjects (9 males and 12 females) with untreated Class III malocclusion. The three groups were compared with anova with Benjamini-Hochberg correction for multiple tests.

RESULTS

Both the Alt-RAMEC/FM and the RME/FM protocols showed significantly favorable effects leading to correction of the Class III malocclusion. The Alt-RAMEC/FM protocol produced a more effective advancement of the maxilla (SNA +1.2°) and greater intermaxillary changes (ANB +1.7°) vs. the RME/FM protocol. No significant differences were recorded as for mandibular skeletal changes and vertical skeletal relationships.

CONCLUSION

The Alt-RAMEC/FM protocol induced more favorable skeletal short-term effects compared with RME/FM therapy in Class III growing patients.

Skeletal, soft tissue, and airway changes following the alternate maxillary expansions and constrictions protocol

OBJECTIVE

To evaluate the skeletal, soft tissue, and airway effects of the alternate maxillary expansions and constrictions (Alt-RAMEC) protocol in prepubertal patients.

MATERIALS AND METHODS

The appliance containing a double-hinged expansion screw was applied to 20 patients with Class III skeletal malocclusion characterized by maxillary retrognathia. The mean age of the study group was 9 years and 8 months. The patients' parents were instructed to open the screw by 1 mm per day during the first week and to close it by 1 mm per day the week after. This alternate opening and closing was repeated for 9 consecutive weeks. Cone beam computed tomography records and three-dimensional photographs were taken before treatment and after 9 week of the Alt-RAMEC protocol.

RESULTS

Point A moved slightly forward (0.89 mm) and downward (0.92 mm) (P < .05). The average amount of expansion achieved at the level of point A was 5.54 mm (P < .05). Besides the maxilla, the expansive forces also affected the nasal bone, the zygomaticomaxillary and zygomaticotemporal sutures (P < .05). The soft tissue nasal width increased significantly. The airway volume of the anterior nasal compartment and the nasal cavity also increased (P < .05).

CONCLUSIONS

Slight forward movement of point A occurred with the Alt-RAMEC protocol. The expansion affected not only the maxilla but also other structures of the face. Significant cutaneous changes occurred in the paranasal area. Some significant increase in the upper airway volume was obtained.

Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children

BACKGROUND

Prominent lower front teeth (termed reverse bite; under bite; Class III malocclusion) may be due to a combination of the jaw or tooth positions or both. The upper jaw (maxilla) can be too far back or the lower jaw (mandible) too far forward, or both. Prominent lower front teeth can also occur if the upper front teeth (incisors) are tipped back or the lower front teeth are tipped forwards, or both. Various treatment approaches have been described to correct prominent lower front teeth in children and adolescents.

OBJECTIVES

To assess the effects of orthodontic treatment for prominent lower front teeth in children and adolescents.

SEARCH METHODS

We searched the following databases: Cochrane Oral Health Group's Trials Register (to 7 January 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 12), MEDLINE via OVID (1946 to 7 January 2013), and EMBASE via OVID (1980 to 7 January 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting children or adolescents or both (aged 16 years or less) receiving any type of orthodontic treatment to correct prominent lower front teeth (Class III malocclusion). Orthodontic treatments were compared with control groups who received either no treatment, delayed treatment or a different active intervention.

DATA COLLECTION AND ANALYSIS

Screening of references, identification of included and excluded studies, data extraction and assessment of the risk of bias of the included studies was performed independently and in duplicate by two review authors. The mean differences with 95% confidence intervals were calculated for continuous data. Meta-analysis was only undertaken when studies of similar comparisons reported comparable outcome measures. A fixed-effect model was used. The I2 statistic was used as a measure of statistical heterogeneity.

MAIN RESULTS

Seven RCTs with a total of 339 participants were included in this review. One study was assessed as at low risk of bias, three studies were at high risk of bias, and in the remaining three studies risk of bias was unclear. Four studies reported on the use of a facemask, two on the chin cup, one on the tandem traction bow appliance, and one on mandibular headgear. One study reported on both the chin cup and mandibular headgear appliances.One study (n = 73, low quality evidence), comparing a facemask to no treatment, reported a mean difference (MD) in overjet of 4.10 mm (95% confidence interval (CI) 3.04 to 5.16; P value < 0.0001) favouring the facemask treatment. Two studies comparing facemasks to untreated control did not report the outcome of overjet. Three studies (n = 155, low quality evidence) reported ANB (an angular measurement relating the positions of the top and bottom jaws) differences immediately after treatment with a facemask when compared to an untreated control. The pooled data showed a statistically significant MD in ANB in favour of the facemask of 3.93 ° (95% CI 3.46 to 4.39; P value < 0.0001). There was significant heterogeneity between these studies (I2 = 82%). This is likely to have been caused by the different populations studied and the different ages at the time of treatment.One study (n = 73, low quality evidence) reported outcomes of the use of the facemask compared to an untreated control at three years follow-up. This study showed that improvements in overjet and ANB were still present three years post-treatment. In this study, adverse effects were reported but due to the low prevalence of temporomandibular (TMJ) signs and symptoms no analysis was undertaken.Two studies (n = 90, low quality evidence) compared the chin cup with an untreated control. Both studies found a statistically significant improvement in ANB, and one study also found an improvement in the Wits appraisal. Data from these two studies were not suitable for pooling.A single study of the tandem traction bow appliance compared to untreated control (n = 30, very low quality evidence) showed a statistically significant difference in both overjet and ANB favouring the intervention group.The remaining two studies did not report the primary outcome of this review.

AUTHORS' CONCLUSIONS

There is some evidence that the use of a facemask to correct prominent lower front teeth in children is effective when compared to no treatment on a short-term basis. However, in view of the general poor quality of the included studies, these results should be viewed with caution. Further randomised controlled trials with long follow-up are required.

[Early treatment for class III malocclusions: the facts]

The goal of this article is to present some evidence based facts in order to answer the following questions: 1) Is early treatment of class III malocclusions effective? 2) Which therapeutic device is the most effective? 3) Are the results lasting? The positions of Jean Delaire and the author regarding the usefulness of routine early treatment for these dysmorphia will be discussed in a second article [4].