Skeletal and dentoalveolar effects of hybrid rapid palatal expansion and facemask treatment in growing skeletal Class III patients

Face Mask Therapy and Comprehensive Orthodontic Treatment for Skeletal Class III Malocclusion: A Case Report

Aim

This article aims to report a case of face mask therapy and comprehensive orthodontic treatment for skeletal class III malocclusion in a 16-year-old girl.

Background

Treating skeletal class III malocclusion in a growing patient is crucial, as it can help avoid the need for additional surgery. Early treatment also lessens the negative impacts of the patient's facial abnormality on their social life because surgery is only done later.

Case description

In this case report, a 14-year-old female patient presented with skeletal class III malocclusion with primary complaints of anterior crossbite. There was no relevant medical history. Face mask therapy and fixed appliance therapy were components of the treatment approach that successfully corrected the malocclusion. The total period of treatment was 20 months.

Conclusion

The treatment resulted in a harmonious face, a well-aligned smile arch, stable dental and skeletal relationships, and significant esthetic improvements, including improved facial symmetry and profile.

Significance

A growing teen who has a skeletal class III malocclusion and a maxillary deficit may be helped by a combination of face mask therapy and thorough orthodontic treatment. This case report outlines the use of the aforementioned technique to successfully treat a 14-year-old child with class III malocclusion and maxillary deficiencies.Early management of skeletal class III malocclusion in developing adolescents is vital as it can potentially eliminate the necessity for future surgical intervention, leading to improved treatment outcomes.Careful case selection, patient cooperation, and long-term stability enable a successful, stable, and esthetically pleasing treatment outcome.

How to cite this article

Le LN, Do TT, P Le KV. Face Mask Therapy and Comprehensive Orthodontic Treatment for Skeletal Class III Malocclusion: A Case Report. Int J Clin Pediatr Dent 2024;17(3):368-376.

Maxillofacial growth changes after maxillary protraction therapy in children with class III malocclusion: a dual control group retrospective study

PURPOSE

To investigate the balance between post-treatment effect and continued nature growth after maxillary protraction treatment in patients with skeletal class III malocclusion.

METHODS

31 patients aged 8.79 ± 1.65 years with skeletal Class III malocclusion had been treated with maxillary protraction and the treatment lasted an average of 1.16 years. The average observation duration after treatment in the maxillary protraction group was 2.05 ± 0.39 years. In the control groups, a sample of 22 patients (9.64 ± 2.53 years) with untreated skeletal class III malocclusion and 24 patients (9.28 ± 0.96 years) with skeletal class I malocclusion were matched to the treatment group according to age, sex and observation period. The mean observation interval of the control groups was 2.39 ± 1.29 years in the class III group and 1.97 ± 0.49 years in the class I group.

RESULTS

The active orthopedic treatment effect showed a opposite trend to the natural craniomaxillofacial growth effect after treatment in many aspects. In the observation duration of treatment group, decrease in ANB, Wits appraisal and BAr-AAr were statistically significant compared to class I control group (p < 0.001), and there was a significant increase in NA-FH (P < 0.001) which was contrary to class III control group. Treatment group presented a significant increase in Gn-Co (P < 0.01) and Co-Go (P < 0.001), except for changes in the extent of the mandibular base (Pog-Go, P = 0.149) compared to class I control group. The vertical maxillomandibular skeletal variables (Gonial; MP-SN; MP-FH; Y-axis) in treatment group decreased significantly compared to those in class III control group (P < 0.01). U1-SN and L1-MP showed a significant increase, which was similar to the class I group (P > 0.05), and overjet decreased significantly relative to both of the two control groups (P < 0.05).

CONCLUSION

Maxillary protraction therapy led to stable outcomes in approximately 77.42% of children with Class III malocclusion approximately 2 years after treatment. Unfavorable skeletal changes were mainly due to the greater protrusion of the mandible but maxillary protraction did have a certain degree of postimpact on the mandibular base. Protraction therapy does not fundamentally change the mode of maxillary growth in Class III subjects except for the advancement of the maxilla. Craniomaxillofacial region tend to restabilize after treatment and lead to skeletal growth rotation and more dentoalveolar compensation.

Is a non-radiological-assisted method valid for establishing crown-root relationships in an orthodontic set-up incorporating the roots? A retrospective study

INTRODUCTION

This study aimed to obtain information on the relationship between crown and root in terms of morphology - dimensions and crown-root angles -to be used for orthodontic set-ups without the use of radiological examinations.

MATERIAL AND METHODS

All the good quality CBCTs of patients obeying the eligibility criteria, from 2000 to 2015, were analysed. All teeth were analysed except for third molars. Six variables were evaluated: crown (CL) and root length (RL), crown width (CW), root width (RW), crown-root angles in both the frontal (CR-frontal) and sagittal plane (CR-sagittal). All teeth were divided into 3 groups according to number of root (single, two, three-rooted). The measurements were assessed with the Invivo professional software and then, subjected to correlation matrices and linear regression statistical analysis in order to find any significant correlations between crown and root measurements (α≤0.05).

RESULTS

Seventy-three out of 247 good quality CBCTs were assessed. Correlation matrices statistical analysis showed linear correlations for some variables investigated, especially for CW/RW pairing in all subgroups (r=0.81, r=0.70 and r=0.58 respectively for single-, two- and three-rooted) and CL/RL in the single-rooted subgroup (r=0.29). Subsequent linear regression analysis allowed to obtain information about roots starting from crown measurements by means of equations [RW=0.76+(0.73×CW) and RL=10.94+(0.25×CL) for single-rooted teeth; RL=1.11+(0.73×CW) and RW=0.99+(0.76×CW), respectively for single- and two-rooted teeth]. No linear correlation was found between crown measurements and C-R angular values.

CONCLUSION

It is possible to obtain root information starting from some crown measurements but these do not fulfil the need of minimal information to guarantee a perfect root position starting from that of crown.

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.

Dentofacial effects of miniscrew-anchored maxillary protraction on prepubertal children with maxillary deficiency: a randomized controlled trial

BACKGROUND

The introduction of bone-anchored maxillary protraction eliminated the side effects of facemask in the early treatment of patients with maxillary retrusion. This study aimed to evaluate the effects of miniscrew-anchored maxillary protraction (MAMP) and compare them with the growth changes in an untreated control group in growing patients with Class III malocclusion.

METHODS

Forty growing patients with Class III malocclusion and retrognathic maxilla were randomly allocated into two groups: treated and control groups. In the treated group, patients were treated with full-time intermaxillary Class III elastics (C3E) anchored by a hybrid hyrax (HH) in the maxilla and a bone-supported bar in the mandible. Protraction was stopped after obtaining a positive overjet. Cephalometric radiographs were acquired before and after the treatment. Data were statistically analyzed on an intention-to-treat basis. Intergroup comparisons were also made using analysis of covariance with the readings at T0 as a covariate.

RESULTS

Forty patients agreed to participate, and 30 of them completed the study (treated group, n = 17; control group, n = 13). The average treatment duration was 11.9 months. MAMP resulted in a significant maxillary advancement (A-VR, 4.34 mm) with significant control over the mandibular growth. No significant increase in the mandibular plane angle was found in the treated group compared with the control group. The upper and lower incisors showed significant protrusion in the treated group.

CONCLUSIONS

Within the limitations of this study and high attrition rate, the MAMP protocol can effectively increase maxillary forward growth with good control over the growth of the mandible antero-posteriorly and vertically.

Class III treatment with mini-implants anchorage in young adult patients: short and long-term results

INTRODUCTION

Class III malocclusion should be intercepted and treated at early age, to prevent the necessity of future complex and expensive procedures. The orthopedic facemask therapy has the goal to achieve skeletal changes, minimizing side effects on dentition. The use of skeletal anchorage, combined with Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) protocol, may be effective in treating a greater number of growing Class III patients.

OBJECTIVE

To summarize the existing evidence-based literature on Class III malocclusion treatment in young adult patients, and to illustrate its application and effectiveness, by presenting an emblematic case report.

CONCLUSION

The resolution of the present case, its long-term follow up, along with the studies conducted on a larger sample, demonstrate the effectiveness of the strategic combination of orthopedic and orthodontic treatments by using an hybrid rapid palatal expander and Alt-RAMEC protocol for treating Class III malocclusions in adult patients.

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.

Dentoskeletal changes due to rapid maxillary expansion in growing patients with tooth-borne and tooth-bone-borne expanders: A randomized clinical trial

OBJECTIVES

To compare, using cone-beam computed tomography, the dentoskeletal changes in rapid maxillary expansion with tooth-bone-borne (Hybrid Hyrax) and tooth-borne (Hyrax) appliances.

SETTING AND SAMPLE POPULATION

Forty-two patients who met the eligibility criteria (aged 11-14 years; transverse maxillary deficiency, posterior crossbite, and presence of upper first premolars and molars) were screened and allocated into two groups: HHG (treatment with Hybrid Hyrax) and HG (treatment with Hyrax).

MAIN OUTCOME MEASURES

The primary outcomes included nasomaxillary dimensional changes. CBCT was performed before and 3 months after the activation phase. Measurements were performed using Dolphin® . Baseline data were compared using one-way ANOVA. For intergroup comparison, ANCOVA was used to analyze the initial age, appliance activations (mm), and mid-palatal suture maturation data as covariates. Statistical significance was set at 5%.

RESULTS

The premolar region in HHG showed increased skeletal changes than in HG, with the difference being 1.5 mm (0.5; 2.6) in the nasal cavity (P = .004), 1.4 mm (0.3; 2.5) in the nasal floor (P = .019), and 1.1 mm (0.2; 2.1) in the maxilla (P = .022). The molar region in HHG showed increased skeletal changes with the difference being 0.9 mm (0.2; 1.5) in the nasal cavity (P = .005), and 0.9 mm (0; 1.8) in the maxilla (P = .042) than in HG. Premolar inclination was higher in HG.

CONCLUSION

Hybrid Hyrax showed more skeletal changes and fewer dental side effects, especially in the first premolar region. The amount of activation influenced the higher nasal skeletal changes in the Hybrid hyrax group.

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.

Treatment effects of maxillary protraction with palatal plates vs conventional tooth-borne anchorage in growing patients with Class III malocclusion

INTRODUCTION

Evaluate the treatment effects of maxillary protraction using palatal plates and compare them to those with conventional tooth-borne anchorage in growing patients with Class III malocclusion.

METHODS

Forty patients were divided into 2 groups according to the type of anchorage used: group 1 (n = 20; mean age, 10.5 ± 1.6 years; palatal plates) and group 2 (n = 20; mean age, 10.0 ± 1.2 years; tooth-borne appliances). Lateral cephalograms were taken before and after maxillary protraction. Skeletal, dental, and soft-tissue variables were measured. For statistical analysis, paired and independent t tests were performed.

RESULTS

Group 1 showed maxilla advancement by 2.3 ± 1.0 mm compared with group 2 by 0.9 ± 0.6 mm, and group 2 indicated clockwise rotation of the mandible, but there was no such clockwise rotation in group 1 (P <0.001). Group 1 had a less lingual inclination of the mandibular incisors than group 2 (IMPA, -1.0° ± 3.8° vs -3.8° ± 2.8°; P <0.05). There was no difference in soft-tissue changes between the 2 groups.

CONCLUSIONS

A facemask with palatal plate induced maxillary advancement with less mandibular clockwise rotation and dental movement than conventional tooth-borne anchorage. This modality can be used efficiently for maxillary protraction in growing patients with Class III malocclusion.

Skeletal expansion using a miniscrew-assisted rapid palatal expansion in a 50-year-old patient

This case report illustrates a nonsurgical treatment plan using a miniscrew-assisted rapid palatal expander (MARPE) in a 50-year-old patient with maxillary transverse deficiency. The MARPE appliance consisted of a conventional Hyrax expander anchored to 4 orthodontic miniscrews. The exact locations of the miniscrews were determined with virtual planning software. Cone-beam computed tomography (CBCT) scans were superimposed on the maxillary digital model, and 3-dimensional-printed surgical guides were used to accurately position the mini-implants. A slow expansion protocol was used, and the appliance was held in place during the entire treatment (almost 20 months). Pretreatment, postexpansion, and posttreatment CBCT scans show the parallel expansion obtained without dental torque compensation or bite opening. The posttreatment scan showed that a long period is required to complete the midpalatal suture mineralization. MARPE has proven effective in correcting transverse discrepancies, even in adults. However, posttreatment CBCT imaging showed incomplete ossification of the midpalatal suture, demonstrating that the retention period should be extended in some adult patients.

Evaluation of bone depth, cortical bone, and mucosa thickness of palatal posterior supra-alveolar insertion site for miniscrew placement

BACKGROUND

The use of palatal miniscrew offers the possibility to improve the effectiveness of orthodontic expansion devices. Palatal expanders supported by miniscrew can be applied with different clinical protocols. Some authors proposed the use of four palatal miniscrews during miniscrew-supported palatal expansion to maximize skeletal effects in young adults' treatment. However, bone availability decreases in the posterior paramedian palatal regions, making the positioning of the two-posterior paramedian palatal miniscrews challenging, when it is performed avoiding nasal cavities invasion. Some authors proposed miniscrews insertion in a specific region located laterally to the palatal process of the maxillary bone, and apically relatively to the dento-alveolar process. The aim of this study was to evaluate the bone thickness, cortical bone thickness, and mucosae depth of this anatomical site that, in this study, was defined as palatal posterior supra-alveolar insertion site.

RESULTS

The evaluation of bone availability of palatal posterior supra-alveolar insertion site at different antero-posterior levels showed that the maximum amount of total bone thickness was found between the second premolar and the first molar. At this level total bone, thickness is significantly (p < .05) greater compared to the other sagittal sites and it offers on average around 2 mm of extra bone depth for miniscrew placement. Cortical bone thickness is adequate for primary miniscrew stability. Overall, cortical bone thickness considered at different insertion sites showed significant statistically (p < .05) differences. The findings of this study showed that palatal mucosa is particularly thick with average values ranging from 4 to 7 mm, and its extension ultimately affects miniscrew length selection. Palatal mucosa thickness showed no clinically significant differences comparing different sagittal and vertical insertion sites. Data also showed that palatal mucosal thickness slightly significantly increases (p < .05) with the inclination of the insertion axis relative to the occlusal plane. Finally, study findings showed that vertical growth pattern can significantly affect considered outcomes (p < .05).

CONCLUSIONS

Palatal posterior supra-alveolar insertion site is an appropriate site for posterior insertion of palatal miniscrews. Considering high anatomical variation preliminary CBCT evaluation is important to achieve optimal miniscrew placement.

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

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

Do we pay for maxillary protraction? Evaluation of the effects of Alt-RAMEC protocol and face mask treatment on root development

OBJECTIVES

To evaluate root development of pediatric patients treated with Alt-RAMEC + Face mask therapy.

MATERIAL AND METHODS

The 19 subjects (9 girls, 10 boys; mean age: 8.6 ± 1.1 years) treated with Alt-RAMEC and a Petit-type face mask were included to the study. The cone-beam tomography (CBCT) records of these patients were used to quantify the root length. The root length measurements of 456 permanent teeth (maxillary-mandibular incisors, canines, premolars, and first molars) were performed at the beginning of the treatment (T0), after the Alt-RAMEC protocol (T1), and at the end of the face mask treatment (T2) using Planmeca Romexis software.

RESULTS

Tooth length values increased significantly in the maxillary teeth except the central incisors, left lateral incisor, the palatal root of the right first molar, and distal and palatinal roots of the left first molar (p < 0.05). Mandibular teeth also showed significant increase in the root length except mandibular central incisors and the distal root of left first molar (p < 0.05). The change in tooth lengths from T0 to T1 showed positive delta values. The comparison of the change in tooth lengths after the Alt-RAMEC protocol and after the face mask therapy showed that ∆T2-T1 was statistically significantly higher compared with ∆T1-T0 (p < 0.05).

CONCLUSIONS

Alt-RAMEC + Face mask therapy seem not to inhibit root development of maxillary and mandibular teeth in the mixed dentition.

CLINICAL RELEVANCE

These findings suggest that early Alt-RAMEC + Face mask interventions have not played a negative role in root development. However, further studies involving a control group need to be performed.

Space closure by miniscrew-assisted mesialization of an upper third molar and partial vestibular fixed appliance: A case report

This case report demonstrates how the use of skeletal anchorage and appropriate orthodontic biomechanics can be used to resolve even complex cases, reducing unwanted dental movements and allowing the use of a partial vestibular appliance. It describes the complete mesialization of the left upper third molar and space closure following extraction of tooth UR7, due to vertical fracture one year after previous endodontic therapy for caries. This therapeutic choice was conditioned by the need not to alter the good pre-existing interarch relationships, and above all by the patient's request to be treated conservatively, and therefore not to undergo prosthetic implant rehabilitation. The use of orthodontic miniscrews and the careful application of orthodontic biomechanics, based on both direct and indirect anchorage, enabled the treatment objectives to be achieved in a reasonable period of time with reduced treatment costs.

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

OBJECTIVE

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.

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Treatment effect of bone-anchored maxillary protraction in growing patients compared to controls: a systematic review with meta-analysis

OBJECTIVE

The aim of this systematic review was to determine which evidence level supports maxillary advancement after bone-anchored maxillary protraction (BAMP) in growing patients compared to controls.

SEARCH METHODS

PubMed, Cochrane, Embase, Scopus, and Web-of-Science databases were searched with no restrictions on publication status or year.

SELECTION CRITERIA

Prospective and retrospective human studies about BAMP, in at least three patients, were included. Authors were contacted when necessary, and reference lists of the included studies were screened.

DATA COLLECTION AND ANALYSIS

Two authors undertook independent data extraction with conflict resolution by a third author. Risks of bias were assessed. A meta-analysis for estimates of changes for ANB angle, Wits appraisal, and incisor to mandibular plane angle (IMPA) angle of BAMP treatment compared to control groups was performed.

RESULTS

A total of 449 articles were initially retrieved; 28 full-text articles met the inclusion criteria. Sample sizes ranged from 3 to 52 patients. There was heterogeneity in cephalometric outcomes reported, which prevented the comparison of certain outcomes. ANB angle improved more with BAMP in the maxilla combined with facemask (bone-anchored facemask, BAFM) compared to traditional facemask therapy: this was statistically but not clinically significant (0.2 degrees). No data are available for BAMP with skeletal anchorage in both jaws in combination with Class III elastics (bone-anchored Class III elastics, BAC3E). Likewise, no statistically significant differences in Wits appraisal were found (less than 1 mm). Lower incisor retroclination and facial height seemed to be better controlled with BAC3E compared to BAFM.

CONCLUSIONS

The level of evidence available to support the maxillary advancement effect after BAMP was low. Publications reporting results based on identical samples tended to suggest overly positive results of BAMP. The differences in sagittal correction between BAMP and traditional facemask therapy were small and of questionable clinical significance. Long-term follow-up results are not available and, therefore, much needed.

LIMITATIONS

Most articles had a low level of evidence and some included a historical control group.

REGISTRATION

PROSPERO database number CRD42015023366.

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.

Effectiveness of Tongue Crib Combination Treating Severe Skeletal Angle Class III Malocclusion in Mixed Dentition

Objective

To evaluate the treatment effects of tongue crib combination for treating severe skeletal Angle class III malocclusion in mixed dentition by X-ray cephalometric analysis.

Materials and methods

A sample of 22 patients with severe skeletal Angle class III malocclusion of deficiency maxilla and overgrown mandible in mixed dentition was prospectively collected and equally divided into two groups. The patients (males 6 and females 5; mean age 8.35 ± 1.6 years) in the study group were treated with tongue crib combination, and the untreated patients (females 5, males 6; mean age 8.12 ± 1.3 years) served as the control group. X-ray cephalometric films were measured before and after treatment for comparing the change of occlusion, maxilla, mandible, and soft tissue. A paired t-test was used by SPSS 21.0 statistical software. The intragroup data were compared by using the Wilcoxon test, and intergroup data were compared by using the Mann–Whitney U test (p < 0.05).

Results

In the study group, all patients got a favorable facial profile. Anterior and posterior teeth crossbite and upper and lower first molars relationships were improved. In cephalometric measurement, significant changes were noted in the maxillary skeletal component. The significant forward growth of the maxilla exhibited in a statistical increase of SNA, ANS-PNS, Wits appraisal, p < 0.05. The mandible revealed slightly posterior rotation by no significant decrease in SNB and no change Co-Gn. After 1-year of retention, the changes of the teeth showed self-correction and facial profile improved further. Regarding vertical changes, maintenance of growth was shown a small non-significant increase of FMA, N-Me, and ANS-Me. There is a significant difference from those in the control group (p < 0.05).

Conclusion

Tongue crib combination is an effective device for the patients in the growing period with skeletal Angle class III malocclusion by improving the maxillary growth and limiting the mandibular growth.

How to cite this article

Zhao W, Chen Y, Kyung H-M, et al. Effectiveness of Tongue Crib Combination Treating Severe Skeletal Angle Class III Malocclusion in Mixed Dentition. Int J Clin Pediatr Dent 2020;13(6):668–676.

Assessment of stiffness and load deflection of orthodontic miniscrews used for palatal anchorage: An in vitro biomechanical study

OBJECTIVE

The purpose of this study was to evaluate the biomechanical properties of miniscrews of 5 different lengths, 2 different diameters, and different combinations of insertion used for palatal skeletal anchorage.

MATERIALS AND METHODS

Twenty-four different combinations of a total of 120 miniscrews of two different diameters (2.0mm and 2.3mm) and five different lengths (9mm, 11mm, 13mm and 15mm) were tested at different angles of insertion (90° and 45°) and distances from a synthetic bone block (3mm, 5mm, 7mm). Samples were fixed in an Instron Universal Testing Machine and a load was applied in single cantilever mode to the neck of each miniscrew. The stiffness and maximum load before permanent deformation were recorded. Model-based recursive partitioning testing (CART) was used to evaluate differences between groups.

RESULTS

Significantly higher forces were necessary to deform miniscrews of diameter 2.3mm than those of 2.0mm, those inserted at an angle of 45° with respect to 90°, and at smaller distances between the miniscrew neck and block; in addition, the maximum load and stiffness increased with increasing screw length.

CONCLUSION

This in vitro experimental study showed strong correlations between deformation load and miniscrew geometry, insertion angle and distance from the synthetic block, results that should be considered when planning miniscrew insertion in order to reduce the risk of unwanted fracture.

Early class III treatment with hybrid rapid palatal expander combined with facemask

BACKGROUND

Class III patients are characterized by a deficiency of the maxilla and/or a prognathism of the mandible and require early treatment.

DIAGNOSIS

This case report describes the treatment of a 5-year-old patient with a skeletal class III relationship, a significant mandibular symphysis deviation towards the right side and a different height of the mandibular angles.

MANAGEMENT AND OUTCOME

The patient was treated with rapid maxillary expander combined with miniscrew, facemask and aligners. A functional and aesthetic occlusion in an improved facial profile was established at the end of the orthodontic treatment. Pre-treatment, post-treatment and one year retention records for the patient are presented.

DISCUSSION

Class III patients require early treatment in order to optimize the traditional expander effects; subsequently hybrid anchorage allowed to maximize skeletal advancement. In addition, loss of space for the erupting teeth and dento-alveolar tipping were avoided. The good results of the phase I treatment and of the active retainer meant that a complex case would become relatively simple at the phase II treatment.

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.

A New Methodology for the Digital Planning of Micro-Implant-Supported Maxillary Skeletal Expansion

INTRODUCTION

Miniscrew-assisted rapid palatal expansion (MARPE) appliances utilize the skeletal anchorage to expand the maxilla. One type of MARPE device is the Maxillary Skeletal Expander (MSE), which presents four micro-implants with bicortical engagement of the palatal vault and nasal floor. MSE positioning is traditionally planned using dental stone models and 2D headfilms. This approach presents some critical issues, such as the inability to identify the MSE position relative to skeletal structures, and the potential risk of damaging anatomical structures.

METHODS

A novel methodology has been developed to plan MSE position using the digital model of dental arches and cone-beam computed tomography (CBCT). A virtual model of MSE appliance with the four micro-implants was created. After virtual planning, a positioning guide is virtually designed, 3D printed, and utilized to model and weld the MSE supporting arms to the molar bands. The expansion device is then cemented in the patient oral cavity and micro-implants inserted. A clinical case of a 12.9-year-old female patient presenting a Class III malocclusion with transverse and sagittal maxillary deficiency is reported.

RESULTS

The midpalatal suture was opened with a split of 3.06 mm and 2.8 mm at the anterior and posterior nasal spine, respectively. After facemask therapy, the sagittal skeletal relationship was improved, as shown by the increase in ANB, A-Na perpendicular and Wits cephalometric parameters, and the mandibular plane rotated 1.6° clockwise.

CONCLUSION

The proposed digital methodology represents an advancement in the planning of MSE positioning, compared to the traditional approach. By evaluating the bone morphology of the palate and midface on patient CBCT, the placement of MSE is improved regarding the biomechanics of maxillary expansion and the bone thickness at micro-implants insertion sites. In the present case report, the digital planning was associated with a positive outcome of maxillary expansion and protraction in safety conditions.

An asymmetric magnetic reverse Twin-block applian ce for the treatment of a skeletal Class III malocclusion: a case report

Background

The treatment of a skeletal Class III malocclusion with accompanying mandibular asymmetry is an orthodontic challenge. A skeletal Class III may be associated with a retrognathic maxilla, a prognathic mandible and a mandibular asymmetry can be of dental or skeletal origin or in various combinations. Timely treatment with appropriate biomechanics is crucial for an acceptable and stable result.

Aims

The aim of this article was to introduce a clinically effective asymmetric magnetic reverse Twin-block appliance (AMRTB) for growth modification treatment of an 11-year-old girl who presented with a skeletal Class III malocclusion and accompanying mandibular asymmetry.

Methods

The treatment was comprised of two phases, the first of which was growth modification using the AMRTB for the stimulation of maxillary growth, restraint of mandibular growth, and improvement of the mandibular asymmetry. This was followed by a second phase involving full fixed appliances to optimise the interdigitation and occlusion.

Results

The skeletal Class III relationship and mandibular asymmetry was successfully corrected after two years of treatment. A good facial appearance and pleasing smile aesthetics were achieved. The treatment result was stable after six years of follow-up.

Conclusion

This case demonstrated that the AMRTB was a clinically effective appliance for growth modification treatment in patients with a skeletal Class III malocclusion and mandibular asymmetry.

Early treatment of Class III malocclusion with facemask therapy

The facemask is a widely used device in the treatment of Class III malocclusion and is intended to anteriorly displace the superior maxilla or stimulate its growth in that direction. The main goal of this study was to evaluate the effects of treatment using orthopedic maxillary expansion with facemask therapy in patients with Class III malocclusion. Sixty-four patients, with a mean age of 8.14 ± 1.18 years at the start of treatment and a mean age of 9.78 ± 1.19 years at the end, were treated using orthopedic maxillary expansion and associated facemask therapy. The patients were evaluated using lateral head teleradiography before and after treatment, and the differences were analyzed. In addition, binary logistic regression was used as a model for predicting successful treatment. When comparing the changes achieved by treatment, statistically significant favorable changes were found at the skeletal level. Furthermore, an improvement in the airways at all levels was detected. Orthopedic maxillary expansion associated with facemask therapy has proven effective in treating early skeletal Class III malocclusion.