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

Dentofacial and skeletal effects of two orthodontic maxillary protraction protocols: bone anchors versus facemask

BACKGROUND

Maxillary retrognathia and/or mandibular prognathia are resulting in class III malocclusion. Regarding orthodontic class III malocclusion treatment, the literature reports several treatment approaches. This comparative clinical study investigated two maxillary protraction protocols including bone anchors and Delaire type facemask.

METHODS

Cephalometric radiographs of n = 31 patients were used for data acquisition. The patients were divided into two groups according to their treatment protocol: bone anchored protraction (n = 12, 8 female, 4 male; mean age 11.00 ± 1.76 years; average application: 13.50 ± 5.87 months) and facemask protraction (n = 19, 11 female, 8 male; mean age 6.74 ± 1.15 years; average application: 9.95 ± 4.17 months). The evaluation included established procedures for measurements of the maxilla, mandibula, incisor inclination and soft tissue. Statistics included Shapiro-Wilk- and T-Tests for the radiographs. The level of significance was set at p < 0.05.

RESULTS

The cephalometric analysis showed differences among the two groups. SNA angle showed significant improvements during protraction with bone anchors (2.30 ± 1.18°) with increase in the Wits appraisal of 2.01 ± 2.65 mm. SNA angle improved also during protraction with facemask (1.22 ± 2.28°) with increase in the Wits appraisal of 1.85 ± 4.09 mm. Proclination of maxillary incisors was larger in patients with facemask (3.35 ± 6.18°) and ML-SN angle increased more (1.05 ± 1.51°) than in patients with bone anchors. Loosening rate of bone anchors was 14.58%.

CONCLUSIONS

Both treatment protocols led to correction of a class III malocclusion. However, this study was obtained immediately after protraction treatment and longitudinal observations after growth spurt will be needed to verify the treatment effects over a longer period. The use of skeletal anchorage for maxillary protraction reduces unwanted side effects and increases skeletal effects needed for class III correction.

The effectiveness of bone anchored maxillary protraction (BAMP) in the management of class III skeletal malocclusion in children aged 11-14 years compared with an untreated control group: A multicentre two-arm parallel randomised controlled trial

OBJECTIVE

To evaluate the effectiveness of bone anchored maxillary protraction (BAMP) in the management of class III skeletal malocclusion in children aged 11-14 years compared with an untreated control group in terms of perceived need for orthognathic surgery, skeletal and dental change, and psychological impact.

DESIGN

A multicentre two-armed parallel randomised controlled trial.

SETTING

Six UK hospital orthodontic units.

METHODS

A total of 57 patients were randomly allocated into either the BAMP group (BAMPG) (n = 28) or a no treatment control group (CG) (n = 29).

OUTCOMES

Data collection occurred at registration (DC1),18 months (DC2) and 3 years (DC3), where skeletal and dental changes were measured from lateral cephalograms and study models. Oral Aesthetic Subjective Impact Score (OASIS) and Oral Quality of Life (OHQOL) questionnaires were used to assess the psychological impact of treatment.

RESULTS

The mean age was 12.9 ± 0.7 years and 12.6 ± 0.9 years in the BAMPG and CG, respectively. At DC2, the BAMPG achieved a class III ANB improvement of +0.6° compared with -0.7° in the CG (P = 0.004). The overjet improvement was +1.4 mm for the BAMPG and -0.2 mm for the CG (P = 0.002). There was no evidence of any other group differences for the other skeletal or dental cephalometric outcomes (P > 0.05) or the questionnaire data (OASIS P = 0.10, OHQOL P = 0.75). At DC2, the 18-month follow-up, 22% of the BAMPG achieved a positive overjet. At the 3-year follow-up (DC3), fewer participants in the BAMPG were perceived to need orthognathic surgery (48%) compared with 75% of participants in the CG (P = 0.04), with an odds ratio of 0.31 (95% confidence interval = 0.10-0.95).

CONCLUSION

The BAMP technique did not show any social or psychological benefits; however, the skeletal class III improvement in ANB and the overjet change were sufficient to reduce the perceived need for orthognathic surgery by 27% compared with the CG.

Oral Health Assessment in Cleft Lip & Palate Patients During Orthodontic Treatment for Maxillary Protraction: A Periodontal & Microbiological Study

OBJECTIVE

To assess the oral health status and microbiota of subgingival plaque in patients with surgically repaired cleft lip and palate (CLP) during orthodontic treatment for maxillary protraction with two different orthodontic appliances.

DESIGN

Randomized controlled trial.

SETTING

Institutional.

PARTICIPANTS

A total of 90 patients with surgically repaired Unilateral Cleft Lip and Palate, out of initially enrolled 120 patients, were divided into 3 groups: experimental group I, experimental group II and control group, with 30 subjects each. Patients with a history of oral prophylaxis in last 6 months or antibiotic therapy within 3 months were excluded from the study.

INTERVENTIONS

Bone Anchored Maxillary Protraction was done in experimental group I, while facemask with acrylic occlusal splint was used for maxillary protraction in experimental group II and no orthodontic intervention in control group.

MEAN OUTCOME MEASURES

Plaque Index (PI), Gingival Index (GI), Gingival Bleeding Index (GBI), Probing Depth (PD), and microbiota of subgingival plaque (P. gingivalis, P. intermedia, Veillonella and Capnocytophaga) were compared at baseline (T0) and after 8 months (T1).

RESULTS

The PI, GI, GBI and PD were observed to be significantly higher in experimental group II followed by experimental group I as compared to control group at 8 months interval (P < .001). The microbiota counts increased significantly in experimental group II and experimental group I (P < .001), as compared to control group.

CONCLUSION

Maxillary protraction with facemask and bone plates was found to be a better alternative than facemask with occlusal splint, considering the overall oral health of patients with CLP.

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.

Treatment of maxillary hypoplasia with bone anchored maxillary protraction (BAMP) - A case report

Early diagnosis and treatment is known to be beneficial in Class III malocclusions secondary to maxillary hypoplasia. However, success of treatment largely depends on the patient's compliance and thus, appropriate choice of treatment, appliance and the age for interception plays an important role. Bone anchored maxillary protraction is one such approach presented in this case report for a 13 years old boy who reported with the chief complaint of lower front teeth visibility during speech and smiling. On examination his molars were in Angle's Class III relation, anterior crossbite and deep bite with unerupted maxillary canines. Orthodontic treatment was begun for deep bite correction and for creating space for the maxillary canines, followed by surgical intervention for placement of bone anchored miniplates. Protraction was done for 14 months and the total treatment time was 20 months. Improvement in the patient's profile, aesthetics and function was achieved with well aligned arches.

An orthotropic continuum model with substructure evolution for describing bone remodeling: an interpretation of the primary mechanism behind Wolff's law

We propose a variational approach that employs a generalized principle of virtual work to estimate both the mechanical response and the changes in living bone tissue during the remodeling process. This approach provides an explanation for the adaptive regulation of the bone substructure in the context of orthotropic material symmetry. We specifically focus upon the crucial gradual adjustment of bone tissue as a structural material that adapts its mechanical features, such as materials stiffnesses and microstructure, in response to the evolving loading conditions. We postulate that the evolution process relies on a feedback mechanism involving multiple stimulus signals. The mechanical and remodeling behavior of bone tissue is clearly a complex process that is difficult to describe within the framework of classical continuum theories. For this reason, a generalized continuum elastic theory is employed as a proper mathematical context for an adequate description of the examined phenomenon. To simplify the investigation, we considered a two-dimensional problem. Numerical simulations have been performed to illustrate bone evolution in a few significant cases: the bending of a rectangular cantilever plate and a three-point flexure test. The results are encouraging because they can replicate the optimization process observed in bone remodeling. The proposed model provides a likely distribution of stiffnesses and accurately represents the arrangement of trabeculae macroscopically described by the orthotropic symmetry directions, as supported by experimental evidence from the trajectorial theory.

Maxillary Protraction: A Bibliometric Analysis

OBJECTIVES

The aim of this analysis was to investigate the historical development, current status, and research hot spots related to maxillary protraction in the treatment of maxillary hypoplasia.

METHODS

The term "TS = maxillary protraction" was used to search for articles in the Web of Science Core Collection at the library of Capital Medical University. The results were analysed using CiteSpace6.2.R1 software, including the examination of annual publication trends and analysis of author, country, institution, and keywords.

RESULTS

A total of 483 papers were included in this study. The annual publications showed an overall increasing trend. The top 5 authors with the most published papers were Lorenzo Franchi, Tiziano Baccetti, Seung-Hak Baek, Paola Cozza, and U Hagg. The top 5 countries with the highest publication counts were the US, Turkey, South Korea, Italy, and China. The top 5 institutions in terms of the number of published papers were the University of Florence, the University of Michigan, Kyung Hee University, Seoul National University, and Gazi University. The top 3 journals with the most citations were the American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, and the European Journal of Orthodontics. Furthermore, "Maxillary protraction," "Class III malocclusion," and "Maxillary expansion" were the most common keywords.

CONCLUSIONS

The effective age range for maxillary protraction has been expanded with the introduction of skeletal anchorage and the combination of maxillary expansion and protraction. Skeletal anchorage offers significant advantages over dental anchorage, but there is a need for further research to further substantiate its stability and safety. In recent years, the positive effects of maxillary protraction on the nasopharyngeal area have been well established, but its impact on the oropharyngeal area remains a topic of debate. Therefore, it is crucial to conduct further investigations into the effects of maxillary protraction on the oropharyngeal area and explore the factors that influence different outcomes.

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.

Impact of bone-anchored maxillary protraction on the quality of life of subjects with complete unilateral cleft lip and palate

INTRODUCTION

This study aimed to evaluate the influence of bone-anchored maxillary protraction (BAMP) on the oral health-related quality of life (OHRQOL) in subjects with complete unilateral cleft lip and palate (UCLP) and moderate-to-severe maxillary deficiency.

METHODS

A longitudinal observational study was conducted with a sample of 20 patients (13 males, 7 females) aged 10-14 years (mean age, 11.8 years) with Goslon 3, 4, and 5. To assess the patient's perception of their OHRQOL, the Quality of Life Questionnaire for Orthosurgical Patients was administered in 2 stages: after the installation of the protraction plates (T1) and 18 months after the protraction therapy started (T2). The questionnaire was composed of 4 domains, distributed over 22 questions: social aspects, facial esthetics, oral function, and awareness of facial deformity.

RESULTS

The treatment protocol improved the OHRQOL in 75% of the patients who presented UCLP. The domain social aspects of the deformity were the only one that showed a significant difference from T1 to T2 and indicated an improvement in self-esteem. The girls had worse OHRQOL than boys at T1, which was statistically significant only for the domains of social aspects of deformity and awareness of deformity. After BAMP therapy, the effect size indicated a larger change in OHRQOL in girls than in boys.

CONCLUSIONS

BAMP therapy positively impacted the OHRQOL and self-esteem of patients with UCLP during adolescence.

Effects produced by the facemask with and without skeletal anchorage for the orthopaedic treatment of Class III malocclusion in growing patients: a systematic review and meta-analysis of RCTs

BACKGROUND

Skeletally anchored facemask has been proposed to maximize skeletal effects and minimize dental effects in the treatment of Class III malocclusion in growing patients.

OBJECTIVE

To compare the dento-skeletal effects produced by the facemask with or without skeletal anchorage for the treatment of Class III malocclusion in growing patients.

MATERIALS AND METHODS

PubMed, Cochrane Library, Scopus, Embase, Web of Science, and OpenGrey were used for the electronic search without language, publication status, and year restrictions. Only RCTs were included. Inclusion criteria were: growing patients (age under 18 years) with Class III malocclusion, with indications for treatment with the facemask. Data were extracted by two independent reviewers. GRADE statement was executed. The mean of differences (MD) and the risk ratio (RR) were used.

RESULTS

Three articles with a total of 123 patients were included. One article was at low risk of bias while two were at high risk of bias. There were no significant differences between the two groups in ANB angle, Wits appraisal, SNB angle, and SN-MP angle. SNA angle was significantly increased in the skeletally anchored facemask (pooled MD = 0.80 favouring skeletal anchorage, 95% CI from 0.29 to 1.31, P = 0.002, I2 = 12 per cent, three studies, GRADE moderate). The U1-SN angle was significantly reduced in the skeletally anchored facemask (pooled MD = -5.91 favouring skeletal anchorage, 95% CI from -7.64 to -4.27, P < 0.00001, I2 = 0 per cent, two studies, GRADE moderate). There were significantly less complications in tooth-anchored facemask (pooled RR = 7.98 favouring dental anchorage, 95 per cent CI from 1.04 to 61.27, P = 0.05, I2 = 0 per cent, two studies, GRADE low).

LIMITATIONS

Few RCTs (three) were included, and two studies were at high risk of bias. There were no long-term RCTs comparing skeletally anchored facemask with dental-anchored facemask. Only Asiatic patients were included in this systematic review.

CONCLUSIONS

Skeletally anchored facemask was associated to a greater increase of SNA angle at the end of treatment though clinically not significant. Facemask with skeletal anchorage determined a reduced inclination of maxillary incisors compared to dental-anchored facemask with greater risks of complications.

REGISTRATION

PROSPERO register (CRD42020221982).

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.

Bone-anchored maxillary protraction (BAMP): A review

INTRODUCTION

Protraction therapy for maxillary deficiency in the treatment of skeletal class III malocclusion involves the use of facemask. Conventionally facemask has been anchored to the maxillary dentition, which is responsible for some of the counter-productive effects of facemask therapy including backward and downward rotation of the chin, increase in the lower anterior facial height, proclination of maxillary incisors, retroclination of mandibular incisors apart from mesialization of maxillary molars with extrusion and decreased overbite.

AIM

The aim of this article is to highlight the nuances of Bone-Anchored Maxillary Protraction (BAMP) including a literature review, which is comprehensive and narrative and comparing the different techniques involved such as type 1 BAMP versus type 2 BAMP and BAMP versus facemask.

MATERIALS AND METHODS

A computerized search was performed in electronic databases such as PubMed, PubMed Central, Cochrane, Embase, DOAJ, and Google scholar using key words such as "bone-anchored maxillary protraction" and "BAMP." The search was confined to articles in English published till March 2021. Forty-seven case-controlled, cross-sectional, retrospective and prospective studies, as well as systematic reviews and meta-analysis were included in this article, which were limited to human subjects. A hand search of the reference lists of the included articles was also carried out to include missed out articles.

CONCLUSION

To overcome these drawbacks, BAMP was introduced, which causes both maxillary protraction, restraint of mandibular growth with minimal dentoalveolar changes. BAMP is used widely nowadays in the treatment of skeletal class III malocclusion.

Management of Class III Extraction with the Miniscrew-Supported Orthodontic Pseudo-Ankylosis (MSOPA) Using Direct Tads

The aim of the present study is to represent the orthodontic treatment of a young patient with a skeletal Class III malocclusion(Wits Appraisal −9 mm), in which the extractions of the first lower premolars were performed to obtain a class III camouflage using direct temporary anchorage devices (TADs). The patient reported a history of three years of orthodontic treatment at another clinic and the radiographic evaluation revealed an important impairment of the upper root incisors. A treatment was performed with a fixed appliance in the upper and lower arches using an archwire sequence of 0.16 CuNiTi, 19 × 25 CuNiTi, 19 × 25 SS and was carried out in 18 months. Post-treatment records of our patient show a control of facial esthetics from the frontal and lateral perspectives, with a harmonious soft-tissue profile. A Class I canine was achieved and her overbite and overjet were normalized by retracting the mandibular anterior teeth and carrying out a bodily mesialization of the posterior sector into the extraction space. In conclusion, the “pseudoankylosis system” used in this case allowed the desired result to be achieved with minimal change to the lower incisal inclination and without overloading the anterior upper and lower sectors, thus reducing the risk of further root resorption and patient compliance.

The biological sex lens on early orthopaedic treatment duration and outcomes in Class III orthodontic patients: a systematic review

BACKGROUND

Treatment outcomes for Class III orthopaedic treatment are highly unpredictable and dependent on the timing of interception, age, and biological sex.

OBJECTIVE

This systematic review aimed to assess the effects of sex dimorphism on outcomes and duration of orthopaedic treatment for Class III malocclusion in young children.

SEARCH METHODS

Unrestricted search in six electronic databases until May 2021 was conducted. Supplemented by search in resources for published, unpublished literature, and ongoing trials.

SELECTION CRITERIA

Randomized and non-randomized controlled trials reporting the use of Class III growth modification appliances, with baseline and outcome data for both sexes, were included.

DATA COLLECTION AND ANALYSIS

Study selection and data extraction were performed blindly and in duplicate by two reviewers. ROBINS-I, Cochrane Risk of Bias, and GRADE tools were used for certainty assessment.

RESULTS

A total of 2429 records were screened. Four trials fulfilled the inclusion criteria, one was a randomized clinical trial (RCT) comparing facemask and facemask with mini-screw. Two clinical trials evaluated the effects of facemask appliance, one had a control group, another was prospective non-controlled. One compared the effects of the maxillary protraction bow appliance to a no treatment control. Two of the clinical trials were appraised as low and one was appraised as high risk of bias. The overall certainty of the available evidence was assessed as moderate. There was significant clinical heterogeneity in terms of methodology, type of intervention, and the measured outcomes, precluding a meta-analysis.

CONCLUSIONS

Minimal variations in sagittal, vertical, and dentoalveolar post-treatment cephalometric changes were reported between sexes. The available evidence is unclear to support these variations. Long-term-powered RCTs assessing cephalometric outcomes between sexes until the end of growth spurt and without pooling are not available, therefore, much needed.

REGISTRATION

PROSPERO database number CRD42020185797.

Comparative efficacy of the bone-anchored maxillary protraction protocols for orthopaedic treatment in skeletal Class III malocclusion: A Bayesian network meta-analysis

OBJECTIVE

To compare the treatment effects of five bone-anchored maxillary protraction protocols (BAC3E, BAMP, BARME-FM, BARME-ME, SAFM) for skeletal Class III malocclusion.

METHODS

We conducted a systematic literature search through CENTRAL, EBSCO, PubMed and Web of Science and included the randomized controlled trials and clinical controlled trials, which met the criteria. A Bayesian network meta-analysis (NMA) for SNA, SNB, ANB, SN-MP and Wits appraisal was performed in R software using a random consistency model. The additional analyses included node-splitting analysis, statistical heterogeneity analysis, sensitivity analysis and ranking probability by SUCRA.

RESULTS

A total of 598 articles were initially obtained; 13 articles involving 482 individuals were eventually included. Among the five bone-anchored maxillary protraction protocols, the largest increment in SNA and Wits appraisal was observed in the BAMP group and BAC3E group, respectively; the SAFM, BAC3E and BAMP groups showed similar capability in terms of changes of ANB; least clockwise rotation of the mandible was found in the BARME-ME group, followed by the BAMP group; dental compensation appears to be most pronounced in the BAC3E group; and intermaxillary traction seems to reduce the lingual inclination of lower incisors and even cause labial inclination.

CONCLUSIONS

The SAFM, BAMP and BAC3E groups seem to be advantageous in the improvement of the maxillo-mandibular relationship, followed by the BARME-FM and BARME-ME groups. The findings of this study should be interpreted with caution as only short-term effects were compared and the quality of evidence ranged from very low to moderate. More RCTs with high-quality and long-term investigation are needed.

Sutural deformation during bone-anchored maxillary protraction

Introduction

Bone-anchored maxillary protraction (BAMP) is an emerging treatment option for orthopedic correction of maxillary deficiency in young patients. Compared to reverse pull headgear (RPHG), it is believed that forces generated during BAMP result in greater circum-maxillary sutural separation, mandibular retrusion, and improved maxillary protraction. Mechanical loading of the circum-maxillary sutures during BAMP is still poorly understood.

Methods

20 ex-vivo pig heads were used. Miniplates and molar tubes were installed like clinical procedures. A series of five 200 ​g-force (gf) elastics were applied on the right and left side until 1000gf were reached. Strain gauges were installed across the zygomatico-maxillary (ZMS), zygomatico-temporal (ZTS), and nasofrontal suture (NFS). Differential variable reluctance transducers (DVRTs) were installed across the ZTS. Deformation of the sutures during BAMP and RPHG was measured and compared.

Results

Higher average sutural deformation of the ZTS and ZMS was seen in BAMP than RPHG: 36.6 ​± ​20.6με vs 18.0 ​± ​12.4με and 54.7 ​± ​28.5με vs 12.5 ​± ​14.8με, respectively. Similarly, higher NFS deformation was seen in BAMP (18.4 ​± ​12.9με vs. -0.8 ​± ​12.0με). DVRT data showed higher ZTS separation in BAMP than RPHG (6.3 ​± ​5.2 ​μm vs. 1.7 ​± ​2.1 ​μm). These differences were all statistically significant using the Wilcoxon-signed rank test.

Conclusion

Both RPHG and BAMP forces separate the ZTS and ZMS. BAMP resulted in higher levels of sutural separation at the ZTS and ZMS by 2- and 5-fold, respectively.

Miniplate-anchored maxillary protraction in adolescent patients with cleft lip and palate: A literature review of study design, type and protocol, and treatment outcomes

OBJECTIVE

To review the study design, type, protocol, and treatment outcomes of miniplate-anchored maxillary protraction (MAMP) in adolescent patients with unilateral or bilateral cleft lip and palate.

SETTING/SAMPLE POPULATION

Five retrospective and two prospective studies (n = 138 patients) were selected as per the inclusion criteria.

MATERIALS AND METHODS

The study design, type, protocol of MAMP and the amount of skeletodental change were investigated.

RESULTS

Two studies adopted type 1 (two miniplates at the infrazygomatic crest with a facemask), four studies adopted type 2 (four miniplates at the infrazygomatic crest and mandibular symphysis and use of intermaxillary elastics), and one study compared the two types. The mean start age was older than 10 years except one study. The mean duration was less than 1 year in two studies, between 1 and 2 years in three studies, and more than 2 years in two studies. The type 1 used 500 g/side for 12-14 h/d, and the type 2 used three increase methods (100, 200, 250 g/side; 75, 150, 250 g/side; 150, 200, and 250 g/side) for 24 h/d. The ranges of A point advancement were 0.5°-4.2° in ΔSNA and 1.7-5.6 mm in ΔA-vertical reference plane, respectively. The ranges of rotation of the palatal plane, occlusal plane, and mandibular plane were -1.5° to 2.0°, -2.0° to 2.0°, -1.5° to 3.2°, respectively. The increase of overjet was ranged from 2.3 to 5.8 mm.

CONCLUSION

The MAMP therapy is effective for the correction of maxillary hypoplasia in adolescent cleft patients despite different types and protocols.

Immediate and late follow-up effects of class III early correction in cleft lip and palate patients treated with maxillary protraction

Abstract Introduction There is no consensus about the immediate and latte follow-up effects of maxillary protraction in cleft lip and palate patients. Objective To evaluate the stability of Class III early treatment in cleft lip and palate patients through maxillary expansion and protraction. Material and method The sample consists in three lateral cephalometric radiographs of 28 patients (mean pre-treatment age of 6.7±1.8 years) who presented cleft lip and palate and were treated with maxillary expansion and Petit facial mask. The angular (SNA, SNB, ANB, SN.GoGn, FMA, Z Angle) and linear (overjet, Co-A, Co-Gn, Nperp-A, Nperp-Pg, AO-BO) cephalometric measures were evaluated through the Dolphin® software, in three moments: T0 (initial), T1 (after treatment), and T2 (follow-up). Data were submitted to the analysis of variance (ANOVA) and Tukey-Kramer test. The correlation between cephalometric measures and patient’s age was determined by Pearson’s chi-squared test. Result The SNA, ANB, and AO-BO measures increased considerably (p<0.05), and they did not present any differences compared to the initial ones after the follow-up time. The overjet measure increased (p<0.05) after treatment and, even with its decrease at the follow-up time, it was still higher than at the beginning (p<0.05). The Z angle showed improvement with treatment and remained stable at the follow-up time. Conclusion After treatment (maxillary expansion associated with protraction), there was a skeletal pattern improvement. During the follow-up period, those alterations decreased to a measure close to the beginning. There was an improvement in the dental pattern and facial profile that continued in the follow-up period.