Three-dimensional comparison of bone-borne and tooth-bone-borne maxillary expansion in young adults with maxillary skeletal deficiency.

OBJECTIVE: To compare the transverse dental and skeletal changes in patients treated with bone-anchored palatal expander (bone-borne, BB) compared to patients treated with tooth and bone-anchored palatal expanders (tooth-bone-borne, TBB) using cone-beam computer tomography (CBCT) and 3D image analysis. METHODS: The sample comprised 30 patients with transverse maxillary discrepancy treated with two different types of appliances: bone-borne (Group BB) and tooth-bone-borne (Group TBB) expanders. CBCT scans were acquired before (T1) and after completion of maxillary expansion (T2); the interval was 5.4 ± 3.4 and 6.2 ± 2.1 months between the T1 and the T2 scans of Group TBB (tooth-bone-borne) and Group BB (bone-borne), respectively. Transverse, anteroposterior and vertical linear and angular three-dimensional dentoskeletal changes were assessed after cranial base superimposition. RESULTS: Both groups displayed marked transverse skeletal expansion with a greater ratio of skeletal to dental changes. Greater changes at the nasal cavity, zygoma and orbital levels were found in Group BB. A relatively parallel sutural opening in an anterior-posterior direction was observed in Group TBB; however, the Group BB presented a somewhat triangular (V-shaped) opening of the suture that was wider anteriorly. Small downward-forward displacements were observed in both groups. Asymmetric expansion occurred in approximately 50% of the patients in both groups. CONCLUSION: Greater skeletal vs dental expansion ratio and expansion of the circummaxillary regions were found in Group BB, the group in which a bone-borne expander was used. Both groups presented skeletal and dental changes, with a similar amount of posterior palate expansion. Asymmetric expansion was observed in both groups.

Assessment of the bone thickness of the palate on cone-beam computed tomography for placement of miniscrew-assisted rapid palatal expansion appliances.

INTRODUCTION: The correction of maxillary transverse discrepancy is achieved by means of rapid maxillary expansion, which may be performed by conventional or surgically-assisted rapid maxillary expansion, and more recently, by miniscrew-assisted rapid palatal expansion (MARPE). This study assessed the bone thickness of the palate on cone-beam computed tomography (CBCT) images for placement of mini-implants and anchorage of MARPE. METHODS: The sample consisted of 223 CBCT scans from patients of both genders (137 females and 86 males) aged ≥18 years. By using the Image Studio software (Anne Solutions, São Paulo, Brazil), measurements of the bone thickness of the palate were performed bilaterally, as follows: in the axial plane, the bone thicknesses were determined in the anterior region (distal face of the first premolars) and the posterior region (distal face of the first molars), at 3 mm and 6 mm laterally to the midpalatal suture. So in the sagittal plane, the bone thicknesses of the palate were measured in these placements from the palatal cortical to the nasal floor cortical in the anterior region at 30°, 45°, and 90°. In the posterior region, the bone thickness was determined only at 90°. The statistical tests used were the Kruskal-Wallis H test (analysis of variance on ranks) with Dunn's post-hoc test and Mann-Whitney U test (P <0.05). RESULTS: The bone thickness of the palate in the anterior region varied from 8.57 mm in women to 11.28 mm in men at 3 mm from the midpalatal suture and from 7.99 mm in women to 10.47 mm in men at 6 mm for 30°; from 6.35 mm in women to 9.28 mm in men at 3 mm from the midpalatal suture and from 6.20 mm in women to 8.88 mm in men at 6 mm for 45°; from 4.51 mm in women to 6.85 mm in men at 3 mm from the midpalatal suture and from 4.29 mm in women to 6.64 mm in men at 6 mm for 90°. In the posterior region, the bone thickness varied from 2.93 mm (3 mm from the suture) to 1.78 mm (6 mm from the suture) for women and from 3.24 mm (3 mm from the suture) to 1.99 mm (6 mm from the suture) for men. In general, the bone thickness of the palate is greater in the anterior region at 3 mm from the midpalatal suture at 30°. CONCLUSIONS: There was high variability in the bone thickness of the palate among patients and in different areas. Therefore, it is necessary to make an individualized diagnosis of the patient and manufacture the MARPE appliance carefully by performing a prior evaluation of the palatal bone thickness by means of CBCT to determine the ideal sites and inclinations for placement of mini-implants.

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

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

Evaluation of factors related to the success of miniscrew-assisted rapid palatal expansion.

OBJECTIVES: To evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as midpalatal suture (MPS) maturation, age, sex, or bicortical mini-implant anchorage. MATERIALS AND METHODS: Twenty-eight cone beam computed tomography (CBCT) scans of adults and post-pubertal adolescents treated by MARPE were included in the sample. CBCT images before (T0) and after expansion (T1) were used to evaluate the skeletal changes and the success or failure of MARPE. Axial images of MPS were extracted from T0 and classified into one of the five maturation stages. The correlation between MARPE success and the factors of age, sex, MPS maturation, and bicortical mini-implant anchorage was investigated. RESULTS: Only the age showed a statistically significant negative correlation with MARPE success and all the skeletal measures. There was an 83.3% success rate among individuals aged 15 to 19 years, 81.8% from 20 to 29 years, and 20% from 30 to 37 years. MPS maturation showed a negative correlation with the expansion effect. Subjects with stages B or C of MPS maturation showed a 100% success rate, followed by stage D (62.5%) and stage E (58.3%). CONCLUSIONS: As age increased, there was a decrease in MARPE success and the skeletal effects of maxillary expansion. Sex and bicortical mini-implant anchorage were not shown to be relevant factors. There was no correlation between MPS maturation and MARPE success; however, it was observed that all cases of MARPE failure were classified as stage D or E of MPS maturation.

Genotoxicity and cytotoxicity induced by eluates from orthodontic glass ionomer cements in vitro.

The aim of this study was to investigate genotoxicity and cytotoxicity of some orthodontic glass ionomer cements commercially available by means of the single cell gel (comet) assay. For this purpose, five commercial orthodontic glass ionomer cements (Vidrion C®, Meron®, Optiband®, Multicure® and Ultra Band Lok®) were tested in murine fibroblasts in vitro. For this purpose, eluates from each cement were prepared according manufactures instructions at 0, 2, 4, 8, 18, 32 and 64 days of immersion in artificial saliva at 37 °C. All orthodontic glass ionomer cements failed to induce cytotoxicity to murine fibroblasts for all periods evaluated in this study. However, Vidrion C® was able to induce genotoxicity after 64 days of exposure to eluates. Meron® also demonstrated genotoxicity as depicted by increasing DNA damage on 2nd day. Multicure® demonstrated genotoxicity on 32nd day and Ultra band Lok on 18th, 32nd days of exposure. Taken together, our results demonstrated that orthodontic cements derived from resin-modified glass ionomer composite (Multicure®) and compomer (Ultra Band Lok®) cause genetic damage in mammalian cells in vitro.

Do Dental X-Rays Induce Genotoxicity and Cytotoxicity in Oral Mucosa Cells? A Critical Review.

Dental X-rays are widely used in clinical practice, since the technique is an important approach for diagnosing diseases in dental and periodontal tissues. However, it is widely known that radiation is capable of causing damage to cellular systems, such as genotoxicity or cytotoxicity. Thus, the aim of this review was to present a critical analysis regarding the studies published on genotoxicity and cytotoxicity induced by dental X-rays in oral mucosa cells. Such studies have revealed that some oral cell types are more sensitive than others following exposure to dental X-rays. Certainly, this review will contribute to a better understanding of this matter as well as to highlighting perspectives for further studies. Ultimately, such data will promote better safety for both patients and dental professionals.

The construction of arteriovenous fistula for hemodialysis in patients with chronic obstructive arterial disease in the upper limb.

OBJECTIVE: Describe the construction of arteriovenous fistula for hemodialysis in chronic renal patient on hemodialysis who presented chronic arterial obstruction in the upper limb. METHODS: A surgical procedure was performed on a patient with obstruction of the brachial artery in its proximal third. The procedure was carried out by the construction of a bypass with autologous vein between the proximal brachial and distal brachial arteries and the performing of an arteriovenous fistula with superficialized and anteriorized basilic vein, with anastomosis in the bypass at the same surgical procedure. RESULTS: There was good immediate result and arteriovenous fistula presented function for 43 months. CONCLUSIONS: Even when faced with chronic obstructive arterial disease in the arm, there is the possibility of creating a new arteriovenous fistula for hemodialysis.

Prediction of rapid maxillary expansion by assessing the maturation of the midpalatal suture on cone beam CT

ABSTRACT Rapid maxillary expansion (RME) primarily involves the mechanical opening of the midpalatal suture of the maxillary and palatine bones. The fusion of the midpalatal suture determines the failure of RME, a common event in late adolescents and young adults. Recently, the assessment of the maturation of midpalatal suture as viewed using cone beam computed tomography (CBCT) has been introduced. Five maturational stages of the midpalatal suture have been presented: Stage A = straight high-density sutural line, with no or little interdigitation; Stage B = scalloped appearance of the high-density sutural line; Stage C = two parallel, scalloped, high-density lines that lie close to each other, separated in some areas by small low-density spaces; Stage D = fusion of the palatine bone where no evidence of a suture is present; and Stage E = complete fusion that extends also anteriorly in the maxilla. At Stage C, less skeletal response would be expected than at Stages A and B, as there are many bony bridges along the suture. For patients at Stages D and E, surgically assisted RME would be necessary, as the fusion of the midpalatal suture already has occurred either partially or totally. This diagnostic method can be used to estimate the prognosis of the RME, mainly for late adolescents and young adults for whom this procedure is unpredictable clinically.

RESUMO A expansão rápida da maxila (ERM) essencialmente consiste na abertura mecânica da sutura palatina mediana tanto nos ossos maxilares quanto nos ossos palatinos. A fusão da sutura palatina mediana determina o insucesso da ERM, um evento comum na adolescência tardia e fase adulta jovem. Recentemente, propôs-se a avaliação da maturação da sutura palatina mediana em tomografias computadorizadas de feixe cônico (TCFC), sendo apresentados cinco estágios maturacionais: Estágio A = linha sutural de alta densidade retilínea, sem ou com suave interdigitação; Estágio B = linha sutural de alta densidade, com aspecto tortuoso; Estágio C = duas linhas de alta densidade, paralelas e curvilíneas, que se aproximam em algumas regiões e, em outras, são separadas por espaços de baixa densidade; Estágio D = a fusão ocorreu no osso palatino, onde não há evidência de sutura; e Estágio E = fusão completa, que se estende anteriormente na maxila. No Estágio C, esperam-se menores efeitos esqueléticos da ERM, comparado aos Estágios A e B, visto que há muitas pontes ósseas ao longo da sutura. Para pacientes nos Estágios D e E, a expansão rápida da maxila assistida cirurgicamente (ERMAC) seria necessária, já que a fusão da sutura palatina mediana ocorreu parcial ou totalmente. Esse método de diagnóstico pode ser utilizado para estimar o prognóstico da ERM, principalmente na adolescência tardia e fase adulta jovem, período em que esse procedimento ainda apresenta-se imprevisível clinicamente.

Aglossia: Case Report

Introduction Aglossia is a rare condition caused by failure of the tongue embryogenesis process (in the fourth to eighth weeks of gestation). The tongue is an organ used in different activities such as sucking, swallowing, chewing, and talking. It is also responsible for shaping palate dental arches (in its absence, they become atrophic). There are few similar cases reported in the literature. Objective To describe a rare case of aglossia and the multidisciplinary professionals working together for 5 years to treat the patient. Resumed Report An 8-year-old girl with aglossia had an assessment comprising: (1) clinical assessment of the stomatognathic system related to resting posture, tonus, and mobility; (2) orthodontic assessment; (3) surface electromyography of the chewing muscles; (4) swallowing videofluoroscopy. Conclusion The authors confirmed the need of multidisciplinary cooperation to improve the patient s quality of life, because agenesia implicates many activities/ functions that depend on the tongue to fully work. Multiprofessional cooperation helps the patient learn compensation mechanisms.

Aglossia: Case Report.

Introduction Aglossia is a rare condition caused by failure of the tongue embryogenesis process (in the fourth to eighth weeks of gestation). The tongue is an organ used in different activities such as sucking, swallowing, chewing, and talking. It is also responsible for shaping palate dental arches (in its absence, they become atrophic). There are few similar cases reported in the literature. Objective To describe a rare case of aglossia and the multidisciplinary professionals working together for 5 years to treat the patient. Resumed Report An 8-year-old girl with aglossia had an assessment comprising: (1) clinical assessment of the stomatognathic system related to resting posture, tonus, and mobility; (2) orthodontic assessment; (3) surface electromyography of the chewing muscles; (4) swallowing videofluoroscopy. Conclusion The authors confirmed the need of multidisciplinary cooperation to improve the patient's quality of life, because agenesia implicates many activities/functions that depend on the tongue to fully work. Multiprofessional cooperation helps the patient learn compensation mechanisms.

Prediction of rapid maxillary expansion by assessing the maturation of the midpalatal suture on cone beam CT.

Rapid maxillary expansion (RME) primarily involves the mechanical opening of the midpalatal suture of the maxillary and palatine bones. The fusion of the midpalatal suture determines the failure of RME, a common event in late adolescents and young adults. Recently, the assessment of the maturation of midpalatal suture as viewed using cone beam computed tomography (CBCT) has been introduced. Five maturational stages of the midpalatal suture have been presented: Stage A = straight high-density sutural line, with no or little interdigitation; Stage B = scalloped appearance of the high-density sutural line; Stage C = two parallel, scalloped, high-density lines that lie close to each other, separated in some areas by small low-density spaces; Stage D = fusion of the palatine bone where no evidence of a suture is present; and Stage E = complete fusion that extends also anteriorly in the maxilla. At Stage C, less skeletal response would be expected than at Stages A and B, as there are many bony bridges along the suture. For patients at Stages D and E, surgically assisted RME would be necessary, as the fusion of the midpalatal suture already has occurred either partially or totally. This diagnostic method can be used to estimate the prognosis of the RME, mainly for late adolescents and young adults for whom this procedure is unpredictable clinically.

Diagnostic performance of skeletal maturity for the assessment of midpalatal suture maturation.

INTRODUCTION: The aim of this study was to analyze the diagnostic performance of the cervical vertebral maturation (CVM) method in estimating accurately the stages of maturation of the midpalatal suture. METHODS: Cone-beam computed tomography (CBCT) images from 142 subjects (84 female, 58 male; mean age, 14.8 ± 9.7 years) were analyzed by 2 calibrated examiners to define, by visual analysis, the maturational stages of the cervical vertebrae and the midpalatal suture. These CBCT images were required by orthodontists and surgeons for diagnosis and treatment purposes. Positive likelihood ratios (LHRs) were calculated to evaluate the diagnostic performance of the CVM stages in identifying the maturational stages of the midpalatal suture. RESULTS: Positive LHRs greater than 10 were found for several cervical vertebral stages (CSs), including CS1 and CS2 for the identification of midpalatal suture stages A and B, CS3 for the diagnosis of midpalatal suture stage C, and CS5 for the assessment of midpalatal suture stages D and E. These positive LHRs indicated large and often conclusive increases in the likelihood that the CVM stages were associated with specific stages of midpalatal suture maturation. At CS4, there were a moderate positive LHR for stage C and low positive LHRs for stages D and E. CONCLUSIONS: Most CVM stages can be used for the diagnosis of the stages of maturation of the midpalatal suture, so that CBCT imaging may not be necessary in these patients. In the postpubertal period, however, an assessment of the midpalatal suture maturation using CBCT images may be indicated in deciding between conventional rapid maxillary expansion and surgically assisted rapid maxillary expansion. On the other hand, if the CVM stage cannot be assessed, chronologic age may be a viable alternative to predict some midpalatal suture stages (particularly the early stages).

Pseudoaneurisma da artéria poplítea em um paciente com Síndrome de Ehlers-Danlos Tipo VI / Pseudoaneurysm of the popliteal artery in a patient with Type VI Ehlers-Danlos Syndrome

A Síndrome de Ehlers-Danlos (EDS) é uma rara doença hereditária do tecido conjuntivo proveniente de uma alteração da síntese do colágeno. A principal característica da EDS é a extrema fragilidade do tecido conjuntivo, que pode resultar em rotura uterina, perfuração intestinal espontânea e várias doenças vasculares como aneurismas, pseudoaneurismas, dissecções arteriais e roturas espontâneas. Os autores relatam o caso de um paciente de 11 anos de idade que apresentava tumor pulsátil na fossa poplítea esquerda após trauma leve com bola de futebol. Diagnosticado pseudoaneurisma de artéria poplítea pelo doppler arterial, confirmado através da angiografia, optou-se pela exploração arterial e devido à fragilidade da parede não foi possível a sua reconstrução. Realizada a ligadura simples da artéria proximal. Evoluiu com isquemia grave do membro e após autorização da família foi realizada a sua amputação. No segundo dia do pós-operatório o paciente apresentou uma dissecção aguda da aorta torácica, evoluindo a óbito.

Ehlers-Danlos Syndrome (EDS) is a rare inherited connective tissue disease arising from an abnormality of collagen synthesis. The main feature of EDS is the extreme fragility of connective tissues, which can result in uterine rupture, spontaneous intestinal drilling and vascular diseases such as aneurysms, pseudoaneurysms, arterial dissections and spontaneous ruptures. This paper describes the case of an 11-year-old patient who presented a pulsatile mass in the left popliteal fossa after a minor trauma caused by a soccer ball. A pseudoaneurysm of the popliteal artery was diagnosed with arterial Doppler ultrasound and confirmed using angiography. An exploratory investigation revealed that the artery wall was too weak to allow reconstruction and the proximal artery was ligated. The patient developed severe limb ischemia and after authorization by the family the limb was amputated. Two days after surgery, the patient died as a result of acute thoracic aortic dissection.

The role of rapid maxillary expansion in the promotion of oral and general health.

Rapid maxillary expansion (RME) is an effective orthopedic procedure that can be used to address problems concerned with the growth of the midface. This procedure also may produce positive side effects on the general health of the patient. The aim of the present consensus paper was to identify and evaluate studies on the changes in airway dimensions and muscular function produced by RME in growing patients. A total of 331 references were retrieved from a database search (PubMed). The widening of the nasal cavity base after midpalatal suture opening in growing patients allows the reduction in nasal airway resistance with an improvement of the respiratory pattern. The effects of RME on the upper airway, however, have been described as limited and local, and these effects become diminished farther down the airway, possibly as a result of soft-tissue adaptation. Moreover, limited information is available about the long-term stability of the airway changes produced by RME. Several studies have shown that maxillary constriction may play a role in the etiology of more severe breathing disorders such as obstructive sleep apnea (OSA) in growing subjects. Early orthodontic treatment with RME is able to reduce the symptoms of OSA and improve polysomnographic variables. Finally, early orthopedic treatment with RME also is beneficial to avoid the development of facial skeletal asymmetry resulting from functional crossbites that otherwise may lead to functional and structural disorders of the stomatognathic system later in life.

Long-term treatment effects of the FR-2 appliance: a prospective evalution 7 years post-treatment.

AIM: To examine the long-term effects induced by treatment with the function regulator (FR-2) appliance 7 years post-treatment compared with untreated class II subjects. SUBJECTS AND METHODS: The FR-2 sample was collected prospectively and comprised 17 subjects (10 boys and 7 girls, mean age 10.8 years) who were treated with the FR-2 appliance for 1.7 years and re-evaluated 7.1 years after treatment. The step-by-step mandibular advancement was performed gradually (increments up to 3-4 mm), until a 'super class I' molar relationship was obtained. The control group consisted of 17 class II subjects (9 boys and 8 girls, mean age 11.3 years) with class II malocclusion, excessive overjet, and class II molar relationship, matched to the treated group as to ages at all times, gender distribution, and stages of skeletal maturity (evaluated by the cervical vertebral maturation method). The lateral cephalograms were analysed at T1 (initial), T2 (final), and T3 (7.1 years post-treatment). The compatibility between the groups and the comparisons of their changes at T1-T2, T2-T3, and T1-T3 intervals were examined by independent sample t-tests (P < 0.05). RESULTS: FR-2 treatment provided a significant improvement in the maxillomandibular relationship due to an increase in mandibular length compared with controls, which remained stable over time. Also overjet, overbite, and molar relationship corrections demonstrated stability. Among dentoalveolar changes, only the increased mesial movement of the mandibular molars in the FR-2 group demonstrated stability. CONCLUSIONS: Correction of class II malocclusion remained stable 7 years after FR-2 treatment mainly due to the stability of the skeletal changes.

Midpalatal suture maturation: classification method for individual assessment before rapid maxillary expansion.

INTRODUCTION: In this study, we present a novel classification method for individual assessment of midpalatal suture morphology. METHODS: Cone-beam computed tomography images from 140 subjects (ages, 5.6-58.4 years) were examined to define the radiographic stages of midpalatal suture maturation. Five stages of maturation of the midpalatal suture were identified and defined: stage A, straight high-density sutural line, with no or little interdigitation; stage B, scalloped appearance of the high-density sutural line; stage C, 2 parallel, scalloped, high-density lines that were close to each other, separated in some areas by small low-density spaces; stage D, fusion completed in the palatine bone, with no evidence of a suture; and stage E, fusion anteriorly in the maxilla. Intraexaminer and interexaminer agreements were evaluated by weighted kappa tests. RESULTS: Stages A and B typically were observed up to 13 years of age, whereas stage C was noted primarily from 11 to 17 years but occasionally in younger and older age groups. Fusion of the palatine (stage D) and maxillary (stage E) regions of the midpalatal suture was completed after 11 years only in girls. From 14 to 17 years, 3 of 13 (23%) boys showed fusion only in the palatine bone (stage D). CONCLUSIONS: This new classification method has the potential to avoid the side effects of rapid maxillary expansion failure or unnecessary surgically assisted rapid maxillary expansion for late adolescents and young adults.

Stability evaluation of occlusal changes obtained with Fränkel's Function Regulator-2

OBJECTIVE: To analyze the stability of occlusal changes promoted by the Frankel's Functional Regulator 2 (FR-2), in a mean period of 7.16 years post treatment. METHODS: Fifty-four pairs of models were evaluated, from 18 patients treated with FR-2. All patients had Class II, division 1 malocclusion, with initial mean age of 10.77 years and were treated with FR-2 for 18 months. The models were evaluated at the beginning of treatment (T1), at the end (T2) and after 7.16 years post treatment (T3). For occlusal evaluation, the treatment priority index (TPI) was applied on the three analyzed phases. The alterations that occurred between phases were verified with one another through paired Student's t test, with critical value of 0.05. RESULTS: A statistically significant reduction of TPI was verified, from the initial to the final phase of the treatment, reflecting the efficiency of treatment performed with FR-2, specially due to improvement in molar relation, overjet and overbite. Apart from this, the Class II correction remained stable over time. CONCLUSIONS: In this way, it is concluded that the FR-2 appliance showed to be efficient for the dental correction of Class II malocclusion, with stable occlusal results after 7.16 years post treatment.

OBJETIVO: analisar a estabilidade das alterações oclusais promovidas pelo aparelho Regulador de Função Fränkel-2 (RF-2), num período médio de 7,16 anos pós-tratamento. MÉTODOS: foram avaliados 54 pares de modelos, provenientes de 18 pacientes tratados por meio do aparelho RF-2. Todos os pacientes possuíam má oclusão de Classe II, divisão 1, com idade inicial média de 10,77 anos e foram tratados com o RF-2 por 18 meses. Os modelos foram avaliados no início do tratamento (T1), no final do tratamento (T2) e decorridos 7,16 anos pós-tratamento ativo (T3). Para a avaliação oclusal, aplicou-se o Índice de Prioridade de Tratamento (IPT) nas três fases analisadas. As alterações ocorridas entre as fases foram verificadas entre si por meio do teste t de Student pareado, com o valor crítico adotado de 0,05. RESULTADOS: verificou-se uma diminuição estatisticamente significativa do IPT, da fase inicial à final de tratamento, refletindo a eficácia do tratamento realizado por meio do RF-2, principalmente devido à melhora da relação molar, do trespasse horizontal e vertical. Além disso, a correção da má oclusão de Classe II obtida permaneceu estável no decorrer do tempo. CONCLUSÃO: concluiu-se que o aparelho RF-2 demonstrou ser eficaz na correção dentária da má oclusão de Classe II, com resultados oclusais estáveis decorridos 7,16 anos pós-tratamento.