Comparative assessment of two-phase class II treatment with Activator or Bionator followed by fixed appliances: A retrospective controlled before-and-after study.

AIM: Two-phase treatment for children with Class II malocclusion with several functional appliances is still performed by many orthodontists, while the Activator and the Bionator appliances are two of the most popular ones. Aim of this study was to compare the skeletal and dentoalveolar effects of treatment with these two appliances. METHODS: Class II children treated with Activator or Bionator in the first phase, followed by a phase of fixed appliances were included. Skeletal and dentoalveolar parameters were assessed from lateral cephalograms and analysed with linear regressions at 5%. RESULTS: A total of 89 patients (mean age 10.0 years; 47% female) were included. During the first phase, Bionator increased less the SNB (difference in mean treatment-induced changes [MD] -0.7°; 95% confidence interval [CI] -1.3 to -0.2°; P=0.01) and decreased less the ANB angle (MD 0.6°; 95% CI 0 to 1.1°; P=0.03) compared to Activator. Activator slightly increased the facial axis and Bionator reduced it (MD -1.6°; 95% CI -2.3 to -0.8°; P<0.001). Compared to Activator, the Bionator retroclined more the upper incisors (MD -2.4°; 95% CI -4.6 to -0.2°; P=0.03) and increased more the interincisal angle (MD 2.9°; 95% CI 0.5 to 5.4°; P=0.02). After the second phase (6.2 years after baseline), the only differences were a reduced facial axis (MD -1.3°; 95% CI -2.2 to -0.3°; P=0.008) and an increased maxillary rotation (MD 0.9°; 95% CI 0 to 1.8°; P=0.04) with Bionator compared to Activator. CONCLUSION: Similar dentoalveolar effects were seen overall with two-phase treatment with either appliance, with Bionator being associated with more vertical increase compared to Activator.

3D assessment of mandibular skeletal effects produced by the Herbst appliance.

BACKGROUND: A functional appliance is commonly used to optimize the development of the facial skeleton in the treatment of Class II malocclusion. Recent three-dimensional(3D) image-based analysis offers numerous advantages in quantitative measurement and visualization in orthodontics. The aim of this study was to localize in 3D the skeletal effect produced by the Herbst appliance on the mandible using the geometric morphometric technique. METHODS: Twenty patients treated with a Herbst appliance and subsequent fixed appliances were included. Cone-beam computed tomography (CBCT) images were taken before treatment (T1), 8 weeks after Herbst appliance removal (T2), and after subsequent fixed appliance treatment (T3). Spatially dense morphometric techniques were used to establish the corresponding points of the mandible. The mandibular morphological changes from T1-T2, T2-T3, and T1-T3 were calculated for each patient by superimposing two mandibular models at two time points with robust Procrustes superimposition. These changes were then compared to the morphological changes estimated from normative mandibular growth curves over the same period. The proportion of cases exceeding the growth expression for controls was compared to a normal population using a one tailed binomial test. RESULTS: Approximately 1.5-2 mm greater condylar changes and 0.5 mm greater changes in the chin occurred from Tl to T2. This effect lasted until the completion of treatment (T1-T3), but there was no obvious skeletal effect during the orthodontic phase (T2-T3). Approximately 40-50% of the patient sample exceeded condylar growth by > 1.5 mm compared to untreated controls (p < .05). However, changes at the chin were not statistically significant. CONCLUSIONS: The principal skeletal effect of Herbst appliance treatment was additional increase in condylar length for about half of the sample. This inconsistency may relate to the degree of mandibular growth suppression associated with a specific malocclusion.

Nonsurgical treatment of Brodie bite assisted by 3-dimensional planning and assessment.

This case report describes the nonsurgical treatment of an adolescent patient with a severe transverse discrepancy presented as a Brodie bite and retrognathic mandible. Distraction osteogenesis has been often used for similar cases in the literature. However, in this patient, a fixed appliance with 1 maxillary extraction combined with a functional appliance was used to resolve the transverse discrepancy with natural growth. After the orthodontic treatment, the impinging teeth and Brodie bite were corrected with a favorable occlusion and profile. Retention at the 3-year follow-up showed improved occlusal interdigitation and good stability.

Three-dimensional assessment of the middle cranial fossa and central skull base following Herbst appliance treatment.

OBJECTIVES:: The purpose of this three-dimensional (3D) study was to assess retrospectively the middle cranial fossa and central skull base of patients treated with the Herbst appliance (HA). MATERIALS AND METHODS:: 3D surface virtual models of 40 Class II, division 1 malocclusion patients were generated from cone-beam computed tomography (CBCT) acquired before treatment (T0) and after 8 months of HA treatment (T1). T0 and T1 3D models were superimposed volumetrically at the anterior cranial fossa. Twenty subjects who had been treated with the Herbst appliance (HAG) were compared to 20 subjects who were not treated orthopedically. The latter group served as a comparison control group (CG). Quantitative assessments of the location and directional changes were made with linear and angular measurements between anatomical landmarks. Qualitative assessments of the spatial behavior of the middle cranial fossa and central skull base relative to the anterior cranial fossa were displayed graphically for visualization with color maps and semitransparent overlays. Non-parametric tests were performed to compare the between the HAG and CG. RESULTS:: Point-to-point linear measurements and skeletal rotation (pitch, roll, and yaw) changes were very small along the observational period and were not significantly different between HAG and CG. Visual analysis of color maps and overlays confirmed that no changes in the cranial base were associated with HA. CONCLUSIONS:: HA therapy did not produce clinically significant changes in the middle cranial fossa and central skull base.

A cost-minimization analysis of large overjet reduction with two removable functional appliances based on a randomized controlled trial.

Objective: The purpose of this study was to assess and relate the societal costs of reducing large overjet with a prefabricated functional appliance (PFA), or a slightly modified Andresen activator (AA), using a cost-minimization analysis (CMA). Design, settings, and participants: A multicentre, prospective, randomized clinical trial was conducted with patients from 12 general dental practices. Ninety-seven patients with an Angle Class II, division 1 malocclusion, and an overjet of ≥6 mm were randomly allocated by lottery to treatment with either a PFA or an AA. The PFA and AA groups consisted of 57 and 40 subjects, respectively. Blinding was not performed. Duration of treatment, number of scheduled/unscheduled appointments, and retreatment were registered. Direct and indirect costs were analysed with reference to intention-to-treat (ITT), successful (S), and unsuccessful (US) outcomes. Societal costs were described as the total of direct and indirect costs, not including retreatments. Interventions: Treatment with a PFA or an AA. Results: The direct and societal costs were significantly lower for the PFA than for the AA group. The number of visits was lower in the PFA group, when ITT was considered, and for the US cases as well. No difference in retreatment rate could be seen between the groups. Limitations: Costs depend on local factors and thus should not be generalized to other settings. Harms: No harms were detected during the study. Conclusion: The success rate of the both appliances was low. However, the PFA was the preferred approach for reduction of a large overjet in mixed dentition, since it minimized costs and there were no difference in clinical outcomes between PFA and AA. Registration: This trial was registered at 'FoU i Sverige' (http://www.fou.nu/is/sverige), registration number: 97131. Protocol: The protocol was not published before trial commencement.

Dental skeletal effects of the metallic splinted Herbst appliance after growth spurt: a lateral oblique cephalometric assessment.

The aim of this study was to evaluate dental and skeletal changes induced by the use of Herbst appliance compared to natural growth in young adults with Class II division I malocclusion with mandibular retrusion, by means of lateral oblique radiographs. Forty-six subjects, I4 -18 years old, after pubertal growth peak, with Class II division I malocclusion were assessed. Subjects were divided into two groups: the Experimental group included 23 subjects treated with Metallic Splinted Herbst and the Control group included 23 subjects followed without treatment. The Experimental and Control groups were paired by sex and chronological age. Oblique lateral cephalometric radiographs of the left and the right side of the mandible before treatment (TI) and after 8 months' treatment (T2) were used to evaluate dental and skeletal changes. Statistical analysis was performed with Intra Class Correlation and Student t-test, according to the study hypothesis. The results showed that the appliance corrected the Class II relationship in an 8-month period by mesial tipping movement of lower permanent first molars. It had little influence on mandibular structure and mandibular length and no influence on maxillary structure and upper molar. To conclude, late treatment of Class II malocclusion with the Herbst appliance was accomplished by means of dentoalveolar changes. These findings suggest that this type of treatment can be used in patients after growth has ceased because the results do not depend upon skeletal changes.

O objetivo é avaliar mudanzas dento esqueléticas induzidas pelo uso do aparelho de Herbst considerando crescimento natural através da telerradiografía cefalométrica em 45o em adultos jovens com Classe II divisao 1 e retrusao mandibular. Uma amostra de 46 individuos com idade entre 14 a 18 anos, após surto de crescimentopubertário, Classe II divisao 1 foram avaliados e divididos em dois grupos: grupo Experimental, 23 individuos que foram tratados com Herbst splint metálico e grupo Controle, 23 individuos que foram acompanhados sem tratamento. Os grupos experimental e Controle foram pareados por genero e idade cronológica. Foram usadas telerradiografias cefalométrica em 45o dos lados esquerdo e direito da mandíbula antes do tratamento (T1) e após periodo de 8 meses de tratamento e seguinte (T2) para avaliar as mudanzas dento esqueléticas. Análise estatistica foi realizada com o indice de Correlagao Intra Classe e teste t de Student de acordo com a hipótese do estudo. Os resultados mostraram que houve corregaoda relagao de Classe II no periodo de 8 meses por movimento mesial do primeiro molar inferior. O aparelho teve pequena influencia na estrutura mandibular e compri-mento mandibular e nenhuma influencia na estrutura maxilar e molar superior. Em conclusao, o tratamento tardio da má-oclusao de Classe II com o aparelho MESPHER foi alcangado através de mudangas dento alveolares.

Objective assessment of compliance with intra- and extraoral removable appliances.

OBJECTIVE: To conduct an objective assessment of the level of compliance in young patients prescribed various types of removable appliances and to determine the influence of device type, treatment duration, and patient age, gender, psychological maturity, and awareness of monitoring on compliance. MATERIALS AND METHODS: A total of 30 patients were fitted with either a class 2 (Frankel or bionator) or a class 3 (face mask) removable appliance, each bearing a compliance indicator chip, and they were instructed to wear them for 13 hours per day. Compliance was monitored by means of the sensor for an average of 8 months. Of the patients, 14 were informed that their appliance was fitted with a monitoring sensor, and 16 were not. The psychological maturity of all patients was assessed on the Nowicki-Strickland Locus of Control Scale, and the effect on compliance of this score as well as the patient- and treatment-related variables considered were determined via statistical analysis Results: The mean compliance recorded by the chips was 8.6 ± 2.9 hours, far lower than the 13 hours prescribed, and younger patients showed significantly greater compliance than adolescents (P < .01). However, no significant differences in compliance were found between intra- and extraoral appliances, and neither gender, psychological scores, treatment duration, nor awareness of being monitored had any significant effect. CONCLUSIONS: Compliance is generally very poor in young patients, regardless of their gender and psychological maturity. Although awareness of monitoring does not appear to boost compliance, such systems may be a valuable means of providing a dentist with objective information regarding their patients' compliance.

Mapeamento tridimensional das alterações dentoesqueléticas mandibulares decorrentes do tratamento com os aparelhos de Herbst e Twin Block / Three-dimensional assessment of dentoskeletal mandibular changes resulting from treatment with Herbst and Twin Block appliances

Este estudo teve como objetivo avaliar tridimensionalmente as alterações dentoesqueléticas mandibulares observadas em pacientes Classe II esqueléticos em crescimento tratados com os aparelhos de Twin Block e Herbst. Foram selecionados 22 adolescentes brasileiros, de ambos os gêneros, portadores de má oclusão de Classe II de Angle, 1a divisão, no pico do surto de crescimento puberal (estágio de maturação das vértebras cervicais CS3-CS4). Todos os pacientes foram tratados durante 12 meses na Clínica de Especialização em Ortodontia da Faculdade de Odontologia da Universidade do Estado do Rio de Janeiro (FOUERJ). O grupo Twin Block (TB) foi composto por 15 pacientes (9 meninos e 6 meninas; médias de idade de 12,3 e 11,9 anos, respectivamente) tratados com o aparelho funcional removível de Twin Block. O grupo Herbst (HB) foi constituído por 7 pacientes (4 do gênero masculino e 3 do feminino com médias de idade de 13,6 e 12,3 anos, respectivamente) submetidos a tratamento com o aparelho propulsor mandibular de Herbst multi-bandado, cimentado às coroas de caninos, pré-molares e molares permanentes. Foram obtidas tomografias computadorizadas de feixe cônico (TCFC) de todos os pacientes em duas etapas: imediatamente antes do início do tratamento (T1) e após 12 meses de tratamento (T2). Foram construídos 44 modelos virtuais 3D das mandíbulas de todos os indivíduos nos dois tempos avaliados. Foi realizada a superposição dos modelos de T1 e T2 para avaliar as seguintes regiões anatômicas de interesse (RAI): côndilo, ramo e corpo mandibular e incisivos centrais inferiores. As maiores distâncias em milímetros aferidas para cada RAI entre T1 e T2 foram registradas e comparadas posteriormente pelo teste Mann-Whitney. O teste de Wilcoxon foi utilizado para comparar as RAIs em pares. Os resultados mostraram que ambos os aparelhos produziram maiores efeitos esqueléticos do que dentários e não foram encontradas diferenças significantes entre os grupos em nenhuma das medidas avaliadas (p < 0,05). Ambos os grupos apresentaram em média, um crescimento mais acentuado na região condilar (côndilo direito = 6,12 mm no grupo TB e 7,01 mm no grupo HB; côndilo esquerdo = 6,34 mm no grupo TB e 6,84 mm no grupo HB); pouco crescimento na região do ramo mandibular (ramo direito = 1,80 mm no grupo TB e 1,65 mm no grupo HB; ramo esquerdo = 1,86 mm no grupo TB e 1,66 mm no grupo HB); o corpo mandibular foi a região que apresentou menor crescimento (0,54 mm tanto no grupo TB quanto no grupo HB). Foi observada uma inclinação vestibular dos incisivos inferiores similar em ambos os grupos (dente 31 = 1,37 mm no grupo TB e 1,67 mm no grupo HB; dente 41 = 1,34 mm no grupo TB e 1,53 mm no grupo HB). Concluiu-se que os pacientes tratados com os aparelhos de Twin Block e Herbst apresentaram resultados similares no crescimento mandibular e na projeção dos incisivos inferiores.

The present study aimed to assess the three-dimensional dentoskeletal mandibular changes in skeletal Class II growing patients treated with Twin Block and Herbst appliances. The sample was comprised by 22 Brazilian adolescents, both genders, malocclusion Class II division 1, at the peak of the pubertal growth spurt (CS3-CS4 stages of cervical vertebrae maturation). All patients were treated for 12 months at the Orthodontic Clinic, School of Dentistry, State University of Rio de Janeiro (FOUERJ). Twin Block group (TB) was composed of 15 patients (9 boys and 6 girls with mean ages of 12.3 and 11.9 years, respectively) treated with the Twin Block removable appliance. The Herbst group (HB) was formed by 7 youths (4 males and 3 females with mean ages 13.6 and 12.3 years, respectively) treated with the banded Herbst functional appliance, bonded to canines, premolars and molars. Cone Beam Computed Tomography (CBCT) were obtained for each patient in two time points: immediately before the start of the treatment (T1) and after 12 months of treatment (T2). Forty-four virtual 3D mandible models were built from the CBCTs for the whole sample. Superimpositions were made between T1 and T2 to evaluate the following specific regions of interest (SRI): condyles, mandibular ramus and corpus and lower central incisors. The greater distances in millimeters measured for each SRI between T1 and T2 were recorded and then compared using the Mann-Whitney test. The Wilcoxon test was used to compare the SRIs in pairs. Results showed both funcional appliances produced more esqueletal than dental effects. There were no differences between the groups for all regions analized (p < 0.05). Both groups presented in average, the most pronounced growth in condylar areas (right condyle = 6.12 mm in group TB and 7.01 mm in group HB; left condyle = 6.34 mm in group TB and 6.84 mm in group HB); small growth of the mandibular ramus (right ramus = 1.80 mm in group TB and 1.65 mm in group HB; left ramus = 1.86 mm in group TB and 1.66 mm in group HB); and the mandibular corpus showed the minor growth (0.54 mm both in groups TB and HB). The lower incisors presented a similar proclination in both groups (teeth 31 = 1.37 mm in group TB and 1.67 mm in group HB; teeth 41 = 1.34 mm in group TB and 1.5 mm in group HB). It can be concluded that patients treated with the Twin Block and Herbst appliances presented similar results concerning mandibular growth and lower incisor proclination.

Adolescents' experiences of using removable functional appliances.

OBJECTIVES: The aim of this qualitative study was to explore and describe adolescents' experiences of treatment with removable functional appliances. SETTING AND SAMPLE POPULATION: Public Dental Service, Gothenburg, Sweden. MATERIAL AND METHODS: Individual interviews focusing on adolescents' experiences of using a removable functional appliance were held with 21 adolescents (12 girls and nine boys). The mean age of the participants was 13.2 years (range 11-15, SD 1.25) at the interview occasion. Interviews were transcribed verbatim and analysed according to a qualitative research approach, phenomenography. RESULTS: Outcomes of data analysis emerged in five categories with totally 12 subcategories that describe the adolescents' various conceptions of the treatment. The adolescent's experiences of using removable functional appliance appeared to have a large variation, comprising of the individual approach, feelings and strategies, the dentist role and receiving external support. CONCLUSION: Participants developed their own strategies of measurement to see improvement. An active involvement of the adolescents' in the treatment seems to be needed, supported by the dentist at coming appointments, using overjet measurement as a tool for motivation. Furthermore, efforts should be made by clinicians to listen and understand adolescents' needs and requirement before the treatment start.

An assessment of late fixed functional treatment and the stability of Forsus appliance effects.

OBJECTIVE: To evaluate the treatment effects and stability of Forsus appliance therapy. METHODS: Thirty-one patients (15 males, 16 females) with a mean age of 15.8 +/- 3.1 years (range 13 to 17.6 years, 15.3 +/- 1.2 years for females and 16.5 +/- 1.6 years for males) were selected. All patients had passed beyond their pubertal growth phase (after CS4 or MP3cap). Lateral cephalograms and threedimensional (3D) models were analysed before treatment (T0), at the end of treatment (T1) and at a follow-up visit (T2). The mean period from T1 to T2 was 25 months and ranged from 17 to 32 months. Tooth position and angulations, together with maxillary and mandibular position, were measured on cephalograms. The inclinations and vertical distance changes of mandibular incisors were measured on a 3D digital model. RESULTS: The Forsus appliance produced significant skeletal and dental changes during treatment (from T0 to T1). In the sagittal plane, mandibular length (Co-Gn) increased 6.47 mm, the maxillary incisors and molars uprighted (angle U1-SN decreased 8.97 degrees and angle U6-SN decreased 3.51 degrees), the mandibular incisors proclined (angle L1-MP increased 3.93 degrees) and the mandibular molars advanced (L6-SP increased 3.61 mm). In the vertical plane, the maxilla and mandible rotated clockwise (angle PP-SN, angle MP-SN, angle OP-SN increased significantly) and the mandibular molars extruded (L6-MP increased 3.06 mm). All of the changes remained relatively stable after treatment. Cephalometric sagittal and vertical changes affecting the mandibular incisors from T1 to T2 were statistically insignificant (p > 0.05) except for lower incisor extrusion (L1-MP, p < 0.05). CONCLUSION: The Forsus appliance induced significant skeletal and dental changes, which remained relatively stable during the observation period. The mandibular incisors, in particular, were stable two years after treatment.

Objective assessment of patient compliance with removable orthodontic appliances: a cross-sectional cohort study.

OBJECTIVE: To assess objectively patient compliance with removable orthodontic appliances and the effect of possible influential factors. MATERIALS AND METHODS: Wearing times of 45 White patients were recorded with the aid of the TheraMon microsensor. Patient compliance was assessed relative to wear prescription and other parameters, such as age and sex. RESULTS: There was high individual variation in most measured variables and in all groups/subgroups. During a median observation period of 186 days (range, 55-318 days) the actual wear time was 9.0 h/d (range, 0.0-16.0 h/d) and did not differ between distinct prescriptions (P = .49). Eight patients wore their appliances less than 2 h/d, and six of them did not wear their appliances at all. Overall, the median wear per day relative to prescription was 62.5% (range, 0.0-89.3%) for the 14 h/d and 112.5% (range, 0.0-200.0%) for the 8 h/d prescription wear (P = .01) groups. There was a strong negative correlation of age (median: 12.5 years) with the daily percentage of actual wear time per day relative to wear prescription (14 h/d prescription: n = 21, rho = -0.61, P = .00; 8 h/d prescription: n = 24, rho = -0.73, P = .00), while sex did not exert a significant influence on compliance (P = .58). CONCLUSIONS: Despite the fact that patients and parents were informed about wear time recording, compliance was insufficient with regard to functional treatment (14 h/d prescription), while it was sufficient for retention purposes (8 h/d prescription). Objective measures are necessary to assess compliance with removable orthodontic appliances since patient compliance is a highly variable issue.

Quantification of patient compliance with Hawley retainers and removable functional appliances during the retention phase.

INTRODUCTION: The success of retention with removable retainers is highly dependent on efficient patient compliance. The aim of this study was to quantify patient compliance with removable retainers using microelectronic wear-time documentation during the retention phase. METHODS: One hundred patients, between 13 and 20 years of age, were retained with removable Hawley retainers and functional appliance retainers after successful multibracket treatment at the University Hospital of Tübingen, Germany, and in 4 private practices in Germany. Microsensors were incorporated into the orthodontic retainers by polymerization, and daily wear time was documented in 15-minute intervals during the retention phase for up to 15 months. Patient compliance was quantified with wear-time documentation. Additionally, the influences of age, sex, place of treatment, device type, and health insurance status on compliance were determined and statistically evaluated. RESULTS: Most study participants complied with the prescribed wear time of 8 hours or more per day. Combined patient data indicated a median wear time of 7.0 hours per day over the evaluation period. Wear-time documentation showed either regular or irregular patterns of compliance. Initial compliance did not usually alter over the retention phase. Compliance was not influenced by device type, but age, sex, place of treatment, and insurance status produced changes in the median wear time of up to 50%. CONCLUSIONS: Electronic wear-time documentation of patients' compliance is an easily comprehensible measurement that allows orthodontists to examine the patient's contribution to the success of retention and personalize treatment accordingly. Place of treatment and health insurance status are more closely associated with compliance than are basic patient demographics.

Assessment of pain and discomfort during early orthodontic treatment of skeletal Class III malocclusion using the Removable Mandibular Retractor Appliance.

AIM: To determine the degree of pain and discomfort during the orthodontic treatment of skeletal Class III malocclusion using the Removable Mandibular Retractor (RMR). MATERIALS AND METHODS: The sample consisted of 33 skeletal Class III patients (17 males and 16 females; average age: 7.5 ± 1.33 years) who had been assigned to the RMR treatment group in a randomised controlled trial comparing this treatment versus a control group of no treatment at the Orthodontic Department, University of Al-Baath Dental School in Syria. Pain and discomfort were assessed using standardised questionnaires at the following assessment times: 7 days (T1), 14 days (T2), 6 weeks (T3), 3 months (T4) and 6 months (T5) after appliance insertion. RESULTS: Levels of pain and discomfort decreased gradually by time in general. No significant changes in the levels of pain, tooth sensitivity and soft tissues tension were detected, whereas a significant decrease in the levels of pressure, impaired speech, impaired swallowing and lack of confidence in public was observed two weeks following appliance insertion. Mandibular constraint feeling required three months to decrease significantly. No difference was found between males and females with regard to acceptance. CONCLUSION: The RMR is well accepted by Class III patients in the early mixed dentition.

Guiding atypical facial growth back to normal. Part 2: Causative factors, patient assessment, and treatment planning.

It has been well-documented that the most common factors associated with atypical facial growth involve the airway, which when compromised, leads to mouth breathing and associated aberrant tongue function. The most common changes include downward and backward rotation of the mandible, deficient nasomaxillary complex, a vertical growth pattern, posterior displacement of the TMJ, narrow maxillary arch, dental malocclusions, and dental crowding. It is imperative that clinicians recognize, diagnose, and begin treatment as early as possible when facial growth deviates from normal. Several specific diagnostic tools, coupled with traditional diagnostic records, assist the clinician in determining the degree and direction of atypical growth. Such a clear-cut diagnostic process sets in motion the treatment plan requirements necessary to accomplish the goal of returning facial growth to normal. Diagnosis and treatment planning requires that each practitioner has a broad base of knowledge, a good power of observation, and insight into the complex subject of facial growth and development.

The use of videofluoroscopy in the assessment of the pharyngeal airway in obstructive sleep apnoea.

This prospective cohort study evaluated the use of videofluoroscopy in assessing changes in both antero-posterior (A-P) and transverse pharyngeal airway dimensions in patients with obstructive sleep apnoea (OSA). Forty patients [32 males and 8 females; mean age of 49.3 (SD = 10.79) years] with confirmed OSA, referred for mandibular advancement appliance (MAA) therapy were recruited. Patients received a customized Herbst MAA, adjusted for maximum comfortable protrusion. A standard lateral cephalogram, supine A-P, and transverse videofluoroscopic investigations were performed. Repeat supine videofluoroscopic investigations were undertaken with the MAA in situ. Parametric tests were used to evaluate the study hypotheses as the data were normally distributed. A paired t-test was employed to determine both the impact of posture on the airway using upright cephalometry and supine videofluoroscopy and the effect of MAA insertion on A-P and transverse pharyngeal airway dimensions. Following a change in posture from upright to supine, highly statistically significant (P < 0.001) changes were observed for all lateral pharyngeal dimensions. Statistically significant increases in minimum lingual airway (P < 0.001) and maximum transverse pharyngeal airway (P < 0.001) were found following MAA insertion. A reduction in soft palate area (P = 0.029) and pharyngeal height (P < 0.001) was also noted. Videofluoroscopy offers a useful dynamic assessment of the pharyngeal airway in both the A-P and transverse planes in patients with OSA.

Assessment of mandibular growth and response to functional appliance treatment in prepubertal patients with different auxologic categories.

OBJECTIVE: To assess mandibular growth and response to functional appliance treatment in different Petrovic's auxologic categories and to investigate diagnostic and prognostic usefulness of the Lavergne-Petrovic's flow diagram. MATERIALS AND METHODS: Eighteen patients with class II malocclusion (ANB>/=4 degrees , dental class II) were selected and divided into 4 groups according to the auxologic categories. Category 2 group had 4 patients, category 3 group had 5, category 4 group had 5 and category 5 group had 4. In order to obtain patient's growth curves and detect the correct treatment time, patient's height was measured every 3 months. This method was supported by the cervical vertebral maturation method for the assessment of mandibular growth. Functional appliance and/or class II elastics, during the fixed appliance phase, were used to correct skeletal and dental relationships. Average treatment time was 31 months (Range 28-36 months). CoGn and ANB were detected in pre-treatment and post-treatment radiographs in order to assess mandibular growth. RESULTS: The highest growth was in category 5, the lowest in category 2. Rotational type improvement was generally observed. CONCLUSIONS: In prepubertal class II patients, treatment success not only depends on appliance choice, clinician's ability and correct treatment time, but also on individual growth potential and facial type. Therefore Lavergne-Petrovic's flow diagram could become a great diagnostic and prognostic aid for the orthodontist.

Early treatment for Class II Division 1 malocclusion with the Twin-block appliance: a multi-center, randomized, controlled trial.

INTRODUCTION: The aim of this study was to evaluate the effectiveness of early orthodontic treatment with the Twin-block appliance for the treatment of Class II Division 1 malocclusion. This was a multi-center, randomized, controlled trial with subjects from 14 orthodontic clinics in the United Kingdom. METHODS: The study included 174 children aged 8 to 10 years with Class II Division 1 malocclusion; they were randomly allocated to receive treatment with a Twin-block appliance or to an initially untreated control group. The subjects were then followed until all orthodontic treatment was completed. Final skeletal pattern, number of attendances, duration of orthodontic treatment, extraction rate, cost of treatment, and the child's self-concept were considered. RESULTS: At the end of the 10-year study, 141 patients either completed treatment or accepted their occlusion. Data analysis showed that there was no differences between those who received early Twin-block treatment and those who had 1 course of treatment in adolescence with respect to skeletal pattern, extraction rate, and self-esteem. Those who had early treatment had more attendances, received treatment for longer times, and incurred more costs than the adolescent treatment group. They also had significantly poorer final dental occlusion. CONCLUSIONS: Twin-block treatment when a child is 8 to 9 years old has no advantages over treatment started at an average age of 12.4 years. However, the cost of early treatment to the patient in terms of attendances and length of appliance wear is increased.

[Orthodontics in general practice 3. Angle Class II/1 malocclusion: one-phase treatment treatment preferred to two-phase treatment]. / Orthodontie in de algemene tandartspraktijk 3. Angle Klasse II/1-malocclusie: beter een latere éénfase- dan een vroege tweefasenbehandeling.

With regard to the optimal treatment timing for children with an Angle Class II division 1 malocclusion, there is an ongoing controversy on the effectiveness of a two-phase or a one-phase therapy. Two-phase treatment involves a first phase to correct the jaw relationship starting at the age of 7 to 9 years, and, when all permanent teeth are present, a second phase of treatment by fixed appliances. A one-phase treatment involves treatment of the jaw relationship and the dental malocclusion simultaneously or consecutively, starting during the early adolescence period. In recent years, several randomized controlled clinical trials have been performed on this topic. More recently, a Cochrane meta-analysis of these trials has been published. The results show that early treatment of an Angle Class II division 1 malocclusion followed by a second phase of treatment does not have any advantages over treatment that is started later and finished in one phase. One-phase treatment is as effective as two-phase treatment, while the time needed for treatment is shorter and, as a consequence, total costs are lower. Dentists should take into account this information, when treating children with an Angle Class II division 1 malocclusion or referring them to an orthodontist.

Oral appliances and functional orthopaedic appliances for obstructive sleep apnoea in children.

BACKGROUND: Apnoea is a breathing disorder marked by the absence of airflow at the nose or mouth. In children, risk factors include adenotonsillar hypertrophy, obesity, neuromuscular disorders and craniofacial anomalies. The most common treatment for obstructive sleep apnoea syndrome (OSAS) in childhood is adenotonsillectomy. This approach is limited by its surgical risks, mostly in children with comorbities and, in some patients, by recurrence that can be associated with craniofacial problems. Oral appliances and functional orthopaedic appliances have been used for patients who have OSAS and craniofacial anomalies because they change the mandible posture forwards and potentially enlarge the upper airway and increase the upper airspace, improving the respiratory function. OBJECTIVES: To assess the effectiveness of oral appliances or functional orthopaedic appliances for OSAS in children. SEARCH STRATEGY: A sensitive search was developed for the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2005, Issue 3); PubMed (January 1966 to September 2005); EMBASE (1980 to September 2005); Lilacs (1982 to September 2005); BBO-Bibliografia Brasileira de Odontologia (1986 to September 2005); and SciELO (1997 to September 2005). There was no restriction of language or source of information. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials comparing all types of oral and functional orthopaedic appliances with placebo or no treatment, in children 15 years old or younger. PRIMARY OUTCOME: reduction of apnoea to less than one episode per hour. SECONDARY OUTCOMES: dental and skeletal relationship, sleep parameters improvement, cognitive and phonoaudiologic function, behavioural problems, drop outs and withdrawals, quality of life, side effects (tolerability), economic evaluation. DATA COLLECTION AND ANALYSIS: Data were independently extracted by two review authors. Authors were contacted for additional information. Risk ratios with 95% confidence intervals were calculated for all important dichotomous outcomes. MAIN RESULTS: The initial search identified 384 trials. One of them, reporting results from a total of 23 patients, was suitable for inclusion in the review. Data provided in the published report did not answer all the questions from this review, but some of them were, and the presented results favour treatment. AUTHORS' CONCLUSIONS: At present there is no sufficient evidence to state that oral appliances or functional orthopaedic appliances are effective in the treatment of OSAS in children. Oral appliances or functional orthopaedic appliances may be helpful in the treatment of children with craniofacial anomalies which are risk factors for apnoea.

Assessment of mandibular growth and response to orthopedic treatment with 3-dimensional magnetic resonance images.

INTRODUCTION: Three-dimensional (3D) craniofacial images are commonly used in clinical studies in orthodontics to study developmental and morphologic relationships. METHODS: We used 3D magnetic resonance imaging to study relationships among craniofacial components during the pubertal growth spurt and in response to Fränkel appliance therapy. The sample for this prospective study was 156 high-resolution magnetic resonance images with 1 mm isotropic voxel resolution of 78 subjects taken initially (T1) and 18 +/- 1 months (T2) after treatment or an observation period. The subjects were Brazilian children; 28 were treated and 25 were untreated for Class II malocclusion, and 25 were untreated with normal occlusions. A Procrustes geometric transformation of 3D skeletal landmarks was used to assess growth or treatment alterations from T1 to T2. The landmarks were located on the mandibular rami and the other craniofacial parts specifically related to the mandibular growth (the middle cranial fossae and the posterior part of the bilateral nasomaxilla). This allowed visualization of the entire volumetric dataset with an interactive 3D display. RESULTS: Statistically significant differences were found in the relative 3D skeletal growth directions from T1 to T2 for treated vs untreated Class II children (Bonferroni-adjusted P < .001) and for treated Class II vs normal-occlusion subjects ( P < .001). The major differences in the treated group were increased mandibular rami vertical dimensions and more forward rami relative to the posterior nasomaxilla and the middle cranial fossae. Principal component analysis made it possible to show individual variability and group differences in the principal dimensions of skeletal change. CONCLUSIONS: These methods are generalizable to other imaging techniques and 3D samples, and significantly enhance the potential of systematically controlled data collection and analysis of bony structures in 3 dimensions for quantitative assessment of patient parameters in craniofacial biology.