Evaluation of external apical root resorption caused by fixed functional treatment of class II malocclusion : Cast splint Herbst appliance vs. Forsus fatigue resistant device.

INTRODUCTION: The aim of this study was to evaluate and compare the effects of class II fixed functional treatment with a cast splint Herbst appliance (HA; Herbst Set I, Dentaurum, Ispringen, Germany) and Forsus fatigue resistant device (FRD; 3M Unitek Corp., Monrovia, CA, USA) on external apical root resorption (EARR) in posterior teeth. METHODS: In all, 40 patients (15 male and 25 female) with class II division 1 malocclusion were treated with two fixed functional appliances: HA (20 patients, mean age 14.60 ± 1.14 years) and FRD (20 patients, mean age 14.15 ± 1.28 years). The vestibular lengths of the first molars and premolars were measured on panoramic radiographs and converted to actual tooth length using the magnification coefficient (MC), which was calculated using dental models. Intragroup comparisons of pre- and posttreatment tooth lengths were performed with the paired t­test and Wilcoxon signed-rank test, while intergroup comparisons were performed with the Mann-Whitney U test. RESULTS: Pretreatment tooth length values decreased significantly with HA and FRD therapies for all posterior teeth. The maximum resorption was observed in the mandibular first premolar with a mean of 0.81 mm following HA and 1.55 mm following FRD treatment. While no significant difference existed between the EARR values of the HA and FRD groups for maxillary teeth, the amount of EARR of mandibular posterior teeth in the FRD group was significantly higher than in the HA group. CONCLUSIONS: In patients treated with HA or FRD, the tooth length of posterior teeth decreased to a clinically minor but statistically significant degree. The root resorption effect of FRD therapy in mandibular posterior teeth was significantly higher than that of HA therapy.

Long-term (≥15 years) effects of Class II treatment: a longitudinal and cross-sectional study on signs and symptoms of temporomandibular disorders.

BACKGROUND: The aetiology of temporomandibular disorders (TMD) is controversial and post-orthodontic long-term TMD data of Class II populations are scarce. OBJECTIVES: To analyse the long-term (≥15 years) effects of Herbst-multibracket appliances (MBA) Class II treatment (Tx) on signs and symptoms of TMD. SUBJECTS AND METHODS: All patients (University of Giessen, Germany) who underwent Herbst-MBA Tx (end of active Tx ≥ 15 years ago), could be located and agreed to participate in a recall. Available records from before (T0) and after (T1) active Tx were used for comparison with the recall data (T2). All findings were classified according to research diagnostic criteria for temporomandibular disorders (RDC/TMD) and diagnostic criteria for temporomandibular disorders (DC/TMD) as well as the Helkimo index. RESULTS: Seventy-two out of 152 patients participated at age 33.7 ± 3.0 years. Complete TMD data-sets (T0 + T1 + T2) were available for 33 participants. Participants and non-participants did not differ significantly at T0 or T1 in terms of general clinical data, occlusal relationship or TMD prevalence. At all time-points, 79-91 per cent of the patients were free of TMD signs and symptoms (RDC/TMD and DC/TMD). The TMD prevalence fluctuated: 21 per cent (T0), 9 per cent (T1), 15 per cent (T2). Similar findings with a trend towards improvement during T0-T1 and recurrence during T1-T2 were seen for the Helkimo index. There were no statistically significant differences. LIMITATIONS: The participation rate of only 62 per cent, the disparate availability of records (T0, T1), the fact that the patients were not treated at exactly the same time period and that no untreated control group is available. CONCLUSION: In the long-term (≥15 years) Herbst-MBA Class II Tx neither seems to increase nor decrease the risk for developing TMD.

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.

Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents.

BACKGROUND: Prominent upper front teeth are a common problem affecting about a quarter of 12-year-old children in the UK. The condition develops when permanent teeth erupt. These teeth are more likely to be injured and their appearance can cause significant distress. Children are often referred to an orthodontist for treatment with dental braces to reduce the prominence of their teeth. If a child is referred at a young age, the orthodontist is faced with the dilemma of whether to treat the patient early or to wait and provide treatment in adolescence. OBJECTIVES: To assess the effects of orthodontic treatment for prominent upper front teeth initiated when children are seven to 11 years old ('early treatment' in two phases) compared to in adolescence at around 12 to 16 years old ('late treatment' in one phase); to assess the effects of late treatment compared to no treatment; and to assess the effects of different types of orthodontic braces. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 27 September 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 8), MEDLINE Ovid (1946 to 27 September 2017), and Embase Ovid (1980 to 27 September 2017). The US National Institutes of Health Ongoing Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials of orthodontic treatments to correct prominent upper front teeth (Class II malocclusion) in children and adolescents. We included trials that compared early treatment in children (two-phase) with any type of orthodontic braces (removable, fixed, functional) or head-braces versus late treatment in adolescents (one-phase) with any type of orthodontic braces or head-braces, and trials that compared any type of orthodontic braces or head-braces versus no treatment or another type of orthodontic brace or appliance (where treatment started at a similar age in the intervention groups).We excluded trials involving participants with a cleft lip or palate, or other craniofacial deformity/syndrome, and trials that recruited patients who had previously received surgical treatment for their Class II malocclusion. DATA COLLECTION AND ANALYSIS: Review authors screened the search results, extracted data and assessed risk of bias independently. We used odds ratios (ORs) and 95% confidence intervals (CIs) for dichotomous outcomes, and mean differences (MDs) and 95% CIs for continuous outcomes. We used the fixed-effect model for meta-analyses including two or three studies and the random-effects model for more than three studies. MAIN RESULTS: We included 27 RCTs based on data from 1251 participants.Three trials compared early treatment with a functional appliance versus late treatment for overjet, ANB and incisal trauma. After phase one of early treatment (i.e. before the other group had received any intervention), there was a reduction in overjet and ANB reduction favouring treatment with a functional appliance; however, when both groups had completed treatment, there was no difference between groups in final overjet (MD 0.21, 95% CI -0.10 to 0.51, P = 0.18; 343 participants) (low-quality evidence) or ANB (MD -0.02, 95% CI -0.47 to 0.43; 347 participants) (moderate-quality evidence). Early treatment with functional appliances reduced the incidence of incisal trauma compared to late treatment (OR 0.56, 95% CI 0.33 to 0.95; 332 participants) (moderate-quality evidence). The difference in the incidence of incisal trauma was clinically important with 30% (51/171) of participants reporting new trauma in the late treatment group compared to only 19% (31/161) of participants who had received early treatment.Two trials compared early treatment using headgear versus late treatment. After phase one of early treatment, headgear had reduced overjet and ANB; however, when both groups had completed treatment, there was no evidence of a difference between groups in overjet (MD -0.22, 95% CI -0.56 to 0.12; 238 participants) (low-quality evidence) or ANB (MD -0.27, 95% CI -0.80 to 0.26; 231 participants) (low-quality evidence). Early (two-phase) treatment with headgear reduced the incidence of incisal trauma (OR 0.45, 95% CI 0.25 to 0.80; 237 participants) (low-quality evidence), with almost half the incidence of new incisal trauma (24/117) compared to the late treatment group (44/120).Seven trials compared late treatment with functional appliances versus no treatment. There was a reduction in final overjet with both fixed functional appliances (MD -5.46 mm, 95% CI -6.63 to -4.28; 2 trials, 61 participants) and removable functional appliances (MD -4.62, 95% CI -5.33 to -3.92; 3 trials, 122 participants) (low-quality evidence). There was no evidence of a difference in final ANB between fixed functional appliances and no treatment (MD -0.53°, 95% CI -1.27 to -0.22; 3 trials, 89 participants) (low-quality evidence), but removable functional appliances seemed to reduce ANB compared to no treatment (MD -2.37°, 95% CI -3.01 to -1.74; 2 trials, 99 participants) (low-quality evidence).Six trials compared orthodontic treatment for adolescents with Twin Block versus other appliances and found no difference in overjet (0.08 mm, 95% CI -0.60 to 0.76; 4 trials, 259 participants) (low-quality evidence). The reduction in ANB favoured treatment with a Twin Block (-0.56°, 95% CI -0.96 to -0.16; 6 trials, 320 participants) (low-quality evidence).Three trials compared orthodontic treatment for adolescents with removable functional appliances versus fixed functional appliances and found a reduction in overjet in favour of fixed appliances (0.74, 95% CI 0.15 to 1.33; two trials, 154 participants) (low-quality evidence), and a reduction in ANB in favour of removable appliances (-1.04°, 95% CI -1.60 to -0.49; 3 trials, 185 participants) (low-quality evidence). AUTHORS' CONCLUSIONS: Evidence of low to moderate quality suggests that providing early orthodontic treatment for children with prominent upper front teeth is more effective for reducing the incidence of incisal trauma than providing one course of orthodontic treatment in adolescence. There appear to be no other advantages of providing early treatment when compared to late treatment. Low-quality evidence suggests that, compared to no treatment, late treatment in adolescence with functional appliances, is effective for reducing the prominence of upper front teeth.

Comparison of complications in the conventional telescopic Herbst rod and tube and Manni telescopic Herbst: A retrospective clinical study.

OBJECTIVES: To compare the prevalence of clinical complications between two different telescopic Herbst systems: the conventional telescopic system, with traditional rod and tube (RMS), and the Manni telescopic Herbst appliance (MTH). MATERIALS AND METHODS: Ninety subjects treated with RMS were compared to 89 patients treated with MTH. All of the complications that occurred were reported, and percentages of prevalence were calculated. RESULTS: MTH showed a significantly lower percentage of reversible complications (that did not require appliance removal) when compared to the reversible complications during RMS treatment (20.2% vs 51.1%). No statistically significant differences were found between RMS and MTH regarding irreversible complications (that required appliance removal and full re-make). All of the irreversible complications occurred after reversible complications in the RMS group, while most of the irreversible complications in the MTH group occurred without any previous reversible complication. CONCLUSIONS: MTH exhibited a smaller number of clinical complications during Class II skeletal malocclusion therapy.

Comparative evaluation of treatment effects between two fixed functional appliances for correction of Class II malocclusion: A single-center, randomized controlled trial.

OBJECTIVE: The objective of this study was to evaluate and compare the effects of PowerScope and Forsus in the treatment of Class II division 1 malocclusion. MATERIALS AND METHODS: This was a 2-arm parallel, double-blind, randomized, controlled trial. A total of 28 Class II division 1 malocclusion patients indicated for treatment with fixed functional appliances were randomized and equally divided (n = 14) among PowerScope (American Orthodontics, Sheboygan, Wis; mean age 14.11 ± 1.3 years) and Forsus (3M Unitek Corp, Monrovia, Calif; mean age 15.5 ± 1.1 years) groups. Skeletal and dentoalveolar effects of PowerScope and Forsus were compared. The secondary outcomes were evaluation of patient comfort and operator convenience. Randomization was accomplished with a 1:1 allocation ratio, and concealment was achieved by sealed opaque envelopes. The participants and data collectors were all blinded to study group allocation. Data were analyzed for 26 patients, 13 in each group, as one patient from each group discontinued treatment. Statistical comparisons were carried out using Student's t-tests and chi square tests ( P ≤ .05). RESULTS: A significantly greater mesial mandibular movement and improvement in sagittal skeletal relation were found in the Forsus patients ( P ≤ .05). The forward movement of the mandibular molar and incisors were greater in the PowerScope patients (2.3 mm and 2.80 mm) than in the Forsus patients (1.9 mm and 2.38 mm). CONCLUSIONS: Both PowerScope and Forsus are effective in correcting Class II malocclusion. The percentage of dentoalveolar effects in correcting Class II malocclusion is more for PowerScope when compared with Forsus. Patient comfort was the same with both appliances. This trial was registered.

Comparison of Complications in Removable Mandibular Acrylic Splint and Cantilever Herbst for Management of Class II Malocclusion: A Retrospective Study.

INTRODUCTION: Numerous appliances are present for the management of class II malocclusion. We have conducted a study to compare the clinical complications during treatment with either a removable mandibular acrylic splint (RMS) or with a cantilever Herbst (HC) appliance for the management of class II malocclusion. MATERIALS AND METHODS: This study consisted of records of 114 patients (61 males, 53 females), who were divided into two groups. Group I received RMS and group II received HC for the treatment of class II, Division 1 malocclusion. They were further subdivided according to the telescopic system used [Dentaurum type I or propulsor mandibular abzil (PMA)] and fixation mode (splint with crowns or GripTite bands). Patients' clinical records were assessed to identify clinical complications. RESULTS: The results of the study showed that the incidence of complications during treatment in both groups was statistically nonsignificant. The complications with either crown or band were also statistically nonsignificant. The Dentaurum group showed more susceptibility to complications than the PMA group. CONCLUSION: The PMA telescopic system is more efficient as compared with Dentaurum. Complication resulting from Herbst appliance is independent type of appliance used and mode of fixation. CLINICAL SIGNIFICANCE: Herbst appliance is the treatment of choice for class II malocclusion.

Skeletal effects in Angle Class II/1 patients treated with the functional regulator type II : Cephalometric and tensor analysis.

OBJECTIVES: The purpose of this work was to employ both cephalometric and tensor analysis in characterizing the skeletal changes experienced by patients with Angle Class II/1 malocclusion during functional orthodontic treatment with the functional regulator type II. METHODS: A total of 23 patients with Class II/1 malocclusion based on lateral cephalograms obtained before and after treatment with the functional regulator type II were analyzed. Another 23 patients with Angle Class II/1 malocclusion who had not undergone treatment were included as controls. RESULTS: Our cephalometric data attest to significant therapeutic effects of the functional regulator type II on the skeletal mandibular system, including significant advancement of the mandible, increases in effective mandibular length with enhancement of the chin profile, and reduction of growth-related bite deepening. No treatment-related effects were observed at the cranial-base and midface levels. In addition, tensor analysis revealed significant stimulation of mandibular growth in sagittal directions, without indications of growth effects on the maxilla. Its growth-pattern findings differed from those of cephalometric analysis by indicating that the appliance did promote horizontal development, which supports the functional orthodontic treatment effect in Angle Class II/1 cases. CONCLUSIONS: Tensor analysis yielded additional insights into sagittal and vertical growth changes not identifiable by strictly cephalometric means. The functional regulator type II was an effective treatment modality for Angle Class II/1 malocclusion and influenced the skeletal development of these patients in favorable ways.

Upper airway changes following single-step or stepwise advancement using the Functional Mandibular Advancer.

OBJECTIVES: Purpose of the present study was to determine and compare possible changes in the dimensions of the pharyngeal airway, morphology of the soft palate, and position of the tongue and hyoid bone after single-step or stepwise mandibular advancement using the Functional Mandibular Advancer (FMA). PATIENTS AND METHODS: The sample included 51 peak-pubertal Class II subjects. In all, 34 patients were allocated to two groups using matched randomization: a single-step mandibular advancement group (SSG) and a stepwise mandibular advancement group (SWG). Both groups were treated with FMA followed by fixed appliance therapy; the remaining 17 subjects who underwent only fixed appliance therapy constituted the control group (CG). The study was conducted using pre- and posttreatment lateral cephalometric radiographs. Data were analyzed by paired t test, one-way analysis of variance, and Pearson's correlation coefficient. RESULT: In the SWG and SSG, although increases in nasopharyngeal airway dimensions were not significant compared with those in the CG, enlargements in the oropharyngeal airway dimensions at the level of the soft palate tip and behind the tongue, and decreases in soft palate angulation, were significant. Tongue height increased significantly only in the SWG. Compared with the CG, while forward movement of the hyoid was more prominent in SSG and SWG, the change in the vertical movement of the hyoid was not significant. No significant difference between SWG and SSG was observed in pharyngeal airway, soft palate, tongue or hyoid measurements. CONCLUSIONS: The mode of mandibular advancement in FMA treatment did not significantly affect changes in the pharyngeal airway, soft palate, tongue, and hyoid bone.

Herbst plus Lingual versus Herbst plus Labial: a comparison of occlusal outcome and gingival health.

OBJECTIVES: To analyse and compare the effects during Herbst treatment combined with a lingual (completely customized) or labial (straight-wire) multibracket appliance (MBA), with special regard to lower incisor gingival recessions. SUBJECTS AND METHODS: Eighteen Class II:1 patients [overjet ≥ 5mm, Class II molar relationship ≥ 0.5 cusp widths (CW) bilaterally or 1.0 CW unilaterally, median age 16.0 years] treated with a Herbst appliance in combination with a lingual MBA (group LINGUAL) were retrospectively matched (molar relationship and skeletal maturity) to 18 Class II:1 patients treated with a Herbst appliance combined with a labial MBA (group LABIAL). Study models and intraoral photographs from before and after treatment were evaluated regarding occlusal variables and gingival recessions. Lateral cephalograms from before, during (before and after Herbst), and after treatment were analysed to assess lower incisor changes. RESULTS: Both groups showed similar reductions of overjet (5.4/5.6mm), overbite, (2.9/2.7mm) and sagittal molar relationship (0.9/0.8 CW). During the Herbst phase, the changes in lower incisor inclination and incisal edge position were significantly smaller in the LINGUAL than in the LABIAL group (iiL/ML: +7.0/+12.7degrees, P = 0.002; ii-MLppg: +2.5/+3.9mm, P = 0.004). For the total treatment period, no significant differences were found (iiL/ML: +5.3/+8.6degrees; ii-MLppg: +2.1/+2.4mm). No clinically relevant gingival recessions were seen. CONCLUSION: Both treatment approaches successfully corrected the malocclusion. The group LINGUAL exhibited significantly less proclination during the Herbst phase only. Neither treatment approach induced deleterious gingival recessions.

Cone beam computed tomography study of apical root resorption induced by Herbst appliance.

OBJECTIVE: This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT). MATERIAL AND METHODS: The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates' correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%. RESULTS: Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders. CONCLUSION: CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.

Cone beam computed tomography study of apical root resorption induced by Herbst appliance

Objective This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT).Material and Methods The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates’ correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%.Results Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders.Conclusion CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.

Clinical complications during treatment with a modified Herbst appliance in combination with a lingual appliance.

OBJECTIVE: To assess the types and frequencies of clinical complications experienced when using a modified lingual Herbst appliance and to compare these with those associated with conventional Herbst appliances reported in the literature. METHODS: Treatment records for 35 consecutive subjects treated during the observation period from October 2013 to August 2014 who received a combination of a lingual appliance and a modified Herbst appliance (WIN, DW LingualSystems) were assessed for complications linked to Herbst treatment phase. Complications were analyzed descriptively, and complication-free intervals were calculated using Kaplan-Meier plots. To enable a comparison with data reported in the literature, the cumulative treatment time for all subjects was divided by the total number of complications. RESULTS: 71.4% of Herbst treatments were free from complications (n = 25). Complications were seen on 13 occasions (8 instances of Herbst attachment loosening, 5 L-Pin fractures). Most of these complications could be fixed chair side utilizing simple clinical measures. Considering all complications as identical statistical events, the percentage of treatments free from complications would be 88% for 100 days, 70% for 200 days and 56.8% for 300 days. For severe complications, the averaged complication-free treatment interval was found to be 27.8 months. CONCLUSION: In terms of clinical sturdiness, and taking into consideration the step-wise mode of activation used here as well as the differences in the design of the various Herbst appliances, the WIN-Herbst appliance was found to be superior to comparable vestibular Herbst appliances, as well as the banded Herbst appliance belonging to the preceding generation of customized lingual systems. Success in treatment of non-compliant Angle Class II correction is considered to have better predictability using the modified anchorage strategy of the WIN-Herbst appliance.

Retrospective study of clinical complications during orthodontic treatment with either a removable mandibular acrylic splint Herbst or with a cantilever Herbst.

OBJECTIVE: To compare the clinical complications during treatment with either a removable mandibular acrylic splint (RMS) or with a cantilever (HC) Herbst appliance. METHODS: Records from 159 Class II, division 1, consecutively treated patients with a Herbst appliance were examined. The sample was composed of 82 male and 77 female patients with a mean age of 11.8 years. The Herbst appliance was used for a mean of 12 months (standard deviation 2.15 months). Two main Herbst groups were analyzed: group RMS (n  =  125) and group HC (n  =  34). They were further subdivided according to the telescopic system used (Dentaurum type 1 or PMA) and fixation mode (splint with crowns or Grip Tite bands). Patients' clinical records were assessed to identify clinical complications. RESULTS: The incidence of complications during treatment was 85.3% for the HC group and 88.0% for the RMS group, with no statistically significant difference (Mann-Whitney test, P > .05). The fixation mode (crown or band) also did not show a statistically significant difference (P > .05). Regarding the telescopic system used, the Dentaurum group had 2.9 times more susceptibility to complications than the PMA group, regardless of the Herbst type. CONCLUSIONS: On average, approximately 2.5 complications per patient were reported. Most patients had a maximum of three complications during Herbst treatment. Herbst appliance type (RMS or HC) and fixation mode (crowns or Grip Tite bands) did not influence the number of complications. The PMA (without screws) telescopic system seemed to be more reliable (regarding the number of complications) than Dentaurum type 1, regardless of the appliance design (RMS or HC).

Acrylic splint Herbst and Hanks telescoping Herbst: a retrospective study of emergencies, retreatments, treatment times and failures.

INTRODUCTION: The Herbst appliance has been reported to be one of the most efficient for the correction of class II malocclusions. However, there are many complications that make its use difficult for clinicians and patients (splint loosening, telescope breakage, splint breakage, low comfort). The aim of this study was to evaluate and compare emergencies, retreatments, failures and overall treatment time of two types of Herbst appliances: the HT Herbst and the acrylic splint Herbst. MATERIALS AND METHODS: Two hundred and eight patients with Class II malocclusion were selected consecutively in a private practice. They were treated either with an acrylic splint Herbst (155 pt, mean age 10.3 ± 3.7) or with a HT Herbst (53 pt, mean age 11.3 ± 4.2 years). Tables were used for each patient to record the following complications, if present: detached Herbst, broken and repaired Herbst, broken and rebuilt Herbst (emergencies), Herbst that had to be re-made for lack of patient cooperation (retreatments) and appliances that had to be removed (failed treatment). RESULTS: Results showed that the HT Herbst and the acrylic splint Herbst have the same retreatment probability and the same treatment time. Moreover, the HTH has a lower risk of functional impairment: the acrylic splint Herbst has an emergency probability that is twice as high as the HTH. On the other hand, the HTH has a failure frequency that is nearly 6 times higher than the traditional Herbst although the statistical analysis could not provide any certain conclusion about it. CONCLUSION: In cases where a higher relative risk of failure for the traditional Herbst was confirmed, the HTH proved to be a better appliance than the traditional Herbst.

Tratamento precoce de más-oclusões esqueléticas de Classe II - comparação de três aparelhos ortopédicos funcionais: Bionator, Klammt, SN1 / Early treatment of skeletal Class II malocclusions – comparison of three functional appliances: Bionator, Klammt, SN1

Objetivo: comparar no plano sagital os efeitos esqueléticos e dentoalveolares para a maxila e mandíbula, como consequência do uso dos aparelhos Bionator, Klammt e SN1 no tratamento de más-oclusões esqueléticas Classe II. Material e métodos: foi realizado um estudo prospectivo de 21 crianças com má-oclusão esquelética de Classe II, tratadas com Bionator, Klammt ou SN1. Compararam-se mudanças no componente maxilar, mandibular e dentoalveolar através de medições e ângulos cefalométricos no plano sagital. Contrastaram-se as médias de longitudes e ângulos entre T1 e T2 pelas análises t student e wilcononox. Mediante Anova, foi contrastada a porcentagem da mudança nas medidas de interesse para os três grupos. Resultados: foram avaliadas 42 radiografias cefalométricas laterais (21 iniciais T1, 21 finais T2). Entre os participantes, 62% eram meninos e 38% eram meninas. A média das idades para início do tratamento foi 9,5 ± 1,2 anos. O SN1 apresentou a maior média de mudança na longitude mandibular Co-Pg (6,69 ± 3,3) e Co-B (6,59 ± 1,42). Encontrou-se a maior média de mudança relativa na altura do ramo mandibular no Bionator (9,52 ± 7,21). As mudanças dentoalveolares foram clinicamente relevantes para os três aparelhos. Conclusão: os aparelhos ortopédicos maxilares estimulam o crescimento mandibular sagital e vertical, controlam a posição sagital da maxila e geram mudanças dentoalveolares favoráveis para a correção de más-oclusões de Classe II.

Objective: comparing in the sagittal plane the skeletal and dento alveolar effects for the maxilla and the mandible as a result of the use of Bionator, Klammt and SN1 as a treatment of malocclusions class II skeletal. Material and Methods: a prospective study was realized on 21 boys and girls with skeletal Class II malocclusion under treatment with Bionator, Klammt or SN1, in which compare the changes in the maxillary, mandibular and dento-alveolar component by means of measurements and cephalometric angles in the sagittal plane. The averages of lengths and angles between T1y T2 was compare by t-student and wilcoxon tests. By Anova tests, contrasted the percentage of change in the measures of importance for the three groups. Results: 42 lateral skull radiographs were evaluated (21 initial-T1, 21 final-T2). 62% of participants were male and 38% were women. The average age for onset of treatment was 9.5 ± 1.2. The SN1 presented the highest average percent of change of the Co-Pg mandibular length (6.69 ± 3.3), Co-B (6.59 ± 1.42). A higher average relative change in the height of the ramus was found in Bionator (9.52 ± 7.21). Dento alveolar changes were clinically relevant for all three devices. Conclusion: orthopedic appliances stimulate mandibular sagittal and vertical growth, control the sagittal position of the maxilla, and generate favorable dento alveolar changes to correct class II malocclusions.

Adolescent patients' experience with the Carriere distalizer appliance.

AIM: To examine adolescent patients' experience with the Carriere Distalizer Appliance (CDA) and compare it with that of the Forsus Fatigue Resistant Device (FFRD). MATERIALS AND METHODS: A survey was administered to 42 patients treated with the CDA and 70 patients treated with the FFRD. Amount of time required to become accustomed to the appliance, how many patients experienced side effects as well as the degree of discomfort were explored. RESULTS: The overall experience with the device was significantly better for the CDA group than for the FFRD group. Both groups felt that delivery and removal of the appliance was quick and easy, the appliance was noticeable to some extent, and the majority became accustomed to it within two weeks with a maximum of one month. In general, associated discomfort and effects on daily life and activities were less for the CDA group than for the FFRD group. Side effects decreased over time for both groups, often more so for the CDA group. The major side effects experienced by the CDA group were difficulty eating and sore teeth, and these improved significantly over time. Soreness from the appliance rubbing on the cheek or lip was significantly less for the CDA group. CONCLUSION: The CDA appears to be more comfortable, offers a more positive overall experience, and has fewer negative comfort-related side effects compared to FFRD.

Patient experiences with the Forsus Fatigue Resistant Device.

OBJECTIVE: To investigate patients' experiences with the Forsus Fatigue Resistant Device (FFRD). METHODS: This was a survey focused on patient's comprehensive experience with FFRD, both initially and after several months of wear, including the patient's overall impression of the appliance. The survey was administered to 70 patients wearing FFRD in both university and private practice settings. RESULTS: A high percentage (81.5%) reported a neutral to favorable experience with FFRD; 89.8% reported growing accustomed to the appliance within 4 weeks. The majority of those who had previously worn rubber bands found FFRD to be "easier." Cheek irritation was the most serious side effect (about 50%). Cheek irritation and other negative effects generally decreased over time. CONCLUSIONS: The FFRD is relatively well accepted by patients. Most patients experience some discomfort and functional limitations; however, the effect generally diminishes with time, and patients adapt to the appliance. Practitioners should be especially vigilant about problems with cheek irritation.

Estudo prospectivo dos efeitos dentoesqueléticos e tegumentares do aparelho Twin-block comparado aos do Bionator no tratamento de má-oclusão de Classe II com retrognatismo mandibular / Study of dentoskeletal and soft tissue effects of Twin-block appliance compared to Bionator effects in the treatment of Class II malocclusion with mandibular retrognatism

Este estudo teve como objetivo avaliar as alterações dentoesqueléticase tegumentares do aparelho Twin-block em 21 jovensbrasileiros, de ambos os gêneros, com idade média de 10,5 anos(mínimo: 9,25 anos; máximo: 12,5 anos) portadores de rná-oclusão deClasse II com retrognatismo mandibular, tratados prospectivamente,e comparar as duas amostras retrospectivas, uma tratada com oaparelho ortopédico Bionator (22 jovens, com idade média de 10,42anos; mínimo: 8,08 anos; máximo: 12,58 anos) e um grupo controlede Classe II não tratado (24 jovens, com idade média de 9,97 anos;mínimo: 8,33 anos; máximo: 11,67 anos). As 134 telerradiografias emnorma lateral foram obtidas em T1 (antes do tratamento) e T2 (final dotratamento ortopédico). Todos os pacientes se encontravam no estágiode maturação das vértebras cervicais CVMSII em T1, Anova, teste deTukeye teste t pareado foram aplicados. Os resultados mostraram queos dois aparelhos corrigiram as relações maxilomandibular e dentárias,reduzindoa severidade da má-oclusão de Classe II, porém, com maioresresultadosesqueléticos no grupo Twin-block, como protrusão mandibular,crescimento do corpo e ramo mandibular; aumento das alturas faciais,posterior e da AFAI.O grupo Bionator teve protrusão e vestibularizaçãodos incisivos inferiores, enquanto o grupo Twin-block modificado teveretrusão e lingualização dos mesmos. Oaparelho Twin-block modificadopromoveumaior controle vertical que o aparelho Bionator, que tendeu apioraro padrão de crescimento. Além disso, o perfil mole com aparelhoTwin-blockmodificado ficou melhor que com o Bionator.

This study had as aim to assess the dentoskeletal andsott tissue effects ot the Twin-black appliance in 21 Brazilian subjectsof both genders, mean age of 10.5 years, minimum: 9.25 years; maximum:12.5 years with Class II malocclusion associated to a mandibularretrognathism prospectively treated and compare to two retrospectivesamples, one treated with Bionator appliance (22 subjects, 10.42years, minimum: 8.08 years; maximum: 12.58 yeers), and an untreatedClass II control group (24 subjects, 9.97 yeers, minimum: 8.33 years;maximum: 11.67 years). Ali patients were in cervical vertebral maturationstage CVMSII in T1, The 134 lateral cephalometric radiographswere obtained in T1 (initial) and T2 (final of the orthopedic fase arobservation time). Analysis of Variance (Anova), Tukey test and pared ttest were applied Theresults showed that ali appliances corrected themaxillomandibular relationship, dental relationships reducing the Class IImalocclusion severity with more skeletal effects as mandibular protrusion,mandibular growth, body and ramus, increase of facial heights,posterior and LAFH with Twin-block. Bionator group had significantprotrusion and vestibular inclination of the lower incisors and modifiedTwin-block had retrusion and retroclination of them. Modified Twin-blockpromoted greater vertical control than Bionator that trend to becomethe growth pattern worse. Besides, the sott profile with the modifiedTwin-block was better than with Bionator.