To compare skeletodental and soft tissue changes in growing Class II patients treated with Herbst or Pendex appliances, followed by fixed edgewise appliances, using two-dimensional lateral cephalometric radiographs extracted from three-dimensional cone-beam computed tomography scans. Forty-six patients were examined: 23 treated with Herbst (12.07 ± 1.49years, 12 males/11 females) and 23 with Pendex (11.76 ± 1.18years, 10 males/13 females). CBCT-derived lateral cephalograms were analyzed at T1 (initial), T2 (6months post-Herbst removal or immediately post-Pendex removal), and T3 (final records after edgewise fixed appliance removal). Cephalometric analysis assessed skeletal, dental, and soft tissue changes. Repeated measures ANOVA analyzed within-group changes across the three time points, and t-tests were used to compare between-group differences at each time point and evaluate changes from T1 to T3. From T1 to T3, the Herbst group exhibited a significant decrease in the SNA angle, a non-significant increase in SNB, and significant increases in mandibular dimensions, including total length, body length, corpus length, and ramus height. In contrast, the Pendex group demonstrated stable SNA values, a significant increase in SNB, and mandibular dimensional changes comparable to those observed in the Herbst group. Vertically, both groups remained stable with no significant differences in skeletal vertical parameters. Overall, no significant between-group differences were observed in skeletal, dental, or soft tissue parameters between T1 and T3. We did not detect statistically significant differences in overall skeletal, dental, and soft tissue changes between the two groups.

ABSTRACT Objective To evaluate changes in the oropharyngeal airway (OP) with Herbst appliances using either dental or skeletal anchorage (HDA vs. HSA) in growing patients with Class II division 1 malocclusion. Design, Setting, and Participants Forty patients (12.6 ± 1.4 years) at the peak of pubertal growth were randomized (HDA= 20; HSA= 20), for 12 months. Outcomes: change in OP volume, airway length and cross-sectional areas (minimum, maximum, average), by CBCT. Results Thirty-four patients completed the study (HDA= 19; HSA= 15); and intention-to-treat (ITT) analysis was applied. Within-group analysis revealed a significant improvement for minimum axial area (HDA, p = .0061). Between-group comparisons showed significantly higher mean values in the HSA group for volume (p = .0044), airway length (p = .004), maximum cross-sectional area (p = .0188), and average area (p = .0122). Conclusions HSA and HDA increased OP dimensions in growing Class II patients. Although HSA did not demonstrate a statistically superior effect, the dimensional changes represent morphological adaptations. Long-term studies are required to determine respiratory benefits.

270 - Correction of severe Class II in a post-growth spurt patient using the Herbst appliance: A case report

602 - Three-dimensional comparison of the effects of Twin Block and Herbst appliances on the airway in growing Class II patients: RCT

491 - A Comparative Three-Dimensional Analysis of Skeletal and Dental Changes Induced by Herbst and PowerScope Appliances in Class II Malocclusion Treatment

55 - Comparison of the skeletal effects of the Herbst appliance in growing Class II patients with and without subdivision

Objective This study used three-dimensional (3D) stereophotogrammetry to compare changes in facial soft tissues of patients with skeletal class II malocclusion with mandibular retrognathia treated with orthognathic surgery (OS) or Herbst appliance (HA).Methodology This retrospective study included 15 adults treated with bilateral sagittal split osteotomy without genioplasty (OS) and 16 adults treated with HA. The patients were treated successfully, with class I occlusal relationships with normal overjet and overbite. Three-dimensional stereophotogrammetric records acquired in habitual occlusion from before and after fixed orthodontic treatment were analyzed. Lateral cephalometric radiographs were used to evaluate skeletal parameters and sagittal oropharyngeal airway length.Results In HA-group, mandibular corpus length, anterior facial height, posterior facial height, Bº, vertical angle, and mentolabial angle increased; lower facial width, mandibular angle, mandibular convexity angle, ANBº, and Aº decreased. In OS-group, mandibular length, mandibular corpus length, and facial convexity angle increased significantly compared with those in HA-group; posterior facial height, Bº, vertical angle, and mentolabial angle also increased, but mandibular angle and ANBº decreased significantly. Only a significant difference in coordinate changes was observed for the pogonion in the sagittal direction. According to the cephalometric analysis, SNBº and Pg-NA perpendicular measurements increased significantly in the OS group compared with the HA group. In both groups, sagittal oropharyngeal airway length increased significantly post-treatment, with no significant intergroup difference.Conclusion In patients treated with OS, skeletal advancement resulted in greater increases in mandibular and corpus lengths, along with forward positioning of the pogonion. Based on 3D soft tissue and cephalometric comparisons, the Herbst appliance seems to be a viable non-surgical alternative for young adults with moderate Class II malocclusion. Both treatment modalities also contributed to significant improvements in sagittal oropharyngeal airway length.

Caries risk trajectories in a changing oral health landscape. A longitudinal study of orthodontic patients across four decades.

BackgroundIt is generally accepted that the ideal time to benefit from functional therapy in Class II patients is during the circumpubertal growth period (CVM 3–4). However, in severe cases, early intervention during the mixed dentition phase may be indicated, particularly to reduce the risk of dental trauma and to protect the child from potential bullying. The aim of this study was to evaluate the effects of the Manni Telescopic Herbst (MTH) appliance in young patients with mixed dentition, comparing the outcomes with two control groups: one treated with Class II elastics and a Wilson arch, and the other with a removable functional appliance (Paolone-Kaitsas, PK).MethodsFollowing statistical matching for age, sex and pre-treatment overjet, lateral cephalograms taken at beginning (T0) and at appliance removal (T1) from 30 patients treated with the MTH appliance were compared with those of 15 patients treated with Class II elastics and 15 treated with the PK appliance.ResultsRegarding skeletal parameters, significant differences were observed in the mandibular sagittal position (SNB (T1-T0), p = 0.01) and in the relationships between skeletal bases (ANB (T1-T0), p = 0.03; Wits (T1-T0), p < 0.01), when comparing MTH and PK groups to the Class II elastics group. The Herbst group exhibited the most substantial skeletal changes. For dental variables, better incisor control was achieved with the removable PK appliance (Ii/GoGn T1-T0 1.513 ± 5.739, and Is/PP (T1-T0) 2.507 ± 6.482). No statistically significant difference was found regarding skeletal divergence (SN/GoGn (T1-T0), p = 0.38) when focusing on younger patients in mixed dentition phase.ConclusionBoth the fixed MTH appliance and the removable PK appliance produced greater skeletal effects compared to Class II intermaxillary elastics, even when applied during the mixed dentition phase. Although the PK group demonstrated better dentoalveolar control, when significant skeletal modifications are required in young patients with mixed dentition, the use of a fixed functional appliance - such as the Herbst - is preferable.

Objective: To systematically evaluate the evidence regarding the effectiveness of myofunctional appliances in the treatment of skeletal and dento-alveolar malocclusions, particularly class II malocclusions, and their integration with orofacial myofunctional therapy (OMT). Methods: A systematic search was conducted using the PubMed, Scopus, Embase, and Cochrane Library databases for articles published from 1990 to 2024. Embase and Cochrane Library databases for articles published from 1990 to 2024. Inclusion criteria were randomized controlled trials (RCTs), clinical trials, and longitudinal studies evaluating the impact of myofunctional devices on skeletal and dental structures. Inclusion criteria were RCTs, clinical trials, and longitudinal studies assessing the impact of myofunctional appliances on skeletal and dental structures. The PRISMA 2020 checklist was followed. Risk of bias was assessed using the Cochrane RoB-2 and ROBINS-I tools. Results: A total of 2634 studies were selected, 41 met the eligibility criteria. Out of 2634 studies screened, 41 met the eligibility criteria. The majority of studies focused on the Twin Block, Bionator, Frankel, Herbst, and Jasper Jumper appliances. Significant changes were observed at dento-alveolar levels, particularly in the reduction of overbite and Class II relationships of molars. Skeletal improvements (increase in SNB, reduction in ANB) were more modest and depended on growth stages. Studies combining OMT with device therapy have shown improved long-term stability and functional improvements. Conclusions: Myofunctional appliances are effective in correcting Class II malocclusions, primarily through dento-alveolar changes, with slight skeletal effects. The combination of OMT improves muscle tone, reduces relapses, and improves compliance. However, heterogeneity in study design and the lack of long-term RCTs warrant further research.

To explore early treatment practices and perceptions among members of the American Association of Orthodontists (AAO). Cross-sectional survey. Members of the AAO. An electronic questionnaire was pre-piloted and circulated via email to members of the AAO. The survey questions covered respondent demographics, clinical experience, preferred timing of intervention, treatment approaches and clinicians' perceptions with regard to early interceptive treatment. Descriptive statistics were performed. A total of 228 responses were obtained (response rate = 5.12%). Treatment was commonly timed using dental age (61%) and pubertal signs (61.8%). Several problems were treated in the mid-mixed dentition phase (8-9 years) including posterior crossbite (51.3%) increased overjet (41.7%), crowding (39.5%), space loss (41.23%) and anterior open bite (37.3%). Commonly reported treatment approaches included the use of sectional fixed appliances for treatment of anterior crossbite (81.6%), rapid palatal expander for treatment of posterior crossbite (63.6%) and anterior bite plane for deep overbite correction (62.7%). Herbst appliance (42.1%) and facemask (89%) were commonly prescribed for early correction of Class II and III, respectively. Lingual and palatal arches were commonly used to preserve arch length. The majority of respondents (60.1%) were proponents of two-phase orthodontic treatment. Early orthodontic treatment in the mid-mixed dentition stage was widely advocated for orthodontic intervention. Various malocclusions, including posterior and anterior crossbite, increased overjet, crowding, space loss and anterior open bite, were reported to be commonly addressed during this phase. Popular treatment approaches included sectional fixed appliances, Herbst appliance, facemask, rapid palatal expanders and anterior bite planes.

IntroductionSkeletal Class II malocclusion, commonly characterized by mandibular retrusion, affects a significant portion of the population and presents challenges in orthodontic correction. The Herbst Appliance has long been used for mandibular advancement, but traditional designs often lead to undesirable dental side effects and mechanical complications. This paper introduces the structural innovation and digital manufacturing of Full Digital Manni Telescopic Herbst (MTH) Appliance, a structurally innovative and digitally manufactured system aimed at enhancing clinical outcomes and reducing treatment failures.Materials and equipmentUtilizing a fully digital workflow, including CAD/CAM design, intraoral scanning, and additive manufacturing, the MTH appliance integrates a full-coverage mandibular splint, digitally designed and precision-engineered maxillary and mandibular components.ResultsThe clinical implementation of the MTH appliance demonstrates excellent fit and high mechanical reliability, reducing lower incisor proclination and offering a proper vertical control. Complications such as debonding or fractures can be significantly reduced and digital reproducibility allows for fast component replacement when needed.Discussion and conclusionThis design improves skeletal correction by enhancing anchorage, minimizing lower incisor proclination, and allowing precise vertical and sagittal control. The digital workflow not only improves fabrication accuracy and patient comfort but also facilitates easy component replacement and reduced chairside time. The MTH appliance sets a new benchmark in Class II treatment, blending digital precision with biomechanical effectiveness.

BackgroundSkeletal Class II malocclusion is commonly treated using mandibular advancement appliances during growth. Evaluating the comparative effectiveness of different appliances can help optimize treatment outcomes.ObjectivesThis study aimed to compare dental and skeletal outcomes of Class II malocclusion treatment using Herbst and PowerScope appliances in conjunction with fixed orthodontic therapy.MethodsThis retrospective comparative study included 46 consecutively treated patients in two university clinics: 26 with PowerScope and 20 with Herbst MiniScope. CBCT scans were obtained before and after treatment. Skeletal and dental changes were analyzed using maxillary and mandibular voxel-based regional superimpositions and cranial base registrations, aided by AI-based landmark detection. Measurement bias was minimized through the use of a calibrated, blinded examiner. No patients were excluded from the analysis. Due to the study’s retrospective nature, no prospective registration was performed; the institutional review board granted ethical approval.ResultsThe Herbst group showed greater anterior displacement at B-point and Pogonion than PowerScope (2.4 mm and 2.6 mm, respectively). Both groups exhibited improved maxillomandibular relationships, with PowerScope’s SNA angle reduced and Herbst’s SNB increased. Vertical skeletal changes were observed at points A, B, and Pog in both groups. Herbst also resulted in less lower incisor proclination and more pronounced distal movement of upper incisors.ConclusionBoth appliances effectively corrected Class II malocclusion. Herbst promoted more pronounced skeletal advancement, while PowerScope induced greater dental compensation. These findings may be generalizable to similarly aged Class II patients in CVM stages 3–4.

Background: Class II Division 1 malocclusion is often characterized by an increased overjet, which has traditionally been considered a negative predictor of aesthetic outcomes, treatment efficacy, and long-term stability. Although early two-phase treatment is generally perceived as less effective than a single-stage pubertal peak intervention, it may be beneficial in cases with concerns such as trauma risk or bullying. This study aimed to assess the relationship between initial overjet and sagittal correction (as measured by the ANB and WITS indices) to identify a threshold beyond which two-phase treatment might be more effective. Methods: A retrospective analysis was conducted on 58 patients (mean age: 9.01 years), all of whom were treated consecutively with the Manni Telescopic Herbst Appliance. Lateral cephalograms taken at the start (T0) and end (T1) of Herbst treatment were analyzed to evaluate changes in skeletal and dental parameters. Results: A significant positive correlation was found between higher initial overjet and increased skeletal sagittal correction. Specifically, for every 1 mm increase in overjet, there was a 0.65 mm reduction in the WITS index and a 0.30° decrease in the ANB angle (p &lt; 0.01). These effects were more pronounced when the initial overjet exceeded 8.0 mm. Conclusions: The Manni Telescopic Herbst Appliance demonstrated enhanced skeletal correction in patients with larger initial overjet values, particularly when the overjet exceeded 8.0 mm. This suggests that early two-phase treatment may be especially beneficial in such cases.

The BioBiteCorrector® (BBC) appliance was introduced as a further development of the Herbst appliance; however, there is no research comparing their treatment outcomes. Caucasian healthy patients with at least 5mm overjet were included and treated with either Herbst or BBC, both combined with fixed appliances, by one experienced orthodontist at a private practice in Switzerland. Treatment effectiveness was evaluated in terms of occlusal outcomes via the Peer Assessment Rating (PAR) and Index of Orthodontic Treatment Need (IOTN) indices, for which groups were matched at baseline. Data collection took place before bonding and after debonding and data was statistically analyzed with linear/logistic regressions at 5%. Each group was comprised of 58patients. Patient and treatment related characteristics did not demonstrate any clinically relevant differences at baseline. The overall treatment duration was 19.3±5.3 and 22.9±5.7months for the Herbst and BBC respectively (P<0.001). The main outcomes of absolute PAR reduction, % PAR reduction, PAR improvement, or great PAR improvement were not statistically significant between groups (P>0.05 in all instances); however, patients treated with Herbst had slightly worse overall IOTN scores (P<0.03). The findings did not significantly change after controlling for confounders. Both Herbst and BBC appeared to be equally effective in improving class II malocclusion, yet the BBC appliance led to slightly longer overall treatment duration.

Aim: Class II Division I malocclusion poses significant challenges in orthodontics. The combination of a Herbst appliance and miniscrew anchorage emerged as a practical solution to improve skeletal and dental outcomes. This study employed finite element analysis to evaluate the biomechanical effects of a miniscrew-supported Herbst appliance on mandibular advancement and dentition movement. Methods: High-definition CBCT scans captured the maxilla and mandible’s detailed dental anatomy. The scans were stored in DICOM format for seamless integration with Mimics software (Mimics Innovation Suite research version 21.0, Materialise NV, Leuven, Belgium) for 3D reconstruction and model refinement. The appliance, designed with a maxillary fixed palatal arch and mandibular acrylic splint connected by telescoping rods, incorporated titanium TADs and elastic chains. STL models were optimized in Geomagic x Design for finite element analysis in Abaqus, assigning validated mechanical properties for materials. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Tetrahedral C3D4 elements were used for meshing, ensuring a balance between computational efficiency and detailed anatomical representation. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Dynamic simulations in CATIA evaluated mandibular movement. FEA analyzed displacement across dentoalveolar structures along the X, Y, and Z axes to assess treatment efficacy and biomechanical stability. Results: The Z displacement analysis revealed that the incisal edges of the lower central, lateral, and canines shifted lingually by 0.41, 0.4, and 0.47 mm, respectively. Additionally, the apices of the lower central, lateral, and canines displaced backwards by 0.05 mm, 0.05 mm, and 0.07 mm, respectively. Conclusions: The appliance facilitated mandibular advancement, bodily retracted the lower incisors, well-controlled the upper ones, and mesial-tipped the upper posterior teeth. In contrast with traditional functional appliances, it caused the lower anterior teeth to move backwards, while skeletal anchorage overcame some shortcomings of nonsurgical treatments. This method might be a good treatment option for growing skeletal Class II patients.

To evaluate the coefficient of efficiency and effectiveness of removable and fixed functional appliances in classII malocclusion treatment. Search of studies in five databases (Medline via PubMed, Cochrane library, LILACS, SCOPUS, and SciELO) that measured mandibular skeletal changes following functional therapy was conducted until 15April2024. All study designs including randomized and controlled clinical trials (RCT), prospective and retrospective studies were included. Data were extracted independently by two authors from studies that fulfilled the inclusion criteria. Mandibular length changes of classII patients treated with functional appliances were collated for each retrieved study. From 6796 potentially eligible studies, 90 were considered for this systematic review. Four were RCTs which were graded with the Cochrane risk of bias tool. Three were assessed as having low and one as having moderate risk of bias. The other 86studies were graded with the modified Downs and Black tool which revealed that 47 showed low, 38 low/moderate, and 1amoderate risk of bias. The most commonly assessed appliances were the Twin Block which was used on 783 patients, the Frankel appliance on 573, the Herbst appliance on 530, the Activator on 449, the Forsus appliance on 394, the MARA appliance on 202, and the Bionator on 133, for atotal of 3064 treated patients. This systematic review provides conclusive evidence that the Twin Block appliance demonstrated the highest coefficient of efficiency among all the evaluated appliances (0.46 mm/month), while the Forsus fatigue resistant device (FFRD) had the highest coefficient of efficiency among the fixed functional appliances (0.41 mm/month).

Objective - Our systemic review aimed to evaluate the efficacy of applying Herbst and Twin Block appliances in the treatment of Class II malocclusion among children. Materials and Methods - A systematic review following PRISMA guidelines was conducted to compare Twin Block and Herbst appliances in treating Class II malocclusion in growing children (12–18 years). Studies were identified through PubMed, ScienceDirect, Google Scholar, and Cochrane Library (2000–2024) using the terms: Twin Block OR Herbst Appliance AND Skeletal, Dental, Soft Tissue changes. Eligible studies included RCTs, CCTs, and cohort studies in English. Primary outcome assessed was skeletal changes; secondary outcomes included dental and soft tissue effects. Study quality was scored (0–9) based on design, sample details, error analysis, and statistics, and categorized as high, medium, or low quality. Results - Eighteen studies met the inclusion criteria from an initial yield of 4306 records across four databases. The selected studies evaluated skeletal, dental, and soft tissue changes in growing patients treated with Twin Block or Herbst appliances for Class II malocclusion. Twin Block therapy predominantly demonstrated mandibular advancement and correction of molar relationship, with variable improvements in facial aesthetics. Herbst appliance use was associated with increased mandibular ramal height and similar skeletal corrections. However, direct comparisons were limited due to heterogeneity in study designs and outcome measures. Quality assessment classified nine studies as high quality and nine as medium. Although all studies had adequate sample sizes, only eight were randomized controlled trials, and comprehensive error analysis was reported in a minority. Statistical methods were adequate in most studies, though several relied solely on descriptive analysis. Conclusion - Both Twin Block and Herbst appliances are effective in correcting Class II malocclusion through favourable skeletal, dental, and soft tissue modifications. While Herbst offers greater mandibular advancement due to its fixed design and superior compliance, Twin Block is associated with enhanced skeletal changes and improved facial aesthetics. Overjet reduction is comparable, though incisor proclination is more pronounced with the Herbst. Despite faster initial correction with the Herbst, overall treatment durations are similar. Longterm stability, gender-specific responses, and retention protocols warrant further investigation

The aim of this retrospective study was to compare the effects of the Twin block and Herbst appliances on the mandibular trabecular pattern using fractal dimension analysis (FDA) of panoramic radiographs (PRs). The PRs of 50 subjects with skeletal Class II malocclusion who underwent the Twin block (T-group, average age: 11.63±0.87; 25 girls, 25 boys), 50 subjects with skeletal Class II malocclusion who underwent the Herbst (H-group, average age: 11.72±0.91; 27 girls, 23 boys), and 50 controls (C-group average age: 11.67±0.83; 24 girls, 26 boys) were selected. The condyle, corpus, and angulus regions of all groups in the mandible were examined using FDA. The condylar region (p≤0.001) and corpus mandible in the treatment groups (T-group: right, p≤0.05, left, p≤0.01; H-group: p≤0.05), as well as the left and right condylar region (p≤0.001) and left corpus mandible (p≤0.05) in the C-group, all indicated substantial increases in FDA between T0 and T1. Inter-group comparisons indicated that the T-group had greater variances in the condyle (p≤0.001) compared to the H group. As the findings revealed both Twin block and Herbst appliances not only contributed to the dentoalveolar structure but also provided remodeling of the mandibular trabecular structure. Consequently, the null hypothesis was rejected.

ObjectivesHerbst appliance treatment results in posterior airway space (PAS) increase. The published data, however, is based on rather small samples and shows large inter-individual variation. Therefore, the current aim was to investigate PAS changes during and after Herbst plus subsequent multibracket appliance (MBA) treatment in a retrospective cohort study and to search for possible pre-treatment influencing factors.Materials and methods503 former Class II:1 patients (overjet = 7.8 ± 2.4 mm, ANB angle = 5.0 ± 2.1°) who had undergone treatment at 13.8 ± 3.4 years (Department for Orthodontics, University of Giessen, Germany). Cephalograms from before (T0), after 24.9 ± 9.2 months of treatment (T1) and 26.1 ± 8.0 months after treatment (T2) were analysed for PAS changes (area-size and linear distances p, t, pC2, pC3, pC4. In addition, possible influencing pre-treatment characteristics were evaluated: overjet, ANB angle, Wits appraisal, ML/NSL angle, ArGoGn angle, age and skeletal maturity.ResultsOn average, the PAS area increased by 23% during Herbst-MBA treatment (T1-T0) and remained constant (± 0%) thereafter (T2-T1). All linear distances also increased (6–19%) during T1-T0 and showed further increase (1–7%) during T2-T1. For all variables a large inter-individual variation existed. With regard to possible influencing factors on PAS changes, significant associations were observed for pre-treatment age and Wits appraisal of the patients.ConclusionsPAS increases during Herbst-MBA treatment. For none of the assessed variables, relapse occurred afterwards. Young age and a large Wits appraisal were determined to be beneficial for PAS enlargement.Clinical relevanceHerbst-MBA treatment seems to have a positive effect in the majority of Class II patients with reduced PAS.