Proclination Of Lower Incisors Research Articles

Association of Mandibular Incisor Proclination and Mandibular Arch Widths with The Levelling of Curve of Spee

Background: In this study, we aimed to determine the changes in mandibular incisor proclination and mandibular arch widths after leveling the curve of Spee (COS). Methods: Patients included in this quasi-experimental study were scheduled for fixed orthodontic treatment with a non-extraction therapy in the mandibular arch, no posterior crowding, eruption of all mandibular teeth except third molars, no spacing and Little’s irregularity index greater than 2. The COS depth and mandibular arch widths (inter-canine and inter-molar widths) were measured on plaster casts and recorded in millimeters. Mandibular incisors inclinations were measured on a cephalometric radiograph according to the incisor mandibular plane angel (IMPA) and lower incisor to NB (L1) angle. The pre-treatment and post-treatment values were compared using paired sample T-test. Pearson correlation was used to analyze the association between COS changes and other variables. P-value <0.05 was considered statistically significant. Results: A total of 58 subjects with an average age of 25.10±6.81 years participated in this study. COS depth values significantly reduced after treatment (2.34±0.78mm vs 1.75±0.56mm), (P<0.001). Average IMPA and L1-NB values significantly increased following COS flattening (P<0.001). Mandibular inter-canine and inter-molar widths also showed significant increase after treatment (P<0.001). Pearson’s correlation revealed a significant and inverse correlation between COS changes and mandibular arch width and mandibular incisor proclination values (P<0.001 for both). Patient’s age and gender did not have a significant effect on COS depth. Conclusion: Flattening of COS leads to an increase in lower incisor proclination and mandibular arch width.

Correction of Anterior Cross Bite in Mixed Dentition period using Quadhelix and Catalans appliance - A Case Report

The case report addresses the challenge of correcting anterior cross bite in mixed dentition period. It emphasizes the complexity of treating skeletal Class III malocclusion, especially in young patients, and highlights the importance of choosing appropriate orthodontic appliances for effective treatment. The subject of the case report is a 9-year-old girl, MK, who presented with a prognathic profile, upper and lower incisor proclination, and bimaxillary protrusion. The treatment plan was multifaceted, incorporating oral prophylaxis, fluoride application, indirect pulp capping, and strategic extractions. Key appliances used were the Quadhelix and Catalans appliances, supplemented by a lower inclined plane, removable Jack Screw appliance with a posterior bite plane, and a Nance Palatal Arch space maintainer. The report meticulously documents the treatment progression with detailed photographs and radiographs, capturing changes at 10 days, 24 days, and 3.5 months intervals. The case report concludes that the use of Quadhelix and Catalans appliances, in conjunction with a comprehensive treatment plan, effectively corrected the anterior crossbite in this patient. The treatment led to significant dental and skeletal improvements, as evidenced by the post-treatment cephalometric analysis. This case underscores the effectiveness of these appliances in pediatric orthodontic cases with similar presentations. Bangladesh Journal of Medical Science Vol.23 (Special Issue) 2024 p.S43-S47

Modified Essix Twin Block Appliance: Successful Application in Adult Patient- A Case Report

Twin-block appliance has proven its efficiency in adolescents. William Clark has given this appliance to non-growing patients also. Here we gave the appliance to a 20-year-old male. Appliance fabrication was done with a thermoformed sheet and acrylic. With this appliance, we achieved dento-alveolar and skeletal changes in a 20-year-old male patient. Generally, twin block has disadvantages like lower incisor proclination, poor periodontal health issues, and patient hesitance to wear the appliance. In this design, we have overcome the issues mentioned above. Soft tissue profile has also improved. Total treatment for appliance therapy was 8 months.

Cephalometric and digital model analysis of dentoskeletal effects of infrazygomatic miniscrew vs. Essix- anchored Carriere Motion appliance for distalization of maxillary buccal segment: a randomized clinical trial

Trial designParallel.ObjectiveTo compare skeletally anchored Carriere Motion appliance (CMA) for distalization of the maxillary buccal segment vs. Essix anchored CMA.MethodsThirty-two class II malocclusion patients were randomly allocated into two equal groups. One group was treated with infrazygomatic (IZC) miniscrew- anchored CMA (IZCG) and the other group treated with Essix retainer- anchored CMA (EXG). Two lateral cephalograms and two digital models for upper and lower arches were taken for each patient: immediately before intervention and after distalization had been completed.ResultsDistalization period was not significantly different between the two groups. In contrast to EXG, IZCG showed insignificant difference in ANB, lower incisor proclination, and mesial movement of the lower first molar. There was significant rotation with distal movement of maxillary canine and first molar in both groups.ConclusionIZC anchored CMA could eliminate the side effects of class II elastics regarding lower incisor proclination, mesial movement lower molars with a more significant amount of distalization of the maxillary buccal segment but with significant molar rotation.Trial registrationThe ClinicalTrials.gov Protocol Registration and Results System (PRS) has this RCT registered as (NCT05499221) on 12/08/2022.

Evaluation of Clinical Efficacy Between Forsus and Advansync Fixed Functional Appliance for the Treatment of Skeletal Class II Malocclusion Using 3D Cone Beam Computed Tomography (CBCT): A Prospective Randomized Clinical Trial.

The objective is to assess and compare whether AdvanSync gives better skeletal, dental, and soft tissue outcomes than Forsus fixed functional appliance in post-pubertal skeletal Class II malocclusion patients. A prospective study was conducted using 3D-CBCT of patients taken before and after fixed functional appliance therapy. The sample consisted of 16 patientsdivided into two groups: Group 1 was treated with Forsus and group 2 with AdvanSync appliance. All subjects were in their post-pubertal growth phase. Treatment changes were evaluated between the study groups using 12 angular and 14 linear parameters. The data were subjected to statistical analysis. Statistically significant changes in SNB(P:0.04) and ANB (P:0.01) in Forsus appliance andAdvanSync (SNB, P:008), (ANB, P: <0.001)were found between the pre and post-fixed functional appliance protocol. The effective mandibular length increased in both groups Forsus(P-value: 0.01) and AdvanSync (P-value: 0.01). Group 1 resulted in lower incisor proclination and intrusion, a reduction in an overbite, whereas group 2 resulted in lower incisor proclination, upper incisor extrusion, and retroclination. Both groups showed significant improvement in the molar relation and overjet. An increase in the total facial convexity was shown in group 1; group 2 showed an increase in the facial convexity and total facial convexity. There was no statistically significant differencebetween the effects of the Forsus and Advansync appliance groups in the post-fixed functional period. Both groups presented similar results. Forsus and Advansync appliances are effective with similar results in normalizing skeletal Class II malocclusion in post-pubertal patients. There was no statistically significant difference between the groups using Forsus or AdvanSync. Thechanges were minimal - mandibular skeletal effects, majorly dentoalveolar effects, and mild soft tissue effects.

Microscrew Assisted Twin-Block Appliance Therapy of a Skeletal Class II Adolescent Patient with a High Mandibular Plane Angle

This case report describes an orthopedic and orthodontic treatment of a young female patient who had skeletal Class II malocclusion with mandibular deficiency and vertical growth tendency. Favorable anterior growth of the mandible was acquired by using Twin-block appliance. In application of the Twin-block, it was modified using microscrew to reduce the side effects, like lower incisor proclination and upper incisor reclination, which reduces the potential of achieving maximum skeletal effects. The aim of this case report is to present an idea when using the Twin-block appliance. By this method, the proclination of the lower incisors and the reclination of the maxillary anterior teeth could be prevented. Moreover, the vertical growth of the maxillary dentition could be inhibited by using intraoral elastics between the microscrews and buttons on the Twin-block. This idea may be useful in the treatment of the growing skeletal Class II patients with deficient mandible.

Non-surgical Treatment of a Late Adolescent Patient with Skeletal Class II Malocclusion Using Clear Aligners: A Case Report

Background/Introduction: There are a variety of treatment modalities for orthodontic treatment of patients with skeletal Class II malocclusions in late adolescence. These treatment modalities may include surgical intervention, camouflage treatment, functional appliances, extraction of teeth, and/or Class II elastics mechanics. Most Class II mechanics produce retroclination of the upper incisors and proclination of lower incisors. These dentoalveolar effects limit the possibility for forward mandibular projection/growth, hence minimizing skeletal improvement. Case Presentation: To present a unique case report that was treated with a new perspective in maximizing skeletal improvement in a late adolescent male with skeletal Class II malocclusion and deep overbite. A 15-year-old male presented with a skeletal Class II pattern due to mandibular retrognathism was treated with non-extraction, non-surgical technique using clear aligners in two phases. Phase 1 was designed to decompensate the compensated inclination of his anterior teeth, and phase II was planned to correct his skeletal and dental Class II malocclusion/mal relation. Results: Maxillary incisors decompensation of the inclination of the upper and lower incisors and posterior teeth intrusion allowed forward mandibular projection that led to skeletal and dental correction of his malocclusion and improvement of his chin forward projection. Conclusion: This case report shows successful treatment of a Class II malocclusion in alate adolescent male. This method could perhaps be used for similar cases, avoiding the need to extract teeth or include surgical intervention.

Elastodontic treatment with oral bio-activators in young children.

Elastodontic therapy can correct bad oral habits and malocclusions in young patients by guiding jaw growth, eliminating functional disorders, and improving tooth position. The aim of this study was to assess the effects of bio-activator therapy on the presence of atypical swallowing with tongue thrust in growing patients. A retrospective study was conducted. Data regarding the early orthodontic treatment of 40 consecutive patients with atypical swallowing and tongue thrust (23 males and 17 females) were assembled from January 2019 to January 2020. All patients (≥7 and ≤15 years of age) were monitored for 1 year in a private practice in Isernia, Italy. The mean age at commencement of orthodontic treatment was 8.5 years (range=7.1-14.9 years), and the mean total duration of therapy was 1 year (range=11 months-1 year). Final lateral radiographs demonstrated a mean of improvement of 8° for upper and lower incisor proclination (I/SN) and 3.5° for incisor mandibular plane angle (IMPA) in 36 patients, and 5° of I/SN and 2° of IMPA in the remaining 4 children after 1 year of treatment. Bad oral habits in younger patients must not be ignored. The duration of treatment can differ depending on the severity of the open bite and the patient's cooperation. This study demonstrates the short-term efficacy of these myofunctional appliances in the treatment of atypical swallowing. In order to quickly eliminate factors which endanger healthy development of dento-skeletal structure, it is important to closely monitor patients during their development phase.

An Umbrella Review of Systematic Reviews With or Without Meta-Analysis Assessing Treatment Outcomes and Efficiency of Self-Ligating Brackets

Introduction Self-ligating bracket systems are popular and seem to demonstrate lesser friction, allowing tooth movement without exerting unwanted forces on surrounding structures. This umbrella review aimed to compare self-ligating and conventional bracket systems for treatment efficiency. Methods An electronic search in 8 databases was performed for literature published between January 1, 1990, and October 1, 2021, with manual hand-searching of references of retrieved articles. Quality assessment was performed using the risk of bias in a systematic tool by 2 independent reviewers. Data were extracted using a prepiloted form (Joanna Briggs Institute) for evidence synthesis. Corrected covered area was calculated to quantify study overlaps across systematic reviews with or without meta-analysis. Results 605 articles were retrieved, of which 16 were selected. Most included studies had a low risk of bias, except for 6 that showed an unclear risk of bias. Data analysis revealed a reduction in lower incisor proclination, bacterial accumulation, and oral malodor using self-ligating appliances. Conclusions Self-ligating systems reduce mandibular incisor proclination, bacterial accumulation, external apical root resorption, chairside time, and oral malodor. No other differences could be demonstrated in comparison with conventional appliance systems.

Does Early Treatment Improve Clinical Outcome of Class II Patients? A Retrospective Study.

The present study was carried out to evaluate the benefits from one-phase Class II Early Treatment (ET) using extraoral forces and functional appliances but without intermaxillary forces and eventual lower leeway space preservation compared to two-phase Class II Late Treatment (LT) with the need for extractions and full fixed appliances as well as lower incisor proclination. The ET group (n = 239, 115 M, 124 F, mean age 10.6 ± 1.2 years), with first premolars not in contact and the second deciduous lower molars preserved, was compared to the LT group (n = 288, 137 M, 151 F, mean age 12.4 ± 1.5 years). The ET group was first treated with headgears, growth guide appliances, or Teuscher activators and, in borderline crowding cases, with lower space maintenance by a lingual arch, lip bumper, or fixed utility arch. The LT group and the second phase of ET were treated with full fixed appliances including intermaxillary forces such as Class II elastics or noncompliance devices; headgear and a growth guide appliance were also used. Cephalograms and plaster models were taken before (T1) and after treatment (T2) to calculate cephalometric changes and space balance discrepancies. The differences between T1 and T2 were analyzed by a t-test for normally distributed data and by the Mann–Whitney Test for nonnormally distributed data at a level of p < 0.05. The groups were defined as statistically homogeneous at T1. A statistical analysis showed that the ET group (mean treatment time 35.3 ± 13.3 months) was significantly associated with a 22.2% lower extraction rate, 15.9% less need for a full fixed appliance, and more than 5° less incisor proclination in the nonextraction cases compared to the LT group (mean treatment time 25.9 ± 8.1 months); treatment time significantly increased in the ET group compared to the LT group. Early Class II treatment resulted in a significant treatment effort reduction in more than one third of the patients and less lower incisor proclination, even if it clinically increased treatment time.

Orthodontic treatment for crowded teeth in children.

Orthodontic treatment for crowded teeth in children.

The efficiency of mandibular mini-implants in reducing adverse effects of class II elastics in adolescent female patients: a single blinded, randomized controlled trial

BackgroundExcessive proclination of lower incisors and other undesirable consequences usually result from the use of class II elastics during orthodontic treatment. The purpose of this study was to attempt to limit the adverse effects of class II elastics by the use of mini implants placed in the mandibular arch in adolescent class II female patients.MethodsThe sample comprised 28 patients, (a mean age of 15.66 ± 2 years for intervention group and 15.1 ± 2.2 years for conventional group) with one-fourth or one-half unit class II canine relationship. The sample was divided into two equal groups. Randomization was carried out by a computer sequence generator with a 1:1 allocation ratio. In the intervention group, the mini implants were inserted between the lower second premolar and first molar, while the conventional group underwent regular class II elastics therapy. The active elastics treatment time was 8 months for both groups. Results were assessed by measurements from pre- and post-elastics lateral cephalometric radiographs.ResultsThe change in L1 inclination (0.97 ± 0.92°) and L1 AP position (0.31 ± 0.63 mm) did not show a statistically significant difference between the two groups, but a statistically significant difference was found in the U1 retroclination (5.23 ± 1.92°) and U1 distal movement (4.05 ± 1.4 mm) [P ˂ 0.001] and [P ˂ 0.05] respectively in favor of the intervention group.ConclusionMini-implants in conjunction with class II elastics had no skeletal effect, mainly dentoalveolar and it did not prevent the proclination of lower incisors. There was more distal movement in the upper incisors in the skeletal anchorage group which helped in enhancing the camouflaging of class II malocclusion.Trial registrationTrial registered “FUE.REC (10)/10-2018” at the FUE registration council for clinical trials/IOP Orthodontic Program October 2018.

A comparative study between the effect of reverse curve of Spee archwires and anterior bite turbos in the treatment of deep overbite cases.

To compare deep overbite treatment using 0.016 × 0.022 nickel-titanium lower reverse curve of Spee archwire (LRCA) or metal anterior bite turbos (ABTs). 48 patients with deep overbite malocclusion were randomly allocated into two groups. Group I (age = 18.4 ± 2.8 years, overbite = 5.8 ± 0.6 mm) was treated with LRCA, while Group II (age = 18.2 ± 3.1 years, overbite = 5.2 ± 0.4 mm) was treated with ABTs bonded to the palatal surface of the upper central incisors. Two cephalograms were taken for each patient, at post-alignment stage (T1) and post-leveling stage (T2). The primary outcomes were the anteroposterior and vertical changes of the lower teeth. The secondary outcomes were the effect on upper incisor inclination and the vertical linear changes of upper teeth, to assess the sagittal and vertical skeletal changes, and to compare the duration of overbite correction. 42 of the 48 patients recruited completed the study (21 in each group). At T2, the lower incisors proclined more in Group I (P ≤ .001). Both lower second molars (P ≤ .001) and lower first molars (P = .001) tipped more distally, while the lower first premolar tipped more mesially, in Group I (P < .05). All cusps of both lower molars showed more extrusion in Group II (P < .05) except for the mesial cusp of lower second molars (P = .095). The duration of overbite correction was shorter using the ABTs by 1.7 months (4.85 ± 1.56 and 3.15 ± 0.93 months for Group I and Group II, respectively). LRCA causes lower incisor proclination with distal tipping of lower molars, while ABTs result in lower posterior tooth extrusion.

Treatment effects of Carriere Motion Appliance on patients with class II malocclusion: A systematic review and meta-analysis

To investigate the treatment effects of Carriere Motion Appliance (CMA) on class II patients. A comprehensive electronic search was performed in PubMed, Scopus, Web of science, ScienceDirect, ProQuest (dissertation and thesis), Google Scholar and ClinicalTrials.gov. All types of clinical trials that contained at least pre- and post-treatment measures of patients treated by CMA were included in this systematic review and meta-analysis. The risk of bias was assessed for all included studies. The considered outcomes were the skeletal, dento-alveolar, soft tissues, temporomandibular joint and airway changes, electromyographic activity and stability. Sixteen studies were included in this systematic review and meta-analysis. The absence of randomized controlled trials which could induce confounding and selection of participant bias is considered the main risk of bias affecting the available studies. Regarding the skeletal changes, no significant effects were appreciated (changes in SNB angle; SMD=-0.13; 95% CI (-0.57, 0.31); P=0.58. Changes in SN-MP; SMD=-0.11; 95% CI (-0.54, 0.33); P=0.64). With respect to the dento-alveolar changes, an increased lower incisor's proclination (L1-MP) was observed; SMD=-0.69; 95% CI (-1.14, -0.24); P=0.003. CMA caused an increase in the airway volume, an increase in the masseter and temporalis muscles activities and a minor relapse of malocclusion after 4-years of follow-up. The results should be taken with caution because only secondary level of evidence was found. The CMA used for the treatment of class II malocclusion did not cause skeletal changes; however, largely dento-alveolar effects were noticed. Prospective randomized clinical trials are highly recommended.

Treatment of mild Class II malocclusion in growing patients with clear aligners versus fixed multibracket therapy: A retrospective study

ObjectiveTo compare the dental and skeletal effects of intermaxillary elastics on the correction of mild Angle's Class II division 1 malocclusion with clear aligner treatment (CA) versus fixed multibracket (FMB) in growing patients.Settings and sample populationThe study sample consisted of 49 consecutively patients (mean age ± SD 12.9 ± 1.7 years), 32 females and 17 males referred from the School of Orthodontics of the University of Bratislava Comenius (Slovakia). All patients were treated with a non‐extraction orthodontic treatment, 25 with FMB and 24 with CA.MethodsThe cephalometric analysis was performed at the beginning (T0) and the end of the treatment (T1). The t test for unpaired data was carried out to compare cephalometric values at T0 and changes at T1‐T0 between the two groups. The level of significance was set as P < .0035.ResultsThe two groups showed no statistically significant differences (ANPg = −0.1°; P = .762) in the correction of the sagittal intermaxillary relation. The analysis of vertical skeletal changes showed no statistically significant effects on mandibular inclination (SN/MP = 0.1°; P = .840). The two treatments had a statistically significant and clinically relevant difference in controlling the inclination of the lower incisors (L1/GoGn = 4.8°, CAG = −0.5°± 3.9°; FMB = 4.3°± 5.8°; P < .001).ConclusionsClass II elastics combined with CA and FMB produce a similar correction on sagittal discrepancies in growing patients. CA presented a better control in the proclination of the lower incisors. CA and elastics might be a good alternative in the correction of mild Class II malocclusion in cases where a proclination of lower incisors is unwanted.

Tratamento de Classe II utilizando Propulsor mandibular PowerScope II: Relato de caso clínico

A Classe II de Angle, além de ser uma das más oclusões mais procuradas para tratamento, é também um grande desafio para os ortodontistas. Quando um paciente se apresenta com deficiência mandibular e ainda em fase de crescimento, os aparelhos funcionais, geralmente, são escolhidos para a correção deste problema. Porém, em algumas situações, a falta de colaboração do paciente no uso destes aparelhos, especialmente os removíveis, podem comprometer o resultado do tratamento ortodôntico. Com a evolução dos aparelhos propulsores mandibulares, vários modelos funcionais começaram a surgir no mercado e, dentre estes, o PowerScope, um propulsor fixo híbrido. Entretanto, um dos efeitos esperados de todos os propulsores, sejam eles removíveis ou fixos, além da remodelação dento-alveolar, é a inclinação labial excessiva dos incisivos inferiores. Desta forma, o objetivo desse estudo foi demonstrar o uso do PowerScope II, na correção de Classe II de Angle em um paciente de 12 anos com deficiência mandibular, braquifacial e com incisivos superiores e inferiores vestibularizados. Após planejamento detalhado, optou-se por utilizar aparatologia fixa com prescrição Roth 0,022”, seguida pelo PowerScope II e mini parafusos inferiores bilaterais, como forma de ancoragem, para conter a vestibularização excessiva dos incisivos inferiores. Ao fim do tratamento o paciente manteve o perfil convexo com correção da má oclusão pela compensação dentoalveolar e conseguiu um bom controle de inclinação dos incisivos inferiores. Assim, pode-se concluir que a utilização desse dispositivo associado aos mini parafusos de ancoragem permitem uma abordagem conservadora em tratamentos de Classe II.

Evaluation of Tweed’s Facial Triangle among Students in Lagos, Nigeria

Introduction: The advent of cephalometric analysis has aided orthodontic diagnostic procedures, while the Tweed’s facial triangle which is a type of cephalometric analysis has complemented routine orthodontic treatment planning. This aim of this study was to evaluate Tweed’s facial triangle among a selected Nigerian population with normal occlusion.&#x0D; Materials &amp; Method: A sample of 100 subjects, selected by multistage sampling from three schools in Ikeja local government, Lagos State had lateral cephalometric radiographs taken. The final sample analysis of the radiographs was 84. The error of the cephalometric method was assessed using the intra-class correlation co-efficient. The Tweed’s facial triangle was analyzed on the cephalometric radiographs and comparison between this Nigerian population and Tweed’s Caucasian cohort was carried out.&#x0D; Result: Out of the 84 subjects, 41(48.8%) were males and 43(51.2%) females. This study reported mean values of 23.26° ± 4.78° for FMA, 54.08° ± 5.11° for FMIA and 103.47° ± 6.26° for IMPA. Females had higher FMIA and IMPA values compared to males which was statistically significant for FMIA. The FMA was higher in males with a statistically significant difference between genders. The results suggest increased proclination of lower incisors in this Nigerian population compared to Tweed’s Caucasian population.&#x0D; Conclusion: The mean values for Tweed’s facial triangle in this Nigerian population were significantly different from that obtained by Tweed. Orthodontists should aim at achieving these values when analyzing cephalometric radiographs using Tweed’s facial triangle in Nigerians. This will further aid proper diagnosis, treatment planning with or without extractions and planning of retention after orthodontic treatment.

Gambaran Hasil Analisis Sefalometri Pada Pasien Ras Deutro Melayu Usia 8-12 Tahun Menggunakan Analisis Ricketts

Background: Cephalometric analysis is one of the supporting tools in establishing a correct diagnosis. From the various methods of cephalometric analysis, one that used is the analysis of Ricketts. This Ricketts analysis has a method for determining the position of facial convexity, dental position and face profile. This study was thus carried out to describe the value of cephalometric measurements in patients with Deutro Melayu race aged 8-12 years using Ricketts analysis. Method: This type of research is a descriptive observational cross sectional design. Samples were taken in the form of secondary data, namely cephalograms from orthodontic patients at RSGM FKG Usakti in January 2018 to December 2018. The analysis was carried out by measuring 8 Ricketts analysis parameters, namely: facial axis, facial depth, mandibular plane, convexity of point A, lower incisor to A-Pog, upper molar to PtV, lower incisor to A-Pog, lower lip to aesthetic lines. Result: Based on Ricketts analysis, the cephalometric mean value of RSGM FKG Usakti orthodontic patients was facial axis of 87,8°; facial depth of 85,6°; mandibular plane of 31°; convexity of point A 3,5 mm; the lower incisor distance to A-Pog of 3,0 mm; upper molar to PtV of 7,8 mm; the lower incisor angle to A-Pog of 23,5°; lower lip to aesthetic lines of 1,9 mm. Conclusions: Deutro Malay Race has a skeletal class 1 with a tendency towards lower incisor proclination and mild protusive lower lips.

Angle classII correction: stepwise mandibular advancement or bite jumping? : Asystematic review and meta-analysis of skeletal, dental and condylar effects.

There is no consensus regarding which mode of activation or mandibular advancement (stepwise [SW] or maximum bite-jumping [BJ]) of fixed or removable functional appliances (FFA; RFA) for correction of Angle classII malocclusion is advantageous to produce dental, skeletal or condylar effects and has the lowest rate of undesired dental or technical side-effects. A systematic search was conducted up to Oct. 20, 2019 in the MEDLINE, EMBASE, Scopus, Central Cochrane Library, and BBO databases. Included were preadolescent, adolescent, and adult humans with initial (pretreatment) Angle class II malocclusion, without further restriction. The intervention group was composed of subjects treated with FFA or RFA in SW mandibular advancement; the control group received BJ advancement. Search terms included prospective randomized and nonrandomized trials in English, German, Spanish, and Portuguese with the primary outcomes of skeletal and dental class II correction, effects on condylar growth, lower incisor proclination, overjet and overbite reduction. The risk of bias (ROB) was assessed using the Cochrane Collaboration's ROB2 tool. Mean differences were calculated and pooled by a meta-analysis using a random effects model. Data from five randomized controlled trials (RCT) with 401 participants (mean age 13.84years; SD 1.53) were included; 331 derived from four studies were included in the meta-analysis. The ROB in the selected articles was high. We detected aslightly increased reduction of the ANB (mean difference [MD] -0.95°, 95% confidence interval [CI] -1.80 to -0.10°; I2 = 72%) that may be attributed to aslightly more pronounced increase of the SNB angle in SW-advanced mandibles (MD 0.27°; 95% CI -0.47 to 1.00°; I2 = 38%). SW advancement tended to reduce the undesired side effect of lower incisor proclination (MD = -1.59°; 95% CI -3.98 to 0.8°; I2 = 0%), indicating more pronounced mandibular incisor changes with bite-jumping advancement. There is weak evidence indicating aslightly increased reduction of the ANB and less lower incisor proclination with SW advancement compared to BJ, but the clinical relevance is debatable due to the small overall magnitude and small number of high-quality papers. Prospero #CRD42017075469 (www.crd.york.ac.uk/prospero).

Differential skeletal and dental effects after orthodontic treatment with bite jumping appliance or activator: a retrospective cephalometric study.

The aim of this retrospective cephalometric study was to compare treatment outcomes with "bite jumping appliance" (BJA) or Andresen-Häupl type activator. It especially focused on skeletal and dental structures in patients with class II malocclusion. The study hypothesis was that differences in treatment-related changes would occur between patients treated with BJA or activator. Pre- and posttreatment lateral cephalograms of 73 patients with a class II malocclusion were analyzed. Thirty-seven patients (22 females, 15 males) received treatment with a BJA (pretreatment age 11.1 ± 1.07years) and 36 patients (20 females, 16 males) with an activator (pretreatment age 11.3 ± 1.12years). Treatment time was 14.0 ± 1.8months with BJA and 12.0 ± 2.0months with activator. Paired t tests were used for intragroup and t tests for independent samples for intergroup comparisons. Results were considered statistically significant at P < 0.05. The comparison of sagittal and vertical skeletal changes after BJA and activator treatment did not reveal significant differences. Significant changes occurred for lower incisor inclination (P = 0.0367) and overjet (P = 0.0125) only. The reduction of overjet and proclination of lower incisors were more pronounced in BJA patients. Both "bite jumping appliance" (BJA) and Andresen-Häupl type activator were able to improve the occlusion of patients with a class II malocclusion. Dental effects were more pronounced for the BJA. Marked lower incisor proclination contributed significantly to overjet correction in BJA patients. This ought to be respected when choosing a removable functional appliance for patients whose lower incisors are already proclined prior to treatment.