Long-term effects of functional appliances in treated versus untreated patients with Class II malocclusion: A systematic review and meta-analysis

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

AIM

Two-phase treatment for children with Class II malocclusion with several functional appliances is still performed by many orthodontists, while the Activator and the Bionator appliances are two of the most popular ones. Aim of this study was to compare the skeletal and dentoalveolar effects of treatment with these two appliances.

METHODS

Class II children treated with Activator or Bionator in the first phase, followed by a phase of fixed appliances were included. Skeletal and dentoalveolar parameters were assessed from lateral cephalograms and analysed with linear regressions at 5%.

RESULTS

A total of 89 patients (mean age 10.0 years; 47% female) were included. During the first phase, Bionator increased less the SNB (difference in mean treatment-induced changes [MD] -0.7°; 95% confidence interval [CI] -1.3 to -0.2°; P=0.01) and decreased less the ANB angle (MD 0.6°; 95% CI 0 to 1.1°; P=0.03) compared to Activator. Activator slightly increased the facial axis and Bionator reduced it (MD -1.6°; 95% CI -2.3 to -0.8°; P<0.001). Compared to Activator, the Bionator retroclined more the upper incisors (MD -2.4°; 95% CI -4.6 to -0.2°; P=0.03) and increased more the interincisal angle (MD 2.9°; 95% CI 0.5 to 5.4°; P=0.02). After the second phase (6.2 years after baseline), the only differences were a reduced facial axis (MD -1.3°; 95% CI -2.2 to -0.3°; P=0.008) and an increased maxillary rotation (MD 0.9°; 95% CI 0 to 1.8°; P=0.04) with Bionator compared to Activator.

CONCLUSION

Similar dentoalveolar effects were seen overall with two-phase treatment with either appliance, with Bionator being associated with more vertical increase compared to Activator.

Mandibular Endochondral Growth Is Specifically Augmented by Nutritional Supplementation with Myo-Inositol Even in Rabbits

Mandibular retrognathism occurs by insufficient mandibular growth and causes several issues, such as respiratory difficulty and diminished masticatory function. At present, functional orthodontic appliances are used for stimulating mandibular growth in pediatric cases. However, the effectiveness of functional appliances is not always stable in daily practices. A more effective, reliable, and safer therapeutic method for mandibular growth promotion would be helpful for growing mandibular retrognathism patients. As we previously discovered that nutritional supplementation of myo-inositol in growing mice specifically increases mandibular endochondral growth, we performed preclinical animal experiments in rabbits in this study. Briefly, six-week-old male Japanese white rabbits were fed with or without myo-inositol supplementation in laboratory chow until 25 weeks old, and 3D image analysis using micro CT data and histological examinations was done. Myo-inositol had no systemic effect, such as femur length, though myo-inositol specifically augmented the mandibular growth. Myo-inositol increased the thickness of mandibular condylar cartilage. We discovered that the nutritional supplementation of myo-inositol during the growth period specifically augmented mandibular growth without any systemic influence, even in rabbits. Our results suggest the possibility of clinical use of myo-inositol for augmentation of the mandibular growth in growing mandibular retrognathism patients in the future.

Effect of functional appliances on sleep-disordered breathing in Class II division 1 malocclusion children: Randomized controlled trial

OBJECTIVES

A randomized controlled trial was undertaken to investigate the orthopaedic effect of functional appliances on the pharyngeal airway space and nocturnal breathing of children with skeletal class II due to mandibular retrusion.

MATERIALS AND METHODS

Forty patients were randomized into a 1:1 ratio study (Twin block) group and a control (fixed appliance) group. Each group included equal numbers of boys and girls. Diagnosis with sleep-disordered breathing was not an inclusion criterion. The duration of the trial was 12 months (T0 - T12). Eligibility criteria included skeletal Class II division 1 malocclusion with mandibular retrognathism, SNA ≥82, SNB ≤78, ANB ≥4, overjet ≥6 mm, and patients in circumpubertal stage CVM2 and CVM3. The main outcomes were pharyngeal airway volume, oxygen desaturation index (ODI), and maximum expiratory pressure (MEP), while the secondary outcomes were skeletal and dental changes of the maxilla and mandible. Randomization was accomplished with random blocks of 20 patients with allocation concealed in sequentially numbered, opaque, and sealed envelopes. Blinding was only applicable for data analysis of radiographic measurements and data extracted from the pulse oximeter.

RESULTS

The mean age of the patients was 10 ± 1.5 and 10 ± 1.2 at (T0) for the Twin Block and the control groups, respectively. The changes in the oropharyngeal (2.66 cc and 0.056; P = .03) and nasopharyngeal (1.3 cc and 0.84; P = .053) airway volumes for the Twin block and control groups, respectively, were significantly different for the oropharynx. There was a significant decrease in ODI by [median -3.55 (-5.05 to 0.50); P ≤ .001] and a significant increase [median 45 (0.0-110); P ≤ .001] in MEP for the Twin block group. A significant inverse correlation (r = -.589; P = .006) could be found between the total volume of the oropharynx and ODI. No serious harm was observed.

CONCLUSIONS

The Twin block group showed significant change in oropharyngeal airway volume and improvement of nocturnal breathing.

REGISTRATION

This trial was registered at https://www.

CLINICALTRIALS

gov, registration number NCT04255511.

Orthodontic Management of Skeletal Class II Malocclusion with the Invisalign Mandibular Advancement Feature Appliance: A Case Report and Review of the Literature

The treatment of Class II malocclusion due to mandibular retrognathia is one of the most common challenges met in orthodontic practice. When it comes to a growing patient, functional appliances are the optimal way to achieve growth modification by enhancing mandibular growth. Clear aligners have been part of the orthodontic treatment for several decades but until recently they were only used to correct mild malocclusions. In 2017, Align Technology introduced the Invisalign with Mandibular Advancement Feature (IMAF) which replicates the action of functional appliances. As this device is new to clinical practice, there is limited literature on its clinical efficiency. This case report describes the orthodontic management of a 12-year-old male patient having skeletal Class II malocclusion due to mandibular retrognathia. As the patient was experiencing active growth, the IMAF appliance was chosen for his treatment. The IMAF appliance appears to be successful in the treatment of Class II malocclusion with mandibular retrognathism in a growing patient. As with all functional appliances, the correction of the malocclusion is a result of both skeletal and dental effects and the IMAF presents the advantage of producing less proclination of the lower incisors compared to other functional appliances.

Effect of prior knowledge about treatment on cephalometric measurements

OBJECTIVE

We hypothesised that prior knowledge of details for a growth modification treatment influences cephalometric measurements and results in a detectable bias.

DESIGN

Observational study.

SETTING

University teaching facility.

METHODS

Six orthodontic residents assessed 48 lateral cephalograms taken before and after functional appliance treatment from 24 patients. The residents assessed six cephalometric measurements, (Cd-Pog, Cd-Me, Ar-Pog, Ar-Me, Go-Me, SNB) over three separate sessions, in either a random concealed order or as matched pairs with information about treatment and time disclosed.

RESULTS

When information was disclosed, five out of the six cephalometric measurements were significantly higher that the corresponding cephalometric measurements taken randomly with undisclosed information. The bias was in the range of 1.6-3.2 mm for linear measurements and was 1.1° for SNB.

CONCLUSION

Disclosing treatment information does introduce systematic errors in cephalometric measurements. Cephalometric analysis in orthodontic clinical research should be carried out by assessors who are blinded to treatment details, to minimise risk of bias.

Soft tissue profile changes during treatment of patients with Class II malocclusion

Introduction/Objective. The class II malocclusion results in disbalanced facial harmony, primarily noticeable in the profile and the lower facial third. Aside from skeletal evaluation, orthodontic diagnosis and treatment planning should include facial soft tissue analysis. The aim of the study was to identify the soft tissue profile outcomes of orthodontic treatment of Class II, division 1 malocclusion patients and to determine if these changes are related with the different treatment protocol. Methods. The first group was the non-extraction group (25 patients) treated first with the Herbst appliance, and the second group was four premolars extraction group (25 patients) treated with a multibracket appliance. The patients? cephalograms and pre- and post-treatment profile photographs were used. Results. The improvement in the non-extraction group was evident in the decrease of the nasomental angle, the angle representing the projection of the upper lip to the chin, as well as the upper lip angle. In the extraction group, the nasolabial angle showed a significant increase. Soft tissue variables showed significant differences between the groups: the total facial angle or facial convexity including the nose and the angle presenting the projection of the upper lip to chin. Conclusion. The patients treated without extractions showed a significant improvement of the convex profile and favorable soft tissue changes in the lower third of the face.

Effect of fixed functional appliances on pharyngeal airway dimensions in Skeletal Class II individuals - A scoping review

BACKGROUND

Skeletal Class II malocclusion due to a retrognathic mandible produces a backwardly positioned tongue and soft palate, emanating compromised upper airway dimensions and breathing difficulties.

AIMS

The present review aims to explore and concise the findings of the existing studies assessing the effects of fixed functional appliances on pharyngeal airway dimensions by advancing the mandible.

DESIGN

A literature search was carried out on MEDLINE/PubMed, Cochrane Library, Science direct, Semantic Scholar and Google Scholar databases for studies up to December 2020, resulting in 1037 studies. Specified inclusion/exclusion criteria guided the selection of 18 relevant articles. The sample size, type of the appliance, method of assessment and outcomes of these articles were assessed in detail and tabulated.

RESULTS

Out of 18 studies included, 12 were retrospective longitudinal and the remaining were clinical trials. Majority of the studies (72%) reported a positive influence of the fixed functional appliances on the dimensions of the oropharyngeal and hypopharyngeal airways with minimal effects on nasopharyngeal airway.

CONCLUSION

Thus, it can be concluded that fixed functional appliances have a beneficial effect on the middle and lower pharyngeal airway dimensions by advancing the mandible.

ADDING TEMPORARY ANCHORAGE DEVICES (TADs) TO THE FORSUS™ CLASS II CORRECTION SYSTEM MAY NOT ENHANCE THE SAGITTAL SKELETAL EFFECTS BUT MAY CONTROL THE INCLINATION OF THE MANDIBULAR INCISORS

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

A comparison of the effects of Forsus appliances with and without temporary anchorage devices for skeletal Class II malocclusion. Liu L, Zhan Q, Zhou J, Kuang Q, Yan X, Zhang X, Shan Y, Lai W, Long H. Angle Orthod. 2020 Dec 30. doi:10.2319/051120-421.1. Epub ahead of print. PMID: 33378419.

SOURCE OF FUNDING

National Natural Science Foundation of China (No. 82,071,147, 81,571,004, and 81,500,884).

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

Effects of Sabbagh Universal Spring 2 appliance on cephalometric indices in patients with Class II division 1 versus division 2 malocclusions: A preliminary before-after clinical trial

BACKGROUND

Since there is no comparison between the effects of Sabbagh Universal Spring 2 (SUS2) appliance on Class II division 1 (div 1) versus Class II division 2 (div 2) patients, this preliminary study was conducted to comparatively assess, for the first time, the effects of SUS2 on 34 cephalometric indices in Class II/1 versus Class II/2 patients.

MATERIALS AND METHODS

This before-after clinical trial was conducted on 75 observations of 25 patients with Class II malocclusion, of whom 12 (9 females and 3 males) had Class II div 1 and 13 (11 females and 2 males) had Class II div 2 malocclusion diagnosed by clinical examination and cephalometric assessment. The growth level of all patients had to be CS3 according to the cervical vertebral maturation index. Lateral cephalographs were obtained before treatment (T0) and the patients underwent fixed orthodontic treatment. Lateral cephalographs were taken again (T1) and the patients received SUS2 functional appliance for 6 months. A final lateral cephalograph (T2) was then obtained. Thirty-four dentoskeletal indices were measured on lateral cephalographs, and changes in indices over time were determined and compared using repeated-measures analysis of variance, post hoc test, and t-test (α =0.05).

RESULTS

Within-group comparisons showed significant changes over time in SNB, sella nasion (SN)/occlusal plane, ANB, articular (Ar)-pogonion (Pog), L1-NB, condylion (Co)-gnathion, S-Ar/Ar-G, B-RL1, L1/nasion-point B (NB), U6-RL2, incisor mandibular plane angle, overjet, overbite, U1-RL1, and L1-RL2 (P < 0.05). The two groups were significantly different in terms of changes occurred to overjet, interincisal angle, U1/RL1, L1-NB, U1-NA, U1/NA, the Jarabak ratio, A-RL1, U1/SN, Pog-NB, and Co-A (P < 0.05).

CONCLUSION

The SUS2 showed therapeutic efficacy for both Class II div 1 and 2 patients although it more commonly caused dentoalveolar rather than skeletal changes. Our study showed no considerable difference between the two groups after using this appliance, and the difference in the Jarabak ratio indicated better long-term growth pattern of div 2 patients and its conformity with camouflage treatments (mild or moderate Class II).

Characteristics of craniofacial morphology and factors affecting them in patients with isolated cleft palate

Background

Myriad maxillo-mandibular occlusal relationships are observed in patients with isolated cleft palate (ICP), unlike in patients with other cleft types, such as cleft lip and palate.

Objectives

This study aimed to categorise the characteristics of craniofacial morphology in patients with ICP, and investigate the clinical factors affecting these categorised morphological characteristics.

Methods

Thirty-six girls with ICP (age (mean ± SD): 5.36 ± 0.36 years) underwent cephalometric measurement. Their craniofacial morphology was categorised using cluster analysis. Profilograms were created and superimposed onto the standard Japanese profilograms to visualise the morphological characteristics of each group (cluster). The mean values and variations in the linear and angular measurements of each group were compared with the Japanese standards and statistically analysed using Dunnett’s test after the analysis of variance. Fisher’s exact test was used to analyse the differences between the cleft types (cleft in the hard and/or soft palate) and skills of the operating surgeons in the groups.

Results

Cluster analysis of craniofacial morphologies in patients with ICP resulted in the formation of three categories: the first cluster exhibited a relatively harmonious anteroposterior relationship between the maxilla and the mandible (22.2%); the second cluster exhibited crossbite owing to a significantly smaller maxilla (33.3%); and the third cluster exhibited a smaller mandible with posterior rotation showing skeletal class II malocclusion (44.4%). Differences in cleft types and surgeons were not associated with the distribution of patients in each cluster.

Conclusions

Patients with ICP exhibited characteristic morphological patterns, such as bimaxillary retrusion or severe mandibular retrusion, besides the anterior crossbite frequently found in patients with cleft lip and palate . Understanding the typical morphological characteristics could enable better diagnostic categorisation of patients with ICP, which may eventually improve orthodontic treatment planning.

Soft tissue evaluation of functional therapy in growing patients with Class II malocclusion: a long-term study

OBJECTIVE

The objective of this study was to analyse the soft tissue changes produced by the functional treatment of mandibular advancement in growing Class II patients.

MATERIALS

The treated group consisted of 25 Caucasian patients (12 females and 13 males) with dento-skeletal Class II malocclusion treated with functional therapy (Activator). All patients were evaluated before treatment (T1; mean age, 9.9 years), at the end of functional treatment phase (T2; mean age, 11.9 years), and at a post-pubertal follow-up observation (T3; mean age, 18.5 years). The treated group was compared with a matched control group of 25 untreated subjects (13 females, 12 males) with untreated Class II division 1 malocclusion. Statistical comparisons between the two groups were performed with independent samples t-tests (P < 0.05).

RESULTS

Significant improvements were found during the long-term interval for mandibular sulcus (9.9°) and the profile facial angle (9.8°) in the treated group. No significant effects were found in terms of lower face percentage between the two groups.

CONCLUSION

Removable functional appliances induced positive effects on the soft tissue profile in Class II growing subjects with good stability in the long-term.

Maxillary dento-skeletal outcomes after orthopedic forward (class III) and backward (class II) traction in growing subjects

BACKGROUND

This retrospective study investigated the treatment effects produced by two orthopedic appliances, an extraoral orthopedic traction on Stephenson plate (SP) in skeletal Class II malocclusion and Delaire Facial Mask (FM) in skeletal Class III malocclusion.

METHODS

FM Group comprised 25 patients (13 males; 12 females, mean age 9.3 years, CS 1-2) undergoing Delaire Facial Mask therapy (mean treatment duration 1.5 years ± 1.2, 700-800 gr per side). SP Group comprised 24 patients (9 males; 15 females, mean age 10.5 years ± 1.9, CS 1-3) treated with extraoral orthopedic traction on Stephenson plate (mean treatment duration 1.6 years ± 0.8, 700-900 gr per side). For all subjects lateral cephalograms before (T0) and after (T1) therapy were obtained and traced. Descriptive statistics, t-test and Shapiro-Wilks test were calculated for each variable.

RESULTS

A mesial movement of the maxillary bone of 2.4 mm in the FM group and a distal movement in the PS group (0.4 mm) was found. SNA° was reduced 1.4° after SP and increased 0.7° after FM. The overjet decreased by 4 mm after SP, while it grew after FM by 2.4 mm, as well as molars relationships (4.5 vs. 0.8 mm).

CONCLUSIONS

Facemask induced greater skeletal movements than extraoral traction on Stephenson plate. PS produced a limited downward movement of the whole maxilla together with notable incisors and molars back corrections. Based on our results, it could be speculated that orthopedic mesial traction of maxillary bone may result easier than the distal movement.

Proposal of Dental Hygiene Diagnosis for Cancer Patients Based on Dental Hygiene Process of Care in Acute Care Hospitals: A Narrative Review

A narrative review was conducted to propose dental hygiene diagnoses for cancer patients based on dental hygiene process of care in acute care hospitals. Six researchers, including three dental hygienists, all with expertise in oral healthcare for patients with cancer, decided the review outline. All researchers reviewed the literature and developed terminology for dental hygiene diagnoses. The team then modified the terminology and discussed its clarity and acceptability to develop an initial list of dental hygiene diagnosis names according to the dental hygiene human needs conceptual model subscales. In wholesome facial image, one new diagnosis was developed. In protection from health risks, 15 new diagnoses were developed. In biologically sound and functional dentition, 10 new diagnoses were developed. In skin and mucous membrane integrity of the head and neck, 10 new diagnoses were developed. In freedom from head and neck pain, two new diagnoses were developed. In freedom from anxiety and stress, eight new diagnoses were developed. In responsibility for oral health, five new diagnoses were developed. In conceptualization and understanding, three new diagnoses were developed. Based on this study, it is necessary for the academic community to develop a better taxonomy of dental hygiene diagnoses pertaining to dental hygienist clinical practice.

Stability of Class II corrections with removable and fixed functional appliances: A literature review

BACKGROUND

Class II functional appliances have been used in orthodontics for over 100 years. Although the stability of corrections is one of the main goals of orthodontic treatment, there is a paucity of longitudinal studies on the long-term stability of treatment of Class II malocclusion based on functional appliances.

METHODS

This narrative review attempts to summarize the limited related evidence available and discusses the clinical implications of important aspects related to occlusal and skeletal changes that arise after Class II malocclusion treatment with functional appliances.

RESULTS

The occlusal changes obtained through Class II functional treatment do mostly exhibit long-term stability. While mild posttreatment changes occurred, they were most likely due to physiologic aging processes and not likely associated with actual treatment relapse. Long-term retention in the lower jaw would be particularly beneficial. A stable occlusion with good intercuspation in the posterior arches seems more likely to preserve a Class I occlusion after treatment through dentoalveolar compensatory mechanisms. After treatment, the maxilla and the mandible do grow anteriorly, with the mandible growing more than the maxilla. Patients treated with functional appliances are not likely to develop TMJ disorders over the long term.

CONCLUSIONS

Long term skeletal corrections achieved with functional appliances seem to be overall stable. Class II molar and overjet relapses can be likely explained by a combination of tooth movement and an unfavorable posttreatment maxillomandibular growth pattern, especially when combined with unstable interdigitation of the posterior teeth. No specific intermaxillary retention approach has been assessed yet.

Dentoskeletal and soft-tissue changes comparison between the Jasper Jumper and Twin Force Bite Corrector in Class II malocclusion patients: A retrospective study

OBJECTIVE

This retrospective study aimed to compare the dentoskeletal and soft-tissue changes in Class II malocclusion patients treated with Jasper Jumper and Twin Force Bite Corrector associated with fixed orthodontic appliances.

MATERIAL AND METHODS

The sample comprised 60 subjects divided into 3 groups. Patients with Class II malocclusion, mandibular retrusion, slight or no crowding and with no previous orthodontic treatment were eligible. Group 1 comprised 20 patients treated with the Jasper Jumper (JJ), with an initial age of 12.39 years. Group 2 comprised 20 patients treated with the Twin Force (TF), with an initial age of 11.83 years. The control group consisted of 20 untreated Class II subjects with an initial age of 12.13 years. Intergroup pretreatment comparisons were performed with One-way analysis of variance and intergroup treatment changes were compared with the Analysis of Covariance, both followed by Tukey test.

RESULTS

The TF group showed greater increase in mandibular length (6.23mm±4.64, P=0.004) than the control group (2.94mm±1.75). The mandibular incisors in the experimental groups presented significantly greater labial inclination and protrusion than the control (Md1.NB; JJ: 4.19°±2.09; TF: 4.46°±6.83; control: 1.13°±2.08, P=0.000/Md1-NB; JJ: 1.95mm±1.45; TF: 1.74mm±1.79; control: 0.31mm±0.81, P=0.000). In addition, the treated groups also showed significantly improvement of the dental relationships (Overjet; JJ: -4.05mm±4.64; TF: -3.80mm±2.12; control: 0.05mm±1.12, P=0.000/Overbite; JJ: -2.52mm±1.46; TF: -2.93mm±2.13; control: -0.63mm±1.35, P=0.000).

CONCLUSION

The Jasper Jumper and Twin Force associated to fixed appliances were effective in correcting Class II malocclusion with a combination of skeletal and dentoalveolar changes. However, the TF seems to provide more skeletal effects with greater maxillary growth restriction and mandibular length increase when compared to the JJ.