The Impact of Orthodontic Treatment on Masticatory Performance: A Literature Review

The aim of this narrative review was to evaluate the possible association between orthodontic therapy and improved masticatory function. A search strategy was conducted using the PubMed database for up to January 2020 using the keywords "mastication" and "orthodontics". Only human studies investigating mastication in orthodontics settings were selected. The search strategy resulted in 1,011 articles, out of which 57 were included in the final analysis. Investigations have generally agreed that masticatory and chewing functions improved post-orthodontic and orthognathic treatments. Studies also showed improvement in the quality of life of patients' post-orthodontic treatment. The articles examined reinforced that besides esthetic reasons, orthodontic therapy does improve the masticatory and chewing functions of individuals, ultimately enhancing their health-related quality of life

Does asymmetry in the stomatognathic system correlate with body posture impairments?: A systematic review

Objectives: To assess the potential correlations between anatomical and functional asymmetry in the stomatognathic system and body posture impairments. Methods: Literature search using the Medline, SCOPUS, LILACS and SciELO databases, the Cochrane Library and a manual search. Experimental and observational studies were included with no restrictions as to the type of asymmetry. Type of asymmetry, treatment and/ or recording conditions, follow-up, postural examinations, main results and clinical implication were extracted, and risk of bias was assessed. Results: Eleven articles (including one randomized clinical trial) were retrieved. The risk of bias was medium in 6 studies and high in the remaining investigations. Only three studies, all with a high risk of bias and without follow-up, reported significant correlations between the asymmetry in the stomatognathic system and body posture impairments. Discussion: According to the limited present evidence, asymmetry in the stomatognathic system does not appear to correlate with body posture impairments at a clinically relevant level

Herbst appliance palatally anchored in the treatment of dental Class II malocclusion: a case report

Introduction: In this case report, we present a Class II malocclusion correction using only an Herbst appliance palatally anchored with miniscrews. Case presentation: 11.9-year-old female presented with the chief complaints of increased anterior upper teeth proclination; permanent dentition with a Class II division I malocclusion; before sagittal correction with Herbst appliance, we applied a palatal screw to obtain maxillary expansion. The device was removed after 12 months of treatment. Conclusion: This clinical case showed a simple orthopedic and dentoalveolar approach using skeletal anchorage, which can effectively correct a dental Class II malocclusion and frontal proclination of the upper incisors

Facial soft tissue changes during the pre-pubertal and pubertal growth phase: a mixed longitudinal laser-scanning study

BACKGROUND/OBJECTIVES: Facial soft tissues changes during growth roughly tend to mimic the underlying hard tissues, but not completely. The aim of this mixed longitudinal study was to assess facial growth among pre-pubertal and pubertal subjects without malocclusion using a non-invasive three-dimensional laser scanning system. SUBJECTS/METHODS: Fifty-nine subjects (30 females and 29 males) aged at baseline 5.4-8.9 years with normal occlusion were clustered into the younger, older pre-pubertal, and pubertal groups according to age and the absence/presence of a standing height growth spurt. Three-dimensional facial images were obtained using laser scanners for five consecutive years. Several transversal, sagittal, and vertical parameters were assessed for between and within group comparisons. RESULTS: Significant overall changes of almost all parameters were seen within each group (P 0.05). The younger pre-pubertal group showed greater annual growth rates of lip prominence; both pre-pubertal groups showed greater rates in facial middle third height. The pubertal group showed greater annual rates in facial profile angle changes during the growth peak. LIMITATIONS: A high standing height increment (7cm) was used as the threshold for subject allocation in the pubertal group. CONCLUSIONS: Soft tissue facial growth has generally similar amounts and rates irrespective of the pubertal growth spurt. Pre-pubertal subjects show greater annual rates of facial middle third height changes while pubertal subjects show greater annual rates of chin protrusion

Sagittal and vertical craniofacial growth and attainment of circumpubertal middle phalanx maturation (MPM) stages: A multiple regression study

Introduction: Orthodontic treatment for most of the skeletal malocclusions have specific optimal timing according to the skeletal maturation phases. The knowledge of whether attainment of a specific maturation phase is associated with the different sagittal and vertical craniofacial growth pattern then becomes of clinical relevance. Aim: This cross-sectional study evaluated whether sagittal and vertical craniofacial growth pattern, has an association with the age of attainment of the circumpubertal skeletal maturation phases. Materials and methods: A total of 300 subjects (170 females and 130 males) were included in the study (mean age, 12.0 ±1.5 years; range, 8.3-15.6 years). These subjects were equally distributed in the circumpubertal middle phalanx maturation (MPM) stages 2, 3 and 4. Subsequently,multiple regression models were run for each MPM stage group to assess the significance of the association of cephalometric parameters(SNA, SNB, ANB, PP/MP, CoGoMe, SN/MP and NSBa angles) with age of attainment of the corresponding MPM stage (in months). Results: Only sex yielded significant associations, with females having anticipated attainment of each of the circumpubertal MPM stage. Conclusion: These results show no significant correlations of the different sagittal and vertical cephalometric parameters with the age of attainment of the circumpubertal skeletal maturation phases

Cervical vertebral maturation method and mandibular growth peak: A longitudinal study of diagnostic reliability

Background/objectives: The capability of the cervical vertebral maturation (CVM) method in the identification of the mandibular growth peak on an individual basis remains undetermined. The diagnostic reliability of the six-stage CVM method in the identification of the mandibular growth peak was thus investigated. Subjects/Methods: From the files of the Oregon and Burlington Growth Studies (data obtained between early 1950s and middle 1970s), 50 subjects (26 females, 24 males) with at least seven annual lateral cephalograms taken from 9 to 16 years were identified. Cervical vertebral maturation was assessed according to the CVM code staging system, and mandibular growth was defined as annual increments in Co\u2013Gn distance. A diagnostic reliability analysis was carried out to establish the capability of the circumpubertal CVM stages 2, 3, and 4 in the identification of the imminent mandibular growth peak. Results: Variable durations of each of the CVM stages 2, 3, and 4 were seen.The overall diagnostic accuracy values for the CVM stages 2, 3, and 4 were 0.70, 0.76, and 0.77, respectively. These low values appeared to be due to false positive cases. Limitations: Secular trends in conjunction with the use of a discrete staging system. In most of the Burlington Growth Study sample, the lateral head film at age 15 was missing. Conclusions/Implications: None of the CVM stages 2, 3, and 4 reached a satisfactorily diagnostic reliability in the identification of imminent mandibular growth pea

Treatment effects of removable functional appliances in pre-pubertal and pubertal Class II patients: A systematic review and meta-analysis of controlled studies

BACKGROUND: Treatment effects of removable functional appliances in Class II malocclusion patients according to the pre-pubertal or pubertal growth phase has yet to be clarified. OBJECTIVES: To assess and compare skeletal and dentoalveolar effects of removable functional appliances in Class II malocclusion treatment between pre-pubertal and pubertal patients. SEARCH METHODS: Literature survey using the Medline, SCOPUS, LILACS and SciELO databases, the Cochrane Library from inception to May 31, 2015. A manual search was also performed. SELECTION CRITERIA: Randomised (RCTs) or controlled clinical trials with a matched untreated control group. No restrictions were set regarding the type of removable appliance whenever used alone. DATA COLLECTION AND ANALYSIS: For the meta-analysis, cephalometric parameters on the supplementary mandibular growth were the main outcomes, with other cephalometric parameters considered as secondary outcomes. Risk of bias in individual and across studies were evaluated along with sensitivity analysis for low quality studies. Mean differences and 95% confidence intervals for annualised changes were computed according to a random model. Differences between pre-pubertal and pubertal patients were assessed by subgroup analyses. GRADE assessment was performed for the main outcomes. RESULTS: Twelve articles (but only 3 RCTs) were included accounting for 8 pre-pubertal and 7 pubertal groups. Overall supplementary total mandibular length and mandibular ramus height were 0.95 mm (0.38, 1.51) and 0.00 mm (-0.52, 0.53) for pre-pubertal patients and 2.91 mm (2.04, 3.79) and 2.18 mm (1.51, 2.86) for pubertal patients, respectively. The subgroup difference was significant for both parameters (p<0.001). No maxillary growth restrain or increase in facial divergence was seen in either subgroup. The GRADE assessment was low for the pre-pubertal patients, and generally moderate for the pubertal patients. CONCLUSIONS: Taking into account the limited quality and heterogeneity of the included studies, functional treatment by removable appliances may be effective in treating Class II malocclusion with clinically relevant skeletal effects ifperformed during the pubertal growth phase

Accuracy of the digital workflow for guided insertion of orthodontic palatal TADs: a step-by-step 3D analysis

BACKGROUND: The introduction in the orthodontic field of the digital workflow for guided insertion of palatal TADs and the development of the 1-visit protocol led to the reduction of chair time and the possibility of complete customization of designs and materials. Conversely, the reduction of operative steps implicates a lower tolerance of deviations between the planned and the actual position of the miniscrews, particularly when the orthodontic device is fixed on 4 palatal TADs or has a rigid structure. This study aims to analyze the influence of each step of the digital workflow on the deviation of the miniscrews' axis of insertion in a bicortical sample. The null hypothesis is that there are no significant differences in the deviations among the operative steps. METHODS: 33 subjects were selected for insertion of bicortical palatal miniscrews with a 1-visit protocol. Digital files were collected at the three stages of the workflow (i.e., digital planning, laboratory prototype, post-insertion impression). A 3D software analysis was performed on a total of 64 miniscrews. After automatic shape recognition of the guiding holes of the digital plan and the scanbodies of the laboratory prototype and post-insertion impression as geometric cylinders, their three-dimensional longitudinal axis was traced and the deviation among them was calculated. Friedman test with Bonferroni correction was performed to assess the significance of the deviations among the three steps, with significance set at p < 0.05. RESULTS: The laboratory step has a significantly lower degree of deviations (2.12° ± 1.62) than both the clinical step (6.23° ± 3.75) and the total deviations (5.70° ± 3.42). No significant differences were found between miniscrews inserted on the left or the right side. CONCLUSIONS: This study suggests that laboratory procedures such as surgical guide production or rapid prototyping don't play a significant role in the degree of deviations between the planned and the positioned palatal TADs. Conversely, the clinical steps have a bigger influence and need to be carefully evaluated. Despite this difference, there is a cumulative effect of deviations that can lead to the failure of the 1-visit protocol

Reliability of a Novel CBCT-Based 3D Classification System for Maxillary Canine Impactions in Orthodontics: The KPG Index

The aim of this study was to evaluate both intra- and interoperator reliability of a radiological three-dimensional classification system (KPG index) for the assessment of degree of difficulty for orthodontic treatment of maxillary canine impactions. Cone beam computed tomography (CBCT) scans of fifty impacted canines, obtained using three different scanners (NewTom, Kodak, and Planmeca), were classified using the KPG index by three independent orthodontists. Measurements were repeated one month later. Based on these two sessions, several recommendations on KPG Index scoring were elaborated. After a joint calibration session, these recommendations were explained to nine orthodontists and the two measurement sessions were repeated. There was a moderate intrarater agreement in the precalibration measurement sessions. After the calibration session, both intra- and interrater agreement were almost perfect. Indexes assessed with Kodak Dental Imaging 3D module software showed a better reliability in z-axis values, whereas indexes assessed with Planmeca Romexis software showed a better reliability in x- and y-axis values. No differences were found between the CBCT scanners used. Taken together, these findings indicate that the application of the instructions elaborated during this study improved KPG index reliability, which was nevertheless variously influenced by the use of different software for images evaluation