Herbst appliance anchored to miniscrews in the upper and lower arches vs standard Herbst: A pilot study.

INTRODUCTION: The aim of this pilot study was to present the preliminary results of Class II malocclusion treatment using a skeletally anchored Herbst appliance with miniscrews inserted in the maxillary and mandibular arches to improve anchorage control and skeletal effects. METHODS: The treatment group (TG) consisted of 13 patients (10 males [M], 3 females [F]; mean age of 12.8 years) with Class II Division 1 malocclusion who were treated with the Herbst appliance and miniscrews inserted in the maxillary and mandibular arches. They were compared with a control group (CG) of 13 patients (10 F, 3 M, mean age of 12.2 years) with Class II Division 1 malocclusion treated with the standard Herbst appliance without miniscrews. Lateral cephalograms were taken before and after Herbst treatment, and cephalometric analysis was performed. RESULTS: In the TG group SNB (°) increased by 2.9°, whereas in CG group SNB (°) increased by 1.1° (P = 0.017). ANB (°) decreased in both groups: -3.3° in the TG group vs -1.3° in the CG group (P = 0.014). Pg-OLp distance increased in both groups: 5.70 mm in the TG group and 0.8 mm in the CG group (P = 0.022). Mandibular incisors proclined 1.6° in the TG group and 3.7° in the CG group. CONCLUSIONS: Herbst treatment reinforced with 4 miniscrews (2 in each arch) increased the orthopedic effect of treatment in growing patients with Class II malocclusion.

Immediate versus delayed loading: comparison of primary stability loss after miniscrew placement in orthodontic patients-a single-centre blinded randomized clinical trial.

INTRODUCTION: The aim of this randomized clinical trial was to compare torque recordings at insertion time and 1 week post-placement between immediately loaded orthodontic miniscrews and an unloaded control group. TRIAL DESIGN: This RCT was designed as parallel with an allocation ratio of 1:1. METHODS: Eligibility criteria to enroll patients were: needs of fixed orthodontic treatment, no systemic disease, absence of using drugs altering bone metabolism. All patients were consecutively treated in a private practice and the miniscrews were placed by the same author. Patients received ORTHOImplant (3M Unitek) miniscrews and they were blindly divided in two groups: group 1 screws were unloaded between T0 and T1, group 2 received immediately loaded screws with NiTi coil. For each patient, maximum insertion torque (MIT) was evaluated at T0. After 1 week, without loading, the screw torque was measured again (T1) and at the end of the treatment maximal removal torque was evaluated (T2). Torque variation in the first week was considered as the primary outcome. RANDOMIZATION: A randomization list was created for the group assignment, with an allocation ratio of 1:1. BLINDING: The study was single blinded in regard of the statistical analysis. RESULTS: Patients enrolled in the clinical trial were 51 for a total of 81 miniscrews. The recruitment started in November 2012 and the observation period ended in August 2014. Twenty-six and twenty-five patients were analysed in group 1 and 2, respectively. The MIT mean in each placement time was 18.25 Ncm (SD = 3.00), 11.41 Ncm (SD = 3.51) and 10.52 Ncm (SD = 5.14) at T0, T1, and T2 time, respectively. In group 1, the torque decrease between T1 and T0 was statistically higher compared to group 2 (P value = 0.003). Statistically significant effects of the placement times on MIT were found (P value <0.0001). No serious harm was observed. LIMITATIONS: This study was performed using only direct force on the miniscrew and not using the miniscrew as an indirect anchorage. It was not possible to obtain quantitative data on bone quality or root proximity to miniscrews. CONCLUSIONS: A significant stability loss was observed in the first week in both groups; Group 1 showed a statistically higher torque loss in the first week when compared to the immediately loaded group. There were statistically significant effects of the measurement times on MIT and of the miniscrew location on MIT. The overall failure rate was 7.4%. TRIAL REGISTRATION: This trial was not registered. PROTOCOL: The protocol was not published before trial commencement.

Evaluation of the Co-Go-Me angle as a predictor in Class II patients treated with Herbst appliance and skeletal anchorage: a retrospective cohort study.

Introduction: A condylion-gonion-menton (Co-Go-Me) angle threshold of 125.5° has been introduced as a predictive parameter of cephalometric mandibular response in the orthopedic treatment of growing Class II patients with functional appliances, despite some contradictions in the literature. Considering the lack of studies evaluating the role of skeletal anchorage, this study aims to reassess the threshold of 125.5° in the Co-Go-Me angle as a useful predictor in growing skeletal Class II patients treated with acrylic splint Herbst appliance and two mini-screws in the lower arch (STM2). Methods: Thirty-five consecutively treated patients (20 males, 15 females; mean age, 11.37 years) with mandibular retrusion were classified into two groups according to their Co-Go-Me baseline values (Group 1, <125.5°; Group 2, >125.5°). The STM2 protocol involved the use of the MTH Herbst appliance with an acrylic splint in the lower arch and two interradicular mini-screws as anchorage reinforcement. Cephalometric analysis was performed by the same operator for each patient at baseline (T0) and at the end of the Herbst phase (T1). The effects of time and group on the variables were assessed by a repeated-measures analysis of variance. The primary research outcome was the difference between the groups in terms of mandibular responsiveness to treatment referred to as the relative difference (T1-T0) in Co_Gn. Results: The mean duration of the treatment was 9.5 months. No statistically significant differences between groups were detected at baseline, except from the expected SN/GoMe° (p < 0.001) and Co-Go mm (p = 0.028). No statistically significant changes between groups, which were caused by the treatment, were found considering the mandibular sagittal and vertical skeletal parameters. Similarly, no statistically significant differences were found in the dental changes between the high-angle and low-angle patients, apart from the upper molar sagittal position (p = 0.013). Discussion and conclusions: The 125.5° threshold in the Co-Go-Me value was not a reliable predictive parameter for the mandibular response in growing patients treated with the MTH Herbst appliance and lower skeletal anchorage. Due to its effective control in the sagittal and vertical planes, the STM2 technique might be an appropriate protocol to use in treating skeletal Class II patients, regardless of the growth pattern.

Pulp chamber temperature changes and enamel surface analysis during orthodontic composite removal using 3 different burs in a repeatable approach: an experimental study.

BACKGROUND: During the debonding phase every clinician has to take care of preserving the enamel structure and tooth temperature. The objective of this study is to analyze in vitro the increase of the pulp chamber temperature and the wearing of enamel surface, during adhesive removal after debonding. METHODS: 60 extracted human teeth were selected. An orthodontic bracket was bonded on each tooth and after bracket removal, intraoral scanner pictures were used to evaluate ARI for each tooth. 3 different burs were tested: Tungsten-carbide multiple blade, Arkansas stone and Ceramic bur. A mechanical arm controlled by a dedicated software was used to reproduce a repeatable act of composite removal. To analyze in vitro the pulp chamber temperature during the composite removal procedure, teeth were treated endodontically placing a thermocouple through the root canal from the apex. A software registered temperature changes in a continuous manner. The enamel surface of every tooth was tested after the removal of composite with an optical stereoscopic microscope. RESULTS: An association existed between maximum internal pulp chamber temperature variation and irrigation (P-value < 0.0001) and between maximum internal pulp chamber temperature variation and bur type (P-value = 0.0133), with a significantly lower temperature increase produced by the Arkansas bur. A significant difference among groups was detected for ESI and EDI assessment (P-value = 0.002, P-value = 0.010). CONCLUSIONS: Considering the initial setup, temperature variation analysis showed more conservative results using the Arkansas burs with irrigation. ESI and EDI indexes showed significant enamel surface damage using Tungsten-carbide burs.

Long-term dentoskeletal changes of class II growing patients' treatment with the propulseur universal light appliance. A prospective controlled study.

BACKGROUND: Class II is one of the most common malocclusions. The prevailing aspect in Class II patients is a mandibular deficiency. Various removable and fixed functional therapies are used in order to enhance the mandibular growth or position. The aim of this prospectively controlled study was to evaluate long-term dentoskeletal changes obtained by a functional appliance for Class II. METHODS: Prospective controlled study, based on a sample size calculation. 26 Class II Division 1 patients (11.8±1.5 years) were consecutively treated with the propulseur universal light (PUL) appliance and a multi bracket appliance (PG), they were compared to a sample of 26 Class II untreated patients (11.5±0.8 years) (CG). Lateral cephalograms were taken before and after the PUL therapy, and after multibracket treatment. Interaction analysis was carried out to test whether the PUL parameters in treatment groups were different according to the acquisition times, using the Linear Mixed-Effects Model. RESULTS: Significant ANB, Overjet and WITS differences existed in treatment groups according to the time. In particular, comparing to T1 vs. T0, the relative difference (RD) means in the control group were -0.34, -0.31 and 0.17 for ANB, Overjet and WITS, respectively. The corresponding RD means in the treated group PG were -1.58, -4.27 and -2.38. Comparing to T2 vs. T0, the RD means in the control group were -0.36, -0.51 and 0.63 for ANB, Overjet and WITS, respectively. While the corresponding RD means in the treated group were -2.08, -5.12 and -2.50. CONCLUSIONS: The PUL appliance successfully corrected class II malocclusion. The long term correction was mainly due to dentoalveolar effects: therapy success was 91% for overjet correction and 76% for ANB correction. During the post functional appliance period, overjet was stable in 77% of the treated subjects, and ANB in 74% of the treated subjects.

Patients' expectations assessment in orthodontic treatment: findings from a questionnaire survey.

BACKGROUND: The aim of this study was to analyze the psychological aspects of patients during their orthodontic treatment, evaluating their expectations during treatment comparing Greek patients to Italian patients. METHODS: This cross sectional descriptive study involved a sample of 228 patients (113 Italians -115 Greeks) undergoing fixed or removable orthodontic treatment. A questionnaire comprising of six questions was used and patients scored each question on a 0-10 Scale. Participants completed a validated questionnaire measure of orthodontic expectations that was tested for reliability. Descriptive analysis of the responses was undertaken, and comparisons between boys and girls, as well as between Greek and Italian patients, was made. The expectation score was calculated by summarizing the 6 items (A1 to A6). Reliability Analysis was performed using the Item-test, Item-rest correlation and the Cronbach's α. Items with a Cronbach's α coefficients greater than 0.7 are considered acceptable. To investigate the effect of the City and Gender on the expectation score, an univariate analysis was carried out by the Wilcoxon Rank Sum Test. Differences, with a P value less than 0.05, were selected as significant. RESULTS: Overall expectation Cronbach's α coefficient (internal consistency) was 0.73 (95% CI: 0.64-0.81). The mean of expectation items was 7.8 (SD=1.8). A significant slight correlation was found between motivation (item A1) and main reason of treatment (item A3) (r=0.17; P=0.0122). Moreover, there was a significant moderate correlation between compliance (item A4) and expectation (item A6) (r=0. 58; P<0.0001). CONCLUSIONS: Male showed a significant higher overall score compared to female sample, as well as Greek patients compared to Italians.

Tooth loss caused by displaced elastic during simple preprosthetic orthodontic treatment.

The use of elastics to close a diastema or correct tooth malpositions can create unintended consequences if not properly controlled. The American Association of Orthodontists recently issued a consumer alert, warning of "a substantial risk for irreparable damage" from a new trend called "do-it-yourself" orthodontics, consisting of patients autonomously using elastics to correct tooth position. The elastics can work their way below the gums and around the roots of the teeth, causing damage to the periodontium and even resulting in tooth loss. The cost of implants to replace these teeth would well exceed the cost of proper orthodontic care. This damage could also occur in a dental office, when a general dentist tries to perform a simplified orthodontic correction of a minor tooth malposition. The present case report describes a case of tooth loss caused by a displaced intraoral elastic, which occurred during a simple preprosthetic orthodontic treatment.