Upper Midline Correction Using the Mesial-Distalslider.

AIM: The purpose of the present study is the three-dimensional (3D) analysis of molar and incisor movements that occur during the correction of the upper midline deviation by using the Mesial-Distalslider appliance. MATERIALS AND METHODS: A total of 20 consecutive patients (12 women and 8 men; mean age 19.6 ± 11.1 years) were selected from the Orthodontic Department of Heinrich-Heine University of Düsseldorf. To correct the upper midline deviation (>2 mm), the patients were treated with asymmetric mechanics (mesialization on one side and distalization on the contralateral side) with the aid of Mesial-Distalslider. Dental casts were taken for each patient before (T0) and after the treatment (T1). The casts were 3D digitized and the models were superimposed on the palatal anterior region. Three-dimensional molar movements and sagittal incisor movements (proclination and retroclination) were assessed for T0 and T1. RESULTS: At the end of the treatment, the total movements of the molars resulted in 4.5 ± 2.2 mm (antero-posterior direction), -0.4 ± 2.4 mm (transverse direction) and 0.3 ± 0.9 mm (vertical direction) on the mesialization side, and -2.4 ± 1.7 mm (antero-posterior direction), -0.5 ± 1.5 mm (transverse direction) and 0.2 ± 1.4 mm (vertical direction) on the distalization side. Incisor displacement was 0.9 mm ± 1.7 (mesialization side) and 0.6 mm ± 0.7 (distalization side). CONCLUSION: The Mesial-Distalslider appliance could be considered a valuable tool in orthodontic treatment for upper midline correction. Within the limits of a retrospective study, asymmetric molar movements appeared possible without clinically relevant anchorage loss.

Dentoskeletal effects of mini-screw assisted, non-surgical palatal expansion in adults using a modified force-controlled polycyclic protocol: a single-centre retrospective study.

OBJECTIVES: This study assessed the dental and skeletal effects of pure bone-borne, non-surgical maxillary expansion, using a modified force-controlled polycyclic protocol. METHODS: Records of 17 adult patients, mean age 24.1 years; range 18-39 years, who had undergone maxillary expansion using a bone-borne Quad-expander (with 4 mini-screws), were analysed. In all patients, 0.17 mm/day of expansion was completed for 1 week, followed by a cyclic protocol of expansion of forward and backward turns until the force needed to turn the expander was below 400 cN, assessed weekly. After this, expansion continued at a rate of 0.17 mm/day until the desired amount of expansion was achieved. Cone beam computer tomography scans were taken pre- and post-expansion. RESULTS: The mid-palatal suture was successfully opened in 100% of patients included in this study. Axially, the amount of skeletal opening at the posterior nasal spine was 61% of the anterior nasal spine. Expansion was pyramidal in the coronal plane. Significant increases at the dental and skeletal levels were achieved, with changes at the skeletal level reaching 73%. The alveolar bone angle increased more than the angular changes at the molars and premolars. LIMITATIONS: This is a retrospective study with short-term results. CONCLUSION: The Quad-expander, with a force-controlled polycyclic expansion protocol, effectively produced a significant increase in maxillary width in skeletally mature subjects in the short term.

Dentofacial effects of miniscrew-anchored maxillary protraction on prepubertal children with maxillary deficiency: a randomized controlled trial.

BACKGROUND: The introduction of bone-anchored maxillary protraction eliminated the side effects of facemask in the early treatment of patients with maxillary retrusion. This study aimed to evaluate the effects of miniscrew-anchored maxillary protraction (MAMP) and compare them with the growth changes in an untreated control group in growing patients with Class III malocclusion. METHODS: Forty growing patients with Class III malocclusion and retrognathic maxilla were randomly allocated into two groups: treated and control groups. In the treated group, patients were treated with full-time intermaxillary Class III elastics (C3E) anchored by a hybrid hyrax (HH) in the maxilla and a bone-supported bar in the mandible. Protraction was stopped after obtaining a positive overjet. Cephalometric radiographs were acquired before and after the treatment. Data were statistically analyzed on an intention-to-treat basis. Intergroup comparisons were also made using analysis of covariance with the readings at T0 as a covariate. RESULTS: Forty patients agreed to participate, and 30 of them completed the study (treated group, n = 17; control group, n = 13). The average treatment duration was 11.9 months. MAMP resulted in a significant maxillary advancement (A-VR, 4.34 mm) with significant control over the mandibular growth. No significant increase in the mandibular plane angle was found in the treated group compared with the control group. The upper and lower incisors showed significant protrusion in the treated group. CONCLUSIONS: Within the limitations of this study and high attrition rate, the MAMP protocol can effectively increase maxillary forward growth with good control over the growth of the mandible antero-posteriorly and vertically.

Customized adjuncts with clear aligner therapy: "The Golden Circle Model" explained!

Clear aligners are the most debated infusion of technology into the orthodontic stratosphere and currently account for a sizable chunk of the orthodontic commercial market. Data indicate that a series of plastic aligners alone cannot resolve all the variants of malocclusion routinely treated by our specialty. Current literary consensus exists that the discrepancy between the predicted and actual clinical outcomes with clear aligner therapy (CAT) is around 50% or more, necessitating midcourse corrections, refinement, or additional aligners, or even a conversion to fixed appliances before the end of treatment. A practical panacea to improve the predictability of CAT is the addition of creative and customized adjuncts to CAT. This article, inspired by the "Golden Circle Model", addresses questions such as the "WHY, HOW, and WHAT" of adjuncts used in combination with CAT and depicts an "inside out" approach (from WHY to WHAT) to present the rationale, stepwise clinical workflow, and the advantages of these adjuncts. The bootstrap, mini pin-supported mesialization or distalization, Yin-Yang attachments, Beneslider, Mesialslider, BMX Expander, and Computer-Aided Design (CAD) / Computer-Aided-Manufacturing (CAM)...based innovative appliance designs among others, are presented as adjuncts to CAT in this article. These adjuncts can either be used concomitantly with the aligners or planned as a separate phase of treatment before the commencement of the actual CAT, based on the type of tooth movement required and whether the planned tooth movement is indicated for a single tooth or a group of teeth. An astute clinician who wishes to expand the repertoire of malocclusions that can be successfully managed by CAT should judiciously plan the inclusion of such adjunct appliances in their aligner treatment planning.

Maxillary space closure using a digital manufactured Mesialslider in a single appointment workflow.

New digital technologies, many involving three-dimensional printing, bring benefits for clinical applications. This article reports on the clinical procedure and fabrication of a skeletally anchored mesialization appliance (Mesialslider) using computer-aided design/computer-aided manufacturing (CAD/CAM) for space closure of a congenitally missing lateral incisor in a 12-year-old female patient. The insertion of the mini-implants and appliance was performed in a single appointment. Bodily movement of the molars was achieved using the Mesialslider. Anchorage loss, such as deviation of the anterior midline or palatal tilting of the anterior teeth, was completely avoided. CAD/CAM facilitates safe and precise insertion of mini-implants. Further, mini-implants can improve patient comfort by reducing the number of office visits and eliminating the need for orthodontic bands and physical impressions.

Procedure using CAD/CAM-manufactured insertion guides for purely mini-implant-borne rapid maxillary expanders.

With traditional rapid palatal expansion (RPE), orthopaedic forces are transmitted to the skeletal structures via the anchor teeth potentially leading to several unwanted dental side effects. To prevent these issues, tooth-bone-borne or purely bone-borne expanders were introduced using mini-implants in the palate. In this paper, the digitally planned Quadexpander is described which permits palatal expansion with only skeletal anchorage. The use of virtual insertion planning allows for insertion in areas of ideal bone, while avoiding roots and vital structures as well as the possibility of insertion into sites which would otherwise not be considered usable. A second advantage of digital planning is that mini-implants and the expander can be inserted in just one appointment.

Dentoskeletal changes due to rapid maxillary expansion in growing patients with tooth-borne and tooth-bone-borne expanders: A randomized clinical trial.

OBJECTIVES: To compare, using cone-beam computed tomography, the dentoskeletal changes in rapid maxillary expansion with tooth-bone-borne (Hybrid Hyrax) and tooth-borne (Hyrax) appliances. SETTING AND SAMPLE POPULATION: Forty-two patients who met the eligibility criteria (aged 11-14 years; transverse maxillary deficiency, posterior crossbite, and presence of upper first premolars and molars) were screened and allocated into two groups: HHG (treatment with Hybrid Hyrax) and HG (treatment with Hyrax). MAIN OUTCOME MEASURES: The primary outcomes included nasomaxillary dimensional changes. CBCT was performed before and 3 months after the activation phase. Measurements were performed using Dolphin® . Baseline data were compared using one-way ANOVA. For intergroup comparison, ANCOVA was used to analyze the initial age, appliance activations (mm), and mid-palatal suture maturation data as covariates. Statistical significance was set at 5%. RESULTS: The premolar region in HHG showed increased skeletal changes than in HG, with the difference being 1.5 mm (0.5; 2.6) in the nasal cavity (P = .004), 1.4 mm (0.3; 2.5) in the nasal floor (P = .019), and 1.1 mm (0.2; 2.1) in the maxilla (P = .022). The molar region in HHG showed increased skeletal changes with the difference being 0.9 mm (0.2; 1.5) in the nasal cavity (P = .005), and 0.9 mm (0; 1.8) in the maxilla (P = .042) than in HG. Premolar inclination was higher in HG. CONCLUSION: Hybrid Hyrax showed more skeletal changes and fewer dental side effects, especially in the first premolar region. The amount of activation influenced the higher nasal skeletal changes in the Hybrid hyrax group.

Treatment of maxillary transversal deficiency by using a mini-implant-borne rapid maxillary expander and aligners in combination.

Bone-borne rapid maxillary expansion distraction devices are used to achieve a more skeletal expansion and to avoid dental side effects of conventional expanders such as tipping of anchorage teeth. In this article, we report the use of a prefabricated expander fixed on 2 mini-implants in the anterior palate. This allows for the insertion of the mini-implants and the expander to occur without the need for an impression or any laboratory procedures. Especially when aligners are going to be used, the use of a mini-implant-borne expander seems to be reasonable because the expander can be left in place as a skeletal retainer during the aligner finishing.

Is there an ideal insertion angle and position for orthodontic mini-implants in the anterior palate? A CBCT study in humans.

INTRODUCTION: Orthodontic mini-implants are frequently used to provide additional anchorage for orthodontic appliances. The anterior palate is frequently used owing to sufficient bone quality and low risk of iatrogenic trauma to adjacent anatomical structures. Even though the success rates in this site are high, failure of an implant will result in anchorage loss. Therefore, implants should be placed in areas with sufficient bone quality. The aim of the present study was to identify an optimal insertion angle and position for orthodontic mini-implants in the anterior palate. METHODS: Maxillary cone-beam computed tomographic (CBCT) scans from 30 patients (8 male, 22 female, age 18.6 ± 12.0 years) were analyzed. To assess the maximum possible length of an implant, a 25-reference-point grid was defined: 5 sagittal slices were extracted along the median plane and bilaterally at 3 mm and 6 mm distances, respectively. Within each slice, 5 dental reference points were projected to the palatal curvature at the contact point between the cuspid (C) and first bicuspid (PM1), midpoint of PM1, between PM1 and PM2, midpoint of PM2, and between PM2 and the first molar (M1). Measurements were conducted at -30°, -20°, -10°, 0°, 10°, 20°, and 30° to a vector placed perpendicular to the local palatal curvature. Statistical analysis was conducted with the use of R using a random-effects mixed linear model and a Tukey post hoc test with Holm correction. RESULTS: High interindividual variability was detected. Maximum effective bone heights were detected within a T-shaped area at the midpoint of PM1 and contact point PM1-PM2 (P < 0.01). Within the anterior region a posterior tipping was advantageous, whereas in the posterior regions an anterior tipping was beneficial (P < 0.01). In the middle of the median plane, tipping did not reveal a significant influence. No gender- or age-related differences were observed. CONCLUSIONS: Within the limitations of this study, optimal insertion positions were found within a T-shaped area at the height of PM1-PM2 in the anterior palate. In general, a posterior tipping was beneficial at anterior positions, and an anterior tipping appeared beneficial at posterior positions. High interindividual variation was found and should be carefully considered by the clinician.

CAD-CAM-fabricated mini-implant insertion guides for the delivery of a distalization appliance in a single appointment.

This article reports on the technical aspects of using a computer-aided design-computer-aided manufacturing (CAD-CAM) insertion guide for the placement of orthodontic mini-implants used for the purpose of providing anchorage support for maxillary molar distalization. A 10-year-old girl presented with a bilateral full-step Angle Class II molar relationship in the permanent dentition, with anterior arch-length insufficiency and blocked out maxillary canine teeth. The primary treatment objective was to provide an esthetic and functional occlusal outcome, and secondarily to avoid the removal of multiple premolar teeth. The patient was initially treated with an implant-supported distalization device, and the occlusion was subsequently detailed with preadjusted fixed orthodontic appliances. The CAD-CAM procedure facilitates the safe and precise insertion of mini-implants in the anterior palate, potentially broadening the scope of use of palatal mini-implants for less experienced clinicians. The illustrated protocol allows for the insertion of mini-implants and fitting of a prefabricated appliance in a single office appointment.

Maxillary molar mesialization with the use of palatal mini-implants for direct anchorage in an adolescent patient.

A unique clinical challenge presents when dealing with a compromised first permanent molar. A compelling treatment option for consideration is the removal of a nonrestorable first permanent molar, with the subsequent "replacement" through controlled mesial tooth movement of viable second and third molars. To reinforce the anchorage support associated with such a planned movement, indirect or direct implant-supported mechanics may be used. With the use of direct anchorage, orthodontic brackets are not required and space closure can be commenced immediately. In this article, we report the clinical procedure and design of direct-anchorage mechanics used for the successful closure of a maxillary first permanent molar space with the use of an implant-supported appliance (Mesialslider). Treatment was completed in just under 12 months, with successful mesial movement of the maxillary second and third molars without the need for the bonding of orthodontic brackets on the anterior dentition. The result was determined to be stable over a 3-year period.