Lingual treatment of an adult patient with an iatrogenic class II anterior open bite: Report of a case with a non-surgical orthodontic approach.

INTRODUCTION: The treatment of adult patients presenting an open bite is a real challenge for orthodontists due to the complexity of the malocclusion. The diagnosis is essential to identify aetiological factors and establish the best aesthetic and functional therapeutic prognosis. Among the aetiological factors, iatrogenic treatment history has to be considered. It is the case here where a regrettable unsuitable splint for bruxism treatment forced an open bite to appear. MATERIAL AND METHOD: This case report presents an adult women with a large open bite due to an occlusal splint not covering the last mandibular molars. It was not really a vertical skeletal excess but more a mandibular clockwise rotation linked to the molar extrusions, which created a dento-alveolar open bite and labio-mental contractions during lip closure. Treatment objectives were the intrusion of the third and second molars, the extrusion of incisors to obtain a counter clockwise mandibular rotation. The patient was treated with an aesthetic and customized lingual appliance with no orthognathic surgery. A physiotherapy was followed by the patient when the open bite was closed in order to facilitate and stabilize the intercuspation. RESULTS: A complete closing of the open bite was reached after two years of treatment. The superimposition showed the anticlockwise mandibular rotation. The levelling with posterior intrusion and the incisors extrusion reduced the vertical dimension with success. After 3years of retention, the occlusal stability was obtained. CONCLUSION: The intrusion of the molars associated with a counter clockwise mandibular rotation made it possible the incisor extrusion. The occlusal balance with physiotherapy and patient compliance maintained the closure. In this way, the iatrogenic effects of the poorly designed bite splint were repaired.

Evaluation of the efficiency of various force configurations on scoliotic, lordotic and kyphotic curves in the subjects with scoliosis.

BACKGROUND: The efficiency of the braces designed for scoliotic subjects depends on configurations and also magnitudes of the forces used to stabilize and correct scoliotic curve. However, the effects of various force configurations on the spinal curves in sagittal plane should also be considered. The aim of this study was to determine the efficiency of various force configurations on scoliotic, lordotic and kyphotic curves. METHOD: A 3d model of spine was developed based on CT scan images of spine obtained from a scoliotic girl. The model was exported to Abaqus software to check the effects of various force configurations and magnitudes on spinal curves. The spinal curves in thoracic and lumbar, lordotic and kyphotic curves were evaluated in this study. Transverse forces, vertical forces and combination of transverse and vertical forces were selected in this study. RESULTS: The results of this study showed that use of transverse forces did not influence the scoliotic curve significantly. Vertical directed forces not only decreased scoliotic curves but also decreased lordotic and kyphotic curves. It seems that a combination of both transverse and vertical directed forces decreased scoliotic curves but did not influence spinal curves in sagittal plane. CONCLUSION: It is recommended to use a combination of transverse and vertical forces to decrease scoliotic curve without significant side effects on the spinal curves in sagittal plane. As this is a case study the outputs of the study should be used with caution.

Correction of Class III malocclusions through morphological changes of the maxilla using the protraction face mask by three different therapeutic approaches.

Face mask (FM) therapy used for maxillary protraction improves the facial profile in patients with Class III malocclusion. The aim of this study was to compare the sagittal morphological changes of the maxilla through three different therapeutic approaches, respectively using removable appliances (RA), rapid maxillary expansion (RME) and surgically assisted rapid maxillary expansion (SARME), each of them in combination with the FM therapy in growing and non-growing patients. The sample, consisting of 42 orthodontic patients aged 7-21, was divided into four groups, according to their age. The first group of patients, aged 6-9 (RA + FM group), received treatment with RA in combination with FM, the second group of patients, aged 10-13 (RME + FM pubertal group), received treatment with RME in combination with FM, the third group of patients, aged 14-16 (RME + FM postpubertal group), received treatment with RME and FM, and the fourth group of patients, aged 17-21 (SARME + FM group), underwent SARME in combination with FM. To assess the sagittal skeletal changes of the maxilla, the sella-nasion-A point (SNA) and A point-nasion-B point (ANB) angles were measured at the beginning and after the FM therapy. The differences in the evolution of the SNA angle between the groups were statistically significant (p<0.001). Post-hoc analysis showed that patients aged 6-9 had the highest evolution, statistically higher than patients aged 14-16 (p=0.007) or patients aged 17-21 (p<0.001). The evolution of the SNA angle was significantly higher in patients aged 10-13, in comparison to patients aged 17-21 (p<0.001). The efficiency of the FM therapy alone or associated with RME depends on patients' growing period. In non-growing patients, the FM therapy is efficient when associated with SARME.

Multidisciplinary treatment with a customized lingual appliance for an adult patient with severe Class III malocclusion and multiple missing teeth.

A 24-year-old man presented with a severe skeletal class III malocclusion, associated with an anterior and posterior crossbite in the left side, upper and lower lip eversion, skeletal asymmetry, midline discrepancy, diastemas in the maxillary and mandibular dental arches, and agenesis of maxillary lateral incisors and canines with retained deciduous teeth. Treatment was performed with the use of the Win Lingual System. When the 0.016 × 0.022-inch NiTi archiwire was applied, the deciduous teeth were extracted and replaced with temporary crowns connected to the appliance. After the aligning, leveling, and diastema closure phases, a modified Le Fort II osteotomy, a mandibular setback with a bilateral sagittal split osteotomy and a genioplasty were performed. Implants were placed in the canine site through a flapless guided surgery, and cantilevered temporary bridges were delivered. Final prosthetic rehabilitation included veneers for the central incisors and zirconia-ceramic cantilevered bridges for the canine and lateral incisors. After 36 months of active treatment, the patient showed an Angle Class I molar and canine relationship and an ideal overbite and overjet. His profile had improved, lips were competent, and gingival levels were acceptable. The lateral radiograph and cephalometric analysis showed a good balance of the skeletal pattern, a good profile of the soft tissue, and proper inclinations of the maxillary and mandibular incisors in relation to maxilla and mandible. After 2 years of follow-up, the patient had a pleasant smile and no relapse, or joint or muscular pain.

Effects of size and insertion angle of orthodontic mini-implants on skeletal anchorage.

INTRODUCTION: The primary aim of this in vitro study was to compare the insertion torque (IT) and anchorage force (AF) values of 4 different sizes of orthodontic mini-implants with 2 different angles. The second aim was to evaluate the relationship between IT and AF values under different diameter, length, and insertion angle variables. METHODS: A total of 160 mini-implants, including 20 implants in each group, with 4 different sizes (1.6 × 8 mm, 1.6 × 10 mm, 2.0 × 8 mm, and 2.0 × 10 mm) at 2 different angles (70° and 90°), were inserted into bovine iliac bone segments. The IT and AF values leading to 1.5 mm deflection were compared. The correlations between IT and AF values under different variables were also analyzed. RESULTS: The mini-implants with greater diameter and length showed greater IT and AF values (P <0.05). The IT and AF values of mini-implants inserted at 70° angle were significantly greater than those of mini-implants inserted at 90° angle (P <0.001). Significant correlations were found between IT and AF values in all variables. CONCLUSIONS: The diameter, length, and insertion angle of orthodontic mini-implants have significant effects on IT and AF values. Insertion angle and diameter of mini-implants are more effective than implant length on skeletal anchorage. Significant correlations are present between IT and AF values of mini-implants regardless of their diameters, lengths, and insertion angles.

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.

Evaluation of fit for 3D-printed retainers compared with thermoform retainers.

INTRODUCTION: In the literature, there is little information available on 3D-printed orthodontic retainers. This study examined the accuracy of 3D-printed retainers compared with conventional vacuum-formed and commercially available vacuum-formed retainers. METHODS: Three reference models (models 1, 2, and 3) were used to fabricate traditional vacuum-formed, commercially available vacuum-formed, and 3D-printed retainers. For each model, retainers were made using the 3 methods (a total of 27 retainers). To determine the trueness, ie, closeness of a model to a true model, the distance between the retainer and its digital model at reference points were calculated with the use of engineering software. The measurements were reported as average absolute observed values and compared with those of the conventional vacuum-formed retainers. RESULTS: Average differences of the conventional vacuum-formed retainers ranged from 0.10 to 0.20 mm. The commercially available and 3D-printed retainers had ranges of 0.10 to 0.30 mm and 0.10 to 0.40 mm, respectively. CONCLUSIONS: The conventional vacuum-formed retainers showed the least amount of deviation from the original reference models and the 3D-printed retainers showed the greatest deviation. However, all 3 methods yielded measurements within 0.5 mm, which has previously been accepted to be clinically sufficient.

[Archwire segmentation: a solution to the problems involved in treating atypical cases]. / La segmentation de l'arc, une réponse aux difficultés de traitement de cas atypiques.

INTRODUCTION: Asymmetrical orthodontic cases frequently prove very difficult to correct. Anchorage mini-screws are often needed to treat these cases when the malocclusion is of maxillary origin. Nonetheless, a precise biomechanical assessment must be made to avoid undesirable sideeffects resulting from the mechanics used. Whether one uses a continuous or a segmented archwire, adverse events can occur and must be planned for in order to contain them. MATERIALS AND METHODS: The authors will first give an overview of the possible undesirable effects using the continuous arch technique and the principles underlying the segmented archwire technique. Various clinical cases will also be described to support their argument. CONCLUSION: The advantage of the segmented techniques lies in the precision and speed of the movements obtained in the three dimensions of space. However, they can also present major drawbacks. In practice, these techniques seem best-suited to complex atypical cases, and particularly cases involving asymmetry of the frontal and transverse planes.

Electromyographic evaluation in children orthodontically treated for skeletal Class II malocclusion: Comparison of two treatment techniques.

OBJECTIVE: To compare the clinical efficacy of two techniques for fabricating a Bimler device by assessing the patient's surface electromyography (sEMG) activity at rest before treatment and six months after treatment. METHODS: Twenty-four patients undergoing orthodontic treatment were enrolled in the study; 12 formed the test group and wore a Bimler device fabricated with a Myoprint impression using neuromuscular orthodontic technique and 12 formed the control group and were treated by traditional orthodontic technique with a wax bite in protrusion. The "rest" sEMG of each patient was recorded prior to treatment and six months after treatment. RESULTS: The neuromuscular-designed Bimler device was more comfortable and provided better treatment results than the traditional Bimler device. CONCLUSION: This study suggests that the patient group subjected to neuromuscular orthodontic treatment had a treatment outcome with more relaxed masticatory muscles and better function versus the traditional orthodontic treatment.

Treatment of class II malocclussion: A comparative study of the effects of twin-block and fatigue resistant device.

AIM: This is a retrospective cephalometric study aimed to compare the treatment effects of Twin-Block (TB) appliance with The Forsus Fatigue Resistant Device (FRD) appliance in class II division I patients in a composite of peak and post peak growth of period time. MATERIALS AND METHODS: The experimental sample consisted of the lateral cephalograms of 40 patients who were treated with either TB appliance (n = 15), FRD (n = 15) or the untreated control ones. In treatment groups lateral cephalograms taken before therapy as initial records (T1) and at the completion of functional therapy (T2) were used. The control group comprised 10 children with untreated skeletal Class II malocclusions. The normality of distribution of continuous variables was tested by Shaphiro wilk test. Oneway ANOVA and LSD test in parametric; Kruskall Wallis and all pairwaise multible comparison tests in non-parametric samples were used for comparing differences among 3 groups. RESULTS: Cephalometric analysis revealed that both TB and FRD appliances stimulated mandibular growth (P < 0.05) and no restriction was seen in maxilla in both groups (P > 0.05). The unwanted mandibular proclination was seen more in FRD group (P ≤ 0.001). Soft tissue didn't imitate the hard tissue (P > 0.05). CONCLUSION: FRD group produced skeletal effects as much as TB group in peak and post peak period of growth with still more mandibular incisor proclination.

Evaluation of Long-term Stability of Vertical Control in Hyperdivergent Patients Treated with Temporary Anchorage Devices.

This study aims to evaluate the long-term stability of vertical control in hyperdivergent patients treated with temporary anchorage devices. The sample included 20 hyperdivergent patients without anterior open bite. The temporary anchorage devices were used to intrude the upper incisor and molars for vertical control. Lateral cephalograms were established prior to treatment, immediately after treatment, and during retention. The upper molars and incisors were intruded by 1.33 mm and 1.41 mm after treatment (P<0.05). U6-PP increased by 0.11 mm and 0.23 mm during the first and second stages of retention (P>0.05). U1-PP was found to possess a significant extrusion of 1.2 mm during the first stage (P<0.05), which increased by 0.68 mm during the second stage (P>0.05). The mandibular plane angle (MP-SN) decreased by 2.58 degrees following treatment, and underwent a relapse of 0.51 degree and 0.42 degree during the first and second stages of retention respectively (P>0.05). No significant soft tissue changes occurred, with the exception of increased upper lip length during the second stage (P<0.05). Maxillary anterior and posterior intrusions, counter clockwise rotation of the mandibular plane, and improved profiles can be successfully achieved following treatment with vertical control. During the first stage of retention (less than three years), intruded molars and incisors both exhibited some extrusion, and molars had better long-term stability than incisors. During the second stage of retention (three to six years), the therapeutic effects appeared stable, with the exception of some increase in upper lip length. Rotated mandibular plane remained stable during the entire retention period.

[Possibilities and limitations of treatment with clear aligners. An orientation]. / Mogelijkheden en beperkingen van orthodontische behandeling met clear aligners. Een verkenning.

The aim of this research was to evaluate the efficiency and effectiveness of an orthodontic treatment with clear-aligner systems, specifically with Invisalign®. In addition to a review of the literature, 4 orthodontists and 9 patients treated with fixed orthodontic therapy and Invisalign® were interviewed. The literature showed that it is difficult to correct an extrusion, rotation or overjet with clear aligners. Often 'refinement' (additional intervention during treatment) is necessary to achieve the best possible end result. The patients interviewed experienced few limitations in their daily lives caused by the clear aligners and hardly any pain. Treatment duration was comparable to that with fixed appliances; it depended on the experience of the orthodontist, the complexity of the case and cooperation of the patient. The cost of an Invisalign® treatment is higher than that of fixed-appliance therapy. Additionally, making a plan for clear-aligner treatment often takes more time for the orthodontist than planning treatment for fixed-appliance therapy.

Force System with Vertical V-Bends: A 3D In Vitro Assessment of Elastic and Rigid Rectangular Archwires.

A proper understanding of the force system created by various orthodontic appliances can make treatment of patients efficient and predictable. Reducing the complicated multi-bracket appliances to a simple two-bracket system for the purpose of force system evaluation will be the first step in this direction. However, much of the orthodontic biomechanics in this regard is confined to 2D experimental studies, computer modeling/analysis or theoretical extrapolation of existing models. The objective of this protocol is to design, construct and validate an in vitro 3D model capable of measuring the forces and moments generated by an archwire with a V-bend placed between two brackets. Additional objectives are to compare the force system generated by different types of archwires among themselves and to previous models. For this purpose, a 2 x 4 appliance representing a molar and an incisor has been simulated. An orthodontic wire tester (OWT) is constructed consisting of two multi-axis force transducers or load cells (nanosensors) to which the orthodontic brackets are attached. The load cells are capable of measuring the force system in all the three planes of space. Two types of archwires, stainless-steel and beta-titanium of three different sizes (0.016 x 0.022 inch, 0.017 x 0.025 inch and 0.019 x 0.025 inch), are tested. Each wire receives a single vertical V-bend systematically placed at a specific position with a predefined angle. Similar V-bends are replicated on different archwires at 11 different locations between the molar and incisor attachments. This is the first time an attempt has been made in vitro to simulate an orthodontic appliance utilizing V-bends on different archwires.

Expanding torque possibilities: A skeletally anchored torqued cantilever for uprighting "kissing molars".

Several uprighting mechanics and devices have been used for repositioning tipped molars. "Kissing molars" (KMs) are an uncommon tooth impaction involving 2 severely tipped mandibular molars with their occlusal surfaces positioned crown to crown, with the roots pointing in opposite directions. Orthodontic uprighting of KMs has not been a usual treatment protocol, and it can be a challenging task due to the severe tipping and double impaction, requiring efficient and well-controlled uprighting mechanics. An innovative skeletally anchored cantilever, which uses the torque principle for uprighting tipped molars, is suggested. This torqued cantilever is easy to manufacture, install, and activate; it is a well-known torque that is effective for producing root movement. A successful treatment of symptomatic KMs, involving the first and second molars, was achieved with this cantilever. Thus, clinicians should consider the suggested uprighting mechanics and orthodontic device as a more conservative alternative to extraction of KMs, depending on the patient's age, involved teeth in KMs, tipping severity, and impaction positions.

Comparison of deflection forces of esthetic archwires combined with ceramic brackets.

Coated archwires and ceramic brackets have been developed to improve facial esthetics during orthodontic treatment. However, their mechanical behavior has been shown to be different from metallic archwires and brackets. Therefore, the aim of this study was to compare the deflection forces in coated nickel-titanium (NiTi) and esthetic archwires combined with ceramic brackets. Material and Methods Non-coated NiTi (NC), rhodium coated NiTi (RC), teflon coated NiTi (TC), epoxy coated NiTi (EC), fiber-reinforced polymer (FRP), and the three different conventional brackets metal-insert polycrystalline ceramic (MI-PC), polycrystalline ceramic (PC) and monocrystalline ceramic (MC) were used. The specimens were set up on a clinical simulation device and evaluated in a Universal Testing Machine (Instron). An acrylic device, representative of the right maxillary central incisor was buccolingually activated and the unloading forces generated were recorded at 3, 2, 1 and 0.5 mm. The speed of the testing machine was 2 mm/min. ANOVA and Tukey tests were used to compare the different archwires and brackets. Results The brackets presented the following decreasing force ranking: monocrystalline, polycrystalline and polycrystalline metal-insert. The decreasing force ranking of the archwires was: rhodium coated NiTi (RC), non-coated NiTi (NC), teflon coated NiTi (TC), epoxy coated NiTi (EC) and fiber-reinforced polymer (FRP). At 3 mm of unloading the FRP archwire had a plastic deformation and produced an extremely low force in 2; 1 and 0.5 mm of unloading. Conclusion Combinations of the evaluated archwires and brackets will produce a force ranking proportional to the combination of their individual force rankings.

Qualitative assessment of awake nasopharyngoscopy for prediction of oral appliance treatment response in obstructive sleep apnoea.

PURPOSE: Clinical methods to identify responders to oral appliance (OA) therapy for obstructive sleep apnoea (OSA) are needed. Awake nasopharyngoscopy during mandibular advancement, with image capture and subsequent processing and analysis, may predict treatment response. A qualitative assessment of awake nasopharyngoscopy would be simpler for clinical practice. We aimed to determine if a qualitative classification system of nasopharyngoscopic observations reflects treatment response. METHODS: OSA patients were recruited for treatment with a customised two-piece OA. A custom scoring sheet was used to record observations of the pharyngeal airway (velopharynx, oropharynx, hypopharynx) during supine nasopharyngoscopy in response to mandibular advancement and performance of the Müller manoeuvre. Qualitative scores for degree (< 25%, 25-50%, 50-75%, > 75%), collapse pattern (concentric, anteroposterior, lateral) and diameter change (uniform, anteroposterior, lateral) were recorded. Treatment outcome was confirmed by polysomnography after a titration period of 14.6 ± 9.8 weeks. Treatment response was defined as (1) Treatment AHI < 5, (2) Treatment AHI < 10 plus > 50% AHI reduction and (3) > 50% AHI reduction. RESULTS: Eighty OSA patients (53.8% male) underwent nasopharyngoscopy. The most common naspharyngoscopic observation with mandibular advancement was a small (< 50%) increase in velopharyngeal lateral diameter (37.5%). The majority of subjects (72.5%) were recorded as having > 75% velopharyngeal collapse on performance of the Müller manoeuvre. Mandibular advancement reduced the observed level of pharyngeal collapse at all three pharyngeal regions (p < 0.001). None of the nasopharyngoscopic qualitative scores differed between responder and non-responder groups. CONCLUSION: Qualitative assessment of awake nasopharyngoscopy appears useful for assessing the effect of mandibular advancement on upper airway collapsibility. However, it is not sensitive enough to predict oral appliance treatment outcome.

Titration technique using endoscopy for an oral appliance treatment of obstructive sleep apnea.

The degree of mandibular protrusion for an oral appliance (OA) should be customized for each patient with obstructive sleep apnea (OSA). This article describes the mandibular titration technique for OAs to effectively treat OSA by using endoscopy to evaluate the change in the airway at the velopharynx. This technique may minimize the degree of mandible protrusion and contribute to both the efficacy of and compliance with OA therapy.

Comparison of deflection forces of esthetic archwires combined with ceramic brackets

Abstract Coated archwires and ceramic brackets have been developed to improve facial esthetics during orthodontic treatment. However, their mechanical behavior has been shown to be different from metallic archwires and brackets. Therefore, the aim of this study was to compare the deflection forces in coated nickel-titanium (NiTi) and esthetic archwires combined with ceramic brackets. Material and Methods Non-coated NiTi (NC), rhodium coated NiTi (RC), teflon coated NiTi (TC), epoxy coated NiTi (EC), fiber-reinforced polymer (FRP), and the three different conventional brackets metal-insert polycrystalline ceramic (MI-PC), polycrystalline ceramic (PC) and monocrystalline ceramic (MC) were used. The specimens were set up on a clinical simulation device and evaluated in a Universal Testing Machine (Instron). An acrylic device, representative of the right maxillary central incisor was buccolingually activated and the unloading forces generated were recorded at 3, 2, 1 and 0.5 mm. The speed of the testing machine was 2 mm/min. ANOVA and Tukey tests were used to compare the different archwires and brackets. Results The brackets presented the following decreasing force ranking: monocrystalline, polycrystalline and polycrystalline metal-insert. The decreasing force ranking of the archwires was: rhodium coated NiTi (RC), non-coated NiTi (NC), teflon coated NiTi (TC), epoxy coated NiTi (EC) and fiber-reinforced polymer (FRP). At 3 mm of unloading the FRP archwire had a plastic deformation and produced an extremely low force in 2; 1 and 0.5 mm of unloading. Conclusion Combinations of the evaluated archwires and brackets will produce a force ranking proportional to the combination of their individual force rankings.

Biomechanical Effects of Various Bone-Implant Interfaces on the Stability of Orthodontic Miniscrews: A Finite Element Study.

INTRODUCTION: Osseointegration is required for prosthetic implant, but the various bone-implant interfaces of orthodontic miniscrews would be a great interest for the orthodontist. There is no clear consensus regarding the minimum amount of bone-implant osseointegration required for a stable miniscrew. The objective of this study was to investigate the influence of different bone-implant interfaces on the miniscrew and its surrounding tissue. METHODS: Using finite element analysis, an advanced approach representing the bone-implant interface is adopted herein, and different degrees of bone-implant osseointegration were implemented in the FE models. A total of 26 different FE analyses were performed. The stress/strain patterns were calculated and compared, and the displacement of miniscrews was also evaluated. RESULTS: The stress/strain distributions are changing with the various bone-implant interfaces. In the scenario of 0% osseointegration, a rather homogeneous distribution was predicted. After 15% osseointegration, the stress/strains were gradually concentrated on the cortical bone region. The miniscrew experienced the largest displacement under the no osseointegra condition. The maximum displacement decreases sharply from 0% to 3% and tends to become stable. CONCLUSION: From a biomechanical perspective, it can be suggested that orthodontic loading could be applied on miniscrews after about 15% osseointegration without any loss of stability.