Unilateral Brodie bite treated with distraction osteogenesis

Measurement and analysis of condylar morphology and thickness of the roof of the glenoid fossa in patients with unilateral second molar scissor bite

Objective The objective of this study was to measure and analyze the joint space, condylar morphology, and thickness of the roof of the glenoid fossa (RGF) in patients with unilateral second molar scissor bite using cone beam CT (CBCT). Methods A total of 80 patients were included in this study. Forty patients with a normal posterior occlusal relationship, who attended the Department of Orthodontics at the First Hospital of Shanxi Medical University from December 2021 to August 2023, were selected as the control group. The experimental group consisted of 40 patients with unilateral second molar scissor bite during the same period. All patients underwent CBCT scanning, and the resulting images were analyzed using the NNT viewer software in multiplanar reconstruction (MPR). Axial, coronal, and sagittal adjustments were made for each patient. Results In the control group, the right and left joint spaces (PS, SS, AS), the height of the upper part of the condyle, and the depth of the glenoid fossa did not show statistically significant differences (P > 0.05). When comparing bilateral condylar morphology and joint space in the experimental group, it was found that the posterior joint space on the scissor bite side was greater than that on the normal occlusion side, while the anterior joint space on the scissor bite side was smaller than that on the normal occlusal side. Additionally, the height of the upper condyle and the depth of the glenoid fossa on the scissor bite side were greater than that on the normal occlusal side, with statistically significant differences (P < 0.05). However, there were no statistically significant differences in SS, internal and external joint diameter, as well as anterior and posterior diameters (P > 0.05). The comparison of the minimum thickness of the roof of the glenoid fossa in both the sagittal and coronal directions between the patients in the experimental group and the control group showed no statistically significant difference (P > 0.05). Furthermore, the asymmetry index of the supracondylar height in the control group was significantly smaller than that in the experimental group, displaying a statistically significant difference (P < 0.05). The differences in the asymmetry indices of the anterior and posterior diameters of the condyle, as well as the inner and outer diameters, were not statistically significant (P > 0.05). When analyzing the position of the condyle in the sagittal direction of the glenoid fossa in the patients of the control group, it was observed that the majority were in the anterior and medial positions, with only 10% and 5% being in the posterior position. However, the analysis of the condyle position in the sagittal direction of the glenoid fossa in the experimental group revealed statistically significant differences (P < 0.05), with the condyle position on the scissor bite side being more anterior. Conclusion Unilateral second molar scissor bite can result in anterior displacement of the condyle, greater height of the condyle superiorly as well as the depth of the glenoid fossa.

Clear Aligners and Miniscrews in a Scissor Bite Adult Treatment

Scissor bite does not correct spontaneously. It gradually worsens by overeruption, negatively affecting masticatory function. It is intended with this manuscript to evaluate the different treatment strategies to correct this malocclusion in adult patients, exploring treatment with clear aligners, bite ramps, and MS (miniscrews), especially in this case of a patient with unilateral right scissor bite, with high dental compensation in the three planes of space, asymmetrical sagittal dental position, overeruption on the scissor bite condition, and a high mandibular arch constriction and maxillary expansion. A comprehensive literature research was performed from 2002 until March 2023. PubMed and BVS databases were used, with the following keywords: "scissor bite OR brodie bite" AND "malocclusion" AND "treatment OR correction OR therapeutics". Since correcting skeletal asymmetries after the growth completion is challenging, adult patient cases often involve a combined orthodontic-surgical approach. In the present clinical case, the severe limitations to decompensating tooth positions for a surgical treatment, with the necessity to perform lower asymmetric extraction and a must longer orthodontic treatment, were the major reasons to avoid the surgical approach, after the scissor bite correction. In spite of this, the efficiency of the clear aligners and auxiliaries like bite ramps, MS, and elastics in successfully correcting a complex scissor bite in an adult patient was demonstrated, with significant esthetic and functional commitment, demonstrated by the case reliability PAR (peer assessment rating) index.

Prevalence of Malocclusions in Down Syndrome Population: A Cross-Sectional Study

Background and Objectives: A higher prevalence of dental malocclusion has been suggested among individuals with Down Syndrome (DS) compared to controls, although no studies to date have investigated such a difference according to age group. Therefore, the aim of this study was to compare the prevalence of dental malocclusion and other orthodontic measures between DS and non-syndromic (non-DS) individuals across three age groups of children, adolescents, and adults. Materials and Methods: This cross-sectional study was conducted on a total of 147 patients. Of those, 72 were diagnosed with DS and were divided into N = 15 children (<10 years), N = 23 adolescents (10-18 years) and N = 34 adults (>18 years). The remaining 75 patients were sex- and age-matched controls. The two groups were compared according to age group in terms of the prevalence of dental malocclusion, measures of sagittal, vertical, and transverse discrepancy, facial profile, and probable sleep bruxism with chi-square tests for proportion. Results: The DS patients consistently exhibited a higher prevalence of Class 3 malocclusion, concave profile and anterior crossbite compared to the non-DS patients, regardless of age group. The non-DS adolescents presented with a significantly higher prevalence of convex profile than the DS adolescents. The adolescent and adult DS patients most commonly presented with a maxillary transverse discrepancy and posterior crossbite compared to the non-DS controls. The DS adults had a higher prevalence of probable sleep bruxism. Conclusions: Patients with DS showed a higher prevalence of Class 3 malocclusion, concave profile and anterior crossbite compared to non-DS controls, regardless of age group. Other orthodontic measures showed a fluctuation according to the age group considered.

Scissor Bite in Growing Patients: Case Report Treated with Clear Aligners

Scissor bite (SB.) is a rare malocclusion that is challenging to diagnose and is often associated with a retrognathic mandible and a series of functional and structural abnormalities that negatively affect the patient. This article intends to analyze the treatment approaches applied to growing patients younger than 16 years old, comparing the conventional appliances described in the literature and a clinical case treated with clear aligners with mandibular advancement (MA.). SB is primarily related to skeletal Class I and II, according to Angle classification. In the various cases analyzed, it can also be mentioned as a significant number of cases with SB of dental origin (seven of dental and four of skeletal) in young patients. In children and adolescents who still have growth potential, the therapeutic possibilities are numerous. A comprehensive literature search was manually performed from 2002 until January 2023, in PubMed and BVS databases with the following conjugated keywords: “scissor bite OR brodie bite” AND “malocclusion” AND “treatment OR correction OR therapeutics”. The present case report on a young patient demonstrated the efficiency of the clear aligners with MA to correct an SB, associated with several functional and structural anomalies such as Class II division 1 with an increased overjet and overbite as well as a severe curve of Spee in a hypodivergent biotype.

Invisalign Treatment of a Three-Year-Old Child with Bilateral Posterior Scissor Bite and Multisite Upper Airway Obstruction: A Case Report

BACKGROUND

Scissor bites have been reported in relatively few epidemiological studies because of their extremely low prevalence rate (below 1%). The etiology of scissor bites remains obscure, but its impact on growth and function should not be ignored.

METHODS

In this case report, a novel treatment that utilizes Invisalign aligners was performed on a 3-year-old child who presented with a bilateral posterior scissor bite and anterior crossbite, accompanied by multisite obstruction in the upper airway. The aligners functioned as occlusion pads to unlock the scissor bite relationship and combined with cross-traction to narrow the maxillary arch and enlarge the mandibular arch simultaneously.

RESULTS

The duration of orthodontic therapy was 28 weeks. A multidisciplinary consultation (orthodontics department, ENT department, and spinal surgery) was conducted and a stable result was achieved. A healthy occlusal relationship, improved dental esthetics and a better lateral profile were eventually obtained.

CONCLUSIONS

Positive treatment outcomes rely on patients' good compliance in this case. In addition, we hope that clinicians will consider our situation in terms of alternative treatments and interprofessional experience.

Surgical Treatment of Oromandibular Limb Hypogenesis Syndrome Type I A by Distraction Osteogenesis Combined With Orthodontic Rehabilitation

Oromandibular limb hypogenesis syndrome is a rare developmental anomaly and only a few cases are reported with complete surgical and orthodontic rehabilitation. An adult male patient with isolated hypoglossia, micrognathism, hypodontia, (oromandibular limb hypogenesis syndrome type I A) was treated with a combination of distraction osteogenesis and orthodontic intervention. The patient was followed up for the duration of 6 years from his first visit to 4 years after the surgery. The combined procedure resulted in successful and satisfactory treatment of the patient by restoring facial aesthetics, occlusal balance, and functional harmony. However, there was not enough tongue enlargement due to late surgical intervention. The objective of this report is to describe the etiology of hypoglossia, the consequences for oral function, and to share our experience from the oral rehabilitation during the treatment procedure.

Brodie Bite: A Clinical Challenge

Treatment of the posterior crossbite (Brodie bite) case is always challenging for orthodontics. The case requires meticulous treatment planning and is often difficult and time-consuming to treat Brodie bite. This kind of malocclusion develops partially because of lingual tipping of the lower segments, and partially because of a lower jaw too small, relative to the maxilla. A young male 12 years of age came to the dental department with chief complaints of unable to chew food and with lower jaw teeth contained within the upper jaw. Clinical examination revealed class II div I malocclusion, increased overjet and lingually locked upper left lateral incisor with just one occlusal contact at the left first molar region (mandibular teeth contained within the maxillary dentition). Though there are various treatment options available such as extractions, expansion, dental arch compensation, or orthognathic surgery for treating Brodie bite, the best treatment option should be chosen, which requires proper diagnosis. This article discusses one such case that was diagnosed and planned as three-phase treatment with two modifications in mechanotherapy.

Maxillomandibular Transverse Osteodistraction: A Multidisciplinary Case Report with 30-Month Follow-Up

Aim

To describe a multidisciplinary treatment to correct a severe II class malocclusion with reduced both maxillary and mandibular transverse dimensions and dental crowding. Case Report. A 17-year-old young woman presented with an increased overjet complaining chiefly of forwardly placed upper front teeth and unpleasant smile aesthetics. The patient facially exhibited a gently convex profile, severe mentalis strain on lip closure, and dark buccal corridors. The intraoral assessment indicates Class II molar relationship bilaterally, mandibular and maxillary anterior crowding, and narrow shape of upper and lower arches. The cephalometric evaluation of the lateral radiograph of the skull evidences a skeletal Class II with a reduction of lower face height. Based upon the diagnostic records and consultation with the patient, surgically assisted expansion of both arches using bone-borne distractors, comprehensive orthodontic treatment, and combined jaw surgery was planned.

Results

This approach permitted achieving most of the desired objectives in approximately 30 months. The follow-up records 30 months after treatment conclusion showed a stable occlusion. No complications were clinically and radiographically noticeable during the follow-up.

Mandibular bi-directional distraction osteogenesis: A technique to manage both transverse and sagittal mandibular diameters via a lingual tooth-borne acrylic plate and double-hinge bone anchorage

PURPOSE

Mandibular hypoplasia can develop transversely, sagittally, or in both diameters simultaneously. Current techniques achieve either sagittal or transverse expansion with different surgeries. Here, we present a novel method to obtain transverse and sagittal mandibular distraction in one stage.

MATERIALS AND METHODS

The technique consists of a double osteotomy: a dento-alveolar osteotomy comprising four or six anterior teeth and a vertical symphysiotomy underneath. The mandibular basal bone is immediately expanded transversely and fixed to the lower symphysis via a miniplate carrying only one screw on each side that functions as a hinge during active distraction. The plate is connected to the anterior dento-alveolar block with a metal wire ligature. A teeth-anchored lingual distraction system can expand transversely at the alveolar bone level and then sagittally with the anterior dento-alveolar segment wired to the lower plate.

RESULTS

Satisfying and stable results were achieved, confirmed by measurements on serial plaster casts.

CONCLUSION

To the best of our knowledge, this is the first proposal for ortho-surgical correction of both transversal and sagittal mandibular hypoplasia via a bi-directional distraction procedure. A combination of bone-hardware anchorage and dental-anchored distraction systems is suggested. Transmucosal hardware emergence and need for a second surgery to remove bone-borne appliances are avoided.

Trauma-Induced Unilateral Buccal Nonocclusion

Buccal nonocclusion is a difficult situation for orthognathic surgeons. This is the severest form of crossbite with congenital or traumatic origin. Unilateral cases are more difficult and need more attention. Posttrauma-acquired buccal nonocclusion is easier for management than congenital cases that need orthodontic preparation and more complicated orthognathic surgeries. Two cases of trauma-induced unilateral buccal nonocclusion are presented with different etiologies. Preoperative model surgery and posterior segmental surgery are keys to correct trauma-induced buccal nonocclusion.

Correcting severe scissor bite in an adult

Scissor bite often remains unnoticed by patients although it can adversely affect facial symmetry, jaw growth, and mastication. This case report illustrates the efficacy of temporary skeletal anchorage devices (TSADs) and a modified lingual arch in correcting severe scissor bite. A 28-year-old woman presented with severe scissor bite in the mandibular right posterior segment. To treat this condition, TSADs were used for maxillary posterior intrusion and a modified lingual arch for buccally uprighting mandibular posterior teeth. Long-term retention records demonstrate stable treatment results.

Three-dimensional evaluation of mandibular midline distraction: A systematic review

OBJECTIVE

To provide a literature overview on mandibular midline distraction (MMD) using three-dimensional (3D) imaging analysis techniques. Regarding different distractor types, the focus was on changes in position and/or morphology of the mandibular condyle and temporomandibular joint (TMJ), skeletal effects, dental effects, soft tissue effects, and biomechanical and masticatory effects, specifically on the mandible and TMJ.

METHODS

Studies up to March 27 2017 were included, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines, using Embase, Medline OvidSP, Web-of-science, Scopus, Cochrane, and Google Scholar.

RESULTS

Thirty-one full-text papers were assessed for eligibility and 15 met the inclusion criteria: prospective (2), retrospective (2), case-report (1) and computational analysis (10). All included studies were graded low (level 4-5) for quality of evidence, using the Oxford Centre for Evidence-Based Medicine criteria.

CONCLUSION

There is a limited number of studies available, with low levels of evidence and small sample sizes. Bone-borne distraction seems preferable when taking skeletal effects into account. Tooth-borne distraction leads to significant dental tipping. Hybrid distractors combined with parasymphyseal step osteotomy seem to be the most stable under functional masticatory loads. The effects of chewing appeared to be marginal during the latency period. No permanent TMJ symptoms were reported, and little is known about soft tissue effects.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews, PROSPERO CRD42014010010.

Nonsurgical treatment of Brodie bite assisted by 3-dimensional planning and assessment

This case report describes the nonsurgical treatment of an adolescent patient with a severe transverse discrepancy presented as a Brodie bite and retrognathic mandible. Distraction osteogenesis has been often used for similar cases in the literature. However, in this patient, a fixed appliance with 1 maxillary extraction combined with a functional appliance was used to resolve the transverse discrepancy with natural growth. After the orthodontic treatment, the impinging teeth and Brodie bite were corrected with a favorable occlusion and profile. Retention at the 3-year follow-up showed improved occlusal interdigitation and good stability.

New Technique for Mandibular Symphyseal Distraction by a Double-Level Anchorage and Fixation System: Advantages and Results

INTRODUCTION

A surgical technique to widen the mandible is the mandibular midline distraction: the most common indications for mandibular midline distraction are severe mandibular anterior crowding, severe mandibular transverse deficiency, uni- or bilateral crossbite, impacted anterior teeth with inadequate space, and tipped teeth. Commonly used distraction devices can be divided into 2 systems: bone-borne distraction system appliance, dental-borne distraction systems. Each system has peculiar advantages, disadvantages, and different indications. To combine advantages of both systems we developed a new technique adopting an immediate basal bone widening with fixation after osteotomy and a dental borne rigid lingual system for distraction.

AIM

The aim of this work is to show a new technique for symphysis mandibular distraction based on a double-level anchorage and fixation system on clinical patients showing final results and advantages.

METHODS

Two patients affected by dento-alveolar and basal bone maxillary and mandibular transversal collapse even in association with other skeletal malocclusion were selected. Patients were clinically and radiographically studied and analyzed at different times before and after surgery. Dental and basal bone measurements were performed clinically and radiographically.

RESULTS

The results were optimal with perfect dental arches alignment followed by closing of the open bites with multiple-segmented surgery in a second surgical time. No misalignment of the 2 mandibular halves was noticed during the distraction procedure.

DISCUSSION

Dental-bone discrepancies correction is mandatory before orthodontic treatment alignment. Transversal jaw expansion can be achieved safely and stably by distraction of both maxillae for the combination of osteogenesis and histogenesis with augmentation of both bone and soft tissue. Bone-borne distraction will result in more stable results; dental-borne devices will result in more simple and aesthetically rewarding procedures. Hybrid techniques usually show mixed results depending on the characteristics of the device. For this reason we developed a combination of both the aforementioned systems which is not a hybrid system but the combination of an immediate expansion of the symphysis and fixation by 1 miniplate with only 2 screws acting like hinges during distraction, combined with a lingual distraction system at the alveolar bone level.

CONCLUSIONS

Bone-borne distraction systems result in more efficient basal bone mandibular widening with increased stability for dental results. For dental-borne appliance the advantages consist in no second surgery need for their removal, no transmucosal hardware emergence and better aesthetic, especially when lingual devices were used. Our technique combines advantages of both procedures.

[Treatment of a unilateral Brodie's syndrome by surgical contraction of the maxillae]

INTRODUCTION

Brodie's syndrome consists in a transverse occlusal discrepancy in relation with an excessive width of the maxilla, a narrow mandible or a combination of both, leading to lateral scissors bite. This kind of infrequent malocclusion is usually treated by orthodontics alone in children. In adults, additional orthognathic surgery id often required. We present a case of unilateral Brodie's syndrome treated by surgical contraction of the maxillae.

OBSERVATION

A 22-year-old patient presented with a left scissors bite and severe unilateral molar overbite. After failure of an attempt to ingress the left molars by help of a sub-apical corticotomy and anchorage mini-screws, the patient was referred for surgery. The mandible being considered as normal, a segmented Le Fort I osteotomy was planned, combining a contraction (4mm) and an impaction (4mm) of the left maxilla. This allowed for an immediate correction of the skeletal discrepancy and for the achievement of orthodontics in less than 6 months.

DISCUSSION

Le Fort I osteotomy provides a good access to the sagittal suture. Maxillary contraction is an uncommon procedure that enables a quick management of scissors bite and doesn't need any patient cooperation. Treatment time is reduced and the need for intraoral devices is limited.

Treatment of a unilateral complete lingual crossbite in an adult with skeletal anchorage assisted orthodontics

An asymmetry caused by a complete lingual crossbite can compromise aesthetics and impair occlusal function. The following case report describes the correction of a complete lingual crossbite using orthodontic mini implants and mini-plates to achieve absolute anchorage. A comprehensive correction of the crossbite and re-establishment of the buccal occlusion was achieved.

Dentate transport discs can be used to reconstruct large segmental mandibular defects

PURPOSE

This study tested the use of a dentate transport segment for the reconstruction of a large U-shaped defect in the anterior segment of the canine mandible using a novel curved reconstruction plate. The quality and quantity of bone regenerate formed by dentate versus edentulous transport segments were compared.

MATERIALS AND METHODS

In 5 adult foxhound dogs, a defect of 70 to 75 mm was created in the canine mandible by excising the mandible anterior to the right and left fourth premolars. Reconstruction was performed by trifocal distraction osteogenesis using a bone transport reconstruction plate (BTRP-02), with 2 transport units being activated simultaneously, one on either side of the defect, 1 dentate and 1 edentulous. Bilateral distraction proceeded at a rate of 1 mm/day until the segments docked against each other in the midline. After 39 to 44 days of consolidation, the animals were euthanized. The quantity and quality of bone regeneration on the 2 sides were compared using micro-computed tomography.

RESULTS

The defect reconstruction was successful. The amount and quality of bone formed by the transport segments were similar on the 2 sides. There were no major differences in the bone volume fraction and density of the regenerate bone formed by the 2 transport segments. The bone volume fraction and density of the regenerate bone were considerably lower than those of the host bone in the distal segments, likely owing to the short consolidation period.

CONCLUSIONS

Bone transport remains a viable option in reconstructing anterior segmental defects in the mandible. The use of dentate or edentulous transport segments for reconstruction provides options for the surgeon in often highly compromised patients requiring these surgeries.

Severe unilateral scissor bite and bimaxillary protrusion treated by horseshoe Le Fort I osteotomy combined with mid-alveolar osteotomy

This report describes an orthognathic surgical case employing horseshoe Le Fort I osteotomy (HLFO) combined with mid-alveolar osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) for a patient with severe unilateral scissor bite and bimaxillary protrusion. A female patient (aged 26 years, 2 months) presented with a chief complaint of dysmasesis caused by scissor bite on the right side. The clinical examination revealed difficulty in lip closure and a convex profile. Overerupted right maxillary premolars and molars and lingual tipping of the right mandibular premolars and molars were indicated before treatment. After 3 months of presurgical orthodontic treatment, two-jaw surgery involving a combination of HLFO with mid-alveolar osteotomy and BSSRO was performed. A good interdigitation in the right side was established by superior-posterior-medial movement of the dento-alveolar segment of the maxilla. Next, both the maxilla and mandible were moved superiorly and posteriorly to correct the improper lip protrusion, thereby improving the patient's profile. Our results suggest that this new orthognathic surgery technique-achieved by combining HLFO with mid-alveolar osteotomy and BSSRO-is effective for adult patients exhibiting severe unilateral scissor bite and bimaxillary protrusion.

Correction of a dental arch-width asymmetric discrepancy with a slow maxillary contraction appliance

A boy, aged 12 years 3 months, sought treatment for a complete unilateral Brodie bite. His maxillary dental arch was asymmetric, and his dentition was 10 mm wider than normal values for his age. The transverse discrepancy was his chief complaint because it caused a chewing dysfunction. We used a special slow maxillary contraction appliance, which contains a screw, connectors, and retainers, to contract the maxillary transverse asymmetric dental arch. This was followed by preadjusted fixed appliances to level the teeth and adjust the occlusion. A symmetric and functional Class I occlusion was achieved.

Introduction of the "Rotterdam mandibular distractor" and a biomechanical skull analysis of mandibular midline distraction

The Rotterdam mandibular distractor (RMD) is a slim, rigid, boneborne distractor for use in midline distraction of the mandible. We did a biomechanical study to compare the RMD with the Trans Mandibular Distractor-flex (TMD-flex). This included an anatomical biomechanical study that was conducted on 9 dentate human cadaveric heads using both the RMD and the TMD-flex. In the vertical plane less tipping was measured in the RMD group than in the TMD-flex group. Significantly less skeletal tipping was found in the horizontal plane in the RMD group (P=0.021). There was minimal difference in the intercondylar distance between the groups. As the amount of lateral displacement of the condyle was similar in both groups and there was less rotational movement in the RMD group, the TMD-flex would be expected to increase stress on the temporomandibular joint. As a result of the increased parallel widening in the vertical plane, more basal bone is being created and less relapse is expected using the RMD. The study design involves an in vitro anatomical model and conclusions must be drawn with care. At present clinical studies are under way and results will follow.

Mandibular Symphyseal Distraction Osteogenesis Using a Bone-Supported Distractor

Increases in mandibular width by symphyseal distraction osteogenesis have recently been shown to be an acceptable and stable treatment option for transverse deficiencies. This case report presents the application of symphyseal distraction osteogenesis for increasing mandibular width using a bone-supported distractor as part of the orthodontic treatment of a 14-year-old male with a tapered shaped mandible and severe mandibular anterior crowding.