Mandibular Deficiency Research Articles

Simultaneous Costochondral Ramus-Condyle Reconstruction and Mandibular Distraction for Hemifacial Microsomia

Hemifacial microsomia (HFM) is the second most common congenital craniofacial malformation. Structures derived from the first and second pharyngeal arches are aberrant, the hallmark being mandibular diminution. The mandible classically exhibits ramus and condylar underdevelopment,1,2 with actual hypoplasia along all planes of space.3 This results in varying temporomandibular joint (TMJ) derangement, vertical and sagittal mandibular deficiency with chin-point deviation, and facial asymmetry. Extended-spectrum HFM includes the addition of systemic organ involvement, and the severity of facial deformity can predict its likelihood.

Esthetic orthodontic treatment with a double J retractor and temporary anchorage devices

This clinical article reports an esthetic treatment option for managing a Class II malocclusion in an adult. The patient, a woman aged 24 years 2 months, had crowding and a convex profile. She was treated with maxillary first premolar extractions, a double J retractor, and temporary skeletal anchorage devices in the maxillary arch. Posttreatment records after 2 years showed excellent results with good occlusion and long-term stability.

Pivot Technique Combined With Mandibular Backward Distraction Osteogenesis for the Patient With High Risk for Relapse

Severe skeletal relapse is one of the most difficult problems after mandibular advancement, and the management to overcome such problems tends to require more compromised methods and longer treatment period. We described that mandibular backward distraction osteogenesis with maxillomandibular fixation at an appropriate occlusion. Furthermore, to avoid inappropriate distraction vector, the distal plates of the distraction device were fixed with 1 screw to work as a pivot after the manipulation of the condyle to the glenoid fossa at the end of distraction activation. This technique was applied to 3 female patients with mandibular deficiency. The intraoral distractors were set on the lateral surface of the mandibular body; the fixation of the distal plate was fixed with 1 monocortical screw to make the proximal segment including the condyle manipulating at the end of the distraction phase by releasing the maxillomandibular fixation. The distraction rate was 1 mm/d, and the latency period was 7 days. The follow-up period after mandibular backward distraction osteogenesis ranged from 26 to 56 months. No specific complication, such as broken device, severe infection, or bony nonunion, occurred. Postoperative relapse was not observed during the follow-up period. This technique might become 1 choice to apply for mandibular deficiency in a patient with high risk for relapse.

The ability of orthodontists and laypeople to discriminate mandibular stepwise advancements in a Class II retrognathic mandible

ObjectivesThis study analysed the ability of orthodontists and laypeople to discriminate mandibular stepwise advancements. Materials and methodsFour pictures (in duplicate) were taken of a male patient with Class II malocclusion and mandibular deficiency with the mandible positioned in habitual maximum intercuspation (HMI) and with stepwise advancements of 2mm, 4mm and 6mm. These images were examined by orthodontists (n=30) and laypeople (n=30). The Wilcoxon signed-rank test was used to evaluate intra-examiner agreement. Intra-examiner ability to discriminate stepwise mandibular advancements was examined by Friedman's test. A Mann-Whitney's test was carried out to analyse score difference between orthodontists and laypeople. Type I error (alpha) was set as 5% for all statistical tests. ResultsWe observed a satisfactory to excellent level of methodological reliability. While laypeople were able to notice mandibular advancements ≥4mm (p<0.05), orthodontists were able to observe mandibular advancements ≥2mm (p<0.05). The orthodontists were more critical than laypeople with regard to the facial profile evaluation when facial convexity increased (p<0.001), but no significant difference was observed when the sagittal maxillo-mandibular relationship approached normality (p<0.05). ConclusionsConsidering that the mean sagittal mandibular growth due to the use of functional orthopaedic appliances is reported in the literature as 2mm, it seems that laypeople may not able to discriminate this amount of change in facial-profile attractiveness.

The Question Mark Ear in Patients with Mandibular Hypoplasia

Sir:FigureThe question mark ear is characterized by a cleft between the lower part of the helix and the earlobe, sometimes with a prominent upper pole of the pinna, and was first described in 1961.1 The term “question mark ear” was coined in 1970.2 Ear malformations and mandibular hypoplasia can occur together in oculoauriculovertebral spectrum (Online Mendelian Inheritance in Man no. 164210) (including craniofacial microsomia and Goldenhar syndrome), Treacher Collins syndrome (Online Mendelian Inheritance in Man no. 154500), Pierre Robin sequence, and auriculocondylar syndrome (Online Mendelian Inheritance in Man no. 602483). Auricular malformations in four patients with mandibular hypoplasia were reviewed. In case 1, an 11-year-old girl presented with bilateral question mark ears and micrognathia (Fig. 1). Her mother and sister both had a unilateral question mark ear. The patient underwent bilateral mandibular distraction and later ear reconstruction.Fig. 1: Case 1. An 11-year-old girl with bilateral question mark ears and micrognathia.In case 2, a 2-year-old boy presented with a left question mark ear, Pierre Robin sequence, micrognathia, and severe obstructive sleep apnea (Fig. 2). He successfully underwent bilateral mandibular distraction osteogenesis to improve his airway.Fig. 2: Case 2. A 2-year-old boy with Pierre Robin sequence, micrognathia, and a unilateral question mark ear.In case 3, a 3-month-old boy was referred with bilateral question mark ears and severe micrognathia requiring emergency tracheostomy at birth. He had macrostomia with a trifurcated, hypoplastic tongue and gingival hypertrophy. He required bilateral hearing aids. He underwent approximately 20 operations, including mandibular distraction osteogenesis, free fibula mandibular reconstruction, release of jaw ankylosis, temporomandibular joint reconstructions, tongue Z-plasty, release of floor-of-mouth adhesions, iliac bone graft to the anterior mandible, and further bilateral mandibular distraction. In case 4, a 14-year-old boy presented with a left question mark ear and micrognathia. He underwent bilateral vertical L-osteotomies of the mandible with interpositional iliac bone grafts, bilateral coronoidectomies, and alloplastic genioplasty. The question mark ear is rare. It can arise spontaneously or by means of autosomal dominant inheritance, with high intrafamilial variability.3 The cleft associated with the question mark ear can be explained as an arrest of fusion of the fifth (helical) and sixth (lobular) hillocks.4 The reason for any accompanying mandibular or condylar hypoplasia is unknown, but both structures arise from the first pharyngeal arch. The question mark ear is thought to be a diagnostic trait for auriculocondylar syndrome, described in 1978 in a mother and two sons with bilateral external ear malformations and mandibular hypoplasia.5 Condylar hypoplasia, temporomandibular joint abnormalities, microstomia, stenotic ear canals, and hearing loss are associated. Auriculocondylar syndrome has features that overlap with other first and second pharyngeal arch disorders, especially oculoauriculovertebral spectrum. The heart, kidneys, and spine should be evaluated: auriculocondylar syndrome is thought to be similar to Goldenhar syndrome but lacks vertebral anomalies. Expression of auriculocondylar syndrome is variable. Surgery aims to reduce size and prominence of the upper pole of the ear and to correct the cleft.3 The anomaly has been classified as moderate and severe.3 Rib or contralateral conchal cartilage grafts are used to correct cartilage deficiency.4 A V-Y flap from the posterior surface of the ear can be advanced to correct the skin deficiency.4 If a notch remains, a Z-plasty can realign tissue but makes the ear smaller.4 Transposition flaps with cartilage grafts are an alternative. Ear reconstruction should be delayed until after the mandibular deficiency has been corrected, especially if there are associated respiratory problems. Aina V. H. Greig, Ph.D., F.R.C.S.(Plast.) Silvio Podda, M.D. Charles H. Thorne, M.D. Joseph G. McCarthy, M.D. Institute of Reconstructive Plastic Surgery, New York University Langone Medical Center, New York, N.Y. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. PATIENT CONSENT Parents or guardians provided written consent for the use of the patient images.

Treatment of skeletal class II division 1 malocclusion with mandibular deficiency using myofunctional appliances in growing individuals

Class II division 1 malocclusion is the most common malocclusion seen in day-to-day practice. The majority of the patients with class II division 1 malocclusions have the presence of underlying skeletal discrepancy between maxilla and mandible. The treatment of skeletal class II division 1 depends upon the age of the patient, growth potential, severity of malocclusion, and compliance of patient with treatment. Myofunctional appliance can be successfully used to treat growing patients with class II division 1 malocclusion having retrusive mandible. This article presents a discussion on treatment of class II division 1 due to mandibular deficiency with growth modification approach using myofunctional appliances and a series of three case reports of treatment of skeletal class II division 1 malocclusion using myofunctional appliance followed by fixed mechanotherapy.

Upper Airway Sleep Disorders in Children: Orthodontist\'s Role

Significant component of craniofacial development occurs within the first four years of life. A total of 90% of the craniofacial development is complete by the age of 12 years. Therefore, it can be concluded that morphometric features that puts an adult at risk of obstructive sleep apnoea(OSA)or sleep disordered breathing (SDB) were probably present at the age of 12 years. Class II malocclusions, narrow maxilla, mandibular deficiency, retrognathia, long face problems, inferiorly and posteriorly placed hyoid bone are all considered as craniofacial anomalies that predisposes a child to SDB.

Treatment effects of R-appliance and Anterior Inclined Bite Plate in Class II, Division I malocclusion

ObjectivesThe purpose of this study was to compare the effects of a differently designed functional appliance (R-appliance) and the Anterior Inclined Bite Plate (AIBP) in Class II Division I (Cl II Div I) cases. Material and MethodsFifty patients (28 girls, 22 boys) were chosen for the study: 25 patients (13 girls, 12 boys) with mean age of 10.4±0.8 years were treated with R-appliance for 11±2 months, the other 25 patients (15 girls, 10 boys) with mean age of 9±1.2 years were treated with AIBP for 10±2 months. All patients had Cl II Div I malocclusion due to mandibular deficiency. Lateral cephalograms were analyzed at the beginning (T1, T 1) and end of the study (T2, T 2). ResultsPaired T-test showed that SNB had a significant increase in both groups. The same test revealed that IMPA was reduced in R-appliance for 3.1±4.7 (p<0.01), but it was increased for 0.1±5.1 (p<0.9) in AIBP group. T-test showed that the inter-group difference of IMPA was statistically significant (p<0.05). SNA showed an increase in both groups (p<0.9). Ar-B and Ar-Pog showed an increase in both groups and the differences between them were statistically significant. ConclusionsMandibular advancement was achieved in both groups, but R-appliance achieved this result without lingual tipping of lower incisors.

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Distraction of bone grafts to treat severe mandibular deficiency in hemifacial microsomia—a case series

Introduction: The management of the severely deficient mandible in hemifacial micorosomia and other first branchial arch syndromes has involved reconstruction using costochondral grafts in childhood and further reconstruction following skeletal maturation to facilitate definitive orthognathic correction.

Multilocular radiolucency of the mandibular condyle in a 19-year-old woman

A 19-year-old woman presented to the orthodontic department of our institution for evaluation of maxillary excess and mandibular deficiency. On routine cephalometric and panoramic images, an asymptomatic multilocular radiolucent lesion was incidentally noted in the left mandibular condylar area (Fig. 1). The patient was subsequently referred to oral and maxillofacial surgery for a consultation regarding both orthognathic surgery and treatment of the condylar lesion. After the consultation, the patient elected to undergo presurgical orthodontic treatment. Follow-up imaging of the condylar lesion (Fig. 2) was performed 7 months after the first images were obtained. Although the lesion was found to be approximately the same size, the orthognathic surgeon referred the patient to an oral and maxillofacial surgeon who specializes in diseases of the temporomandibular joint (TMJ) for further examination. On examination by the second surgeon, the patient denied any history of trauma. The patient described the left TMJ as “tight,” and mild crepitus was noted. These symptoms were noteworthy because they had not been reported previously. The patient denied any pulsation, paresthesia, or pain. Joint sounds from the bilateral

Restoring Function and Aesthetics in a Class II Division 1 Patient with Amelogenesis Imperfecta: A Clinical Report

Amelogenesis imperfecta (AI) encompasses a complicated group of hereditary conditions that cause developmental alterations in the structure of the enamel in the absence of a systemic disorder. AI primarily affects the quality and/or quantity of dental enamel, and it may affect all or only some of the teeth in the primary and/or permanent dentition. This clinical report describes the oral rehabilitation of a 21-year-old man diagnosed with hypomaturation-type AI. He presented with discolored and mutilated teeth. Cephalometrically, the patient has skeletal class II malocclusion due to mandibular deficiency considered as a result of maxillary constriction. The interdisciplinary approach was followed because of the complex needs of the patient. The aim of treatment was to restore aesthetics, improve malocclusion and masticatory function. Aesthetic and functional expectations were met with metal ceramic restorations. In this report, the interdisciplinary approach for a patient with AI and a malocclusion is described.

External Mandibular Distraction in Unusual Pediatric Syndromes with Micrognathia and Airway Obstruction

Mandibular hypoplasia is a craniofacial malformation that can cause airway obstruction and may affect the eating process. This anomaly is common in many polimalformed Syndromes, including the Pierre Robin Sequence and the Moebius Syndrome. It is also common in cases related to the dysgenesis of the brainstem. In order to avoid tracheostomy, or to allow for early decannulation in severely affected children, external distraction devices were employed in 3 clinical cases to repair mandibular deficiencies. A successful external mandibular distraction induces the removal of the airway obstruction, allowing spontaneous ventilation without devices, an independent eating process with no need of nasogastric or gastrostomy tubes, apart from the linguistic and facial asymmetry improvement.

Bilateral Mandibular Condylysis from Systemic Sclerosis: Case Report of Surgical Correction with Bilateral Total Temporomandibular Joint Replacement

Systemic sclerosis (SSc) is a multisystem connective tissue disease of unknown etiology. The hallmark of SSc is scleroderma, referring to the presence of thickened, hardened skin. Oral and maxillofacial manifestations of the disease are numerous including masklike appearance, trismus, muscular atrophy, thin atrophied lips, secondary microstomia, xerostomia, rigidity of tongue and lips, widening of the periodontal ligament space, trigeminal neuralgia, and resorption of the mandible. A 35-year-old woman with limited cutaneous SSc presented with bilateral mandibular condylysis, severe class II mandibular deficiency, and large anterior open bite and limited range of mandibular opening at 27 mm. Surgical correction consisted of bilateral total temporomandibular joint reconstruction with stock prostheses combined with Le Fort I maxillary impaction and functional advancement genioplasty. This resulted in a functional occlusion with elimination of her open bite and a more esthetic profile. Her occlusion has remained stable at 7 months. The incidence of mandibular resorption in SSc has been found to be 20% to 33%. The mandibular angles are most commonly involved (37.6%), followed by the condyle (20.8%), coronoid process (20.0%), and the posterior border of the ascending ramus (14.4%). Bilateral condylysis is present in 13.7% of the cases. Very few cases of surgical correction of malocclusion induced by SSc-related condylysis have been reported in the literature. To the best of our knowledge, this is the first case report of bilateral condylysis from SSc where surgical replacement of the resorbed condyles was attempted. Bilateral total temporomandibular joint replacement can give these patients a functional occlusion, improved facial balance, and improved quality of life.

A CASE REPORT OF GROWING SKELETAL CLASS II TREATED WITH FORSUS FATIGUE RESISTANCE APPLIANCE

Growing skeletal class II malocclusions with mandibular deficiency have been treated for more than a century with different types of functional appliances. Removable or fixed functional appliances are available to advance the mandible. Fixed functional appliances have the advantage of not requiring patient compliance. They can also be used concurrently with brackets. This case report documents the successful treatment of mild skeletal class II in late stages of puberty by using Forsus fatigue resistance appliance. The Forsus appliance is a three-piece, semi-rigid telescoping system incorporating a super-elastic nickel-titanium coil spring that can effectively brings the mandible forward in a relatively shorter treatment time. It is compatible with complete fixed orthodontic appliances and can be incorporated into preexisting appliances.

Timely relocation of mini-implants for uninterrupted full-arch distalization

This report describes a novel concept of relocating orthodontic mini-implants during dental distalization to provide unrestricted distal movement of the full maxillary dentition. The patient was an 18-year old Korean woman with a full-step Class II Division 1 malocclusion and mandibular deficiency. Mini-implants were initially placed bilaterally between the maxillary second premolar and the first molar. Sliding jigs were used to distalize the maxillary first and second molars. After the maxillary molars were distalized to a Class I molar relationship, the mini-implants were removed and immediately relocated distally to provide space for retraction of the anterior teeth. The occlusion was completed with Class I molar and canine relationships with optimal overjet and overbite. The 2-year posttreatment records showed a stable treatment with retention.

Berlin standard activator in the treatment of growing patients with mandibular deficiency: Case report

Activator is a removable functional appliance used for correcting the skeletal Class II malocclusion in children with the mandibular deficiency. Berlin standard activator modified from Andresen activator has following characters; do not cover the palatal surface for tongue space, relief on lingual surface of mandibular incisors and resin capping 1/3-1/2 of crown height on mandibular incisors for preventing labioversion of mandibular incisors, L-hook between maxillary lateral incisor and canine for anterior high pull headgear, relief on mandibular posterior bite block for differential eruption of posterior teeth. Two cases presented here had a mandibular deficiency and slight maxillary protrusion. First case (an 11-year-old girl) treated with Berlin standard activator and anterior high pull headgear for 13 months followed by fixed orthodontic appliance for another 29 months. Second case (a 12-year-old boy) treated with Berlin standard activator for 6 months followed by fixed appliance for another 24 months. Treatment results showed a significant improvement in sagittal skeletal and occlusal relationship without premolar extraction. Mandibular condyles were concentric in TMJ [ossa, and masticatory muscle activities were normalized after treatment. In the retention period facial harmony and occlusal stability was maintained.

La distraction symphysaire : protocole simplifié

Severe mandibular incisor crowding with bone insufficiency is usually treated by dental extractions and orthodontic management. Symphyseal distraction was proposed to avoid tooth extraction. This technique is still considered as invasive, complex and unsafe. We evaluated symphyseal distraction to clarify its indications, and to suggest a simplified surgical protocol.Six patients were treated by symphyseal distraction: three with a bone-anchored device and three with a dental anchored one. Pre and postoperative inter-canine measurements and occlusal stability were analyzed.Postoperative inter-canine measurements increased from 3.4 to 6.8mm (mean 5.2mm). All patients were in Angle class I occlusion without complications. Dental anchored device simplified the surgical procedure.Symphyseal distraction with dental anchored device is a simple, efficient and reliable to treat severe transverse mandibular deficiency. The orthodontist can manage the procedure by himself and controls the whole expansion process according to specific requirements.

Treatment effects of the R-appliance and twin block in Class II division 1 malocclusion

The purpose of this study was to compare the effects of a differently designed functional appliance (the R-appliance) with a twin-block (TB)-treated group. Thirty patients (18 girls and 12 boys) with a mean age of 10.5±0.7 years were treated with the R-appliance for 16.2±0.3 months and 25 (11 boys and 14 girls) with a mean age of 11.2±1.3 years with a TB for 16.1±1.4 months (control). All had a Class II division 1 malocclusion due to mandibular deficiency. Lateral cephalograms obtained at the beginning (T1) and end (T2) of the study were analysed. Paired t-tests showed that SNB significantly increased in both groups. The incisor mandibular plane angle (IMPA) was reduced in the R-appliance group by 1.9±4.9 degrees (P<0.04) but increased by 0.5±5.1 degrees (P<0.6) in the TB group. SNA in the R-appliance group showed an increase of 0.2±1.8 degrees (P<0.5), while it was decreased by 0.2±1.3 degrees (P<0.3) in the TB group. Both treatment modalities were successful in moving the mandible forward. However, with the R-appliance, this was achieved without retroclination of the lower incisors.

Het streven naar faciale harmonie

In the treatment of patients with an oro-facial anomaly the functioning of the masticatory system and aesthetic aspects play a role. Recently, the software programme 'Facial Harmony', which analyzes the soft tissue contour of the face, appeared. Using this programme, a research project was carried out to find out if the result of the surgical treatment of 40 patients with an oro-facial anomaly satisfied the,facial harmony requirements. Only 65% of the treatment results met the requirements. It was especially the patients who had been treated for mandibular deficiency with mandibular and horizontal lines meeting at a wide angle who showed no facial harmony. Only 30% of those patients demonstrated facial harmony postoperatively. If the surgical treatment had been completed by a genioplasty, this percentage would very probably have risen to 85.