Mandibular Deficiency Research Articles

Management of temporomandibular joint ankylosis in children with arthroplasty and distraction osteogenesis in the same surgical time

Temporomandibular joint (TMJ) ankylosis in children is a challenging problem for the maxillofacial surgeon since the surgical technique is difficult and the recurrence rate is high. It is characterized by a hipomobility, breathing, eating problems,and facial asymmetry. There is a vertical and sagittal mandibular deficiency. Numerous treatment approaches have been proposed in the literature. The surgical excision of the ankylotic mass is mandatory; gap arthroplasty and interpositional flaps have been discussed.

Effects of chin advancement surgery in hyoid bone and tongue positions and in the dimension of the oropharynx

Advancement genioplasty has been increasingly indicated for the correction of anterior mandibular deficiency as it balances the patient's profile and generates functional changes. Thus, the aim of this study was to assess the effects of advancement genioplasty in the oropharyngeal size and in the position of the hyoid bone and tongue. The sample comprised 22 lateral cephalometric radiographs of 11 individuals who had undergone advancement genioplasty alone. Eleven of these radiographs depicted the immediate preoperative period (T0) and the other 11 the postoperative period after at least four months (T1). The radiographs were scanned and exported to the Radiocef Studio 2.0® software (Radio Memory Ltda., Belo Horizonte, MG, Brazil). The landmarks were then identified and automatically measured by the program. The results showed statistically significant differences between the horizontal position of the hyoid bone and tongue and in the oropharyngeal size. The hyoid bone and tongue were repositioned anteriorly after surgery (p = 0.01), thereby increasing the dimension of the oropharyngeal airspace (p = 0.01). The oropharyngeal dimension increased as the tongue base and hyoid bone were repositioned more anteriorly.

Combined Unilateral Mandibular Body and Ramus Lengthening by Intraoral Distraction Osteogenesis

Severe unilateral mandibular deficiency remains a challenge in facial reconstruction. The problem is 3-D and needs to be approached by increasing the mandible morphology by ramus and body lengthening and asymmetric genioplasty, adjunctive functional or cosmetic procedures are performed in a second stage; the surgical approach is based on the unilateral mandibular diagnosis: temporo mandibular anquilosis, craniofacial microsomia type I, II or patients with CFM type III.

Model to assess duration of distraction compared with degree of incisal crowding in symphyseal distraction osteogenesis

Our aim was to evaluate symphyseal distraction in relation to duration of expansion, and to propose an optimised procedure. Eighteen patients (mean (SD) age 19 (7) years) with transverse mandibular deficiency were treated by symphyseal distraction osteogenesis. The mean (SD) anterior dental crowding measured was 6.8 (4.2)mm. We retrospectively compared the width of expansion between the canines (ICE) and expansion between the first molars (IFME) after symphyseal distraction according to the distraction time. The median (range) duration of expansion was 13.6 (7–21) days. The median (range) ICE distraction width was 5.5 (3.4–8)mm and IFME width 3.3 (1–7.9)mm (p<0.001). There was a significant correlation between expansion width and distraction time (p<0.001). The transverse anterior and posterior expansion widths differed significantly until 14 days after expansion. The expansion ratio (ICE:IFME) decreased as expansion time increased. The results suggest that the duration of activated expansion can be predicted from the degree of incisal crowding using the formula: distraction time (days)=0.84+3.4×[IC (mm)]−0.2×[IC (mm)]2.

Long-term results of bilateral mandibular distraction osteogenesis using an intraoral tooth-borne device in adult Class II patients

The aim of this prospective clinical study was to evaluate the short-term and long-term skeletal and dental changes after mandibular osteodistraction with tooth-borne appliances in adult orthodontic patients. The sample consisted of 10 non-growing Caucasian patients with a Class II skeletal relationship due to mandibular deficiency, together with Class II dental malocclusion. All patients underwent mandibular distraction osteogenesis (MDO) using the ROD1 tooth-borne device. Lateral cephalograms were evaluated at four time intervals: pretreatment (T1), after mandibular distraction (T2), after orthodontic fixed appliance therapy (T3), and at long-term observation 8-year post-distraction (T4). Statistical analyses compared the skeletal and dental changes in intervals T1–T2, T2–T3, T3–T4, T1–T4, and T2–T4. MDO with the ROD1 tooth-borne device produced significant long-term (T1–T4) increases in the SNB angle (2.3°), total mandibular length (5.9mm), and corpus length (4.5mm). Potential adverse sequelae included significant increases in mandibular plane angle (4.3°), lower anterior dental height (2.8mm), and lower posterior dental height (2.5mm). Significant increases in lower incisor proclination occurred during distraction (7.5°). Distraction osteogenesis with tooth-borne appliances offers a minimally invasive surgical method with stable results for correcting mandibular deficiency in non-growing patients.

Class II surgical-orthodontic treatment of a patient with severe coronary disease: 5 years of follow-up

This case study describes the retreatment and long-term follow-up care of a patient with a medical history of 2 heart surgeries and a Class II malocclusion that included a severe anteroposterior skeletal discrepancy characterized by mandibular deficiency. The patient's initial orthodontic camouflage treatment was poorly performed and failed to correct the maxillofacial disorders. In this article, we report the successful retreatment with a surgical-orthodontic protocol and include the 5-year follow-up records showing stable results. Guidelines for the stratification of cardiac risk are included.

Changes in the pattern of patients receiving surgical-orthodontic treatment

The characteristics of patients who seek and accept orthognathic surgery appear to be changing over time but have not been well documented in the 21st century. Records for patients who had orthognathic surgery at the University of North Carolina from 1996 to 2000 and from 2006 to 2010 were reviewed to collect data for changes in the prevalence of patients with mandibular deficiency (Class II), maxillary deficiency or mandibular prognathism (Class III), long face, and asymmetry problems. The changes were compared with those in previous time periods and at other locations. Between 1996 and 2000 and between 2006 and 2010, the percentage of Class III patients increased from 35% to 54%, and the percentage of Class II patients decreased from 59% to 41%, while the percentages for long face and asymmetry showed little change. The decrease in Class II patients was accentuation of a long-term trend; the increase in Class III patients occurred only after the turn of the century. A similar but less-marked change has been noted at some but not all other locations in the United States. It appears to be related primarily to an increase in the numbers of African Americans, Native Americans, Hispanics, and Asians who now are seeking surgical treatment, but it also has been affected by changes in where orthognathic surgery is performed, decisions by third-party payers (insurance and Medicaid) about coverage for treatment, and the availability of nonsurgical orthodontic treatment options for Class II patients.

Comparative Study of the Bionator and Multi. P Appliances in the Treatment of Class II Malocclusion: a Cephalometric Study

Background: Functional appliances such as Bionator have been used to treat Class II malocclusion. The purpose of this study was to compare the skeletal, dental and soft tissue effects of Bionator appliances with Multi-P (a newly developed appliance) in the treatment of Class II malocclusion.&#x0D; Subjects and methods: 45 class II children were chosen and randomly assigned to either the Bionator or Multi-P treatment group. After excluding 13 patients from the study, 21 patients in Bionator and 11 patients in Multi-P group have participated in the study. Lateral cephalograms were analyzed at the beginning (To) and at the end of treatment (T1) to evaluate the changes in both groups. The paired t.test and Leven’s test were enrolled for statistical analysis.&#x0D; Results: Reduction of ANB angle was detected in both treatment groups. The Bionator group underwent insignificant greater mandibular advancement as measured by the SNB angle. (p= 0.737) The mandibular plane angle increased insignificantly in both groups. (p&gt; 0.05) The inclination of upper incisors decreased significantly in Multi-P group. (p= 0.042)&#x0D; Conclusion: Both appliances are effective therapeutic means for class II treatment associated with mandibular deficiency and may lead to normalization of the dentoskeletal parameters at the end of the treatment.

Complications of Bilateral Sagittal Split Osteotomy in Patients with Mandibular Prognathism

Introduction: Bilateral sagittal split osteotomy (BSSO) of mandible is vastly used in treatment of mandibular deficiencies and discrepancies. Since this method could affect esthetic as well as function, evaluating these effects from various aspects is crucial. This study assessed the effects of this technique on the function of masseter muscle, jaw movements, and sensory changes along with failures in screws used for fixation. Methods: 48 patients with mandibular prognathism participated. Electromyography (EMG) of the masseter muscle; limits of jaw movements including maximum opening (MIO), protrusive (PM), lateral movements (LLE and LRE); presences of sensory changes and two point discrimination test; and number of removed screws were recorded at the baseline, 3 months, and 6 months after surgery. Results: EMG activity of masseter decreased significantly 3 months after the surgery. However, after 6 months the masseter activity revealed no statistically significant difference with baseline activity. There was a significant decrease in MIO and PM after 3 months. The 6 month measurement of MIO and PM was also lower than baseline. However, no difference was observed between LRE and LLE in both follow up sessions. Among 46 patients, 27 patients developed lip paresthesia 3 months after surgery. After 6 month, lip paresthesia remained in 11 patients. Among 276 screws used for fixation 3 screws removed due to exposure to oral cavity and 2 due to patient discomfort. Conclusion: As BSSO in patients with mandibular prognathism revealed temporary functional and sensory changes, it is a safe and appropriate method in orthognathic surgery.

Prevalence and treatment of dentofacial deformities on a multiethnic population: a retrospective study

The purpose of the present study was to retrospectively analyze patients with dentofacial deformities attending a reference center in a Brazilian educational institution who sought orthosurgical treatment. The medical records of 251 patients who sought treatment from 2003 to 2011 at Piracicaba Dental School, State University of Campinas (Unicamp) were analyzed. The exclusion criteria were as follows: patients presenting syndromes and labiopalatal clefts; in addition, incomplete records were excluded from the study. The prevalence of dentofacial deformities was greater in women (60.93 %), as well as leukoderma patients (69.22 %). The main motivation for treatment was functional (52 %), followed by esthetics (27 %). As for skeletal pattern, class III was the most incident (55 %), followed by class II (29.5 %) and class I (15.5 %). Regarding the type of deformity, class I patients had predominantly maxillary atresia (53 %). In the case of class II patients, the main deformity was anteroposterior mandibular deficiency (89 %), and in class III, anteroposterior maxillary deficiency (51 %). The results of the present study suggest that the profile of patients bearing dentofacial deformities in this population is composed of mostly young women motivated by functional issues, and class III skeletal deformity is the most common.

New Therapeutics in Promoting and Modulating Mandibular Growth in Cases with Mandibular Hypoplasia

Children with mandibular growth deficiency may develop airway obstruction. The standard treatment of severe airway obstruction involves invasive procedures such as tracheostomy. Mandibular distraction osteogenesis has been proposed in neonates with mandibular deficiency as a treatment option to avoid tracheostomy procedure later in life. Both tracheostomy and distraction osteogenesis procedures suffer from substantial shortcomings including scarring, unpredictability, and surgical complications. Forward jaw positioning appliances have been also used to enhance mandible growth. However, the effectiveness of these appliances is limited and lacks predictability. Current and future approaches to enhance mandibular growth, both experimental and clinical trials, and their effectiveness are presented and discussed.

Surgical Orthodontic treatment of Skeletal Class II malocclusion

Traditional technique for correcting Class II in a growing patient is by growth modulation. In adults Class II discrepancy are treated either by orthodontic or comaflauge or by surgical correction. Class II discrepancies with mandibular deficiency are treated surgically by mandibular advancement surgery. Mandibular advancement by BSSO is found to be a stable procedure. An 18year old patient reported to the department with complains of forwardly placed upper front teeth. On examination patient had a retrognathic mandible with Class II relation. Intra orally patient had a Class II molar and incisor relation with increased overjet and overbite. The treatment plan of combination of orthodontics and surgery was employed to correct the discrepancy and obtain an aesthetic, harmonious facial profile. The mandibular advancement surgery was done which accomplished the objectives of the treatment.

Management of severe class II division II malocclusion using simplified MPA - A case report

A fully established Class II Div. II malocclusion case with severe mandibular deficiency treated with simplified mandibular protraction appliance (MPA) along with Begg's looped archwire is presented. This type of case with antero-posterior and vertical skeletal dysplasia demands correction of the underlying skeletal malocclusions in growing patients. The task becomes very daunting especially in patients with skeletal deep bite with retroclined upper incisors. One such case treated to produce optimal skeletal and dentoalveolar relationship with the help of a fixed functional device is illustrated in this case report.

Hereditary Gingival Fibromatosis: A Review and a Report of a Rare Case

Hereditary gingival fibromatosis (HGF) is a rare condition which manifests itself by an enlarged gingival tissue covering teeth to various extents. The condition may occur isolated or as part of a syndrome. This paper presents a case of 9-year-old female patient suffering from HGF with chief complaint of mouth protrusion. Cephalometric findings showed severe mandibular deficiency and vertical maxillary excess. Patient exhibited perioral muscle contraction on mouth closing. After discussing the treatment possibilities with the patient and her parents, the decision was made to wait until growth potential decreases (following the adolescent growth spurt) and to correct the problem with orthognathic surgery.

Early Intervention in Skeletal Class II and dental Class II division I malocclusion

A Class II malocclusion may occur as a result of mandibular deficiency, maxillary excess, or a combination of both. However, the most common finding is mandibular skeletal retrusion. The use of functional jaw orthopedics, at the right time during growth, can ultimately result in malocclusion patients achieving an excellent functional occlusion, a broad beautiful smile, a full face with a beautiful jaw line, and profile. Functional jaw orthopedic (FJO) appliances are designed to encourage adaptive skeletal growth by maintaining the mandible in a corrected forward position. The activator developed by Andresen is one of the most widely used for this purpose. A 12-year-old boy with skeletal Class II malocclusion and dental Class II div I malocclusion, a low mandibular plane angle was treated with growth modulation using an activator followed by molar distalization using fixed orthodontics for detailing of the occlusion. The major effects of the activator treatment in this case have been due to increase in condylar growth and also an increase in mandibular base length. Further, non-extraction fixed orthodontic treatment for proper interdigitation of the dentition also helped to maintain the stability of the satisfactory results achieved.

Correction of mandibular deficiency by inverted-L osteotomy of ramus and iliac crest bone grafting

This study was to describe the use of inverted-L osteotomy of ramus and iliac bone graft for the management of mandibular deficiency in adult patients. From 2008 to 2010, 11 patients (aged 19 to 29 years) with mandibular deficiency underwent intraoral or extraoral inverted-L osteotomy of ramus and iliac crest bone grafting. Data were collected from the patients' records, photographs and radiographs. The height and width of the ramus were successfully expanded by inverted-L osteotomy and iliac crest bone grafting with minimal complications in all patients, resulting in significant improvement in occlusion and facial appearance. Our early results showed that the inverted-L osteotomy of ramus and iliac crest bone grafting is safe and effective, and should be considered as a good alternative for the patients with mandibular deficiency.

Evaluation of Upper Airway Dimensional Changes and Hyoid Position Following Mandibular Advancement in Patients With Skeletal Class II Malocclusion

Class II skeletal malocclusion due to mandibular deficiency is considered a risk factor for sleep disorders due to oropharyngeal airway deficiencies. In view of the above, a prospective interventional study was undertaken to evaluate upper airway dimensional changes and position of hyoid bone by comparing pretreatment and posttreatment lateral cephalograms. The objective also included the establishment of the ratio of mandibular advancement to increase in airway dimensions. Pretreatment and posttreatment lateral cephalograms of 20 adults (13 females and 7 males) with skeletal class II malocclusion treated by combined orthodontics and bilateral sagittal split ramus osteotomy was evaluated for changes in posterior airway space (PAS), superior airway space (SAS), minimum airway space (MAS), hyoid bone position (MP-H), effective mandibular length (Co-Gn), mandibular corpus length (Go-Pg), and pogonion position (N perpendicular-Pg). The cephalograms were manually traced by a single operator and the data analyzed using MINITAB 13.2 version software. There was a statistically highly significant (P = 0.0001) increase in PAS, SAS, MP-H, Co-Gn, and Go-Pg. The mean ratio of mandibular advancement to increase PAS, SAS, and MAS was 1:0.35, 1:0.34, and 1:0.24, respectively. Hyoid bone moved superiorly and in an anterior direction by 2.1 ± 2.8 mm and was found to be statistically highly significant (P = 0.0001). The study showed an overall increase in airway dimension and improvement in hyoid position. Thus, the procedure may be considered beneficial in reducing upper airway collapsibility and preventing sleep disorders due to oropharyngeal airway deficiencies in skeletal class II malocclusion.

Facial shape and asymmetry in 5-year-old children with repaired unilateral cleft lip and/or palate: an exploratory study using laser scanning

To investigate the feasibility of facial laser scanning in pre-school children and to demonstrate landmark-independent three-dimensional (3D) analyses for assessment of facial deformity in 5-year-old children with repaired non-syndromic unilateral cleft lip and/or cleft palate (UCL/P). Faces of twelve 5-year-old children with UCL/P (recruited from university hospitals in Cardiff and Swansea, UK) and 35 age-matched healthy children (recruited from a primary school in Cardiff) were laser scanned. Cleft deformity was assessed by comparing individual faces against the age and gender-matched average face of healthy children. Facial asymmetry was quantified by comparing original faces with their mirror images. All facial scans had good quality. In a group of six children with isolated cleft palate coincidence with the average norm ranged from 18.8 to 26.4 per cent. There was no statistically significant difference in facial asymmetry when compared with healthy children (P > 0.05). In a group of six children with UCL with or without cleft palate coincidence with the average norm ranged from 14.8 to 29.8 per cent. Forehead, midface and mandibular deficiencies were a consistent finding, ranging from 4 to 10mm. The amount of 3D facial asymmetry was higher in this group (P < 0.05). Facial laser scanning can be a suitable method for 3D assessment of facial morphology in pre-school children, provided children are well prepared. Landmark-independent methods of 3D analyses can contribute to understanding and quantification of facial soft tissue cleft deformity and be useful in clinical practice.

Obstructive sleep apnea

Obstructive sleep apnea (OSA) is a disease characterized by the occurrence of at least five 10-second pauses in breathing (apnea) or abnormally low breathing events (hypopnea) accompanied with a decrease in blood oxygen saturation by 2-4% per hour of sleep, despite continued, or even intensified, movements of respiratory muscles. OSA is diagnosed in 4% of men and 2% of women who develop the disease later, usually after the menopause. The severity of the disease is assessed with Apnea Hypopnea Index (AHI) indicating the average number of apneas and hypopneas per hour of sleep. OBS is a multicausal disease. The reported risk factors include: obesity, anatomical and post-inflammatory abnormalities in the structure of upper respiratory tract, inappropriate sleep hygiene, maxillary and mandibular deficiencies. The disease may lead to numerous life-threatening complications. Maintaining a correct body mass, good sleep hygiene, rational use of hypnotic drugs and appropriate surgical-orthodontic treatment of patients with malocclusions and anatomic craniofacial anomalies are the basic principles of preventing OBS in patients prone to this disease.

Condylar Resorption After Orthognathic Surgery: A Systematic Review.

The aim of this research was to evaluate the risk factors related to condylar resorption (CR) after orthognathic surgery. Was realized a systematic review with a search of the literature performed in the electronic databases PubMed, MedLine, Ovid, Cochrane Library for current evidence in the world literature as conducted, and relevant articles were selected in according to inclusion and exclusion criteria and the findings were compared. Eight papers, (follow-up 12 months to 69 months) were including. A sample of 2567 patient with mandible or bi maxillary surgery with an age range from 14 to 46 year old was observed. In 137 patients (5.3%) CR was observed, with a 97.6% (122) female. CR was related to 118 cases with mandibular deficiencies with high mandibular plane (advancement surgery). CR were present principally in bi maxillary surgery with a 103 cases (75.2%) and only two papers show any analysis to the relation with TMJ dysfunction. Current evidence in CR is poor but supports those female patients with mandibular deficiency and high mandibular plane angle submitted to bi maxillary surgery with change in occlusal plane (counterclockwise) are associated with condylar resorption after orthognathic surgery.