Mandibular growth in survivors of pediatric parotid gland carcinoma treated with interstitial brachytherapy.

BACKGROUND: The aim of the study was to present long-term results of mandibular growth in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. PROCEDURE: Twenty-five survivors of pediatric parotid gland carcinoma treated with iodine-125 seed interstitial brachytherapy were included for quantitative analysis, including three dimensional (3D) cephalometry and measurement of mandibular volume. RESULTS: 3D cephalometry showed that the median fore-and-aft increments of the lengths of the condyle, the ramus, and the body of the mandible were 1.23, 0.19, and 1.66 mm for the affected side, respectively, and were 1.37, 1.95, and 3.42 mm for the unaffected side, respectively. The difference in increments of the ramus was statistically significant between the affected side and the unaffected side (P = 0.003; P < 0.05). Moreover, mandibular volume measurements showed that the median fore-and-aft increments of the volumes of the condyle, the ramus, and the body of the mandible were 290.62, 220.14, and 1706.40 mm3 for the affected side, respectively, and were 269.15, 370.40, and 1469.86 mm3 for the unaffected side, respectively. The difference in increments was statistically significant between the affected side and the unaffected side for the ramus (P = 0.005; P < 0.05) and the body (P = 0.043; P < .05). CONCLUSION: Mandibular growth was affected by interstitial brachytherapy, especially for the ramus, in pediatric parotid gland carcinoma survivors treated with interstitial brachytherapy. Nevertheless, the impact was mild in these survivors.

Relationship between the cranial base and the mandible in artificially deformed skulls.

OBJECTIVES: There is controversy regarding the relationship between mandibular position and alterations of the cranial base that provoke a more anterior location of the glenoid fossa. Artificially deformed skulls display marked alterations of the cranial base. This study evaluates mandibular changes as function of the morphology of the cranial base in these skulls. MATERIAL AND METHODS: A geometric morphometric study was performed on lateral cephalometric X-rays of three groups of skulls: 32 with anteroposterior deformity, 17 with circumferential deformity and 39 with no apparent deformity. RESULTS: In artificially deformed skulls, the cranial base was deformed causing the mandibular condyle to be in a more anterior position. There was a complete remodelling of the mandible involving narrowing and elongation of the mandibular ramus, rotation of the corpus of the mandible and increased vertical height of the symphysis. Forward displacement did not occur. Integration between mandible and cranial base is not altered by deformation of the skull. CONCLUSIONS: Deformity of the cranial vault exerts an influence on the mandible, supporting the theory of modular units in complete integration. This also supports the theory that mandibular prognathism is a multifactorial result and not a direct effect of displacement of the cranial base.

La artritis reumatoidea juvenil y su influencia en la alteración de desarrollo de la mandíbula / Juvenile rheumatoid arthritis and its influence on the alteration of jaw development

La artritis reumatoidea juvenil (ARJ) es una enfermedad inflamatoria autoinmune que se presenta en niños menores de 16 años. Es de curso crónico, etiología desconocida, y afecta sobre todo las articulaciones, como la temporomandibular (ATM). El daño de la ATM puede ocasionar: alteraciones en el crecimiento facial (micrognatia), maloclusión clase II, mordida abierta anterior, desviaciones laterales, erosiones óseas, destrucción del cón-dilo, oclusión disfuncional y alteración de la estética facial, entre otras consecuencias. La posición oclusal neurofisiológica lograda por medio de elementos electrónicos, como el Transcutaneus Electrical Neural Stimulation (TENS), y mantenida por el Dispositivo Intaroral (DIO) podría posibilitar la remodelación de la cabeza del cóndilo, en pacientes en crecimiento, en los que la enfermedad se halla controlada, regulando así también la sintomatología dolorosa...

Preservation and promotion of bone formation in the mandible as a response to a novel calcium-phosphate based biomaterial in mineral deficiency induced low bone mass male versus female rats.

Calcium and other trace mineral supplements have previously demonstrated to safely improve bone quality. We hypothesize that our novel calcium-phosphate based biomaterial (SBM) preserves and promotes mandibular bone formation in male and female rats on mineral deficient diet (MD). Sixty Sprague-Dawley rats were randomly assigned to receive one of three diets (n = 10): basic diet (BD), MD or mineral deficient diet with 2% SBM. Rats were sacrificed after 6 months. Micro-computed tomography (µCT) was used to evaluate bone volume and 3D-microarchitecture while microradiography (Faxitron) was used to measure bone mineral density from different sections of the mandible. Results showed that bone quality varied with region, gender and diet. MD reduced bone mineral density (BMD) and volume and increased porosity. SBM preserved BMD and bone mineral content (BMC) in the alveolar bone and condyle in both genders. In the alveolar crest and mandibular body, while preserving more bone in males, SBM also significantly supplemented female bone. Results indicate that mineral deficiency leads to low bone mass in skeletally immature rats, comparatively more in males. Furthermore, SBM administered as a dietary supplement was effective in preventing mandibular bone loss in all subjects. This study suggests that the SBM preparation has potential use in minimizing low peak bone mass induced by mineral deficiency and related bone loss irrespective of gender. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1622-1632, 2016.

Correction of a Overjet and Overbite In Class II Division 1 Malocclusion Using Twin Block Appliance Therapy: A Case Report.

Class II division 1 malocclusion is the most common malocclusion. It shows specific clinical characteristics such as large overiet and deep overbite resulting in a soft tissue profile imbalance. Majority of the patients with class II division 1 malocclusions have an underlying skeletal discrepancy between the maxilla and mandible. The treatment of skeletal class II division 1 malocclusion is done taking into consideration the age, growth potential, severity of malocclusion, and compliance of patient with treatment. Myofunctional appliances can be successfully used to treat growing patients with class II division 1 malocclusion. This article presents a discussion on successful treatment of class II division 1 malocclusion with growth modification approach using twin block appliances.

Impact of local steroid or statin treatment of experimental temporomandibular joint arthritis on bone growth in young rats.

INTRODUCTION: Juvenile idiopathic arthritis in temporomandibular joints (TMJs) is often treated with intra-articular steroid injections, which can inhibit condylar growth. The purpose of this study was to compare simvastatin (a cholesterol-lowering drug that reduces TMJ inflammation) with the steroid triamcinolone hexacetonide in experimental TMJ arthritis. METHODS: Joint inflammation was induced by injecting complete Freund's adjuvant (CFA) into the TMJs of 40 growing Sprague Dawley rats; 4 other rats were left untreated. In the same intra-articular injection, one of the following was applied: (1) 0.5 mg of simvastatin in ethanol carrier, (2) ethanol carrier alone, (3) 0.15 mg of triamcinolone hexacetonide, (4) 0.5 mg of simvastatin and 0.15 mg of triamcinolone hexacetonide, or (5) nothing additional to the CFA. The animals were killed 28 days later, and their mandibles were evaluated morphometrically and with microcomputed tomography. RESULTS: The analysis showed that the TMJs subjected to CFA alone had decreased ramus height compared with those with no treatment (P <0.05). Groups that had injections containing the steroid overall had decreases in weight, ramus height, and bone surface density when compared with the CFA-alone group (P <0.0001). Groups that had injections containing simvastatin, however, had overall increases in weight (P <0.0001), ramus height (P <0.0001), condylar width (P <0.05), condylar bone surface density (P <0.05), and bone volume (P <0.0001) compared with the groups receiving the steroid injections, and they were not different from the healthy (no treatment) group. CONCLUSIONS: Treatment of experimentally induced arthritis in TMJs with intra-articular simvastatin preserved normal condylar bone growth.

The effect of light-emitting diode and laser on mandibular growth in rats.

OBJECTIVE: To evaluate the effect of a light-emitting diode (LED) and/or low-level laser (LLL) with or without the use of anterior bite jumping appliances (also known as functional appliances [FAs]) on mandibular growth in rats. MATERIALS AND METHODS: Thirty-six 8-week-old male Sprague-Dawley rats weighing 200 g were obtained from Charles River Canada (St. Constant, QC, Canada) and were divided into six groups of six animals each. Groups were as follows: group 1: LLL; group 2: LLL + FA; group 3: LED; group 4: LED + FA; group 5: FA; and group 6: control (no treatment). Mandibular growth was evaluated by histomorphometric and micro computed tomographic (microCT) analyses. RESULTS: The LED and LED + FA groups showed an increase in all condylar tissue parameters compared with other groups. CONCLUSION: The LED-treated groups showed more mandibular growth stimulation compared with the laser groups.

Effectiveness of a fixed anterior bite plane in Class II deep-bite patients.

Orthodontic treatment of patients with distoclusion combined with dental deep bite and linguo version of the front upper teeth is one of the most difficult forms of malocclusion to treat to a functional and morphological optimum. Our objective was to analyze the efficacy of a fixed anterior bite plane appliance to disclude the teeth and correct this type of malocclusion. At the Department of Orthodontics MSUMD (Moscow State University of Medicine and Dentistry), we proposed the use of a fixed anterior bite plane for the effective treatment of patients with distoclusion combined to a dental deep bite. This appliance was used in 35 patients aged 11 to 15 years (13.2 +/- 1.2) with distoclusion combined with deep bite in a therapeutical approach that also involved an osteopathic correction. The appliance permitted the correction of the distoclusion by discluding the posterior teeth, allowing eruption of the molars and premolars which improved the occlusal plane line (Curve of Spee) and changed the inclination of the upper incisors which liberated the mandible from its retruded position. We also noted an effect on the postural status of the patient.

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.

A multidisciplinary approach to the treatment of oral manifestations associated with Beckwith-Wiedemann syndrome: a long-term case report.

BACKGROUND: Beckwith-Wiedemann syndrome (BWS) is a congenital disorder that involves a somatic overgrowth during the patient's first years of life. Exomphalos, macroglossia and gigantism are the main clinical symptoms. CASE DESCRIPTION: The authors describe a 15-year follow-up in a patient with BWS. They focus on a multidisciplinary approach to treating the patient's oral manifestations from age 9 months. The approach included an initial physiotherapy treatment, a partial glossectomy, a first phase of orthopedic treatment with a tongue crib and chin cap, and a second phase of orthodontic treatment with an edgewise appliance. CLINICAL IMPLICATIONS: To obtain long-term positive and stable results, an appropriate treatment plan for patients with BWS and dentoskeletal alterations, including macroglossia, requires surgical tongue reduction when the patient is young, combined with physiotherapeutic phases and orthopedic and orthodontic treatment.

New immature hominin fossil from European Lower Pleistocene shows the earliest evidence of a modern human dental development pattern.

Here we present data concerning the pattern of dental development derived from the microcomputed tomography (microCT) study of a recently discovered immature hominin mandible with a mixed dentition recovered from the TD6 level of the Gran Dolina Lower Pleistocene cave site in Sierra de Atapuerca, northern Spain. These data confirm our previous results that nearly 1 million years ago at least one European hominin species had a fully modern pattern of dental development with a clear slowdown in the development of the molar field regarding the anterior dental field. Furthermore, using available information about enamel formation times and root extension rates in chimpanzees, early hominins, and modern humans, we have estimated that the formation time of the upper and lower first molars of individual 5 (H5) from TD6, which had just erupted at the time of the death of this individual, ranges between 5.3 and 6.6 y. Therefore, the eruption time of the first permanent molars (M1) in the TD6 hominins was within the range of variation of modern human populations. Because the time of M1 eruption in primates is a robust marker of life history, we suggest, as a working hypothesis, that these hominins had a prolonged childhood in the range of the variation of modern humans. If this hypothesis is true, it implies that the appearance in Homo of this important developmental biological feature and an associated increase in brain size preceded the development of the neocortical areas leading to the cognitive capabilities that are thought to be exclusive to Homo sapiens.

Maxillary and mandibular base size in ancient skulls and of modern humans from Opi, Abruzzi, Italy: a cross-sectional study.

AIM: The size and shape of the jaws are related to occlusion and masticatory muscle function. Consequently, teeth and muscles are considered the functional matrix for the two jaws. Existing studies did not focus on the relationship between maxillary and mandibular base but on just their absolute dimensions. As the relationship between the two is of interest to orthodontists, the aim of this study was to calculate the maxillary-mandibular ratio (m-m ratio) in individuals from Central Italy and to compare it to that of ancient skulls from the same geographic area. METHODS: Forty individuals from Opi, a small, isolated mountain village in Central Italy, and 40 ancient skulls from the same region were the sample of this study. The lengths of the maxillary and mandibular base were assessed on lateral cephalograms, the m-m ratio was calculated, and the measurements between the groups were compared. RESULTS: Due to a significantly shorter maxillary base in the modern human sample, the m-m ratio was significantly lower in these subjects. CONCLUSION: This finding supports the hypothesis that growth of the skull is strongly modulated by the functional matrix, within which a morphologic unit develops.

Timing of myofunctional appliance therapy.

OBJECTIVE: To identify the stage of skeletal maturity, as depicted by the Cervical Vertebrae Maturity Index at which the maximal response to myofunctional therapy could be expected. DESIGN: The soft copies of pre and post treatment lateral cephalometric radiographs of the sample comprising of 48 subjects, on myofunctional therapy, were traced on 'Nemotec Dental Studio NX'software. Three groups were formed based on the stages of skeletal maturity and comparison was done. RESULTS: The treated samples were compared with control samples consisting of subjects with untreated Class II malocclusions, also selected on the basis of stages in cervical vertebrae maturation. Inter-group comparison of the treated samples revealed statistically significant changes in Group II (Stages 3 to 4 of Cervical Vertebrae Maturity Index). CONCLUSION: Maximum response to myofunctional therapy can be expected in patients during the stages 3 to 4 of cervical vertebrae maturation index, i.e., during or slightly after the pubertal peak.

Non-invasive 3D facial analysis and surface electromyography during functional pre-orthodontic therapy: a preliminary report.

OBJECTIVES: Functional orthodontic devices can modify oral function thus permitting more adequate growth processes. The assessment of their effects should include both facial morphology and muscle function. This preliminary study investigated whether a preformed functional orthodontic device could induce variations in facial morphology and function along with correction of oral dysfunction in a group of orthodontic patients in the mixed and early permanent dentitions. MATERIAL AND METHODS: The three-dimensional coordinates of 50 facial landmarks (forehead, eyes, nose, cheeks, mouth, jaw and ears) were collected in 10 orthodontic male patients aged 8-13 years, and in 89 healthy reference boys of the same age. Soft tissue facial angles, distances, and ratios were computed. Surface electromyography of the masseter and temporalis muscles was performed, and standardized symmetry, muscular torque and activity were calculated. Soft-tissue facial modifications were analyzed non-invasively before and after a 6-month treatment with a functional device. Comparisons were made with z-scores and paired Student's t-tests. RESULTS: The 6-month treatment stimulated mandibular growth in the anterior and inferior directions, with significant variations in three-dimensional facial divergence and facial convexity. The modifications were larger in the patients than in reference children. In several occasions, the discrepancies relative to the norm became not significant after treatment. No significant variations in standardized muscular activity were found. CONCLUSIONS: Preliminary results showed that the continuous and correct use of the functional device induced measurable intraoral (dental arches) and extraoral (face) morphological modifications. The device did not modify the functional equilibrium of the masticatory muscles.

Non-invasive 3D facial analysis and surface electromyography during functional pre-orthodontic therapy: a preliminary report

OBJECTIVES: Functional orthodontic devices can modify oral function thus permitting more adequate growth processes. The assessment of their effects should include both facial morphology and muscle function. This preliminary study investigated whether a preformed functional orthodontic device could induce variations in facial morphology and function along with correction of oral dysfunction in a group of orthodontic patients in the mixed and early permanent dentitions. MATERIAL AND METHODS: The three-dimensional coordinates of 50 facial landmarks (forehead, eyes, nose, cheeks, mouth, jaw and ears) were collected in 10 orthodontic male patients aged 8-13 years, and in 89 healthy reference boys of the same age. Soft tissue facial angles, distances, and ratios were computed. Surface electromyography of the masseter and temporalis muscles was performed, and standardized symmetry, muscular torque and activity were calculated. Soft-tissue facial modifications were analyzed non-invasively before and after a 6-month treatment with a functional device. Comparisons were made with z-scores and paired Student's t-tests. RESULTS: The 6-month treatment stimulated mandibular growth in the anterior and inferior directions, with significant variations in three-dimensional facial divergence and facial convexity. The modifications were larger in the patients than in reference children. In several occasions, the discrepancies relative to the norm became not significant after treatment. No significant variations in standardized muscular activity were found. CONCLUSIONS: Preliminary results showed that the continuous and correct use of the functional device induced measurable intraoral (dental arches) and extraoral (face) morphological modifications. The device did not modify the functional equilibrium of the masticatory muscles.

Craniofacial growth in children affected by juvenile idiopathic arthritis involving the temporomandibular joint: functional therapy management.

UNLABELLED: The aim of this study was twofold: 1) to asses the effects of a functional appliance on condyles damaged by juvenile idiopathic arthritis (JIA). and 2) to evaluate its ability to reduce alterations in craniofacial development. STUDY DESIGN: Seventy-two JIA patients with temporomandibular involvement, ages ranging between 4 and 16 years, were treated. All of them presented temporomandibular joint involvement. They were treated with an activator and followed for 4 years. RESULTS: At the second examination, it was possible to observe a reduction in mandibular retrusion and in the sagittal discrepancy between mandible and maxilla, a reduction in the angle of divergence, a counterclockwise rotation of the mandible, a reduction of the gonial angle, a longer mandibular ramus, a reduction in the discrepancy between anterior and posterior height caused by an increase in posterior height and a forward positioning of the chin. CONCLUSION: The functional appliance reduces the severity of facial alterations improving mandibular and condylar growth.

Non surgical treatment of a Class II malocclusion with skeletal hyperdivergency and anterior open bite.

The malocclusions with hyperdivergent vertical growth patterns are more difficult to treat without a combined approach, including orthodontics and orthodontic surgery. The goal of this article is to describe a nonsurgical approach of a Class II malocclusion on an adult patient presenting a skeletal hyperdivergency. Fundamental criteria must be respected including proper diagnosis, proper treatment timing to maximize growth potential, patient cooperation, etc. These factors are critical in the favorable treatment outcome of any jaw discrepancy.

Morphometric analysis of the skull of the Sahel goat breed: basic and clinical anatomy.

The work reports morphometric analysis of the skulls of the Sahel breed of goat. The calculated metric data (mean +/- SD) included the condylobasal length, 16.94 +/- 1.39 cm, while the orbital circumference was 11.30 +/- 0.48 cm. The foramen magnum height and width were 1.82 +/- 0.11 cm and 1.85 +/- 0.15 cm respectively while the foramen magnum index was 89.81 +/- 8.71. Animals above one year of age had significantly higher values for orbital length including horizontal and vertical diameters, overall skull length, basal length, and neurocranium height than animals aged one year and below. The cornual process length, maximum orbital circumference and horizontal diameter obtained in this study were higher than those reported for other Nigerian goat breeds in the literature. The data for the distances from the facial tuberosity to the infraorbital canal, from the mental foramen to the lateral extent of the alveolar root of the lower incisor, as well as from the mandibular foramen to the base of the mandible and that from the mental foramen to the caudal border of the mandible, which are important clinically in the estimation of craniofacial measurements that will aid regional anaesthesia, were however similar to those reported earlier for the Red Sokoto and West African Dwarf breeds implying that a uniform craniometric estimation for associated regional nerve blocks can be attempted for these goat breeds.

Static magnetic field combined with functional appliances: a new approach to enhance mandibular growth in Class II malocclusion.

Class II malocclusion is one of the most common orthodontic problems. The main aetiology of Class II malocclusion is mandibular retrognathia. A variety of functional appliances have been used to stimulate mandibular growth in adolescence, however, the effects remain unsatisfactory. Therefore, new approaches are in need to strengthen the effects of functional appliances. Static magnetic field (SMF), created by permanent magnets, has long been proven to be clinically safe and is well accepted as a practical and non-invasive therapy. Numerous experimental and clinical data suggest that exogenous SMF can make profound effects on a large variety of biological systems. There has been increasing interest in curing bone injuries with SMF. More recently, literatures shed light on the chondrogenic and osteogenic effects of SMF. SMF and functional appliances may well have a synergistic effect in mandibular growth promotion. Based on experimental results and theoretical analysis, it is hypothesized that SMF combined with functional appliances can enhance mandibular growth in Class II malocclusion. A practical clinical design is also put forward.

Neuromuscular diagnosis in orthodontics: effects of TENS on the sagittal maxillo-mandibular relationship.

AIM: This study was conducted in order to assess the changes in the occlusal position of the mandible after ULF (Ultra Low Frequency)-TENS relaxing procedure in subjects in pubertal growth phase with diagnosed Angle Class II division 1 and mandibular dentoalveolar retrusion. MATERIALS AND METHODS: This study was performed on 19 patients (13 females, 6 males) with an Angle Class II division 1, aged between 10 and 15 years old (mean age 12.26, SD 1.32), characterised by mandible dentoalveolar retrusion and optimal vertical facial dimension, diagnosed by clinical and cephalometric evaluation. Diagnostic neuromuscular registrations were made for all subjects. The casts were mounted on articulator in habitual intercuspal position with a tooth-guided wax bite registration. Reference points were chosen at molar level. Subsequently the same casts were mounted in myocentric position and compared to the habitual intercuspal position, assessing the sagittal shift after TENS procedure. STATISTICS: Mean and standard deviation were calculated on the amount of shifting at the left molar reference point after TENS procedure. Analysis of variance (ANOVA), using STATA statistics package, was carried out in order to evaluate the influence of sex and age on the amount of molar shift. RESULTS: Nine subjects showed, in the sagittal plane, a forward mandibular shift in neuromuscular myocentric position compared to habitual intercuspal position. Six subjects showed no differences between habitual and myocentric position in the sagittal plane. Four individuals showed a backward mandible shift after TENS indicating worsening of the II molar class in the sagittal plane. CONCLUSION: This study suggests that TENS recorded occlusion in subjects with Class II division 1 with mandible dentoalveolar retrusion allows to visualise an unusual trend of growth. The advancements of the mandible were not taken into account. These results could offer new diagnosis and prognosis methods for Class II malocclusions.