Mandibular lateral deviation induces alteration in vascular endothelial growth factor expression and oxidative stress/nitric oxide generation in rat condyle, synovial membrane and masseter muscle.

OBJECTIVE: We aimed to investigate alteration in cellular signaling mediated by vascular endothelial growth factor (VEGF) and parameters of oxidative stress/nitric oxide generation, superoxide dismutase (SOD) and neuronal nitric oxide synthase (nNOS), underlying altered functional mechanical loading of TMJ (temporomandibular joint) during lateral mandibular deviation. DESIGN: Thirty-eight 5-week-old male Wistar rats were divided into experimental group, which received acrylic resin appliance that shifted mandible to the left during closure, and control group. Computed tomography and histomorphometry were used for condyle analyses, while samples of condyle, synovial membrane and m. masseter were analyzed with enzyme-linked immunosorbent assay and spectrophotometry to determine VEGF and nNOS protein concentrations, and SOD activity. RESULTS: Experimental group of rats developed smaller and asymmetrical mandibles. Less of new bone and cartilage formation and larger bone marrow cavities area were found in the experimental group. Higher VEGF expression in condyle and m. masseter as well as higher nNOS expression in m. masseter and synovial membrane were found in the experimental compared to the control group. Alteration of SOD activity was found in m. masseter and synovial membrane in the experimental group. CONCLUSIONS: Lateral mandibular deviation induces mandibular and condylar morphological changes as well as significant cellular signaling alterations in condyle, synovial membrane and masticatory muscle. Cellular VEGF protein overexpression and oxidative stress/nitric oxide disbalance could be the mechanisms underlying unbalanced functional TMJ loading due to mandibular deviation.

Relationship between the vertical craniofacial disproportions and the cervicovertebral morphology in adult subjects.

INTRODUCTION: Orthodontic diagnosis includes the interpretation of the relations between the craniofacial and cervical system, given the potential impact of the irregularities from one system to another. OBJECTIVE: The aim of this study was to examine morphological characteristics of the cervical spine, depending on the parameters of the vertical craniofacial growth and gender in adult subjects. METHODS: The sample comprised lateral cephalograms of 120 subjects with different vertical facial growth, aged 17.5-35 years. Measured parameters were the following: anterior and posterior vertebral body height (ABHC2-C5, PBHC2-C5), anterior and posterior intervertebral space (AISC2-C5, PISC2-C5), distance between vertebrae and point sella (SC2, SC3, SC4), pterygomaxillare (PmC2), gonion (GoC2) and basion (BaC4); cervical spine angulation (OPT/CVT) and inclination (OPT/HOR, CVT/HOR). RESULTS: Results showed that subjects with anterior facial growth rotation have greater values for BaC4, OPT/HOR, CVT/HOR, OPT/CVT, anterior and posterior vertebral body heights and intervertebral spaces, and lower values for GoC2 and PmC2. Higher values in males were found for anterior and posterior vertebral body heights, distances SC2, SC3, SC4, and BaC4. In females, the greater values were found for GoC2 and OPT/CVT. CONCLUSION: Subjects with anterior facial growth rotation have greater cervical spine inclination and angulation, higher cervical vertebrae and intervertebral spaces, longer upper cervical spines and shorter distances GoC2 and PmC2. Males show smaller cervical column curvature, but higher cervical vertebrae and greater length of the upper cervical spine.

Changes in soft tissue profile using functional appliances in the treatment of skeletal class II malocclusion.

INTRODUCTION: The effects of orthodontic treatment are considered to be successful if the facial harmony is achieved, while the structures of soft tissue profile are in harmony with skeletal structures of neurocranium and viscerocranium. In patients with skeletal distal bite caused by mandibular retrognathism, facial esthetics is disturbed often, in terms of pronounced convexity of the profile and change in the position and relationship of the lips. OBJECTIVE: The aim of this study was to determine the extent of soft tissue profile changes in patients with skeletal Class II malocclusion treated with three different orthodontic appliances: Fränkel functional regulator type I (FR-I), Balters' Bionator type I and Hotz appliance. METHODS: The study included 60 patients diagnosed with skeletal Class II malocclusion caused by mandibular retrognathism, in the period of early mixed dentition. Each subgroup of 20 patients was treated with a variety of orthodontic appliances. On the lateral cephalogram, before and after treatment, the following parameters were analyzed:T angle, H angle, the height of the upper lip, the position of the upper and lower lip in relation to the esthetic line.Within the statistical analysis the mean, maximum, minimum, standard deviation, coefficient of variation, two-factor analysis of variance with repeated measures and the factor analysis of variance were calculated using ANOVA, Bonferroni test and Student's t-test. RESULTS: A significant decrease of angles T and H was noticed in the application of FR-I, from 21.60° to 17.15°, and from 16.45° to 13.40° (p < 0.001). FR-I decreased the height of the upper lip from 26.15 mm to 25.85 mm, while Hotz appliance and Balters' Bionator type I increased the height of the upper lip, thereby deteriorating esthetics of the patient. CONCLUSION: All used orthodontic appliances lead to changes in soft tissue profile in terms of improving facial esthetics, with the most distinctive changes in the application of Fränkel's functional regulator type I, which is the most successful appliance for achieving the overall facial harmony of the patient.

Changes in Cervical Lordosis and Cervicovertebral Morphology in Different Ages with the Possibility of Estimating Skeletal Maturity.

INTRODUCTION: During growth, proportions of craniofacial and cervical structures are changed. Craniofacial and cervicovertebral structures are morphologically and functionally connected, but their each other's influence is still unknown. OBJECTIVE: The aim of this study was to determine the changes in cervical lordosis and cervicovertebral morphology in different age periods and the possibility of estimating skeletal maturity, based on the percentage of anterior cervical vertebrae body height sum in the total anterior C2-C5 height. METHODS: The study included lateral radiographs of 120 patients of both sexes, divided into three different age groups: eight, 12-13 and 17-18 years of age. Five craniofacial and 15 cervical parameters were measured and analyzed. RESULTS: The results showed significant correlation between cervical lordosis angle and age, gender, anterior and posterior body height of C3, C4, C5, anterior C4-C5 and posterior C2-C3, C3-C4, C4-C5 intervertebral space, anterior body height of C2-C5. Overall values of all cervical body heights were more present in the total height of the spine in females, while all intervertebral spaces were more present in males. The percentage of anterior and posterior C2, C3, C4, C5 body height sum compared to total C2-C5 height increases with age. CONCLUSION: The cervical lordosis becomes more curved and vertebral bodies occupy more space in females, while intervertebral spaces occupy more in males. Skeletal maturity could be estimated following vertebral percentage distribution in the total anterior C2-C5 part.

[Orthodontic treatment of nongrowing patient with Class II Division 2 malocclusion by Herbst appliance].

BACKGROUND: Inheritance is most casual etiological factor of Class II division 2 malocclusion. This kind of malocclusion is very difficult for treatment specially in older patients. CASE REPORT: In the female patient, 20 years old, at the beginning of the treatment at the School of Dentistry in Belgrade, lateral cephalogram showed skeletal and dentoalveolar Class II division 2 malocclusion. She was in the Herbst treatment for 8 months and 12 months more with a fixed multibracket appliance. The measurements were performed on lateral cephalograms before and after the treatment: ii, is, mi, ms, Pg and ss. The distance from these points to occlusal perpendicular line (Olp) were measured and compared from cephalogram before to cephalogram after the treatment. Temporomandibular joint (TMJ) tomograms were compared from before and after the treatment by superimposition. Correction was found in molar and incisor relation, overjet and overbite. There were found sagital skeletal changes and soft tissue profile improvement. CONCLUSION: Herbst appliance is effective in the treatment of Class II malocclusions, even in adult patients. Dental and skeletal changes as a result of Herbst treatment could be good choice instead of camouflage orthodontics or surgical decision.

[Possibilty of the lower third molar eruption--radiographic analysis].

BACKGROUND/AIM: To assess the possibility of the eruption of the lower third molar on the basis of the measured parameters: retromolar space, mesiodistal crown width of a molar and the third molar angulation. METHODS: The investigation included 104 patients both sexes (43 boys, and 61 girls), 16 to 25 years old (mean age, 18 years). It was performed using the orthopanthomographic radiographs analysis of those patients. Each radiograph was covered by tracing paper, and the contoures of the following anatomic details were drawn: a) the crown and root contours of third molars, upper and lower central incisors, distal molars in occlusion, anterior edge of ramus mandible, b) lines: 1. the occlusal plane, 2. the line of retromolar space, 3. the mesiodistal crown width of third molar, 4. the axial shaft of the third molar and the distal angle between occlusal plane and the axial shaft of the third molar. The values were measured with an orthodontic caliper: the diameter of retromolar space, diameter of mesiodistal width, the value of distal angle between occlusal plane and axial shaft of molar. RESULTS: A favourable angulation of the lower third molar (more than 60 degrees) was found in, boys (left 27.90%, right 32.55%), girls (left 39.34%, right 37.77%). A favourable relationship between the diameters of mesiodistal width of the third molar and retromolar space was found in, boys, (left 13.59%, right 16.27%), girls, (left 8.19%, right 14.75%). A favourable relationship between the diameters of mesiodistal width of the third molar and the retromolar space and the angulation was found in boys, (left 9.30%, right 11.62%), girls, (left 6.56%, right 9.83%). CONCLUSION: There was not any statistically significant difference found between the relation of the retromolar value, third molar mesiodistal diameter, or of the third molar angulation to the left and the right side nor of their mutual relations in comparing boys and girls. A favourable prognosis was found in 9.33% of the patients.