Comparison of the effects of passive posterior bite-blocks with different construction bites on the craniofacial and dentoalveolar structures.

Posterior bite-blocks that are used in the early treatment of skeletal open bite, produce a forward and upward mandibular rotation by transmitting the masticatory muscle forces to the buccal dentoalveolar regions and preventing their vertical growth. Increasing the vertical dimension of the face artificially causes skeletal adaptations to occur not only in the dentoalveolar region but also in the other regions of the craniofacial complex. The affects of passive posterior bite-blocks, constructed in two different heights, were investigated for two treatment groups, in comparison to an untreated control group. Two treatment groups comprised of 25 growing patients, who had skeletal open bite and skeletal/dental Class I or Class II malocclusions, and one control group consisting of 14 growing patients were used. These groups were matched concerning their age, sex, and vertical and sagittal skeletal cephalometric and dental characteristics. Passive posterior bite-blocks of 5 and 10 mm heights were applied to the subjects of the treatment groups respectively for 18 hours per day. Untreated control subjects were observed for 7 to 9 months. The findings of this study revealed that the downward and backward mandibular rotation continued in the control group, increasing the lower facial height significantly, whereas in the treatment groups, the skeletal open bite was treated and the mandible rotated upward and forward. The increase of the height of the posterior bite-blocks had a significant effect on the anterior mandibular rotation and in the increase of the gonial angle.

The effects of different sectional arches in canine retraction.

The purpose of the present study was to compare the effects of Gjessing's canine retraction arch with a sectional arch including a reverse closing loop, which are both used for canine retraction in extraction cases. Our study involved both the maxilla and the mandible independently. After upper first premolar extractions and levelling of the teeth with 0.018-inch slot standard Edgewise appliances on 12 subjects, with a mean age of 15 years, the right maxillary canines were retracted by 0.016 x 0.022-inch sectional arches including a reverse closing loop, for a mean period of 7.75 months whereas the left maxillary canines were retracted by 0.016 x 0.022-inch Gjessing retraction arches for a mean period of 6.25 months. Following lower first premolar extractions and levelling of the teeth in eight subjects with a mean age of 13 years 7 months, the right mandibular canines were retracted by 0.016 x 0.022-inch sectional arches with reverse closing loop for a mean period of 7.75 months and the left mandibular canines were retracted by 0.016 x 0.022-inch Gjessing arches for a mean period of 6 months. The present study was carried out on 40 lateral cephalometric films of 20 subjects taken prior to and at the end of canine retraction. The differences between the mean changes of the sectional arch including reverse closing loop and Gjessing retraction arch groups were found to be statistically significant for the amount of upper canine crown retraction, mesial movement of upper first molar crown and duration and rate of upper canine distal movement.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of the spring-loaded posterior bite-block on the maxillo-facial morphology.

The purpose of this study was to determine the effects of the spring-loaded bilateral posterior occlusal bite-block on the maxillo-facial morphology, with emphasis on the response of the facial structures to the progressively increased vertical dimension. Our sample consisted of two groups: eleven open-bite subjects having a mean age of 10.30 years, treated with spring-loaded posterior bite-blocks over a mean period of 0.49 +/- 0.08 years (6 months); and twelve open bite subjects with a mean age of 9.84 years, treated by means of passive posterior bite-block and vertical chin-cap for a mean period of 0.67 +/- 0.03 years (8 months). The average daily use of the appliances was 16 hours. The study was carried out on lateral head films taken prior to and after treatment, which was concluded when an overbite of 1-1.5 mm was achieved. The results did not reflect any statistically significant difference between the groups when considering the changes in the horizontal growth pattern of the mandible, the decrease of the lower and the total anterior facial heights, or the overbite achieved by the two types of posterior bite-blocks. The artificial increase of the vertical dimension contributed to a statistically significant increase in the ramal inclination in both groups, though greater in the spring-loaded posterior bite-block group.

[Effects of lower canine distalization with sectional arches on the positions of lower incisors and molars]. / Alt kaninlerin bölümlü arklar ile distalizasyonlarinin alt keser ve molar dis konumlarina etkisi.

The purpose of the study was to investigate the effects of lower canine distalization with .016 x 0.016 inch sectional arches on the positions of lower incisors and first permanent molars. Study was carried out on two lateral cephalograms taken at the beginning of treatment and at the end of canine distalization over a period of six months, from each of 17 subjects having a chronological age range of 11 years 8 months and 19 years and whose treatments with first premolar extraction were begun with .018 inch slot std. edgewise technique. Due to the mean lower canine distalization of 3 mm. till spacing of lower anteriors, mean lower incisor retrusion of 0.9 mm. concurrent with a mean decrease of 0.9 mm. in Holdaway difference were occurred which were both found to be statistically significant. Mesial movement of lower first permanent molars having a mean of 0.3 mm was not found to be significant.

Relation of ectodermal dysplasia and hypodontia.

Ectodermal dysplasia and hypodontia were diagnosed in three families who referred to Gazi University Pedodontic Department in 1989. From the view point of dentistry, it is intended to point out the genetic transitive character of ectodermal dysplasia and its possible relation with hypodontia. Also; some approaches to satisfy the patients in social and psychological aspects besides replacing the functional and cosmetic demands were carried out.

[Study of the structural compensation of the mandible during treatment with cervical headgear]. / Servikal headgear ile tedaviye karsi alt çenede görülen yapisal kompanzasyonun arastirilmasi.

This study was performed on two cephalometric films of each fourteen subjects with skeletal class 1 facial structure and Angle Class II molar relation treated with cervical headgear for a period 0.777 +/- 0.06 years; and of each thirteen control subjects with skeletal class 1 facial structures and normal occlusion observed for a period of 0.807 +/- 0.03 years. The correlation coefficients for the longitudinal changes of angular and linear measurements during control and treatment periods in both groups were evaluated. The correlation coefficients belonging to each group were compared; and the compensational regions during cervical traction were investigated. It was concluded that; the structural compensations occurred in the mandible according to the inhibition of the mesial migration of lower permanent first molars because of the interdigitation with the upper ones were the increase in the ramus inclination, change in the growth pattern of the mandibular condyle, increases in the gonial angle, lower anterior facial height and the mandibular plane angle.

[The dental picture and maxillo facial skeletal morphology in idiopathic hypoparathyroidism (a case report)]. / Idiyopatik hipoparatiroidide dis bulgulari ve çene-yüz iskelet morfolojisi (Bir vaka raporu).

In this paper a case showing idiopathic hypoparathyroidism with its rare dental findings were presented. Abnormalities belonging to maxillo-facial skeletal morphology was also evaluated by means of cephalometric analysis.

[The use of spring-loaded posterior bite-block in the treatment of open-bite]. / Açik kapanis tedavisinde yayli arka isirma blogu (spring-loaded posterior bite-block) uygulamasi.

The treatment objectives of open-bite cases which occurs as a result of the excess vertical growth of nasomaxillary complex, increase in the upper and lower posterior vertical dentoalveolar development, downward and backward growth of the mandible are restraining of the growth capacity of these regions and leading the growth of the mandible on the horizontal plane. One of the treatment alternatives of these cases is the spring-loaded posterior bite block; a functional orthopedic appliance. In this case report which the effects of spring-loaded posterior bite block therapy on craniofacial and dentoalveolar structures have been shown; three cases having chronological ages of 9 years 8 months; 10 years 4 months and 10 years 1 month were presented and the treatment results were discussed. The common effects of spring-loaded posterior bite-block therapy observed in three cases are; the restraint of the vertical growth of the maxilla and of both lower-upper posterior dentoalveolar structures, change in the growth pattern of the mandible from vertical towards horizontal plane.