The effect of changes in lower incisor inclination on gingival recession.

AIM: Orthodontic treatment may promote development of recessions. The mechanism by which orthodontic treatment influences occurrence of recessions remains unclear. The aim of this study was to test the hypothesis that a change of mandibular incisor inclination promotes development of labial gingival recessions. MATERIALS AND METHODS: The study sample comprised dental casts and lateral cephalograms obtained from 109 subjects before orthodontic treatment (Tb) and after orthodontic treatment (Ta). Depending on the change of lower incisor inclination during treatment, the subjects were divided into three groups: Retroclination (R), Stable Position (S), and Proclination (P). The presence of gingival recessions of mandibular incisors and clinical crown heights were assessed on plaster models. RESULTS AND CONCLUSIONS: From Tb to Ta, Inc_Incl showed a statistically significant change in the R, P, and S groups (p < 0.05). Increase of clinical crown heights of the lower incisors (42, 4, and 31) was not statistically significant in any group. The only statistically significant intergroup difference was the greater increase of the clinical crown height of tooth number 32 in the P group in comparison with the R group (p = 0.049). The change of lower incisor inclination during treatment did not lead to development of labial gingival recessions in the study sample.

Reliability of four different computerized cephalometric analysis programs.

The aim of this investigation was to compare the traditional method of manual cephalometric tracing with four different computerized tracing programs, where the lateral cephalograms were scanned at 300 dpi and digitized onscreen. Thirty randomly selected cephalometric radiographs were used in this study. Four programs Dolphin Imaging, Vistadent, Nemoceph, and Quick Ceph were evaluated. Three dental, 11 skeletal, and 1 soft tissue parameters were measured that consisted of 5 linear and 10 angular measurements. Statistical analysis was carried out using multivariate analysis of variance and Box's and Levene's tests. No statistically significant difference was found between manual tracing and the computerized tracing programs. The measurements obtained with the cephalometric analysis programs used in the study were reliable.

Long-term effects of rapid maxillary expansion followed by fixed appliances.

OBJECTIVE: To evaluate the long-term changes in maxillary arch widths, overjet, and overbite in patients who were treated with rapid maxillary expansion (RME) followed by edgewise appliances. MATERIALS AND METHODS: The material for the study consisted of study casts taken from 41 patients (19 males, 22 females) on four different occasions (before treatment, T1; after RME, T2; after treatment, T3; and during follow-up period, T4). The upper intercanine, interpremolar, and intermolar widths and overjet and overbite were measured on each set of study casts. Mean age of the subjects was 13.2 +/- 1.3 years (range, 11.2-16.9 years) at T1, 13.3 +/- 1.3 years (range, 11.3-17 years) at T2, 15.5 +/- 1.4 years (range, 13.1-18.8 years) at T3, and 20.4 +/- 1.6 years (range, 17.9-24.8 years) at T4. RESULTS: The net increase in intercanine width, interpremolar width, intermolar width, overjet, and overbite was 1.4 +/- 2.4 mm, 4.6 +/- 2.6 mm, 4.3 +/- 2.5 mm, 0.1 +/- 0.6 mm, and 0.2 +/- 0.6 mm, respectively, and the relapse rates were 37% for intercanine width, 19% for interpremolar width, and 17% for intermolar width at the end of the follow-up period. CONCLUSIONS: A significant amount of relapse occurred in maxillary arch widths at the postretention assessment, the greatest being in intercanine width. RME significantly decreased overbite and increased overjet, and a statistically significant decrease was observed in both overbite and overjet at the postretention assessment.

Six year follow-up of a patient treated with mandibular symphyseal distraction osteogenesis.

In this report, treatment and long term effects of mandibular symphyseal distraction osteogenesis (MSDO) on dentofacial structures are presented. The distraction device used in the present case was a custom made tooth- and bone-borne distractor. Post-treatment records revealed elimination of mandibular anterior crowding, no temporomandibular joint (TMJ) disorder, no periodontal pathology and no root resorption. Follow-up records taken 6 years after the completion of the treatment indicated no mandibular anterior crowding or TMJ disorder. Treatment and long term results of this case suggest that mandibular widening with distraction osteogenesis is an efficient, safe and stable treatment modality for patients presenting transverse mandibular deficiency and/or mandibular anterior dental crowding. However, large sample studies are required to draw substantial conclusions about the long term effects of the MSDO on dentofacial structures.

Correction of Mandibular Retrognathia and Laterognathia by Distraction Osteogenesis: Follow up of 5 cases.

This article evaluates the use of distraction osteogenesis in the treatment of mandibular retrognathia and laterognathia and the long term treatment results of the patients treated with this technique. The procedure was carried out in 5 subjects (3 males and 2 females, mean age 18.4 years) aged between 14 years and 27 years. In patients treated with bilateral mandibular distraction, it was observed that the ANB angle decreased by a mean of 5 degrees , the mandibular corpus length increased by a mean of 14.5 mm and the overjet decreased by a mean of 12.2 mm after treatment. In patients treated with unilateral mandibular distraction, a mean of 3.5 degrees reduction was achieved in ANB angle, the mandibular corpus length increased by a mean of 5.5 mm and a mean of 7 mm correction was achieved in relation to craniofacial midline with treatment. One of these patients showed an increase of 10 mm in ramus height on the affected side and a decrease of 5 degrees in gonial angle whereas the other one showed an increase of 12.5 degrees in gonial angle and an increase of 11 mm in ramus height on the affected side after treatment. The most significant long term relapse was observed in one of the patients treated with bilateral mandibular distraction. Long term relapse seen in the rest of the patients was within clinically acceptable limits. It can be concluded that distraction of the deformed mandible is a feasible and effective technique for treating mandibular retrognathia and laterognathia. However, it must be borne in mind that accurate placement of the distractors and determining the correct distraction vector are crucial factors that have an influence on long term clinical success.

Transient bacteremia after removal of a bonded maxillary expansion appliance.

INTRODUCTION: The aim of this study was to investigate the presence of transient bacteremia after the removal of a modified bonded rapid maxillary expansion appliance. METHODS: The sample consisted of 25 subjects (15 girls, 10 boys; mean age, 14.4 years; range, 12.2-16.6 years). All subjects underwent rapid maxillary expansion at the start of the orthodontic treatment with the same type of appliance. Two 10-mL blood samples were taken, the first as a baseline and the second 3 minutes after removal of the appliance. All blood samples were incubated in an automated blood culture system, and bacteria were identified by using conventional biochemical methods and API kits (bioMérieux, Marcy l'Etoile, France). RESULTS: Overt soft-tissue bleeding was observed in 11 of the 25 patients during appliance removal, and 8 of 25 patients showed bacteremia after appliance removal. The data were analyzed with the Fisher exact test. No statistically significant relationship was found between overt bleeding and bacteremia incidence (P = 0.054). CONCLUSIONS: Because transient bacteremia is caused by trauma from the removal of the modified bonded rapid maxillary expansion appliance, orthodontists should consider the possibility of bacterial endocarditis in at-risk patients when using splint-type tooth-and-tissue-borne rapid maxillary expansion appliances.

Craniofacial morphology in children with operated complete unilateral cleft lip and palate.

The objective of the study was to compare the craniofacial characteristics of children with operated unilateral complete cleft lip and palate (UCLP) with those of noncleft children. Lateral and posteroanterior cephalometric radiographs of subjects with UCLP and controls who were matched for sex, age, and ethnic origin were analyzed and compared. There were a total of 21 subjects with UCLP (10 boys and 11 girls) from the Orthodontic Department of Selcuk University and 15 controls (7 boys and 8 girls) from the Orthodontic Department of Ankara University. The nasal bone length in the group with cleft did not differ significantly from that in the control group. Subjects with UCLP included in the study appeared to have shorter faces, smaller mandibulae, greater lateral orbital width, and smaller sella turcicae compared with controls. Unilateral cleft lip and palate affects the intracranial morphology as well as dentofacial structures.

Rapid canine distalization through segmental alveolar distraction osteogenesis.

OBJECTIVE: The objectives of this study were to achieve rapid canine distalization by segmental alveolar distraction method in first premolar extraction cases, to examine the changes in the periodontal tissues surrounding canines, to evaluate the displacement of the canine and first molar teeth, to assess the effects of the procedure on the pulpal vitality of the canines, and to determine the amount of root resorption in retracted canines. MATERIALS AND METHODS: The sample of the study consisted of 20 teeth in eight patients (four females and four males, mean age 18.5 years). Pre- and posttreatment dental casts, panoramic radiographs, and standard periapical radiographs were taken from all patients. An electrical vitality test was applied before and after the distraction procedure and during the follow-up period (6 months after the completion of the procedure). In addition, six periodontal indices were used to examine the health of the periodontal tissues. RESULTS: The distraction procedure was completed in 12 to 28 days (mean 14.65 +/- 3.49). The anchorage loss ranged from 0 to 3 mm (mean 1.2 +/- 0.83). The distal displacement of the canines ranged from 3 to 8 mm (mean 5.35 +/- 1.22). The canines showed a mean of 9.1 degrees distal tipping, whereas there was no statistically significant change in the axial inclinations of first molars after distraction. CONCLUSION: We believe that rapid canine distalization by segmental distraction osteogenesis will become a routine protocol and a popular method among orthodontic applications.