Periodontal health of orthodontically extruded impacted teeth. A split-mouth, long-term clinical evaluation.

BACKGROUND: Impaction of front teeth (often upper canines) can result in esthetic, functional, and phonetic problems, in addition to root resorption and chronic or acute infections. Most impacted front teeth can be extruded orthodontically after minor periodontal surgery. The purpose of this retrospective study was to examine the periodontal outcome of surgically exposed and orthodontically extruded impacted teeth compared with the spontaneously erupted contralateral teeth. METHODS: A total of 38 patients, who had been treated by a combined surgical and orthodontic approach (closed eruption technique by same periodontist and 2 associated orthodontists), underwent a periodontal re-examination after 4 to 10 years. Periodontal parameters (plaque and gingivitis indices, probing depth, bleeding on probing, gingival recession and width, bone level, and root resorption) of the orthodontically extruded teeth (test) were scored and compared with those of the contralateral naturally erupted teeth (control) in a masked set-up. RESULTS: No significant differences could be detected between test and control teeth, except for the gingival width, which was 1 mm larger for the spontaneously erupted teeth. CONCLUSIONS: The data indicate that orthodontic extrusion of impacted front teeth does not jeopardize their periodontal health. This procedure appears to be a satisfactory alternative to extraction and/or transplantation.

The effect of the amount of protrusion built into the bionator on condylar growth and displacement: a clinical study.

To evaluate the treatment effects of a variable degree of forward posturing of the mandible incorporated into the Bionator, a study was undertaken on 14 patients with Class II, Division 1 malocclusion, treated for 1 year with a Bionator, maintaining the mandible in an edge-to-edge incisal position (Be group). This group was compared with a matched group of patients treated with the Bionator in whom the mandible was maintained in a "functional maxipropulsion" (Bmax group). Both groups were subdivided further according to sex for selected parameters. Twenty-nine measurements on cephalometric x-ray films taken before and after 1 year of treatment were statistically analyzed. According to this study, "edge-to-edge" protrusion is superior to "functional maxipropulsion" in increasing ramal height. The difference in increase in corpus length after treatment (greater in boys than in girls) was sex related rather than dependent on appliance characteristics. When studying the effect of functional appliances, it is suggested that a patient group be subdivided by sex. After treatment a repositioning of the condyle was found in a more downward and possibly slightly forward direction relative to sella point (S) in both groups. A relocation of the condyle should be considered as another treatment effect of functional appliances. The more important lowering of the condyle found in the Bmax group may partly explain the significant increase in SNB, the 1.6-fold larger decrease in overbite, and the highly significant increase in anterior lower facial height in this group.(ABSTRACT TRUNCATED AT 250 WORDS)