Rate of tooth movement and dentoskeletal effects of rapid canine retraction by dentoalveolar distraction osteogenesis: A prospective study.

INTRODUCTION: The purpose of this study was to test the null hypothesis that duration of orthodontic treatment can be significantly reduced by accelerating canine retraction using dentoalveolar distraction (DAD). METHODS: Thirty-six maxillary canines of 19 patients comprised the DAD group, and 28 canines of 14 patients were included in the distalization group (DG). The initial mean ages were 15.8 ± 1.96 years for the DAD group and 16.02 ± 2.8 years for the DG. A custom-made, rigid, tooth-borne intraoral distraction device was used for the DAD group, and intraoral elastics were applied for canine distalization in the DG. Six skeletal and 11 dental variables were measured for the cephalometric evaluation. RESULTS: Canine retraction was 7.9 ± 1.49 mm in 11.8 ± 1.3 days and canine distal tipping was 11.48° ± 4.37° after DAD; the canines were distalized 5.29 ± 2.01 mm and tipped 13.64° ± 9.54° in 200 ± 57 days in the DG. The rates of posterior canine movement were 0.67 ± 0.14 mm per day after DAD and 0.03 ± 0.01 mm per day in the DG. No significant first molar anchorage loss was observed after DAD, although the DG showed some vertical and sagittal first molar movement. CONCLUSIONS: We failed to reject the null hypothesis. DAD can reduce the duration of orthodontic treatment time by accelerating canine retraction in extraction patients without undesirable side effects.

Six-Year Survival of a Mini Dental Implant-Retained Overdenture in a Child with Ectodermal Dysplasia.

Patients with ectodermal dysplasia (ED) experience several problems caused by abnormal development and functioning of the head and neck region. In addition to developmental nasal cartilage abnormalities and absence of sweat glands, hair, and eyebrows, edentulism or developmental disorders of teeth (cone-shaped teeth) are commonly observed in these types of patients. ED is also characterized by underdeveloped alveolar ridges, a decreased occlusal vertical dimension, reduced salivary secretion, and dry oral mucosa, which make prosthetic rehabilitation difficult. Few studies of intraosseous dental implant-retained prostheses have described adverse effects on craniofacial growth and esthetic and functional disadvantages, while some researchers have described the advantages of this treatment option as an alternative option in these cases. Due to the associated alveolar bone deficiency, dental mini-implant therapy may be a treatment option for these patients; however, there are isolated cases in the literature regarding the rehabilitation of ED patients with mini-implant-supported overdentures. This clinical report describes the rehabilitation of a 6-year-old child with ED using a maxillary removable partial prosthesis and a mini-implant-retained mandibular overdenture. The clinical and radiographic findings of this prosthetic rehabilitation during the 6-year follow-up are also presented.

Dystrophic calcifications arising in the masseter muscle: a case report.

Calcium salt deposits in the presence of normal calcium/phosphorus metabolism involving tissues that do not physiologically calcify are referred to as dystrophic calcification. The condition may be associated with a variety of systemic disorders. Additionally, injured tissue of any kind is predisposed to dystrophic calcification. The case of a 21-year-old man with two isolated dystrophic calcifications in the right masseter muscle is presented. Dystrophic calcifications should be studied carefully and differentiated from lesions resulting from other syndromes that manifest calcification of soft tissues. The lack of a classification system of soft tissue calcifications complicates the management and study of the condition.

The effects of osteoformin on mineralisation and quality of newly formed bone during mandibular distraction osteogenesis in rabbits.

OBJECTIVE: The aim of this experimental study was to evaluate the effects of osteoformin on mineralization and quality of newly formed bone during distraction osteogenesis in rabbits. STUDY DESIGN: Distraction rate was as 1 mm/day for 5 days. In the experimental group, 100 microg/kg osteoformin in 100 microL/kg phosphate-buffered saline (PBS) was injected into the distraction area at day 1 and day 7 after surgery. In the control group, only 100 microL/kg PBS was injected on the same days. On day 42, the animals were killed. RESULTS: Bone mineral density and bone mineral content values increased significantly in the experimental group (P < .05). Newly formed bone areas, number of vessels and osteoblasts were significantly greater in experimental group (P < .05). The number of fibroblasts were also greater, but it was not significant statistically (P > .05). The number of osteoclasts was significantly lower in experimental group (P < .05). CONCLUSION: The results of this study show that osteoformin improves healing of regenerate in distraction osteogenesis in rabbits.

Effects of alendronate on rate of distraction in rabbit mandibles.

PURPOSE: Bisphosphonates are used for inhibiting bone resorption in several diseases. In this experimental study, the effects of alendronate on the mandibular distraction gap in rabbits at 2 different rates were evaluated. MATERIALS AND METHODS: The study was performed using 15 New Zealand white rabbits. Group 1 consisted of animals with distraction at the rate of 1 mm/day. Group 2 consisted of animals with distraction at the rate of 2 mm/day. These experimental groups had a postoperative alendronate injection during the first 3 days of their distraction phase. Group 3 consisted of animals with distraction at the rate of 1 mm/day, without alendronate injections. Distraction was performed on only the left sides of all animals until a gap of 10 mm was achieved. On postoperative day 45, the animals were sacrificed, and the mandibles of all animals were evaluated radiographically and histologically, and with dual-energy x-ray absorptiometry (DEXA). Radiographic images were also evaluated using transmission densitometry (TD). RESULTS: Histologically, bone healing was found to be significantly accelerated in groups 1 and 2 compared with group 3 (P < .05). Bone healing was superior in group 2, but the difference was not statistically significant compared with group 1. The TD results revealed no statistical difference between experimental groups, whereas the results for group 2 showed significantly denser osteogenic formation in the distraction gap compared with group 3. There was a significant increase in mean bone mineral density in the experimental groups compared with the control group. CONCLUSION: Histologic, TD, and DEXA results showed that alendronate injections during the distraction phase may be effective in accelerating new bone formation in the distraction gap in rabbit mandibles. The TD results also support the concept that an administration of alendronate may allow a 2 mm/day elongation instead of 1 mm/day in the rabbit mandible.

Difficulties in anesthetic management of patients with micrognathia: report of a patient with Stickler syndrome.

Stickler syndrome is an autosomal dominant multisystem disorder with characteristic midface hypoplasia, retromicrognathia, cleft palate and a "moon-shaped" appearance. Progressive myopia and retinal degeneration are frequent. It is estimated that one third of all Pierre Robin patients have Stickler syndrome. Patients with a mandibular hypoplasia like Stickler syndrome present the anesthesiologist considerable problems when mask ventilation or endotracheal intubation is attempted. In this case report the difficulties in anesthetic management of patients with micrognathia and repeated anesthetic courses of a child with Stickler syndrome are presented. It is vital to detect the syndrome in early stages so that adequate counseling and treatment may be given to avoid the potentially irreversible and disabling consequences.