Quad-helix treatment in general practice. A retrospective study of failures of appliance and estimation of costs.

From a Public Dental Service register of patients with malocclusion, 1688 patients were selected at random. Ninety-nine patients, 5.9 per cent, had received treatment with quad-helix appliance in General Practice and were selected for the study. From the patient's records the cost of quad-helix treatment was estimated and failure of the appliance was recorded. The mean quad-helix treatment cost was 2900 SEK (range 1298-6534). At the time of the study (1991) 10 SEK was equivalent to approximately 1 pound sterling. Fifty-nine per cent of the patients had at least one failure of the appliance, on average 2.5 number of times (range 1-11). Forty-six per cent of the patients had a minimum of one loose band.

Assessing the costs of activator treatments in general practice.

From a register of patients with malocclusion, 1688 patients were selected, of which 208 (12.3 per cent) had received activator treatment in general practice. Fifteen patients having moved from the area, the remaining 193 patients were selected for the study. From the patients' records, activator treatment time, and the costs of activator and additional orthodontic treatment were estimated. The results of activator treatment were graded according to a three-grade scale. Most activator treatments (83 per cent) had a duration of 2 years or less. Approximately half (48 per cent) of the patients were estimated to have good or excellent results. There was great variation in activator treatment costs and these did not appear to be associated with treatment results. There were also extreme variations between patients in number of visits to the clinic as well as in chairside-time. Additional orthodontic treatments were performed by the GDPs in 55 per cent of the patients and 12 per cent of the patients were referred to orthodontic specialist clinics for treatment.

A histologic comparative study of the midpalatal suture and periodontal ligament tissue in the beagle dog.

The present investigation describes the morphological difference between the suture and the periodontal ligament in beagle dogs. Specimens from five beagle dogs, 2 yr old, containing the anterior portion of the maxilla were used. Following routine histologic preparations frontal sections were cut with the microtome. The sections were stained and studied in the light microscope. The fibers in the midpalatal suture seemed coarser and less organized than the fibers in the periodontal ligament tissue. The vessels in the suture had thicker walls than the vessels in the periodontal ligament. A probable reason for the morphological differences between the two tissues is discussed.

Occurrence and distribution of root resorption in orthodontically moved premolars in dogs.

An experimental study in dogs, in which 15 teeth were bodily moved and 9 teeth were tipped with the same amount of horizontal force. Less resorption was found with tipping, and less was found on the mesial root surfaces moved into the extraction sites than on the furcation side of the distal roots.

Orthodontic movement of maxillary incisor into the midline. A case report.

Orthodontic treatment of a case is presented where an eight year old girl previously had had the upper right central incisor surgically removed because of an odontoma. Orthodontic closure of the space from both sides was performed with fixed appliance, leaving the remaining central incisor in the midline. A retainer was bonded to prevent relapse.