Search PubMed⌕ Search

Biomedical subjects

A Petersson

Publications and source records attributed to A Petersson.

At least 73 records · Page 4Linked to original sources

Radiographic changes of the temporomandibular joint after oblique sliding osteotomy of the mandibular rami.

64 patients with mandibular prognathism were operated upon with oblique sliding osteotomies of the mandibular rami. The patients were followed with cephalometric and temporomandibular joint (TMJ) radiographs for 3 years. 60% of the TMJs showed skeletal remodelling 3 years postoperatively. The condylar remodelling was significantly correlated to the degree of postoperative displacement of the condyle. The average condyle displacement postoperatively was about 3 mm inferiorly and anteriorly, but the position was almost completely back to normal during the control period, due to a combination of reverse movement of the condyle and remodelling. Mandibular relapse was not correlated to postoperative displacement of the condyle or condylar remodelling. The range of condylar movement was unchanged at follow-up.

Adolescent↗

Computed tomography versus single-contrast arthrotomography in evaluation of the temporomandibular joint disc. A study of autopsy specimens.

The lateral, central and medial parts of 15 right temporomandibular joint autopsy specimens were studied to compare the ability of computed tomography (CT) and single-contrast arthrotomography in diagnosing the disc position and configuration. The radiologic findings were compared with macroscopic findings in a blinded fashion. In the CT examination, the diagnostic accuracy was 40% in determining the disc position and 26.7% in determining the disc configuration. However, in many areas of the joints the disc was not possible to evaluate by CT. With arthrotomography the diagnostic accuracy in determining the disc position was 75.6% and the disc configuration 60%. The sensitivity of CT was 0.45 and of arthrotomography 0.95 for the diagnosis of the disc position. The specificity was 0.87 for CT and 0.76 for arthrotomography. From these results, we conclude that arthrotomography is a reliable aid to diagnosis of TMJ disc changes and that CT cannot replace it.

Adult↗

Effect of intravenous administration of corticosteroids on dentin formation in the adult rat molar.

This study describes the effects of intravenously given corticosteroids on dentin formation in adult rat molars. Six rats twice a day received corticosteroids 20 mg/kg for 8 days, 10 mg/kg for 13 days, and 5 mg/kg for 19 days. Six rats given a heterotopic heart transplant received 10 mg/kg of corticosteroids twice a day for 40-64 days. Six rats were used as controls. Tetracycline was given at the start of the experiment and after 3 wk of treatment. After 40-46 days the rats were killed. Light microscopic examination of the molars showed no differences in the dentin formation or in the predentin zone between the experimental and control rats. In the ultraviolet light microscope two lines of tetracycline were visible along the root canal walls in both experimental groups. There was an obvious distance between the two lines, which indicated formation of new dentin. In the control group no formation of dentin was visible.

Animals↗

Accuracy of radiographic caries diagnosis using different X-ray generators.

Dental X-ray machines utilizing five different combinations of X-ray generators and tube voltages (Philips Oralix 65 kV, Siemens Heliodent EC 60 kV, Siemens Heliodent 70 kV, Soredex Minray DC 60 kV and Soredex Minray DC 70 kV) were compared with respect to the accuracy of radiographic diagnosis of proximal caries. Nine observers diagnosed proximal caries in radiographs of extracted premolars. The findings of the observers were compared to the actual presence or absence of caries. The ROC-curve technique was used to evaluate differences in diagnostic accuracy between the X-ray machines. The results showed small differences in diagnostic accuracy between the different X-ray generators but they proved to be statistically non-significant.

Dental Caries↗

Craniomandibular disorders in chronic orofacial pain patients.

Forty-six patients with chronic orofacial pain were examined by a pain group consisting of specialists from different fields of dentistry. More than half of the patients presented a craniomandibular diagnosis. The pain had diminished or disappeared 1 year after treatment in 46% of the patients as a whole and in 39% of the patients with a craniomandibular diagnosis. Fifty-two percent of the patients with no relief of their chronic pain had a psychiatric diagnosis.

Adult↗

Radiologic examination for location of the mandibular canal: a comparison between panoramic radiography and conventional tomography.

Panoramic radiography was compared with conventional tomography as techniques for visualizing the mandibular canal. Tomography gave a significantly clearer image of the canal at and 1 cm posterior to the mental foramen, while no differences were found between the methods 2 cm posterior to the mental foramen. Thus, tomography could be of great value in locating the mandibular canal before implant surgery in edentulous mandibular posterior segments.

Adult↗

Location of the mandibular canal: comparison of macroscopic findings, conventional radiography, and computed tomography.

Four mandibular specimens were radiographically examined bilaterally to locate the mandibular canal. The following radiographic techniques were used: periapical and panoramic radiography, hypocycloidal tomography, and computed tomography (CT). The distance from the crest of the alveolar process to the superior border of the mandibular canal was measured in millimeters on all radiographs. The specimens were then sectioned, and the location of the mandibular canal (as measured on contact radiographs of the sections) was compared with measurements made on the other radiographs. The results showed that CT gave the most accurate position of the mandibular canal and is therefore probably the best method for preoperative planning of the implant surgery involving the area close to the mandibular canal.

Humans↗

Relationship between clinical and radiologic findings of the temporomandibular joint in rheumatoid arthritis.

The relationship between clinical findings in the craniomandibular system and radiologic findings in the temporomandibular joint was investigated in 101 adults with rheumatoid arthritis. Radiologic changes were correlated with duration and severity of temporomandibular joint symptoms and general joint disease. The radiologic changes were also associated with loss of occlusal support, anterior open bite, and occlusal interferences. Most joints with crepitus exhibited radiologic erosion. Joints with mutilating changes were silent.

Adult↗

Accuracy of the oblique lateral transcranial projection, lateral tomography, and x-ray stereometry in evaluation of mandibular condyle displacement.

Condylar displacement similar to that occurring during and after mandibular ramus osteotomies was simulated in an in vitro study. Three different radiographic methods were used to measure the displacement, and the accuracy of the methods was compared. The stereometric method was more accurate than the plain radiographic methods and permitted measurements in all three dimensions. The oblique lateral transcranial projection was more accurate than lateral tomography, possibly because identification of measurement points in lateral tomography was complicated by the substantial displacement of the condyle.

Craniotomy↗

Condylar displacement after oblique sliding osteotomy of the mandibular rami. A stereometric and plain radiographic study.

Condylar displacement after oblique sliding osteotomy was examined in 8 patients by X-ray stereometry and plain radiography. During the first 8 postoperative weeks the displacement was in a medial/superior/posterior direction. After removal of the intermaxillary fixation a continuous lateral translation was found together with an initial inferior and a minor anterior translation which after 6 months postoperatively changed to a posterior translation. At 12 months postoperatively a difference in findings of condylar position was found between the X-ray stereometric and plain radiographic analyses. We regard this difference as due to the sum of remodelling and method errors.

Adult↗

Relationship of mandibular condylar position to dental occlusion factors in an asymptomatic population.

This article investigates the influence of occlusion on condylar position as seen on TMJ tomograms in a group of 44 young adults with no histories of orthodontic or occlusal therapy and no objective signs of masticatory dysfunction; the sample was screened from a population of 253 students. Nonconcentric condylar position at ICP was a feature of Class II malocclusion with significantly more anterior positions in Class II, Division 1 than in Class I. Condylar position was unrelated to the amount of sagittal RCP-ICP slide, although most slides were less than 0.5 mm. The frequency of lateral slides was low, but was mildly related to bilaterally asymmetric condylar positions. Position was unrelated to the degree of overbite, which ranged from 0 to 10 mm. Bilateral condylar position asymmetry was not related to the direction of dental midline discrepancy, which ranged from 0 to 2 mm. No open bites or mandibular overjets were seen in this asymptomatic normal sample.

Adult↗

Stability of the osteotomy site after oblique sliding osteotomy of the mandibular rami. A stereometric and plain radiographic study.

Displacement of the mandible 2-2 1/2 years after oblique sliding osteotomy of the mandibular rami is reported. Stability of the osteotomy site has been assumed to be complete much earlier, however. In the present stereo radiographic study mobility at the osteotomy site was recorded as late as 2 years after surgery. No sign of delayed healing was recorded in the plain radiographic examination. It seems possible that relapse after oblique sliding osteotomy continues as long as the functional matrix can influence an unstable osteotomy site. As plain radiography does not give full information on the quality of bone, the stability of the osteotomy site can not be assessed by this method.

Adolescent↗