Biomedical subjects
Publications and source records attributed to M Ritzau.
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The effect of a single preoperative dose of metronidazole in the prevention of alveolitis sicca dolorosa (ASD) after surgical removal of one impacted, non-infected mandibular third molar was investigated. A patient sample of 270 were given either 1000 mg of metronidazole or placebo at least 30 min before surgery. The preoperative recordings included gender, age, tooth to be removed, experience of surgeon, time of test medication, and duration of surgery. No difference was found between the metronidazole and placebo groups in the occurrence of ASD. The duration of surgery and the experience of the operating surgeons had no effect on the occurrence of ASD. The present study failed to demonstrate any preventive effect of a single dose of metronidazole on the development of ASD.
The purpose of the study was to assess skeletal stability following combined surgical-orthodontic management of 52 adults with severe mandibular prognathism. Lateral cephalograms taken 1 week before surgery, within 1 week post-surgery and approximately 1 year after operation were studied by means of eight variables and a constructive stable reproducible reference system. The surgical procedure of choice was a bilateral vertical ramus osteotomy through an extra-oral approach. In all cases the condyles were left passively in the articular fossa and no attempt at their active repositioning was made. The patients were randomly allocated to an osteosynthesis or non-osteosynthesis group with regard to intramandibular fixation. Intermaxillary fixation lasted 6 weeks and an interocclusal wafer was used in all cases during this period. The findings of this study showed that during the post-operative period there was a trend for posterior rotation of the mandibular corpus (P less than 0.001). This pattern was also characterized by an increase (P less than 0.001) of the lower anterior face height and an improvement of the angle of convexity (P less than 0.001). These changes occurring in a direction so that the dentoskeletal profile became less concave, did not tend to reverse the goal of operation and cannot be considered as detrimental. No significant differences (P greater than 0.05) were found between the groups without and with osteosynthesis.
A novel class of butyrolactones, named obscurolides, was isolated from the culture filtrate of Streptomyces viridochromogenes by chemical screening methods. The structural elucidation of the obscurolides A1 to A4 (1 approximately 4) is described. The carboxy group of the 4-aminobenzoic acid moiety of obscurolide A1 (1) is reduced in the other compounds. The isolated natural products have been proved to be diastereomeric mixtures by a partial racemization at C-7 which belongs to an allylic alcohol system. The obscurolides showed a weak inhibitory activity against calcium/calmodulin-dependent and independent phosphodiesterases from bovine.
The present investigation studied changes of hyoid bone position and pharyngeal depth at the levels of the second and fourth cervical vertebrae and their relationships in mandibular prognathism patients who received combined orthodontic-surgical treatment. The material consisted of presurgical and 1-year postsurgical profile cephalograms of 52 adult orthognathic surgery patients (40 females and 12 males) who initially had mandibular prognathism and had undergone bilateral vertical ramus osteotomy through an extraoral incision in the retroangular area. Hyoid bone position and pharyngeal depth were assessed on the profile radiographs with 10 cephalometric variables. Paired t tests were used to evaluate the operative changes in all cephalometric parameters. The relationships between pairs of variables describing hyoid bone position and pharyngeal depth were assessed by means of Pearson's product-moment correlation analysis. Significant differences (p less than 0.01) were observed for the distances of the hyoid bone to the maxilla and the mandible. The distances of the hyoid bone with the anterior cranial base, the vertebral column, and the anterior pharyngeal wall, and the measurements representing pharyngeal depth exhibited no significant changes (p greater than 0.05). Moderate correlations were seen between (1) the depth of the pharynx at the fourth cervical vertebra and the hyosymphyseal distance (r = 0.34) and the distance between the point of the projection of the hyoid bone to the mandibular line with its posterior border (r = -0.34), and (2) the depth of the pharynx at the second cervical vertebra and the distance of the hyoid bone with the anterior pharyngeal wall at the level of the fourth cervical vertebra (r = -0.33).(ABSTRACT TRUNCATED AT 250 WORDS)
A case of recurrence of a chondromyxoid fibroma 3 years after its surgical removal is presented. The significance of the clinical, radiographic and histological appearances is discussed.
The purpose of the present study was to elucidate the importance of ramal osteosynthesis and evaluate postoperative condylar movements. The right temporomandibular joints of 53 patients with mandibular prognathism were examined by linear tomography the day before, 1 week after, and 1 year after surgery. During surgery the patients were randomly allocated to two groups: one with (n = 26) and one without (n = 27) osteosynthesis. It was found that osteosynthesis did not influence condyle position (p greater than 0.3). The two groups were thereafter pooled. Radiographic measurements of the posterior and anterior interarticular space revealed that condyle position 1 week postoperatively was forward and downward in relation to the preoperative position (posterior fossa, p less than 0.001; anterior fossa, p less than 0.01). One year later the condyle position demonstrated a tendency to approximate the preoperative position, especially with respect to the posterior part, but there was still a significant (p less than 0.01) difference when related to the original position. In conclusion, osteosynthesis after ramus osteotomy seems to be of no importance when healing and postoperative condyle position are considered. Furthermore, 1 year after surgery the condyles were not reestablished in their preoperative positions.
The aim of the present study was to illustrate a possible relationship between changes in craniofacial morphology after mandibular osteotomy and changes in head posture and nasopharyngeal airway size. The material comprised standardized profile cephalograms of 52 patients with mandibular prognathism, all of whom underwent orthodontic adjustment before mandibular osteotomy. Mean age of the patients was 24.3 years; 12 men and 40 women participated in the study. The first profile radiograph of each patient was taken 1 day before surgical treatment in the natural head (mirror) position. All patients underwent mandibular surgery with a bilateral vertical ramus osteotomy. The cephalometric investigation was repeated approximately 1 year after the surgical procedure (means = 1.12 years). Craniofacial morphology was evaluated by 12 parameters describing sagittal and vertical jaw relationship. Head posture was evaluated by the craniocervical angulation and airway as nasopharyngeal airway size. Pearson's correlation analysis was used to evaluate the relationship between morphology, posture, and airway size before surgery and changes in these parameters after surgery. Before surgical treatment statistically significant correlations were found between posture and many morphologic variables, mostly mandibular. Small correlations were observed between posture and airway size, and airway size and morphology. After the surgical procedure, changes in posture were still related to changes in mandibular morphology, while other correlations between posture and morphology had been eliminated. Changes in nasopharyngeal airway size were not correlated to any changes in morphology, apart from maxillary prognathism, nor to changes in posture. The results indicated that mandibular morphology and function play a significant role in determining head posture.
It was the aim of the present study to cast light on the role of the mandible in relation to head posture and airway space by evaluating patients before and after surgical correction of mandibular prognathism. The material comprised standardized profile cephalograms of 52 patients with mandibular prognathism. All patients had received orthodontic adjustments prior to mandibular osteotomy. Mean age of the patients was 24.3 years, and 12 males and 40 females participated in the study. The first profile radiograph of each patient was obtained the day before surgery in the natural head (mirror) position. All patients underwent mandibular surgery with a bilateral vertical ramus osteotomy. Approximately one year after surgery, the cephalometric investigation was repeated. Head posture was evaluated by the craniocervical angulation (NSL/CVT and NSL/OPT) and airway space as nasopharyngeal airway size (ad1 and ad2). Changes in posture and airway (ex.2-ex.1) were evaluated by paired t-tests. The results showed a mean increase in head posture of 2.7 degrees (p less than 0.001) and a mean reduction in airway space of 2.3 mm (p less than 0.001).
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In a double-blind study dental cones containing the antifibrinolytically active propylic ester of p-hydroxybenzoic acid (PEPH), sulfanilamide and sulfathiazol or placebo were placed in dental sockets following removal of impacted mandibular third molars on 95 consecutive patients, 50 women and 45 men. The duration of the operation, the type of surgeon, preoperative symptoms and the use of peroral anticonception were recorded. The patients were asked to return to the clinic on the seventh postoperative day, and it was then noted whether the healing was disturbed by Alveolitis Sicca Dolorosa (ASD) or not. Statistical analysis showed a significantly prophylactic effect of PEPH against ASD. The prophylactic effect was most pronounced in the group of male patients without preoperative symptoms and in the group of patients operated by dental students. It could not be demonstrated that the sulfa drugs in the cones were of any benefit to the healing of the socket.
A double-blind experiment was performed to test the possible prophylactic effect of the antifibrinolytically active propylic ester of p-hydroxybenzoic acid (PEPH) on alveolitis sicca dolorosa (dry socket). Tablets containing PEPH or placebo were inserted at random selection into the alveoli of forty-five consecutive patients, each of whom had had an impacted mandibular third molar removed. The prophylactic effect of PEPH in this study was found to be highly significant as compared to that of placebo, and no patients in the experimental group developed alveolitis sicca dolorosa.
A teaching model, specially constructed for the purpose of training senior dental students in the use of surgical instruments, is described. The advantages of this model are inexpensiveness and reproducible simulated surgical situations securing a uniform teaching objective.
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