Fortschritte der Kiefer- und Gesichts-Chirurgie最新文献

Breakage of the dentoalveolar gomphosis during tooth extraction results in varying amounts of desmodont remaining at the surface of the root. By dying the remnants of desmodont with toluidine blue, the surface of the root can be made accessible to computerized optical analysis. After clinically induced extraction of 102 human teeth, and after the loosening of 24 sheep teeth by mechanical vibration, the remaining area of desmodont was compared to that of the entire surface. Except in one case, no parameters were found to influence the amount of desmodont. However, tooth extraction in sheep previously treated with ultrasound or low-frequency vibrations demonstrate more desmodont-free areas.

In 68 patients, 79 tooth germs of the third molar were transplanted. Out of this group, 43 patients with 50 transplantations under-went a follow-up examination. All surgery was performed by one surgeon. Retrospectively, we tried to establish whether the success of postoperative healing depends on the donor and receiver regions. Crossing the jaw border clearly worsens the prognosis for transplantation. Altogether 9 transplantations turned out to be failures, 7 of which had been transplanted from the upper to the lower jaw. The results of this investigation showed incomplete root development in 34%, the necessity of endodontic treatment in 6% and enlarged periodontal pockets in 8%. Ankylosed teeth were found in 10%; we did not see any root resorptions.

Two collectives of patients who required radiation therapy were built. In order to determine the adequate occasion and extension of surgical teeth restoration in dependence on radiation therapy, both collectives were compared. The first group implicated 21 manifest ORN. The triggers of these ORN were evaluated. In the second collective the ORN occurrence after 225 generous surgical teeth restorations before radiation therapy were prospectively fixed and analysed. In comparison of both collectives the concept of generous removing of all potential dentogene inflammations before radiation therapy was successful in prevention of the septic ORN.

Long-term follow-up of orthopantomographs of 251 adults orthodontically treated former patients showed 113 clinically asymptomatic impacted 3rd molars in 58 patients. Radiographic assessment revealed contact of impacted 3rd molars with the 2nd molars, resorption of upper and lower 2nd molars, reduced bone height on the distal side of the maxillary and mandibular 2nd molars, as well as pathologically widened pericoronal spaces of the upper and lower 3rd molars. The comparison of the sagittal 3rd molar position in 52 impacted teeth revealed a sagittal change in all 3rd molars from post-treatment to follow-up: maxillary and mandibular 3rd molars had rotated to a more upright position and showed an increase in mesio- or distoangulation or a change of axial inclination. The lack of predicting factors such as age, period of impaction, extent of space deficiency, developmental stage, level of eruption, and bone conditions leads the authors to recommend that former orthodontic patients be recalled at regular intervals for assessment of changes in the condition and position of erupting or impacted 3rd molars.

Although uncommon, anterior maxillary supernumerary teeth (mesiodentes) are the most frequent supernumerary teeth. A disturbed or delayed eruption of the adjacent permanent incisors may be due to a mesiodens and should lead to a further radiographic examination. In some cases the exact radiographic location of the mesiodens may prove difficult. The surgical removal of mesiodentes is especially difficult in extreme cranial displacement. The records of 90 patients with 113 mesiodentes are discussed with special reference to their degree of retention, topographical location, width of pericoronal space and surgical removal, and incidence of retention and malposition of the adjacent permanent incisors, respectively.

The indication of therapeutic tooth luxation in partly impacted teeth as the only method of occlusal adjustment has up to the present been rare. It was therefore the aim of this retrospective, long-term study to include clinical and X-ray results following therapeutic molar luxation (OK 6, UK 7). After an average observation period of 5.3 years, all teeth (7) with incomplete root formation at the time of luxation were rated "successful" following molar luxation. On the other hand, only 2 out of 4 teeth were hand, only classified as "successful" following molar luxation with complete root formation. The results have shown that therapeutic tooth luxation for occlusal adjustment of partly retained molars has a high rate of success when the indication is correctly handled. Because the prognosis is determined according to the stage of root formation, the surgical approach of tooth luxation should be used solely in teeth whose root development has the 1/2 to 3/4 of the expected definitive root length and whose Foramen apicale is open at the time of operation. When an atraumatic operation technique is used, further root formation and a maintained sensibility of the pulp can be reckoned with.