Time filter

Source Type

München, Germany

Seitz O.,Goethe University Frankfurt | Harth M.,Goethe University Frankfurt | Ghanaati S.,Goethe University Frankfurt | Lehnert T.,Goethe University Frankfurt | And 3 more authors.
Journal of Craniofacial Surgery | Year: 2010

Besides bone grafting, transport disk distraction osteogenesis (TDDO) is an alternative approach that can be used for the reconstruction of the mandibular arch after neoplastic surgery. Although several animal experiments are reporting about the applicability of this technique, little is known about its long-term success in human beings. In this study, we report about the successful treatment of patients with defects of their mandibular arch due to tumor resection by means of the external bifocal TDDO. A total of 7 patients (n = 3 with lateral, n = 4 with anterior defects) were followed up for a mean period of 56 months. Although neither adjuvant nor neoadjuvant chemotherapy negatively influenced callus formation, prereconstructive radiation with a dose of 51 Gy led to an insufficient callus formation. The reconstruction of anterior defects was unsatisfying because tensions from the soft tissue on the fragile and rubber-like callus negatively influenced the natural arch shaping.In these cases, additional surgery was often required. However, reconstruction of lateral defects of the mandibular arch was more successful and resulted in functional bone with good quality, in which dental implants could be inserted. The results of this study emphasize that TDDO by means of bifocal distraction provides functional bone comparable to residual bone.Lateral defects of mandibular arch can be better reconstructed, whereas anterior defects often require additional surgery. © 2010 by Mutaz B. Habal, MD.

Ding P.G.F.,Clinic for Oral | Matzer A.R.A.H.,Clinic for Oral | Wolff D.,Clinic for Oral | Mente J.,Clinic for Oral | And 4 more authors.
Dental Materials | Year: 2010

Objectives: "Submicron hiatus" represents a potential space between the base of the collagenous network and the mineralized dentin when it is acid etched for bonding. This study evaluated the relationship between microtensile bond strength (μTBS) and occurrence of submicron hiatus formations at the resin-dentin interface using the same specimens. Methods: Resin-dentin bonded micro-specimens (sticks with a size of 300 μm × 300 μm × 8 mm) were prepared using one of two material combinations (group I: Syntac Classic/Tetric Ceram Cavifil: n = 51 group II: Prime & Bond NT/Tetric Ceram Cavifil: n = 56). After labeling the primer component with a tiny amount of rhodamine-B-isothiocyanate, submicron hiatus formations were imaged nondestructively using a confocal laser scanning microscope (CLSM). Subsequently specimens were subjected to a μTBS test. Results: For the influence of submicron hiatus formations on μTBS with the Syntac Classic group, the nonparametric Spearman's correlation was -0.329 at p = 0.02. For the Prime & Bond NT group, the nonparametric Spearman's correlation was -0.356 at p = 0.007. Analyzing the effect of submicron hiatus on without discriminating by group resulted in a Spearman's correlation coefficient of -0.341 at p = 0.001; μTBS and quality of hybrid layer showed a correlation coefficient of 0.849 at p = 0.001, and μTBS and quality of tag formation showed a correlation coefficient of 0.474 at p = 0.001. Significance: The degree of submicron hiatus formations had an influence on microtensile bond strength for both the Syntac Classic and the Prime & Bond NT group. © 2009 Academy of Dental Materials.

Hohlweg-Majert B.,Clinic for Oral | Ristow O.,Clinic for Oral | Gust K.,Clinic for Oral | Kehl V.,TU Munich | And 2 more authors.
Journal of Cancer Research and Clinical Oncology | Year: 2012

Purpose To examine tissue oxygenation and perfusion of free microvascular grafts after primary reconstruction, regarding outcome for patients received adjuvant radiotherapy and different types of grafts. Patients and methods Free microvascular grafts (n - 48) after primary reconstruction of the head and neck were examined for tissue oxygenation and perfusion over a period of 6 months. 28 patients received adjuvant radiotherapy. Using a laser doppler flowmetry combined with tissue spectroscopy of the Oxygen-to-see® - equipment (LEA Medizintechnik, Giessen), we were able to determine oxygen saturation, hemoglobin concentration, blood flow and blood flow velocity in the graft in each of two tissue depths (2, 8 mm). Different types of graft were compared. Result Comparison of irradiated and non-irradiated grafts showed significant differences in tissue perfusion and oxygenation. Results for all radiated radial and fibula flaps showed no significant (p > 0.05) differences for all reviewed parameters. However, it showed no dose-volume effect with impaired functionality was found for irradiated grafts. Conclusion Mircovascular free tissue grafts show an increased perfusion and oxygenation after radiation compared to non-irradiated grafts. © Springer-Verlag 2012.

Discover hidden collaborations