Cryopreserved tissue engineered mucosa.

Single cells suspensions used for grafting in the clinical setting may be reliably cryopreserved by established protocols. However, for tissue engineered constructs which now also get used as grafts in the clinic such established protocols and assays which indicate graft viability and their function as graft do not exist. a) The purpose was to develop a cryoprotocol and an animal model to test the efficacy of tissue engineered to act as graft after cryopreservation. b) Therefore, tissue engineered mucosa grafts consisting of keratinocytes and fibroblasts grown in a collagen sponge were cryopreserved and grafted in the nude rat to test its efficacy to function as mucosa graft. At different points after cryopreservation the mucosa was grafted into the nude rats. Healing of grafts was allowed for one or three weeks. c) Sufficient cells survived the cryopreservation allowing for the development of epithelial-fibroblast tissue in the collagen sponge. After three weeks of healing the formation of mucosa tissue was more complete and more collagen sponge had disappeared. d) The nude rat model is suitable to assess the efficacy of tissue engineered mucosa to function as graft after cryopreservation. The formation of human epithelial-fibroblast tissue in vivo has to be interpreted as proof of principle that the approach of cryopreservation of tissue engineered grafts is working

Der "Frühe Patientenkontakt" im Studiengang Zahnmedizin [Community Dentistry and early patient contact at the department of dentistry at the University of Greifswald]

[english] The "Early Patient Contact" is a relatively new "Teaching Concept" enabling students to receive an insight early on their studies about patient contact and treatment possibilities. Within the one year visiting program the students had "Hands-on" experience with "real patients". Through accompanying lectures using the "Problem-based learning method" (PBL) students were able to learn about the principles of Community Medicine/Dentistry within the Health Service, and about population relevant illnesses. An evaluation form part of a Questionaire made evident that it is possible to provide considerable improvement of the medical/dental education as regards communication skills and understanding of the patients' perceptions, by letting the student establish contact with patients at the very beginning of the curriculum. The students found that experience of high importance. [german] Das Lehrkonzept "Der Frühe Patientenkontakt" für den Studiengang der Zahnmedizin wird im Rahmen der Community Medicine/Dentistry an der Universität Greifswald durchgeführt. Die Lehreinheit erstreckt sich über die ersten vier vorklinischen Semester. Die wesentliche Zielstellung besteht darin, den Studierenden bereits zu Beginn des Zahnmedizinstudiums einen Patientenkontakt zu ermöglichen und somit das Zahnmedizinstudium frühzeitig patientennah zu gestalten. Sie lernen einen "Echt-Patienten" und dessen Lebenssituation über den Zeitraum von einem Jahr kennen. Anhand von begleitenden Vorlesungen und Seminaren wird das Prinzip der Community Medicine/Dentistry erläutert und die Studierenden werden mit bevölkerungsrelevanten Erkrankungen und Gesundheitsstrukturen bekannt gemacht. Dabei wird unter anderem die Lehrmethode "Problemorientiertes Lernen" angewendet. Das Lehrprojekt wird zu Beginn und zum Abschluss mittels eines speziellen Evaluationsbogens ausgewertet. Die Ergebnisse zeigen, dass die Studierenden den "Frühen Patientenkontakt" zu Beginn des Studiums mehrheitlich positiv bewerten. Das Projekt ermöglicht den Teilnehmern erste Erfahrungen im dialogischen Beziehungsaufbau und einen Einblick in die komplexe Persönlichkeitsstruktur eines "echten Patienten". Die Studierenden halten es für wichtig, bereits frühzeitig reale "Patientenwirklichkeiten" kennen zu lernen

Comparison of craniofacial morphology in patients with unilateral cleft lip, alveolus and palate with and without secondary osteoplasty

Problem What kind of skeletal differences do exist between juvenile patients with unilateral cleft lip, alveolus and palate treated with or without secondary osteoplasty, and between cleft patients and non-cleft patients? Patients and methods Thirty-nine patients with unilateral cleft lip, alveolus and palate at a mean age of 15.8 years who were surgically treated with (n = 18) and without (n 21) secondary osteoplasty were compared with a control group of non-cleft patients (mean age 15.1 years). The patients were analyzed using lateral cephalograms. Cephalometric analysis included common sagittal and vertical variables as well as measurements of anterior tooth position and soft-tissue profile. Results Analysis of lateral cephalograms revealed no significant differences between the two groups of cleft patients. The differences in comparison with the control group mainly revealed maxillary retroposition, a vertically open configuration, a steep position of the upper and lower anterior teeth and a decreased Holdaway-angle (flat midface). Conclusion Secondary osteoplasty exhibited no significant influence on craniofacial growth in children with unilateral cleft lip and palate. Both groups of cleft patients are not markedly different regarding sagittal and vertical skeletal configurations.No Full Tex

Variations in the Inclination of the Condylar Path in Children and Adults

Objective: To test the null hypothesis that there are no differences between children and adults in the condylar path inclination angle on the right and left sides. Materials and Methods: A group of 80 children aged 6 to 10 years (subgroups I through V, according to chronologic age) was compared with an adult group with regard to the condylar path inclination angle (CPIA) on the right and left sides. The CPIA was measured using the ultrasonic JMA-System for registration. Results: During development of the temporomandibular joint the condylar path inclination angle increased with age in the subgroups of children. A significant difference was found in the CPIA between the groups of adults and children. In the group with the oldest children (mean age: 10.3 years) the condylar path inclination angle had reached 81.87% on the right side and 78.85% on the left side compared with the adult group at a 5 mm protrusive path. In the pooled group of children the CPIA amounted to 73.08% on the right side and 72.13% on the left side compared with the values for the adults. No significant difference was found between the right and left CPIA in any group. Conclusion: The hypothesis is rejected. The CPIA on the right and left sides increased with age in the group of children and was significantly smaller in the group of children compared with the group of adults. (Angle Orthod. 2009;79:958-963.

Morphofunctional changes of orofacial muscles in patients with unilateral or bilateral cleft lip, alveolus and palate

The facial musculature is part of a biocybernetic feedback system within the stomatognathic system, the continuity of which is disturbed by clefts of the lip, jaw, and palate (cheilognathopalatoschisis). This results in topographic, fine-structural and functional alterations of the facial musculature. In two heads with unilateral clefts and two heads with bilateral clefts, the facial musculature was dissected and the M. orbicularis oris macroscopically and topographically examined. We found changes in the attachment of the M. orbicularis oris. The modiolus, which is coresponsible for the proper topographic relation of the M. obicularis oris to the other facial muscles, was unchanged. Further, we examined the vascular system of the muscle, which likewise adapts to the altered situation. Lip/jaw/palatal clefts result in anatomically functional and fine-structural alterations of the M. orbicularis oris, while the rest of the facial musculature remains unchanged.No Full Tex

Shear and tensile bond strength comparison of various contemporary orthodontic adhesive systems: An in-vitro study

Introduction: The purpose of this study was to compare the shear and tensile bond strengths of 8 common adhesive systems for bonding in orthodontics. Methods: One hundred sixty freshly extracted bovine mandibular permanent incisors were randomly divided into 8 groups. Self-ligating esthetic Damon 3 brackets (Ormco, Orange, Calif) were bonded by using the following adhesive systems: Quick Bond (chemically and light-cured; Forestadent, Pforzheim, Germany), Blugloo (Ormco), Enlight LV (Ormco), Kurasper F (Kuraray Dental, Frankfurt, Germany), Transbond LR (3M Unitek, Monrovia, Calif), Light Bond (Reliance Orthodontic Products, Itasca, III), and Fuji Ortho LC (GC America, Alsip, III). After 24 hours, half of each group was debonded measuring the shear bond strength and half measuring the tensile bond strength. Results: Blugloo showed the best shear bond strength values, whereas Transbond LR and Quick Bond (chemically and light-cured) had the lowest. Tensile strength was the highest with Fuji Ortho LC and the lowest with Quick Bond (chemically and light-cured) and Kurasper F. The tensile strength of light-cured Quick Bond was about 47% lower than that of Fuji Ortho LC. Conclusions: Blugloo, Fuji Ortho LC, Light Bond, and Enlight LV are among the materials of choice for bonding fixed orthodontic appliances to teeth. All bond strength values were clinically satisfactory except for the tensile strength of chemically and light-cured Quick Bond and Kurasper F. (Am J Orthod Dentofacial Orthop 2009; 135: 422.e1-422.e6