ABSTRACT
OBJECTIVE: The purpose of this study was to evaluate the contribution of a bioresorbable membrane placement to the healing of immature teeth after autotransplantation of tooth buds. STUDY DESIGN: Six cases were selected: 2 transplantations of wisdom teeth, 2 for premolar agenesis, 1 for ectopia, and 1 premolar in an incisor position. The crown of each tooth germ and the marginal alveolar bone were covered with a resorbable membrane. RESULTS: The radicular edification was nearly complete, neither ankylosis nor inflammatory resorption was observable, the pulp vitality was preserved, and the periodontal integration was identical to that of other teeth. The membrane ensured contention and stabilization of the transplant, allowed functional stimulation, permitted protection of the coagulum and periodontal cells, and kept the epithelium at a distance. CONCLUSIONS: The transplantations of immature teeth were improved by the use of a resorbable membrane, which caused an optimal functional fixation of the transplanted tooth.
Subject(s)
Guided Tissue Regeneration, Periodontal , Membranes, Artificial , Tooth Germ/transplantation , Tooth/transplantation , Absorbable Implants , Adolescent , Adult , Bicuspid/transplantation , Child , Female , Follow-Up Studies , Humans , Male , Molar/transplantation , Polyglactin 910 , Transplantation, Autologous/methodsABSTRACT
In vertebrates, only few experiments have been performed in microgravity to study the embryonic development from fertilization. To date, these concern only amphibian and fish. We report here a study on the embryonic development of Pleurodeles waltl (urodele amphibian) eggs oviposited in microgravity. The experiment was performed twice on board the Mir space station and the data obtained included video recording and morphological, histological and immunocytological analyses. The data confirm that the microgravity conditions have effects during the embryonic period, particularly during cleavage and neurulation, inducing irregular segmentation and abnormal closure of the neural tube. Moreover, we observed several abnormalities hither to undescribed corresponding to cortical cytoplasm movements, a decrease of cell adhesion and a loss of cells. These abnormalities were temporary and subsequently reversible. The young larvae that hatched during the flight displayed normal morphology and swimming behavior after landing. The results obtained in the urodele Pleurodeles waltl are in accordance with those observed earlier in the anuran Xenopus laevis and in the fish Oryzias latipes.
Subject(s)
Embryo, Nonmammalian/physiology , Nervous System/embryology , Pleurodeles/physiology , Space Flight , Weightlessness , Animals , Cell Physiological Phenomena , Choline O-Acetyltransferase/metabolism , Cleavage Stage, Ovum , Embryo, Nonmammalian/abnormalities , Embryonic Development , Female , Larva , Motor Activity , Ovum , Pleurodeles/abnormalities , Pleurodeles/embryology , Pleurodeles/growth & development , SwimmingABSTRACT
The German-French biological experiment AQUARIUS-XENOPUS which flew on the Soyuz flight Andromede to the International Space Station ISS (launched October 21, 2001 in Baikonour/Kazakhstan) was extended by an outreach project. Pupils of class 10 to 12 from Ulm/D and Nancy-Tomblaine/F studied swimming behavior of Xenopus tadpoles on ground. They were instructed to perform all experimental steps following the protocol of similar video recordings on ISS. After the flight, they evaluated the kinetics of swimming of both ground controls and space animals. The pupil project included theoretical components to introduce them to the field of gravitational biology. One feature of the project was the exchange of ideas between pupils by meetings which took place in Ulm (June 2001), Nancy (February 2002) and Paris (May 2002). We consider our approach as a successful way to include young people in space experiments on a cheap cost level and to bring ideas of gravitational biology into the curricula of European schools.