OBJECTIVES: It is important to know the etiology of implant failure. It has been reported that heat stress during drilling was one of the causes for failure and the threshold was 47 degrees C. However, clinically, we encounter cases in which overheating does not seem to affect osseointegration eventually. The purpose of this study was to assess histologically the spatio-temporal effect of heat stress on bone formation after overheating the bone matrix. MATERIAL AND METHODS: Rat calvarial bone was heated to 37 degrees C, 43 degrees C, 45 degrees C and 48 degrees C for 15 min by a temperature stimulator. Paraffin sections were prepared 1, 3 and 5 weeks after heating and investigated histologically under light microscopy. Hematoxylin and eosin staining, alkaline phosphatase (ALP), osteopontin (OPN), heat shock protein 27 (Hsp27) and heat shock protein 70 (Hsp70) immunohistochemistry and tartrate-resistant acid phosphatase (TRAP) enzyme histochemistry were carried out. The area of dead osteocytes was calculated and statistically analyzed. Apoptotic osteocytes were detected by the terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL) method. RESULTS: Along with the temperature increase, the area of dead osteocytes increased and regeneration of the periosteal membrane was delayed. Hsps- and TUNEL-positive cells were only seen in the 48 degrees C group. Spatio-temporal changes of TRAP- and ALP-positive cell numbers were observed, while OPN expression was mostly absent. Even after 48 degrees C stimulation, bone formation on the calvarial surface was observed after 5 weeks. CONCLUSIONS: Although there was a temperature-dependent delay in bone formation after heat stress, the 48 degrees C heat stress did not obstruct bone formation eventually. This delay was probably caused by slow periosteal membrane regeneration.
OBJECTIVES: It is important to know the etiology of implant failure. It has been reported that heat stress during drilling was one of the causes for failure and the threshold was 47 degrees C. However, clinically, we encounter cases in which overheating does not seem to affect osseointegration eventually. The purpose of this study was to assess histologically the spatio-temporal effect of heat stress on bone formation after overheating the bone matrix. MATERIAL AND METHODS:Rat calvarial bone was heated to 37 degrees C, 43 degrees C, 45 degrees C and 48 degrees C for 15 min by a temperature stimulator. Paraffin sections were prepared 1, 3 and 5 weeks after heating and investigated histologically under light microscopy. Hematoxylin and eosin staining, alkaline phosphatase (ALP), osteopontin (OPN), heat shock protein 27 (Hsp27) and heat shock protein 70 (Hsp70) immunohistochemistry and tartrate-resistant acid phosphatase (TRAP) enzyme histochemistry were carried out. The area of dead osteocytes was calculated and statistically analyzed. Apoptotic osteocytes were detected by the terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL) method. RESULTS: Along with the temperature increase, the area of dead osteocytes increased and regeneration of the periosteal membrane was delayed. Hsps- and TUNEL-positive cells were only seen in the 48 degrees C group. Spatio-temporal changes of TRAP- and ALP-positive cell numbers were observed, while OPN expression was mostly absent. Even after 48 degrees C stimulation, bone formation on the calvarial surface was observed after 5 weeks. CONCLUSIONS: Although there was a temperature-dependent delay in bone formation after heat stress, the 48 degrees C heat stress did not obstruct bone formation eventually. This delay was probably caused by slow periosteal membrane regeneration.
Authors: Ming Li; Sabine Fuchs; Thomas Böse; Harald Schmidt; Alexander Hofmann; Marcus Tonak; Ronald Unger; Charles James Kirkpatrick Journal: Tissue Eng Part C Methods Date: 2013-10-05 Impact factor: 3.056
Authors: Luke J Mortensen; Clemens Alt; Raphaël Turcotte; Marissa Masek; Tzu-Ming Liu; Daniel C Côté; Chris Xu; Giuseppe Intini; Charles P Lin Journal: Biomed Opt Express Date: 2014-12-05 Impact factor: 3.732
Authors: David D Lo; Mark A Mackanos; Michael T Chung; Jeong S Hyun; Daniel T Montoro; Monica Grova; Chunjun Liu; Jenny Wang; Daniel Palanker; Andrew J Connolly; Michael T Longaker; Christopher H Contag; Derrick C Wan Journal: Lasers Surg Med Date: 2012-11-26 Impact factor: 4.025
Authors: Gabriela Giro; Nick Tovar; Charles Marin; Estevam A Bonfante; Ryo Jimbo; Marcelo Suzuki; Malvin N Janal; Paulo G Coelho Journal: Int J Biomater Date: 2013-01-30
Authors: Carlo Fornaini; Marco Meleti; Mauro Bonanini; Giuseppe Lagori; Paolo Vescovi; Elisabetta Merigo; Samir Nammour Journal: ScientificWorldJournal Date: 2014-07-03
Authors: Georg Bergmann; Friedmar Graichen; Jörn Dymke; Antonius Rohlmann; Georg N Duda; Philipp Damm Journal: PLoS One Date: 2012-08-22 Impact factor: 3.240