Uso da terapia fotodinâmica, beta-tricálcio fosfato e doxiciclina no reparo alveolar de ratos induzidos a osteonecrose: análise por micro-tomografia, microscopia confocal a laser e histomorfométricas
Carregando...
Data
2022-08-23
Autores
Rodrigues, Letícia Gabriella de Souza [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Os bifosfonatos (BF’s) são medicamentos antirreabsortivos empregados no tratamento de desordens esqueléticas, como a osteoporose, porém seu uso prolongado pode induzir a osteonecrose dos maxilares induzida por medicamentos (OMIM), e o tratamento desta condição representa um desafio para odontologia. O objetivo deste projeto foi avaliar o efeito de terapias preventivas sobre a OMIM, durante o processo de reparo alveolar em ratos. Foram utilizados 72 ratos wistar, os quais foram tratados com 04 aplicações de 0,035 mg/kg de ácido zoledrônico (ZOL) por via caudal com intervalos de 15 dias entre as aplicações e posteriormente tiveram seus molares inferiores direitos removidos. Após a exodontia, os animais seguiram com o tratamento com ZOL no mesmo protocolo até a eutanásia. Os animais foram divididos em nove grupos (n=8) de acordo com o tratamento do alvéolo dental: GS (Sham – não foi aplicado ZOL), GC (Coágulo), Gβ (β- tricálcio-fosfato), GD (gel de doxiciclina a 10%), GP (terapia foto-dinâmica), GDβ (gel de doxiciclina a 10% + β-tricálcio-fosfato), GPβ (terapia foto-dinâmica + β-tricálcio- fosfato), GPD (terapia foto-dinâmica +gel de doxiciclina a 10%), GPDβ (terapia foto- dinâmica +gel de doxiciclina a 10% + β-tricálcio-fosfato). Foi realizado análise in vivo e para a etapa de cortes mineralizados foram utilizados 72 animais, onde após 28 dias da data de exodontia, os animais foram eutanasiados para a avaliação através: 1) aplicação dos fluorocromos (calceína e alizarina) seguido da análise de microscopia confocal a laser, 2) análise microtomográfica e 3) análise histomorfométrica para determinação da porcentagem de osso neoformado (%NBA), tecido conjuntivo e osso sem vitalidade. A microCT demostrou que todos os grupos apresentaram maiores médias de BV/TV quando comparados a GS (42,17% ± 2,65) e o melhor resultado foi de GPDB (69,85% ± 6,25), seguido por GPD e GDB (64,62 ±0,13 e 64,69 ± 4,40), quando comparado ao GC, GS, GP e GPB (P <0,05). GS demostrou sequestros ósseos, enquanto as terapias permitiram o processo de reparo alveolar. A taxa MAR de GPDB apresentou a maior aposição diária (2,64 ± 0,48) quando comparado a todos os grupos (p <0,001), exceto por GDB (p = 0,359), que obteve segundo maior MAR (2,30 ± 0,37). GPDB apresentou a maior média de %NBA (82,44 % ± 2,69), quando comparado a todos os grupos (p < 0,05), seguido pelo grupo GDB (60,82 % ± 4,37) e apenas GS apresentou formação de osso sem vitalidade (37,94 ± 18,70%). Entre os tratamentos aplicados de forma isolada, GB apresentou o melhor %NBA (57,13 % ± 5,89), principalmente quando comparado ao GP (p = 0,022) e GS (p = 0,001). Conclui-se que o protocolo de ZOL aplicado nessa pesquisa foi capaz de induzir a necrose óssea e que o uso das terapias locais no alvéolo dos ratos tratados com ZOL, isoladas ou associadas, foram capazes de prevenir a OMIM.
Bisphosphonates are anti-resorptive drugs used in the treatment of skeletal disorders, such as osteoporosis, but their prolonged use may induce osteonecrosis of the jaw (MRONJ), which represents a challenging treatment for dentistry. The aim of this project will be to evaluate the preventive effect of therapies on MRONJ during the alveolar repair process in rats. For this, 360 wistar rats will be used, which will be treated with 04 applications of 0.035 mg / kg of zoledronic acid (ZOE) through the caudal vein with 15 days intervals between applications and subsequently have their right lower molars removed. After extraction, the animals will continue treatment with ZOE in the same protocol until euthanasia. The animals will be divided into seven groups according to the treatment of the dental socket: GS (Sham – ZOE will apply), GC (blood clot only), Gβ (βtricalcium phosphate), GD (10% doxycycline), GP (photo-dynamic therapy), GDβ (10% doxycycline + β-tricalcium phosphate), GPβ (photo-dynamic therapy + β-tricalcium phosphate), GPD (photodynamic therapy + 10% doxycycline), GPDβ (photo-dynamic therapy + 10% doxycycline + βtricalcium phosphate). . For in vivo analysis, in the calcified cuts will be used 72 animals, where after 36 days from the date of extraction, the animals will be euthanized for evaluation by 1) application of fluorochromes (calcein and alizarin) followed by confocal laser microscopy analysis. and 2) microtomographic analysis end 3) histomorphometric analysis to determine the percentage of mewly formed bone (%NBA), connective tissue and bone without vitality, MicroCT showed that all groups had higher means of BV/TV when compared to GS (42,17% ± 2,65) and the best results was GPDB (69,85% ± 6,25), followed by GPD and GDB GPD e GDB (64,62 ±0,13 e 64,69 ± 4,40), when compared to GC, GS, GP, and GPB (P <0,05). GS demonstrated bone sequestration, while the trerapies enabled the alveolar reoais process. The MAR rate of GPDB had the highest daily apposition (2,64 ± 0,48) when compared to all groups (p <0,001), except for GDB (p = 0,359), which had the second highest MAR (2,30 ± 0,37). GPDB had the highest mean of %NBA (82,44 % ± 2,69), when compared to all groups (p < 0,05), followed by the GDB group (60,82 % ± 4,37) and only GS presented bone formation without vitality (37,94 ± 18,70%). Among the treatments applied in isolation, GB presentead the best %NBA (57,13 % ± 5,89), especially when compared to GP (p = 0,022) and GS (p = 0,001). It is conclued that the ZOL protocol applied in this research was able to induce bone necrosis and that the use of local therapies in the alveolus of rats treated with ZOL, alone or in conbination, were able to prevent OMIN.
Bisphosphonates are anti-resorptive drugs used in the treatment of skeletal disorders, such as osteoporosis, but their prolonged use may induce osteonecrosis of the jaw (MRONJ), which represents a challenging treatment for dentistry. The aim of this project will be to evaluate the preventive effect of therapies on MRONJ during the alveolar repair process in rats. For this, 360 wistar rats will be used, which will be treated with 04 applications of 0.035 mg / kg of zoledronic acid (ZOE) through the caudal vein with 15 days intervals between applications and subsequently have their right lower molars removed. After extraction, the animals will continue treatment with ZOE in the same protocol until euthanasia. The animals will be divided into seven groups according to the treatment of the dental socket: GS (Sham – ZOE will apply), GC (blood clot only), Gβ (βtricalcium phosphate), GD (10% doxycycline), GP (photo-dynamic therapy), GDβ (10% doxycycline + β-tricalcium phosphate), GPβ (photo-dynamic therapy + β-tricalcium phosphate), GPD (photodynamic therapy + 10% doxycycline), GPDβ (photo-dynamic therapy + 10% doxycycline + βtricalcium phosphate). . For in vivo analysis, in the calcified cuts will be used 72 animals, where after 36 days from the date of extraction, the animals will be euthanized for evaluation by 1) application of fluorochromes (calcein and alizarin) followed by confocal laser microscopy analysis. and 2) microtomographic analysis end 3) histomorphometric analysis to determine the percentage of mewly formed bone (%NBA), connective tissue and bone without vitality, MicroCT showed that all groups had higher means of BV/TV when compared to GS (42,17% ± 2,65) and the best results was GPDB (69,85% ± 6,25), followed by GPD and GDB GPD e GDB (64,62 ±0,13 e 64,69 ± 4,40), when compared to GC, GS, GP, and GPB (P <0,05). GS demonstrated bone sequestration, while the trerapies enabled the alveolar reoais process. The MAR rate of GPDB had the highest daily apposition (2,64 ± 0,48) when compared to all groups (p <0,001), except for GDB (p = 0,359), which had the second highest MAR (2,30 ± 0,37). GPDB had the highest mean of %NBA (82,44 % ± 2,69), when compared to all groups (p < 0,05), followed by the GDB group (60,82 % ± 4,37) and only GS presented bone formation without vitality (37,94 ± 18,70%). Among the treatments applied in isolation, GB presentead the best %NBA (57,13 % ± 5,89), especially when compared to GP (p = 0,022) and GS (p = 0,001). It is conclued that the ZOL protocol applied in this research was able to induce bone necrosis and that the use of local therapies in the alveolus of rats treated with ZOL, alone or in conbination, were able to prevent OMIN.
Descrição
Palavras-chave
Osteonecrose, Fotoquimioterapia, Doxiciclina, Alvéolo dental, Osteonecrosis