摘要
Abstract
Objective:To investigate the effects of erbium:yttrium aluminium garnet (Er:YAG)laser irradiation on pulp and formation of dentin bridge.The beagle dogs'coronal pulp is amputated by Er:YAG laser.Methods:In the study,24 premolar teeth of two one-year-old Beagle dogs were used.They were divided into 3 groups:bur group,200 mJ laser group,100 mJ laser group.The coronal pulp were removed by traditional bur or 200 mJ/20 Hz or 100 mJ/20 Hz Er:YAG laser.Then,they were dressed with mineral trioxide aggregate (MTA)and sealed with resin.Clinical,radiological and histological ana-lyses were performed 1 day,2 weeks,4 weeks and 8 weeks after treatment.The mobility and gingiva si-tuation were evaluated for clinical evaluation.Periapical films were used for radiological evaluation.The extracted teeth were preserved in 10% formalin.After decalcification,tissue processing,paraffin embed-ding,serial sectioning at 5 μm thickness,staining (Hematoxylin and Eosin,HE),the samples were as-sessed by an independent observer for calcified bridge formation and radicular pulp inflammation.The mean thickness of dental bridge was measured if there was complete dental bridge.Results:Clinical evaluation:there were no signs of fistula or mobility or any abnormal symptoms in Er:YAG laser groups and bur group during the observation period.Radiological evaluation:there were no signs of widened pe-riodontal ligament or root absorption or periapical radiolucency in Er:YAG laser groups and bur group. Histological evaluation:there was no severe inflammation reaction in 200 mJ/20 Hz,100 mJ/20 Hz Er:YAG laser groups and bur group 1 day,2 weeks,4 weeks,8 weeks post-operation in Hematoxylin and Eosin staining.A complete dentin bridge could be observed in 200 mJ/20 Hz,100 mJ/20 Hz Er:YAG laser groups,while no complete dentin bridge in bur group 2 weeks post-operation.Complete dental bridge could be observed in each group 4 and 8 weeks post-operation.The mean thickness of dental bridge 4 weeks post-operation in 200 mJ laser group was 77 μm,100 mJ laser group 87 μm,and bur group 101 μm,and 8 weeks post-operation in 200 mJ laser group was 222 μm,100 mJ laser group 160μm,and bur group 152 μm.Conclusion:The 200 mJ/20 Hz and 100 mJ/20 Hz Er:YAG laser pulpoto-mies show no harm to radicular pulp and can promote the formation of dentin bridge.关键词
牙髓切断术/Er:YAG 激光/牙本质/犬Key words
Pulpotomy/Er:YAG laser/Dentin/Dogs分类
医药卫生
