Friedman S, Rotstein I, Bab I
Department of Endodontics, Hebrew University, Hadassah Faculty of Dental Medicine, Jerusalem, Israel.
Lasers Surg Med. 1992;12(1):104-11. doi: 10.1002/lsm.1900120116.
The potential advantages of CO2 laser in apical surgery have not been established histologically. Therefore, the long-term effects of CO2 laser on the apical and periapical tissues were examined histologically in dogs 6 months after apical surgery. Lased specimens and unlased controls showed periapical inflammatory and osteogenic reactions. Lased root surfaces revealed craters with a superficial charred layer closely associated with new cementum-like matrix. The subjacent dentin appeared tubule-free and eosinophilic. Lased bone trabeculae showed a charred layer with a deeper osteocyte-free zone. The charred layer was covered by new bone. Detached charred segments in the marrow space and periapical inflammatory infiltrate were intimately associated with multinucleated giant cells, some containing minute char particles. Such cells were absent from the root and trabecular char linings. In addition, the charred surfaces were free of hard tissue resorption. These results suggest that CO2 laser does not hinder healing when applied in apical surgery.
二氧化碳激光在根尖手术中的潜在优势尚未通过组织学得到证实。因此，在犬根尖手术后6个月，对二氧化碳激光对根尖和根尖周组织的长期影响进行了组织学检查。激光照射组标本和未照射对照组均显示根尖周有炎症和成骨反应。激光照射的牙根表面可见伴有浅表烧焦层的凹坑，该烧焦层与新的类牙骨质基质紧密相连。其下方的牙本质呈无小管且嗜酸性。激光照射的骨小梁显示有烧焦层，其下方有较深的无骨细胞区。烧焦层被新骨覆盖。骨髓腔中的游离烧焦段和根尖周炎性浸润与多核巨细胞密切相关，一些多核巨细胞含有微小的炭粒。牙根和小梁烧焦层内未见此类细胞。此外，烧焦表面无硬组织吸收。这些结果表明，二氧化碳激光应用于根尖手术时并不妨碍愈合。
