Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
Division of Advanced Dental Devices and Therapeutics, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Int J Implant Dent. 2022 Mar 7;8(1):11. doi: 10.1186/s40729-022-00408-4.
Low bone quantity and quality are serious problems that affect the prognosis of implants in the cosmetic field. Therefore, artificial bone substitutes are frequently used. However, whether there is a difference in the effect of either bone substitute on soft tissue healing is unclear given their greatly different absorbability. In this study, we used hydroxyapatite (HAp) and carbonate apatite (COAp) as bone substitutes to analyze the epithelial and connective tissue healing after tooth extraction.
In vitro, oral mucosa-derived epithelial cells (OECs) collected from 4-day-old Wistar rats were seeded on HAp or COAp and evaluated for adhesion, proliferation, migration, apoptosis, and morphology. Fibroblasts (FBs) were also analyzed for their ability to express collagen. In vivo, the extraction of maxillary right first (M1) and second molars (M2) of 6-week-old male Wistar rats was performed, followed by insertion of HAp or COAp granules into the M1 and M2 sites. The oral mucosal healing process was then evaluated histochemically after 7 and 14 days.
In vitro, high collagen expression by FBs in the COAp group was observed and the surface analysis showed spreading of the FBs on the COAp surface. However, the activity of OECs was suppressed on COAp. Two weeks after COAp implantation, soft tissue healing was observed, and recovery of the connective tissue was observed on the remaining COAp.
Our results suggest that the formation of soft tissues, including connective tissue, was promoted by COAp in the extraction socket within a short period.
骨量和骨质量低是影响美容领域植入物预后的严重问题。因此，经常使用人工骨替代品。然而，鉴于它们的吸收率差异很大，不清楚哪种骨替代物对软组织愈合的效果更好。在这项研究中，我们使用羟基磷灰石（HAp）和碳酸磷灰石（COAp）作为骨替代物，分析拔牙后上皮和结缔组织的愈合情况。
在体外，从 4 天大的 Wistar 大鼠中收集口腔黏膜来源的上皮细胞（OECs），将其接种在 HAp 或 COAp 上，并评估其粘附、增殖、迁移、凋亡和形态。还分析了成纤维细胞（FB）表达胶原蛋白的能力。在体内，对 6 周龄雄性 Wistar 大鼠的上颌右侧第一（M1）和第二磨牙（M2）进行拔牙，然后将 HAp 或 COAp 颗粒插入 M1 和 M2 部位。然后在第 7 和 14 天通过组织化学评估口腔黏膜愈合过程。
在体外，COAp 组中 FB 表达出较高的胶原蛋白，表面分析显示 FB 在 COAp 表面扩散。然而，OECs 的活性受到 COAp 的抑制。COAp 植入两周后，观察到软组织愈合，在剩余的 COAp 上观察到结缔组织的恢复。
我们的结果表明，COAp 在短时间内促进了包括结缔组织在内的软组织的形成。
