Effect of intraoral administration of parathyroid hormone on osseous and soft tissue healing around implants in ovariectomized rat maxillae

• Published in: Clinical oral implants research Vol. 35; no. 3; pp. 305 - 320
• Main Authors: Al-Omari, Farah A, Kuroshima, Shinichiro, Uto, Yusuke, Uchida, Yusuke, Sawase, Takashi
• Format: Journal Article
• Language: English
• Published: Denmark Wiley Subscription Services, Inc 01-03-2024
• Subjects: Bone implants; Bone mass; Computed tomography; Connective tissues; Healing; Osteoclasts; Osteocytes; Osteoporosis; Ovariectomy; Parathyroid hormone; Soft tissues; SOST protein; Surgical implants; Tissues; Transplants & implants; tissue healing; parathyroid hormone; bone quality; osteoporosis; intraoral; implants
• ISSN: 0905-7161; 1600-0501
• DOI: 10.1111/clr.14227

Intermittent administration of parathyroid hormone (PTH) increases systemic bone mass. However, the effect of PTH on osseous and soft tissue healing around implants in osteoporosis patients remains unclear. This study aimed to investigate the effects of PTH on tissue healing around implants in ovariectomized rats and to compare systemic and intraoral administration routes.
Implants were placed at the healed sites of ovariectomized rats 3 weeks after maxillary first molar extraction. Rats were randomly divided into two groups that received either daily systemic subcutaneous or local intraoral PTH administration. Maxillae were dissected to examine bone architectures with micro-computed tomography images. Histomorphometric and immunohistochemical analyses were performed to evaluate osseous and soft tissue healing around the implants.
Regardless of the administration route, PTH significantly increased bone area and the numbers of osteoblasts, osteoclasts, and osteocytes in the first and second inside and outside areas of implant threads, in addition to decreasing the number of sclerostin
osteocytes. However, the intraoral PTH administration route was superior to the systemic route by significantly improving bone quality and promoting collagen production in the connective tissue around implants.
Parathyroid hormone administration promoted both osseous and soft tissue healing around implants, irrespective of administration route. Interestingly, intraoral administration improved the evaluated parameters more than systemic administration. Thus, the intraoral route could become a useful treatment strategy for implant treatment in osteoporosis patients.