Journal Article

Effectiveness and Safety of Mechanical Debridement for Treating Experimental Peri-Implantitis in Elderly Rats Receiving Oncological Dosages of Zoledronate

Freire, Jéssica de Oliveira Alvarenga, Costa, Leandro Lemes da, Ganzaroli, Vinícius Franzão, Casatti, Cláudio Aparecido, Pereira, Estevão Lopes, Mello-Neto, João Martins de, Machado, Beatriz Alexandrelli, Souza, Eduardo Quintão Manhanini, Cintra, Luciano Tavares Ângelo, Toro, Luan Felipe, Ervolino, Edilson, Garcia, Valdir Gouveia, Theodoro, Letícia Helena, Matsumoto, Mariza Akemi

2026

Overview

This study evaluated the effectiveness and safety of mechanical debridement (MD) in treating experimental peri-implantitis (EPI) in rats with osseointegrated implants, specifically those treated with high-dose zoledronate. Senescent Wistar rats underwent the extraction of their upper incisor, followed by immediate implant placement. After 8 weeks, the implants were exposed, and a transmucosal component was placed. The animals were divided into four groups: Control (C), ZOL, ZOL-EPI, and ZOL-EPI-MD. In the 9th week, drug treatment commenced, consisting of the administration of 0.45 mL of a vehicle (for group C) or zoledronate (for groups ZOL, ZOL-EPI, and ZOL-EPI-MD) every 4 days over 10 weeks. After 5 weeks of drug treatment, a cotton bandage was placed around the implants to induce EPI in the ZOL-EPI and ZOL-EPI-MD groups. In the ZOL-EPI-MD group, the ligature was removed at week 16, and local treatment was performed using MD. Euthanasia was conducted at week 19. Histological sections were obtained and stained with hematoxylin–eosin for histopathological and histometric analyses, such as the percentage of total bone tissue (B.Ar/T.Ar) and the percentage of non-vital bone tissue (NVB.Ar/B.Ar). Immunohistochemical reactions were performed to detect TNFα, IL-1β, VEGF, OCN, and TRAP. In the peri-implant connective tissue, mild, intense, and moderate inflammatory infiltrates were observed in the ZOL, ZOL-EPI, and ZOL-EPI-MD groups, respectively. Immunolabeling for TNFα and IL-1β correlated with these histopathological findings. The ZOL and ZOL-EPI-MD groups showed lower immunolabeling for VEGF compared to the control group. There was a reduction in TRAP-positive cells and lower immunolabeling for OCN in the groups treated with zoledronate, with the ZOL-EPI-MD group displaying even lower levels of OCN compared to the ZOL group. While there was no significant difference in B.Ar/T.Ar across the groups, both the ZOL, ZOL-EPI, and ZOL-EPI-MD groups exhibited higher levels of NVB.Ar/B.Ar, with the ZOL-EPI-MD group showing the highest NVB.Ar/B.Ar compared to ZOL and the other groups. In conclusion, MD, as a standalone treatment, showed neither effectiveness nor safety in the management of EPI in rats that received high doses of zoledronate.

• Publisher: MDPI AG,Multidisciplinary Digital Publishing Institute (MDPI)
• Subject: Animals / Biofilms / Bone Density Conservation Agents / Bones / Connective tissue / Debridement / Debridement - methods / Disease Models, Animal / Drug dosages / Edema / Fractures / Interleukin-1beta - metabolism / Male / Peri-Implantitis - drug therapy / Peri-Implantitis - etiology / Peri-Implantitis - pathology / Peri-Implantitis - therapy / Rats / Rats, Wistar / Transplants & implants / Vascular Endothelial Growth Factor A - metabolism / Zoledronic Acid - administration & dosage / Zoledronic Acid - adverse effects / Zoledronic Acid - pharmacology / Zoledronic Acid - therapeutic use