A novel technique to harvest bone autografts with mild local hyperthermia and enhanced osteogenic bone quality: a preclinical study in dogs

Tengfei Zhou; Zekun Gan; Hanfei Zhang; Ziyi Liu; Yiping Pu; Mingdeng Rong

doi:10.1186/s12903-023-03611-w

A novel technique to harvest bone autografts with mild local hyperthermia and enhanced osteogenic bone quality: a preclinical study in dogs

BMC Oral Health. 2023 Nov 7;23(1):838. doi: 10.1186/s12903-023-03611-w.

Authors

Tengfei Zhou¹, Zekun Gan¹, Hanfei Zhang², Ziyi Liu², Yiping Pu³, Mingdeng Rong⁴

Affiliations

¹ Department of Periodontology and Oral Implantology, Stomatological Hospital, Southern Medical University, Guangzhou, 510280, China.
² Stomatological Hospital, Southern Medical University, Guangzhou, 510280, China.
³ Department of Oral Surgery, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200001, China. yvettepeen@126.com.
⁴ Department of Periodontology and Oral Implantology, Stomatological Hospital, Southern Medical University, Guangzhou, 510280, China. rmdeng@smu.edu.cn.

Abstract

Background: Guided bone regeneration (GBR) involves collecting bone autografts with high bio-quality and efficiency. The current non-irrigated low-speed drilling has been limited for broader application in bone autograft harvest due to its low efficiency, inability to conduct buccal cortical perforation, and dependence on simultaneous implant placement. Increasing the drilling speed helps improve the efficiency but may incur thermal-mechanical bone damage. Most studies have addressed thermal reactions during bone drilling on non-vital models, which is irrelevant to clinical scenarios. Little has been known about bone's in vivo thermal profiles under non-irrigated higher-speed drilling and its influences on the resulting bone chips.

Aim: A novel technique for bone harvest and cortical perforation via in-situ non-irrigated higher-speed drilling was proposed and investigated for the first time.

Methods: The third mandible premolars of eight beagles were extracted and healed for three months. Sixteen partial edentulous sites (left and right) were randomized into four groups for bone autograft harvest without irrigation: chisel, 50 rpm drilling, 500 rpm drilling, and 1000 rpm drilling. Bone chips were harvested on the buccal plates of the missing tooth. An infrared camera and an implantable thermocouple collaboratively monitored in vivo real-time bone temperature at the drilling sites. In vitro performances of cells from bone chips, including cell number, viability, proliferation, migration, ALP activity, in vitro mineralization, mRNA transcriptional level of osteogenic genes and heat shock protein 70 (HSP-70), and HSP-70 expression at the protein level were also studied.

Results: 500 rpm produced mild local hyperthermia with a 2-6 °C temperature rise both on the cortical surface and inside the cortical bone. It also held comparable or enhanced cell performances such as cell number, viability, proliferation, migration, ALP activity, in vitro mineralization, and osteogenic genes expression.

Conclusions: In-situ non-irrigated higher-speed drilling at 500 rpm using a screw drill is versatile, efficient, and thermal friendly and improves the bio-quality of bone chips. Our novel technique holds clinical translational potential in GBR application.

Keywords: Bone autografts; Bone drilling; Bone temperature; Guided bone regeneration; Osteotomy; Thermal exposure.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Autografts
Bone and Bones
Dogs
Hot Temperature
Hyperthermia, Induced*
Osteogenesis
Osteotomy* / methods