Aseptic Ligatures Induce Marginal Peri-Implant Bone Loss-An 8-Week Trial in Rabbits

Area of Science:

• Biomaterials Science
• Immunology
• Dental Implantology

Background:

• Clinical peri-implantitis models using ligatures are questioned due to artificiality.
• Previous studies lacked investigation into tissue reactions to common ligature materials like silk and cotton.

Purpose of the Study:

• To investigate hard and soft tissue reactions to silk and cotton ligature materials in a rabbit dental implant model.
• To evaluate the role of ligature materials in peri-implant bone resorption independent of plaque.

Main Methods:

• Dental implants were placed in rabbit femurs and tibias.
• Implants were ligated with silk or cotton, or left as non-ligated controls.
• Histological analysis and quantitative polymerase chain reaction (qPCR) were used to assess tissue reactions and immune response.

Main Results:

• Silk ligatures showed increased distance to first bone contact compared to controls.
• Both silk and cotton ligatures induced soft tissue encapsulation and bone resorption.
• qPCR confirmed an upregulated immune response to silk ligatures.

Conclusions:

• Silk and cotton ligatures provoke foreign body reactions, including soft tissue encapsulation and bone resorption around implants.
• These reactions occur independently of plaque accumulation.
• Ligature materials themselves can initiate inflammatory processes relevant to peri-implantitis.