Preventing peri-implantitis with Ag-Est816 nanocomposite: modified rat model and preventive assessment.

BACKGROUND

Peri-implantitis is a prevalent complication leading to progressive bone loss around dental implants, with current therapeutic strategies offering limited preventive efficacy.

OBJECTIVE

This study aimed to develop a modified rat model of peri-implantitis to evaluate the effects of a silver nanoparticle and quorum quenching enzyme nanocomposite (Ag-Est816) on peri-implant bone health.

METHODS

The research comprised two parts: (A) development of the peri-implantitis rat model, and (B) assessment of Ag-Est816's preventive effect. In Part A, titanium implants infected with Porphyromonas gingivalis and Streptococcus sanguinis were surgically placed into the femurs of five male Sprague-Dawley rats weighing 180-220 g. After four weeks, peri-implant bone loss was evaluated using micro-computed tomography (Micro-CT) to measure bone volume to total volume ratio (BV/TV), and histological analysis was performed to assess bone architecture. Non-infected implants served as controls. In Part B, Ag-Est816 was applied to infected titanium implants, while control implants were treated with sterilized phosphate-buffered saline (PBS). Micro-CT and histological analysis were used to evaluate bone loss and tissue integrity.

RESULTS

In Part A, the BV/TV of infected implants and controls was 6.9 ± 1.4% vs. 32.8 ± 9.0% (p < 0.001). Histological analysis revealed disorganized collagen, impaired mineralization, and stalled bone formation at the implant interface in the infected samples, in contrast to the ordered, mature osseointegration observed in the controls. In Part B, the BV/TV of Ag-Est816-treated implants and controls was 23.6 ± 3.3% vs. 5.1 ± 1.8% (p < 0.001). Histological analysis revealed new bone regeneration with trabecular integrity around Ag-Est816-treated implants, in contrast to compromised osseointegration with disrupted, sparse bone and fibrous, inflammatory tissue in the controls.

CONCLUSIONS

A modified rat femur model of peri-implantitis was successfully developed. Ag-Est816 effectively prevented peri-implant bone loss.