The Efficacy of Three Combinatory Decontamination Protocols and BMP-2-Incorporated BioCaP-Based Regenerative Material...

To screen decontamination efficacy of three combinatory protocols and to evaluate the regenerative efficacy of bone morphogenetic protein 2-incorporated biomimetic calcium phosphate granules (BMP2-inc. BioCaP) in treating implants with peri-implantitis.

Peri-implantitis model was established on 24 dental implants in 6 beagle dogs. The implants were decontaminated using mechanical curettage (MC) with either Chlorhexidine (CHX), photodynamic therapy (PDT), or both. The decontamination efficacy was assessed by measuring modified Sulcus Bleeding Index (mSBI), probing pocket depth (PPD), peri-implant sulcular fluid (PISF), and inflammatory cytokines of crevicular fluid (IL-8, IL-1β). Thereafter, GBR surgery was performed either without (Control) or with deproteinized bovine bone mineral (DBBM) or with BMP2-inc. BioCaP. Three fluoresceins were consequentially injected to assess bone growth rates. Eight weeks post-surgery, samples were subjected to micro-CT, confocal laser scanning microscopy and histomorphometric analyses.

MC + CHX + PDT was associated with the lowest levels of mSBI, PPD, PISF, IL-1β, and IL-8 2 weeks post decontamination. Eight weeks post GBR surgery, BMP2-inc. BioCaP yielded significantly higher bone volume fraction, trabecular thickness, trabecular number, bone mineral density, and significantly lower trabecular separation than DBBM and Control. BMP2-inc. BioCaP bore significantly higher total fluorescence intensities than DBBM and Control at 2, 4, and 6 weeks, and was also associated with significantly higher bone-to-implant contact and new bone height than DBBM and Control.

Within the limitations of this study, MC + CHX + PDT decontamination and BMP-2-incorporated BioCaP showed an application potential in treating peri-implantitis. Further studies with a long monitoring span are necessary before clinical application.