Implantology and Peri-Implant Disease
Implantology and Peri-Implant Disease
This domain tests surgical positioning, loading decisions, and the mucositis/peri-implantitis distinction with its 2018 case definitions.
Core rules
- Osseointegration: direct bone-to-implant contact without intervening soft tissue; primary stability is mechanical, secondary stability biologic (bone remodeling).
- Position: 1.5–2 mm from an adjacent tooth, about 3 mm between implants, roughly 3 mm buccal for the peri-implant supracrestal soft tissue; a buccal plate under 1.5 mm risks resorption.
- Peri-implant soft tissue has no cementum or PDL; supracrestal fibers run parallel, so the seal is weaker than around teeth.
- Peri-implant mucositis: BOP and/or suppuration with no bone loss beyond initial crestal remodeling - reversible. Peri-implantitis: bleeding plus progressive bone loss, with ≥3 mm loss and PD ≥6 mm as severity thresholds in the 2018 classification.
- Treatment: nonsurgical debridement for mucositis; peri-implantitis needs surgical access, decontamination, implantoplasty of exposed threads, and consideration of regenerative or resective approaches; explantation when mobile or non-restorable.
Worked example
A 6-year-old mandibular implant has 5 mm buccal PD, BOP, suppuration and 3.5 mm of bone loss compared with the 1-year radiograph. This is peri-implantitis, not mucositis. Nonsurgical debridement alone is insufficient; plan flap access with surface decontamination and reassess in 3 months.
Traps
Assuming probing around implants causes damage (probing is required for diagnosis); diagnosing peri-implantitis without a baseline radiograph; leaving excess cement in a cement-retained restoration; ignoring keratinized tissue and plaque control.