What is the most common RESTORATIVE-related cause of peri-implant inflammation?

Correct answer: D. Residual excess cement in the peri-implant sulcus

• A. An over-contoured emergence profile does impede hygiene access and contributes to inflammation, but it is a secondary factor compared with retained cement.
• B. Occlusal overload is associated with MECHANICAL complications — screw loosening, screw or abutment fracture, porcelain chipping and, in some analyses, marginal bone loss — but it is not the primary driver of peri-implant INFLAMMATION, which is biofilm-mediated.
• C. An open contact causes food impaction and local inflammation and is a real problem, but it is far less common than cement retention as a cause of peri-implant disease.
• D. CORRECT. RESIDUAL EXCESS CEMENT is the leading restorative cause of peri-implant mucositis and peri-implantitis. Cement extruded into the peri-implant sulcus during seating is very difficult to detect and remove: unlike a natural tooth, the implant has no periodontal ligament and no supracrestal connective tissue attachment perpendicular to the surface, so cement migrates apically with ease. It is often radiographically invisible if radiolucent, and it acts as a persistent foreign body colonised by biofilm. Studies have found excess cement in the large majority of implants with peri-implant disease, with resolution in most cases after its removal.

Note: Prevention strategies: keep the crown margin at or above the mucosal level (ideally no more than 1-1.5 mm subgingival), use a minimal amount of cement, seat the crown on a duplicate abutment or a vented custom device to extrude excess cement extraorally before seating, or avoid the problem entirely by choosing a SCREW-RETAINED design where implant angulation permits.