Peri-implantitis is most frequently induced by poor oral hygiene or periodontitis/periapical periodontitis from adjacent teeth, rarely by infection from antagonist teeth. The present retrospective study reported a case of early-period im plant failure caused by antagonist teeth periodontitis. Clinical exam ination results and X-ray films were presented. Precaution, diagnosis and treatm ent of early-period peri-im plantitis were analyzed. Results indicated that pathological changes may be curbed or even reversed only if inflammation tissue and source of infection could be eliminated in time.
