title: Management and prevention of retrograde peri-implant infection from retained root tips: two case reports.
abstract: Fracture of root tips in the maxillary premolar region is not an uncommon finding because of the high incidence of bifid and root dilacerations. Therefore, a retained root tip may serve as a nidus of infection when a dental implant is placed. The likely result is the development of an implant periapical lesion. This case report shows the successful management of a rapidly developing implant periapical lesion caused by an undetected retained root tip. Initially, systemic antibiotics failed to subdue the infection. A retained root fragment was retrieved surgically, together with the implant, and a new wide-body implant was engaged with DFDBA mixed with tetracycline. A 5-month follow-up showed increased radiographic density, and clinical reentry revealed the formation of bone with a hard consistency. The second case demonstrates the management of a retained root tip via a guided bone regeneration technique when it is detected prior to or during implant placement. Finally, a systematic therapeutic approach is proposed based on 17 case reports on implant periapical lesion management.
authors.affiliation: School of Dentistry, University of Michigan, Ann Arbor 48109-1078, USA.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Park
authors.forename: William P
authors.initials: WP
authors.lastname: Sorensen
authors.forename: Hom-Lay
authors.initials: HL
authors.lastname: Wang
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D001861:Bone Regeneration / Q000502:physiology; D016025:Bone Transplantation; D003751:Dental Fistula / Q000517:prevention & control / Q000628:therapy; D015921:Dental Implants; D005500:Follow-Up Studies; D048091:Guided Tissue Regeneration; D006801:Humans; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000517:prevention & control / Q000628:therapy; D010483:Periapical Diseases / Q000517:prevention & control / Q000628:therapy*; D013752:Tetracycline / Q000008:administration & dosage; D014082:Tooth Fractures / Q000150:complications* / Q000601:surgery; D014092:Tooth Root / Q000293:injuries* / Q000601:surgery
chemical_list: D000900:Anti-Bacterial Agents; D015921:Dental Implants; D013752:Tetracycline