DENTAL IMPLANTS IN IRRADIATED JAWS: OSSEOINTEGRATION, OSTEORADIONECROSIS, AND CLINICAL DECISION-MAKING

Abstract

Radiotherapy for head and neck tumors may produce persistent changes in oral and maxillofacial tissues, including vascular impairment, fibrosis, and alterations in bone metabolism and remodeling. These changes represent important challenges for dental implant rehabilitation, particularly because of their potential effects on osseointegration and the risk of osteoradionecrosis. Although radiotherapy has historically been considered a major risk factor for implant therapy, recent evidence indicates that implant-supported rehabilitation may be feasible in carefully selected patients. Quantitative syntheses indicate that implant survival is generally lower in irradiated than non-irradiated bone; one meta-analysis reported 91.9% survival after radiotherapy versus 97% in non-irradiated patients, while osteoradionecrosis occurred in approximately 3% of irradiated patients. This narrative review aimed to examine the current evidence regarding dental implants in irradiated jaws, with emphasis on radiation-induced biological changes, osseointegration, implant survival, osteoradionecrosis, radiation dose, anatomical considerations, timing of implant placement, and clinical decision-making. A non-systematic literature search was conducted in PubMed/MEDLINE, Scopus, and Web of Science, prioritizing clinical guidelines, systematic reviews, meta-analyses, umbrella reviews, and relevant clinical studies. The findings indicate that radiotherapy should not be considered an absolute contraindication to implant therapy; however, clinical outcomes are heterogeneous and depend on patient-related factors, radiation exposure, and characteristics of the surgical site. Currently, no universally applicable radiation-dose threshold or waiting period can independently determine the safety of implant placement. Therefore, treatment planning should consider the dose delivered to the specific implant site, local tissue conditions, anatomical location, oncological status, and the expected functional benefits of rehabilitation. In conclusion, implant therapy in irradiated jaws requires an individualized, site-specific, and multidisciplinary approach in which the benefits of rehabilitation are carefully balanced against biological and surgical risks.