RESUMEN
This study identified the scientific literature comparing the influence of different times in which dental procedures were performed before the oncological treatments (radiotherapy and/or chemotherapy) on the risk of oral complications development. MEDLINE/PubMed and Embase databases were searched, and articles were selected by title, abstract and full-text assessment. The search identified 2,356 articles and three retrospective observational studies were included. Data were collected and analyzed according to the dental procedure, the time before oncological treatment, and oral complications. Risk of bias (ROBINS) and certainty of evidence (GRADE) were evaluated. Pairwise meta-analyses were performed from dental extractions (Exo) data according to the time which were performed and ORN development using a random-effect model (RR and 95 % CI, p < 0.05). meta-analyses showed a higher risk of ORN development in patients with Exo performed < 2 weeks before oncological treatment than in those who Exo was performed > 2 weeks ≤ 1 month before oncological therapy (RR 1.29; 95 % CI 1.12-1.48; p < 0.01). There was a higher prevalence of oral mucositis (OM) in patients who received periodontal treatment ≤ 3 weeks before oncological therapy than those who received dental procedures > 3 weeks ≤ 6 months before. Although the risk of bias ranged from serious to critical, with very low certainty of evidence, the findings suggest that dental extractions should be performed within > 2 weeks before oncological treatment to avoid ORN complications. More studies are needed to conclude the appropriate time to perform dental procedures to decrease other associated oral complications. (CRD42021272652).