OBJECTIVE: The aim of this systematic review was to evaluate the effects of ultrasonic instrumentation and air polishing on surface roughness and marginal integrity of dental restorations, addressing their potential adverse impacts on various biomaterials. MATERIALS AND METHODS: A search of five databases, supplemented by manual searches, identified relevant laboratory studies. Forty-two studies met the inclusion criteria, with data on surface roughness and marginal quality extracted for analysis. The RoBDEMAT tool was used to assess risk of bias. RESULTS: Ultrasonic instrumentation significantly increased roughness, particularly in resin-modified glass ionomer cements and resin-based composites, whereas zirconia and lithium disilicate were less affected. Air polishing, especially with sodium bicarbonate and calcium carbonate powders, also increased roughness. Erythritol and glycine powders were the least abrasive. Both ultrasonic scaling and air polishing negatively impacted marginal quality. The RoBDEMAT assessments revealed shortcomings in randomization, sample size justification, and blinding. CONCLUSIONS: Ultrasonic instrumentation and air polishing can adversely affect dental restorations, with the degree of impact varying by biomaterial and debridement method. Low-abrasive powders, such as erythritol and glycine, are recommended. Methodological refinements and clinical studies are needed to enhance the applicability of these findings to patient care. CLINICAL SIGNIFICANCE: This review highlights the critical need to choose appropriate debridement methods to minimize iatrogenic damage to dental restorations. Low-abrasive air polishing powders, such as erythritol and glycine, are recommended for the removal of soft deposits and stains to preserve surface smoothness and marginal integrity.