OBJECTIVE: To identify which methods have been used to deliver adjunctive probiotics during the non-surgical management of periodontitis in clinical trials. This review also investigates which probiotics have been used and at what dose, along with the periodontal treatment outcomes achieved. DATA: Conducted in accordance with the Joanna Briggs Institute methodology for scoping reviews. SOURCES: MEDLINE, Embase, Web of Science, and Scopus were searched on 02/02/2024 from inception with no date limits applied. STUDY SELECTION: Clinical trials investigating the use of probiotics as an adjunctive treatment to non-surgical periodontal therapy in humans. CONCLUSIONS: Out of 4769 studies 66 met the inclusion criteria. Over 30 different probiotics were identified along with 18 different delivery methods with varying dosages and duration. 48 of the included studies reported a beneficial effect when a probiotic was used, 14 reported no difference, 3 found the outcomes comparable to the use of antibiotics, and 1 study reported a better outcome from the control group. The probiotic used, its dosage, delivery method, duration of application, and outcome measures differ across studies making it difficult to draw conclusions on their efficacy. This scoping review highlights the need for further research to establish a uniform treatment protocol and to identify the most effective probiotic bacteria. CLINICAL SIGNIFICANCE: Despite the majority of included studies indicating a potential benefit from the use of probiotics during the non-surgical management of periodontitis, the high level of heterogeneity between interventions they currently cannot be recommended for use in clinical practice.