Aim: The occurrence of peri-implantitis was observed with the beginning of the placement of the first dental implants. With the increase in the number of dental implants, the frequency of complications in clinical practice, in the form of peri-implant diseases, has also increased. Antimicrobial photodynamic therapy (PDT) was introduced as a potential periimplantitis treatment option. The aim of the study was to determine the effect of the new antimicrobial photodynamic therapy (PDT) with the novel diode laser light (SiroLase Blue; Dentsply Sirona; Germany) of 445 nm wavelength in combination with the 0.1% riboflavin solution as a photosensitizing agent on the Staphylococcus aureus and Candida albicans biofilm on the surface of dental implants, and compare it with the effect of PDT with methylene blue 0.1% photosensitizing agent activated by diode laser with a wavelength of 660 nm and the effect of the often used 0.2% chlorhexidine solution. Methods: In the study 80 dental implants contaminated with Staphylococcus aureus and Candida albicans biofilm was used, randomly divided into 4 groups of 20 implants in each one. The implants were removed from the bacterial–fungal suspension using a sterile forceps, gently dried with sterile gauze to remove the excess bacterial and fungal solution and placed on sterile silicone holders. The negative control group (NC) was left without surface treatment. The positive control group (PC) was treated with a sterile cotton pellet soaked in a 0.2% chlorhexidine-based solution for 60 s using a brushing movement. The examined group was treated with 0.1% riboflavin dye and then radiated with a diode laser at 445 nm (Q power = 100 mW) in the pulsed mode of 100 Hz using an EasyTip 320 µm, with the max power density of 124.34 W/cm2 and energy density of 1.24 J/cm2, for 60 s moving in circles at approximately 1 mm from the implant surface. The second PDT group (PDT2) was treated using a similar procedure, with 0.1% methylene blue as a photosensitizing agent activated by a diode laser with a wavelength of 660 nm (Q power = 100 mW), in continuous-wave mode using an EasyTip 320 µm, with the max power density of 124.34 W/cm2 and max energy density of 1240 J/cm2, for 60 s moving in circles at approximately 1 mm from the implant surface. Results: PDT1 and PDT2 group showed greater reduction of Staphylococcus aureus and Candida albicans compared to NC group, and no significant difference compared to PC group. PDT1 and PDT2 groups compared showed no significant difference in disinfection of Staphylococcus aureus and Candida albicans microorganisms’ biofilm on dental implant surface. Conclusions: Analyzing the obtained results, it was determined that the new photodynamic protocol for disinfection of the implant surface with a diode laser of wavelength 445 nm and a 0.1% riboflavin solution is comparable to the existing protocols for disinfection of the implant surface with a solution of 0.2% chlorhexidine, as well as with a diode laser of wavelength 660 nm and 0, 1% methylene blue solution. It was concluded that the investigated protocol can lay the foundation for further clinical research and the beginning of use of a new wavelength of the blue light spectrum in combination with a new photosensitizing agent in clinical practice.