Peri-Implantitis/therapy; Anti-Infective Agents, Local/therapeutic use; Bacteroides/isolation & purification; Chlorhexidine/analogs & derivatives; Chlorhexidine/therapeutic use; Clinical Protocols; Dental Scaling/methods; Female; Follow-Up Studies; Fusobacterium nucleatum/isolation & purification; Gingival Crevicular Fluid/enzymology; Gingival Recession/microbiology; Gingival Recession/surgery; Gingival Recession/therapy; Humans; Low-Level Light Therapy/methods; Male; Matrix Metalloproteinase 8/analysis; Middle Aged; Peri-Implantitis/microbiology; Peri-Implantitis/surgery; Periodontal Attachment Loss/microbiology; Periodontal Attachment Loss/surgery; Periodontal Attachment Loss/therapy; Periodontal Index; Periodontal Pocket/microbiology; Periodontal Pocket/surgery; Periodontal Pocket/therapy; Photochemotherapy/methods; Porphyromonas gingivalis/isolation & purification; Prospective Studies; Root Planing/methods; Suppuration; Surgical Flaps/surgery; Treatment Outcome; Treponema denticola/isolation & purification