Biological Basis of Periodontal Regeneration Decontamination and Biomodification of Periodontally Affected Root Surface for Successful Regeneration: Is There Room for Improvement? Inflammation and Periodontal Regeneration Stem Cell Applications in Periodontal Regeneration The Evolution of Surgical Techniques and Biomaterials for Periodontal Regeneration Soft Tissue Regeneration at Natural Teeth Regenerative Periodontal Therapy in Intrabony Defects and Long-Term Tooth Prognosis Scaffolds in Periodontal Regenerative Treatment Nanomedicine and Periodontal Regenerative Treatment Biomarkers and Periodontal Regenerative Approaches