Periodontitis is an infection of the ligament and bone supporting the tooth and is caused by the presence of periodontopathogenic species in a susceptible host, affecting 5% to 20% of the adult population in a clinically significant manner. Periodontal therapy is based on supra- and sub-gingival disinfection concomitant with the establishment of an environment that is less favorable for periodontopathogenic growth. Though the adequacy of mechanical debridement (scaling and root planing) in the treatment of periodontitis has been well acknowledged. Chemo-mechanical concept has been developed where in a chemical agent is used as an adjunct to scaling and root planing to improve the outcome of scaling and root planing and furthermore prevent early microbial re-colonization to ultimately ensure the best chance to clinical improvement. Therefore a research project was undertaken to evaluate the efficacy of Chlorhexidine - Thymol varnish (chemical) as an adjunct to scaling and root planing (mechanical) and compare it's results with mechanical debridement alone in the eradication of microbial colonies and improvement of periodontal parameters, which is discussed in depth in this book.

Periodontics is a dental specialty that encompasses the prevention, diagnosis and treatment of diseases affecting the supporting and surrounding tissues of the teeth (ie: periodontal tissues) or their substitutes, such as dental implants (ie: peri-implant tissues) and is also concerned with the maintenance of the health, function and aesthetics of these structures and tissues. Periodontal diseases are multifactorial infectious diseases wherein the presence of periodontopathogenic species seems to play a key role in the etiopathogenesis and results in a progressive loss of the hard and soft tissue around the teeth; which if left untreated, ultimately leads to the loosening and subsequent loss of teeth. Similarly diseases affecting peri-implant tissues, if not managed and treated properly results in an implant failure. However, the nature and severity of periodontal and peri-implant diseases depend on the patient's oral hygiene, interaction between the bacterial agent, the environment and the host defence mechanisms, and the presence of various risk elements for periodontal/peri-implant diseases like genetic factors, diabetes, smoking, etc. Periodontal disease itself can also act as a potential risk factor for several systemic conditions and may significantly enhance the probability for certain systemic diseases or alter their natural course. Fortunately, periodontal and peri-implant diseases are largely preventable and treatable conditions; and their successful long-term management and treatment requires a treatment strategy that integrates non-surgical, surgical and supportive periodontal/peri-implant therapy along with patient motivation and reinforcement of excellent oral hygiene measures.