Periodontitis (PD) is an inflammatory condition that affects 20%-50% of the total global population, with severe disease occurring in 9.8% of individuals. clinically characterized by clinical attachment loss (CAL) and bleeding on probing (BOP) accompanied by increased probing pocket depth (PPD) and/or gingival recession, it may end with tooth loss if left untreated. non-surgical periodontal treatment (NSPT) represents the first line of treatment and involves the physical debridement of subgingival plaque biofilms. "full-mouth debridement" (FMD) approach, its NSPT delivers complete debridement within 24 hr. However, full-mouth NSPT has been consistently shown to trigger a large systemic inflammatory response 24 hr following treatment. Nevertheless, Interestingly, a positive correlation between treatment time and the subsequent systemic inflammatory response has been reported. Given this previous link and the different features of each instrumentation technique including air-polishing devices (APDs), that have less time-consuming treatment, reduce patient discomfort and sensitivity, and only minor alterations to surrounding soft and hard tissues. This study aims to evaluate the systemic inflammatory response following full-mouth erythritol powder air polishing and instrumentation.

Periodontitis is a common chronic inflammatory disease caused by specific oral dysbiosis and characterized by a progressive loss of soft and hard tissues keeping the teeth. if left untreated, it leads not only to tooth loss, negative influences on the patient's quality of life and masticatory impairment may happen. There is significant evidence of clinical improvements in PD patients following non-surgical periodontal treatment (NSPT), including gains in clinical attachment level, reductions in gingival inflammation, and reduced periodontal pocket depths.

A conventional Full-mouth hand debridement has been consistently shown to trigger a large systemic inflammatory mediator, The reasons for such a response may be related to both the transient post-operative bacteremia and the extension of the operative trauma.

a recent joint consensus statement advised against full-mouth debridement for some medically compromised patients.

The erythritol powder is a water-soluble, non-toxic sugar alcohol and artificial sweetener, has a mean particle size of 14 μm, and can be used for supra and subgingival removal of biofilm and stains.

It has also been suggested that teeth with sites of furcation involvement and/or with reduced access, which have traditionally been difficult to debride with conventional instrumentation, may benefit from air-flow therapy

Comparing full-mouth ultrasonic debridement with polishing paste and full-mouth erythritol powder air polishing followed by ultrasonic debridement. this study hypothesized that the later procedure may reduce the extent of systemic inflammatory mediators they induce by removing the biofilm before the conventional full-mouth (supra and sub-gingival) ultrasonic debridement.

Inclusion Criteria:

• Participants who have periodontitis, unstable, at any stage

Exclusion Criteria:

• Participants who are known or suspected high risk for tuberculosis
• Participants who have hepatitis B or HIV infections
• Participants who are being unable to provide written, informed consent
• Participants who have history of bleeding diathesis
• Participants who are pregnant or intended to and lactating mother.
• Participants who are self-reported diagnosis of any systemic illnesses including cardiovascular, renal and liver diseases
• Participants who have regular use of medication to control systemic illness.