Controlled Study Comparing REPaiR® and MIST Therapies for Treatment of Periodontitis

Inclusion Criteria: * Subjects 18 to 75 years of age, inclusive. * Subjects must be diagnosed with moderate to severe generalized periodontitis (ADA Classification Case Type III or IV) as determined by the investigator. * Subjects must have at least one, but up to 2, non-adjacent, qualifying Study Teeth with Pockets (PPD ≥ 6 mm \& intrabony vertical ≥ 3 mm, with base of defect ≥ 3 mm coronal to the tooth apex, and defect angle ≥ 25° as defined by radiograph) on non-adjacent teeth. * Subjects will have read, understood and signed an institutional review board (IRB) approved Informed Consent Form (ICF). * Subjects who are able and willing to adhere to the study visit schedule and other protocol requirements. Exclusion Criteria: * Visual inability to identify cementoenamel junction (CEJ) or other landmark for probing measures. * Presence of an acute periodontal abscess at the time of MIST or REPaiR treatment steps * Mobility \> 1 at the time of MIST or REPaiR treatment steps * Use of 3rd molars, defects distal to terminal 2nd molars, and teeth treated endodontically as study teeth. * Subjects with healing disorders (such as: diabetes mellitus confirmed HgA1C of \> 7 within 6-months of screening, cancer, HIV, bone metabolic diseases or Type IV heart disease) that could compromise wound healing and/ or preclude periodontal surgery; or who are taking medications that compromise wound healing, such as chronic steroid use - either inhaler or systemic, calcium channel blockers with clinical evidence of secondary hyperplastic tissue reactions, anti-seizure medications, medications for bone metabolic diseases, radiation or other immuno-suppressive therapy. * Traumatic occlusion of study teeth not addressed by occlusal adjustment or splint therapy during the course of the study prior to conclusion of SRP * Subjects taking intramuscular or intravenous bisphosphonates. * Subjects smoking \>10 cigarettes per day or an equivalent amount of any other nicotine products, such as smokeless chewing tobacco, nicotine patch, vaporizer, gum, pipe, or cigar smoking. * Female subjects who are pregnant or lactating, or who intend to become pregnant during the study duration. * Anticipated use of systemic antibiotics during the trial or within 30 days of SRP * An existing condition that may warrant use of antibiotics during the trial (e.g., ongoing infection noted at Screening Visit, cystic fibrosis or chronic obstructive pulmonary disorder with history of frequent, recurrent lung infections). Use within 30 days prior to Day 1, or a condition for which use is anticipated during trial: topical oral, nasal and systemic corticosteroids. * Anticipated use of the agents known to affect periodontal status during the trial and/or use within 30 days prior to Day 1: immunosuppressants, calcium antagonists or phenytoin- - Participation in another clinical study within 90 days prior to Day 1. * Subjects who received oral health treatments/interventions within 90 days of Day 1, which the investigator believes may interfere with the periodontal parameters to be assessed in this study (e.g., significant dental and/or gum/oral tissue work). * Untreated moderate to severe periodontitis. * Subjects, who in the opinion of the Investigator, for any reason other than those listed above, will not be able to complete the study per protocol