The purpose of this prospective, double-blinded, randomized, split-mouth study is to compare the effectiveness of a porcine collagen matrix (CM) and coronally advanced flap (CAF) with or without the addition of enamel matrix derivative (EMD) in the treatment of Miller Class I, II, or predictable class III recession defects. One defect will receive CM + CAF + EMD (Experimental), while the other will receive CM + CAF (Control) alone. The treatment of 60 similarly sized Miller class I, II, or predictable class III recession defects on single-rooted teeth in 30 subjects using CM + CAF + EMD or CM + CAF alone will be evaluated. The subjects will be in good health, non-smokers, periodontally healthy with good oral hygiene and have no contraindications to periodontal surgery. Paired, similar sized defects on single-rooted teeth will be in the same subject and measure within 2mm of each other. One defect will be randomly assigned as the test group using CM + CAF + EMD, and the other as the control group using only CM + CAF. Clinical measurements will be made using a UNC-15 periodontal probe by calibrated, board certified periodontists and will include: probing depth (PD), clinical attachment level (CAL), vertical recession (RD), and width of keratinized tissue (KT). Percent root coverage (%RC) will be calculated. The measurements will be used to evaluate surgical outcome. Surgical outcome will also be assessed using stone models. All measurements will be taken at baseline (on the day of the surgery) and 3 and 6 months post-surgery for comparison.

Inclusion Criteria:

• Age 18 years or over
• Patient will remain in the Capital region for at least 6 months following the surgical procedure for follow up appointments
• Patient must be otherwise periodontally healthy
• Patient must be systemically healthy (ASA class I or II)
• Patient must have no contraindications to periodontal surgery
• Patient must have demonstrated good oral hygiene (plaque index <1 according to Silness and Löe)
• Paired Miller Class I, II or predictable III recession defects
• Bilateral, facial defects on single-rooted teeth

Exclusion Criteria:

• Self-reported history of smoking within previous 6 months
• Does not meet any of the preceding criteria
• Female patients who are pregnant or nursing
• Antibiotic medications taken within the last 6 months
• History of mucogingival surgery at the sites of interest
• Poor plaque control (>25% of sites)
• Those with clinically significant systemic disease, which may affect healing (i.e. uncontrolled diabetes or bone metabolic disease)
• Allergy to chlorhexidine gluconate (Peridex)
• Does not sign study consent or HIPAA forms
• Bleeding complications (e.g. hemophilia)
• Warfarin therapy
• History of osteoporosis or taking bisphosphonate medications
• History of radiation therapy in the head and neck area
• Mobile teeth beyond physiologic mobility
• Facial restorations at the site to be treated
• Recession defects that will require more than one 15x20mm Mucograft (per side)

Participants must meet health eligibility requirements and not have any conditions that will exclude them from the study (see exclusion criteria below). Females of reproductive age will be asked to submit urine samples for pregnancy testing prior to surgery. Urine HCG tests will be conducted in the Department of Periodontics in accordance with WRNNMC Bethesda Point of Care Testing Procedures. Pregnant females will be excluded from this study in accordance with standard of care (periodontal surgery is routinely deferred during pregnancy).