The purpose of this observational research study is to understand more about wound healing of gum tissue. This study was the biomarker study of a small cohort of study participants derived from NCT01547962 (completed). Two surgical sites of each patient were randomly selected to receive CelTx™ as a donor material in one site and conventional autograft using keratinized tissue from the palate as the donor material at the contralateral (opposite side) site. Fluids collected from between a tooth and the gum and directly from wounds contain proteins that occur in different levels as the wound healing process proceeds. In this research study wound fluid will be collected from the donor palate site (roof of your mouth) and the treated sites on your gum before and after placement of CelTx and conventional treatment (tissue from the roof of your mouth) to measure which proteins and how much of each are present during the first 4 weeks of wound healing.

In a clinical trial designed to evaluate the safety and effectiveness of rhPDGF-BB to promote soft and hard tissue engineering of the periodontium, the subjects provided gingival crevicular fluid (GCF) or periodontal wound fluid (WF) and the results demonstrated contrasting inducible expression patterns of PDGF-AB, VEGF, and ICTP during periodontal healing [17, 24, 25]. However, little is known regarding the release of these molecules into local periodontal wound fluid during tissue-engineered grafts.

The aim of this study is to determine the presence and influence of angiogenic biomarkers, such as PDGF, VEGF, and FGF, involved in the wound healing process of tissue engineered grafts in the treatment of subjects (with recession-type defects) who have an insufficient zone of attached gingival associated with at least two nonadjacent teeth.

STUDY OBJECTIVES The purpose of this pilot study is to compare the expression of angiogenic biomarkers involved in the wound healing process of 2 different periodontal surgical approaches: 1) CelTx™ (living bilayered cell therapy product) and 2) free gingival grafts

Inclusion Criteria:

• Subject has signed informed consent to participate in Organogenesis Clinical Protocol 06-PER-002-CTX.
• Subject has signed informed consent to participate in this adjunct bio-marker study.
• Subject is willing to comply with the additional study visits at weeks 2 and 3 as required by this study.

Exclusion Criteria:

- Subject requires antibiotic prophylaxis for routine dental procedures.

6 months

No adverse or serious adverse events were observed.

Although the present study compared the differences in angiogenic biomarker expression between LCC and autograft, it is important to understand that both LCC and autograft heal by two different healing processes.