Gingival Recession Localized Moderate

This single-center prospective clinical study investigates how smoking affects palatal donor site tissue biology and, in turn, the success of connective tissue grafts used in root coverage surgery. A total of 24 systemically healthy patients with Cairo Type 1 (RT1) gingival recession will be enrolled: 12 smokers and 12 non-smokers. All participants will receive a coronally advanced flap combined with a subepithelial connective tissue graft (CAF + CTG) harvested from the palatal donor site. Both donor and recipient sites will be assessed at baseline and postoperatively (2 weeks, 1 month, and 3 months) using ultra-high frequency ultrasonography (UHFUS) to measure tissue thickness, echogenicity, structural integrity, and vascularization. Residual connective tissue fragments obtained during routine graft preparation will undergo histological, histochemical, and immunohistochemical analysis (including COL1A1, COL1A2, COL3A1, α-SMA, CD31, Factor XIIIa, and IL-33). Smoking status will be biochemically confirmed via salivary cotinine ELISA. Clinical outcomes (recession depth, clinical attachment level, keratinized tissue height, percentage of root coverage) and patient-reported outcome measures (PROMs) will be compared between groups. Primary Hypothesis: Smoking negatively affects palatal donor site biology, impairing the clinical and ultrasonographic healing outcomes of CAF + CTG procedures.

Participant in this study are asked to participate because they have teeth or dental implants that were identified as having very little gum tissue and would benefit from gum tissue graft surgery. This study has 2 treatment groups that differ only in the material that will be used at the graft site: * Gum tissue taken from the patient's own palate * Commercially available collagen matrix derived from porcine (pig) Achilles tendon (FDA-approved for the surgery done in this study). Both materials have been in use in dental practices for many years, but no studies have directly compared the outcomes between palatal tissue and the porcine collagen matrix we will use in this study. Participants will be randomized into one of the 2 groups using sealed envelopes (the process is like flipping a coin). All the study visits will take place during regular dental appointments that would be scheduled even if not participating in this research.

Multiple techniques can be used for recession coverage. The most common techniques for single recessions are : tunnel technique (T) and coronally advanced flap (CAF) both combined with a palatal graft to provide sufficient gingival thickness. Recently two modifications have been described in literature, namely the tunneled coronally advanced flap and the modified tunnel. MTUN will function as the control group while people treated with the TCAF technique will function as the test group. This randomized controlled trial compares MTUN and TCAF to determine which technique provides better root coverage for receding gums at single recession in the premandible. The main question it aims to answer is: \- What is the average root coverage achieved with each technique in the short and long term? This may be clinically relevant because covering gum recession can reduce tooth sensitivity, improve aesthetics and make oral hygiene easier. Researchers will compare the modified tunnel technique (MTUN = the gum is undermined) with the tunneled coronally advanced flap (TCAF = the gum is undermined, only partially detached and repositioned higher). In both techniques, a small piece of tissue is removed from the palate, which is used to cover the recession. The purpose of the connective tissue graft under the flap/tunnel, is to increase thickness and provide support. Pain associated to the material used to cover the donorsite will be seen as the secondary research question. The site will either be covered by spongostan and multiple stitches or a palatal stent. Participants will: * Undergo surgery (MTUN or TCAF, randomly assigned) to cover recessions * Attend regular check-ups for up to 10 years after surgery * Keep a postoperative journal (recording medication use, pain levels, tooth sensitivity, etc.)

Multiple techniques can be used for recession coverage. The most common techniques are: tunnel technique (T), coronally advanced flap (CAF) or a combination of both (TCAF). Tunnel and coronally advanced flap are frequently used in clinical practice, whereas the combined technique is a relatively recently developed surgical approach. This randomized controlled trial compares CAF and TCAF to determine which technique provides better root coverage for receding gums at multiple adjacent teeth in the upper jaw. The main question it aims to answer is: \- What is the average root coverage achieved with each technique in the short and long term? This may be clinically relevant because covering gum recession can reduce tooth sensitivity, improve aesthetics and make oral hygiene easier. Researchers will compare the coronally advanced flap (CAF = the gum is detached and repositioned higher) with the tunneled coronally advanced flap (TCAF = the gum is undermined, only partially detached and repositioned higher). In both techniques, a small piece of tissue is removed from the palate, which is used to cover the recession. The purpose of the connective tissue graft under the flap/tunnel is to increase thickness and provide support. Participants will: * Undergo surgery (CAF or TCAF, randomly assigned) to cover recessions * Attend regular check-ups for up to 10 years after surgery * Keep a postoperative journal (recording medication use, pain levels, tooth sensitivity, etc.)