the main goal of this clinical trial is to test the efficacy of amnion Chorion allograft in managing gingival recession. The main questions it aims to answer are: Is it effective in treating gingival recession, and how it compares to connective tissue graft.

Gingival recession (GR) is characterized by apical migration of soft tissue margin beyond the cemento-enamel junction (CEJ) or the platform of an implant.

Gingival recession is a common daily finding in every practice. As patients are more concerned with a pleasing smile, root exposure is a growing concern . Moreover, discomfort and inability to perform oral hygiene result from exposed root hypersensitivity. It affects the patient's abilities to maintain adequate plaque control which eventually complicates the situation more. It is advisable to augment tissues and increase keratinized tissue (KT) band to reduce discomfort and obtain an aesthetic smile.

multiple treatment modalities are available for treating gingival recession such as Pedicle flaps (coronally advanced flap (CAF), semilunar flap, laterally sliding flap (lSD), and double papilla flap), Free gingival graft (FGG), Subepithelial connective tissue graft (SCTG), Guided tissue regeneration. Modified coronally advanced tunnel, Vestibular incision subperiosteal tunnel access (VISTA), Pinhole technique (PST).

Size and number of recession defects, KT band, interproximal attachment level, depth vestibule and frenum pull are among factors to determine which procedure is suitable for that type of recession.

For single-type recession (localized or isolated), the use of CAF with SCTG is favorable for both root coverage and KT gain. According to the American Academy of Periodontology regeneration workshop "for Miller class 1 and 2 single-tooth recession defects, SCTG procedures provide the best outcome ". Using CAF combined with SCTG is considered the gold standard treatment for localized recession defects. SCTG improves root coverage, KT gain, and clinical attachment levels. Using SCTG helps stabilize CAF, increase root coverage predictability, and increase soft tissue thickness. CAF with SCTG is a predictable technique to increase root coverage, decrease recession depth, and increase KT width and thickness.

However, obtaining an SCTG has some drawbacks such as the need for a second surgical site to harvest graft increases treatment time and patient morbidity. Bleeding and postoperative discomfort are common after graft harvesting. Another issue is a limited amount of tissue is also a concern in multiple defect cases. Patients' willingness to retreat was affected by previous autogenous grafting.

Recently, the use of placental membranes is introduced as a suitable substitute for SCTG. The human placenta is composed of two membranes inner amniotic and outer chorionic membranes. These membranes secrete anti-inflammatory cytokines and growth factors such as platelet-derived growth factor AA (PDGF-AA) and vascular endothelial growth factor (VEGF). These membranes have anti-inflammatory, angiogenic, antifibrotic, and antimicrobial effects. Furthermore, they have low immunogenicity and improve epithelization. They have been widely used in medicine since the 1910s with increasing clinical applications from wound care and ophthalmology, to plastic surgery.

There is a growing interest in using placental allografts as a substitute for conventional membranes in oral surgical procedures. They are used for root coverage as a substitute for SCTG as these membranes contain different types of collagen, proteoglycans, laminin, and bioactive factors which help in binding gingival epithelial cells to the root surface. They act as reservoirs of stem cells which promote cell differentiation, stimulate healing, and help in revascularization.

So in this study, it is proposed to evaluate Amnion Chorion membrane in the management of gingival recession type 1 in comparison to SCTG.

Aim of the study The primary outcome is to evaluate the effectiveness of the Amnion Chorion membrane (ACM) in the management of gingival recession type 1 (RT1).

The secondary outcome is to compare between ACM and subepithelial connective tissue graft in the treatment of recession defect type 1 (RT1).

Inclusion Criteria:

1. Selected patients of both sexes are 25-45 years old.
2. Patients are systemically healthy based on the questionnaire dental modification of the Cornell index.
3. O'Leary index (1972) is less than 10% (the surgical therapy is not initiated until the patient reaches the 10% level or less of plaque accumulation).
4. Buccal recession defects are classified RT1 according to Cairo's classification (2011).
5. Clinical indication and/or patient request for recession coverage.

Exclusion Criteria:

1. RT2 and RT3 recession defects.
2. Pregnant female.
3. Smokers.
4. Patients with special needs or with any mental problems.
5. All patients are using any kind of medication that could interfere with the healing of periodontal tissues. Such as chemotherapy and radiotherapy.
6. Teeth with root carious lesions.
7. Rotated and extruded teeth.
8. Patients underwent any prior periodontal surgery in the relevant region.

All of the individual participant data collected during the trial, after deidentification.

Immediately following publication. No end date.

Data are available indefinitely at (Link to be included).