The goal of this clinical trial is to evaluate clinically and radiographically effectiveness and products safety of the collagen membrane (FormaAid®) in the treatment of periodontal regeneration using guided tissue regeneration (GTR) performed by the trained periodontists. The main question it aims to answer are:

• The difference of periodontal status: clinical attachment level (CAL), periodontal pocket depth (PPD), gingival recession (GR), gingival Index (GI) and plaque index (PI).
• The difference of intrabony defect height.
• The difference of gingival tissue thickness and gingival tissue volume.
• The incidences of safety indicators.

Participants will be randomized into either experiment group or control group, undergo guided tissue regeneration (GTR) surgery at week 1, and re-visited on week 3, 5, 13 and 27 after the GTR surgery.

Researchers will compare if the test product is non-inferior to Bio-Gide.

This study is conducted as a randomized controlled clinical trial regarding the use of two different marketed collagen membrane with freeze-dried bone allograft (FDBA) in treatment of periodontal intrabony defects. Collagen membrane acts as a barrier that prevents soft tissue (gums) from growing into the area where bone regeneration is desired. This allows the bone and other necessary tissues to regenerate more effectively. Sutures are removed 14 days after the surgery. Patients are then followed up at 5, 13- and 27-weeks post-surgery for Gl, PI, GR, PPD, and CAL to evaluate the tissue condition. The cone beam computed tomography (CBCT) and the X-ray radiographic evaluation will be assess in this study twice before and after treatment week 27 on the investigational site. And all subjects will receive intra-oral scanning with an intra-oral scanner at baseline and week 5, 13, 27 follow-up visits to assess the gingival tissue thickness and gingival tissue volume change. Safety data and adverse events would be recorded throughout the study.

Inclusion Criteria:

• Age between 18 70 years old, male or female
• Non current smoker: A person who has not smoked more than 100 cigarettes from the past to the present and has not smoked in the last 30 days.
• Patients who have decided to pay at their own expense and require guided tissue regeneration (GTR) for periodontal regeneration
• The defect morphology of intrabony defects is 2 or 3 wall intrabony defect.
• Periodontal pocket depth ≥ 5mm (probing periodontal depth, PPD, distance from gingival margin to the bottom of the defect).
• The height of the bone defect in the X ray image is ≥ 3mm (according to the X ray film intraosseous defect)
• The diagnosis of periodontal disease is stage III with either grade B or C.
• Patients who are willing to adhere to the study protocol and sign the informed consent form.
• Willing to accept evaluation during the trial period and return to clinic and treatment.
• Not a person subject to a sentence of guardianship or subject to judicial guardians.

Exclusion Criteria:

• Have a history of severe allergies or be allergic to collagen.
• Those who are known to be positive for human immunodeficiency virus.
• Poorly controlled diabetes (untreated or unstable disease status), blood test measurement of glycated hemoglobin greater than 7%
• Undergoing chemotherapy three months before agreeing to this experiment.
• Patients undergoing meat product desensitization treatment.
• Have a documented history of osteoporosis.
• Chronic disease, hypertension, hyperlipidemia, cardiovascular disease, and stroke not properly controlled (untreated or unstable disease condition) judged by the investigator at screening.
• Suffering from autoimmune diseases or connective tissue diseases, such as systemic lupus erythematosus or dermatomyositis.
• Coagulation disorder, lab test prothrombin time (PT) > 12 sec , or the use of anticoagulants that affects surgery judged by the investigator at screening.
• The tooth for which guided tissue regeneration (GTR) surgery is to be performed is determined to be furcation involved by investigator from image evaluation
• The tooth for which guided tissue regeneration (GTR) surgery is to be performed is considered unhealthy, exhibiting conditions such as apical lesion, needed endodontic therapy tooth, tooth fracture, etc. etc., as judged by the investigator f rom image evaluation
• Oral mucosal abnormalities or poor periodontal health, making it unsuitable for GTR surgical treatment, such as white spots, erythema, oral submucosal fibrosis, lichen planus, verrucous hyperplasia, inflammation, infection, etc. judged by the investigator at screening.
• Those whose periodontal cleaning is not in good condition or who are unable to cooperate with periodontal cleaning. Plaque control index (O'Leary index) >15%
• The mobility of the teeth that are to undergo guided tissue regeneration (GTR) surgery is greater than or equal to
• Teeth that are to undergo guided tissue regeneration (GTR) surgery have incomplete adjacent teeth on both sides, such as dental prostheses, crowns or bridges, artificial dental implants, or metal fillings. materials, etc., so as to affect the image evaluation.
• Others who are not suitable to participate in or continue this clinical trial as assessed by a physician.