In this experiment, after non-traumatic tooth extraction, the blank group underwent natural healing, and the Bio-Oss Collagen underwent alveolar ridge preservation using Bio-Oss Collagen and the Sticky Bone group using Sticky Bone, to verify the application of Bio-Oss Collagen and Sticky Bone in alveolar ridge preservation

Within 6 months after tooth extraction, the remaining alveolar ridge undergoes varying degrees of absorption, resulting in a decrease in horizontal width and vertical height of the alveolar ridge. The three-dimensional size change of the alveolar socket may affect the implantation of later implants and cause aesthetic and functional problems. Alveolar ridge preservation can maintain the volume of the alveolar socket, prevent soft tissue from growing into undesirable positions, slow down the absorption of the alveolar ridge to some extent, promote new bone formation, and maintain the shape of the extraction socket. This is crucial for later implant treatment for missing teeth. In this experiment, after non-traumatic tooth extraction, the blank group underwent natural healing, and the Bio-Oss Collagen group underwent alveolar ridge preservation using Bio-Oss Collagen and the Sticky Bone group using Sticky Bone, respectively, to verify the application of Bio-Oss Collagen and Sticky Bone in alveolar ridge preservation

Inclusion Criteria:

1. The presence of one adjacent tooth at the extraction site
2. Adequate oral hygiene (plaque index <20%;bleeding on probing <25% )
3. Need for tooth extraction due to endodontic，periapical or periodontal disease.
4. Presence of ≥ 2 mm of keratinized tissue
5. the extraction sockets have no more than 50% of buccal alveolar bone loss(Integrity of alveolar bone walls)

Exclusion Criteria:

1. Pregnancy or lactation
2. Smoking more than 10 cigarettes per day
3. with no evidence of acute infection such as severe swelling, suppuration at the extraction site
4. Uncontrolled periodontal disease
5. Existence of bone metabolic disease
6. history of malignancy, radiotherapy, or chemotherapy in the past 5 years
7. Administration of bisphosphonates
8. long-term use of NSAIDs
9. Alcohol or drug abuse
10. Infectious disease, such as hepatitis or human immunodeficiency virus (HIV) and/or acquired immunodeficiency syndrome (AIDS)
11. Uncontrolled severe diabetes.( hemoglobin A1c >6.7%)