The goal of this clinical trial is to assess the efficacy of chitosan as a socket preservation material after tooth extraction in compare to the standard treatment. The study will include patients who exhibit hopeless tooth without any periodontal infection. Smokers, history of allergy, patients with major medical issue and pregnant women will be excluded from the study. The main question[s] to answer is : is there a significant difference in bone density and dimension between the test and control groups after tooth extraction or not.

Participants will be asked to do CBCT scan and take upper and lower impressions before extraction and after three month from extraction. Then, the patients will randomly assigned to one from these groups: There will be a total of three groups (10 patients for each), first group will be treated using mixed of chitosan and allograft, second group will be treated using allograft alone and the last group will be used as control. All patients will be treated in accordance with the 2013 Declaration of Helsinki.

To evaluate the tissue response, intraoral impressions and X-ray will be taking from each patient before extraction and three months after. Also, Cone-beam computed tomography (CBCT) will be taking to measure the bone growth at base line and three months after surgery is done. For measurement, each socket will be vertically divided into 3 equal areas: coronal, middle, and apical. Regenerated bone density will be assessed in each area, in both control and intervention groups.

Data then can be analyzed using SPSS ver. 11 (SPSS Inc., Chicago,USA). P-values less than 0.05 were considered as significant.

Inclusion Criteria:

• Clinical diagnosis of hopeless tooth.
• Healthy patient.
• Healthy gingiva without any periodontal disease.
• Patient is welling to come after three months.

Exclusion Criteria:

• Smokers.
• History of allergy.
• pregnant women.
• patient with systemic disease.

For randomization, The investigator will send a form to the study therapist who is not involved in assessing outcome of the study. This form will include a randomization number. In the clinic, closed envelopes with printed randomization numbers on it are available. For every randomization number the corresponding code for the therapy group of the randomization list will be found inside the envelopes. The therapist will open the envelope and will find the treatment protocol to be conducted in this patient. Staff responsible for recruitment and outcome assessor is not allowed to receive information about the group allocation.