the study aims to assist the different 3D shapes of maxillary sinus in adult individuals among Egyptian population,The data collection will be obtained from the data base available at the department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Cairo University. CBCT images will be obtained from Egyptian patients who were referred to the CBCT unit in oral and maxillofacial radiology department for different purposes. The following radiographic examination will be done in Oral and Maxillofacial Radiology Department, Faculty Dentistry, Cairo University. semiautomated segmentation will be performed for the maxillary sinus in both side and then linear and 3D volume will be assessed for each sinus.

Inclusion Criteria:

• CBCT scans of adult Egyptian patients, males and females, with age range between 18 and 50 years old. Patients will be divided into two age groups (group 1 less than or equal 30 years old, group2 more than 30 years old).
• CBCT scans of patient without previous orthodontic treatment.
• CBCT scans without any other treatment that might interfere with the natural course of maxillomandibular growth and development.

Exclusion Criteria:

-Scans with maxillary pathologies like (tumors, odontogenic lesions, bone lesions).

• Patients with traumatic injuries or fractures affecting the maxillary sinus.
• Patients with missing upper premolar or molar teeth in one side or both sides.
• Patients with skeletal asymmetries, craniofacial traumas and developmental anomalies such as palatal cleft.
• Images of low-resolution quality.
• Distortion of images or presence of any artifacts.

CBCT maxillofacial scans belonging to Egyptian individuals will be examined