Sinus Floor Cortication: Classification and Prevalence

To present a classification and assess the presence and degree of cortication of the sinus floor utilizing Computerized Tomography (CT) scan images.One hundred CT scans, of patient who required a sinus augmentation procedure (SAP), were evaluated and classified according to the Type of sinus floor cortication (SFC). Type 1: sinus floor showing similar or higher density than the surrounding cortical areas. Type 2: sinus floor showing less density than the surrounding cortical areas. Type 3: sinus floor showing no cortical bone. Type 4: sinus floor showing the fusion of sinus floor bone and native crestal bone.The SFC were present in 31, 41, 18, and 10 cases in Type 1, 2, 3, and 4, respectively.This classification based on the level of cortication of the sinus floor is clinically useful as a method of determining if the dental implant can be placed simultaneously or not with the SAP, or can be placed even without a SAP.