Implant-guided Volumetric Analysis of Edentulous Maxillary Bone With Cone Beam CT Scan. Maxillary Sinus Pneumatization Classification

Abstract

Abstract Purpose: The primary goal of this anatomic study was to measure the average bone volume of the edentulous maxilla with a CBCT scan and determine its suitability for implant treatment without additional bone grafting. The secondary goal of the study was to estimate the degree of sinus pneumatization in reviewed CBCT scans, assess the maxillary sinus-to-maxillary bone inter-relationship in edentulism, and attempt to classify maxillary sinuses based on the degree of their pneumatization.Patients and Methods: This retrospective radiographic quantitative study consisted of the analysis of CBCT scans of randomly selected 30 maxillary edentulous patients who presented in 2008-2010 to the University of the Pacific, School of Dentistry for evaluation and treatment of their edentulism. A volume of edentulous maxillary bone mesial to the maxillary sinuses (inter-sinal region) that can be used for a full-arch implant treatment was evaluated based on specifically selected and clinically relevant measurement criteria.Results: There were 30 CBCT scans of maxillary edentulous patients reviewed (9 males, 21 females) with a mean age of 67.3 years old (range from 41 to 92 years old). The total mean maxillary bone volume (MMBV) suitable for implantation was 4,408.1 mm3 and ranged from 1,489.7 to 7,263.1 mm3.Conclusion: Although many other clinical criteria are important (bone quality, alveolar crest anatomy, etc.), the results of this CBCT radiographic study indicate that in many maxillary edentulous cases the existing bone quantity (volume) can be sufficient for a full-arch maxillary implant treatment with at least 4 implants without the additional trauma or expense of bone grafts and sinus lifts. A variety of implant treatment options can be proposed based on maxillary bone availability and bone to sinus inter-relationship. It appears that with age and edentulism, the amount of available maxillary bone is steadily decreasing.