Enhancing implant surgery planning via computerized image processing

Abstract

Computerized tomography (CT) and magnetic resolution imaging (MRI) are the medical imaging modalities to deliver cross-sectional images of the human body. In the last decade, CT has become the most frequently used imaging modality for the evaluation of the jaw for dental implants. Furthermore, image reformatting software has been developed in order to obtain a correct preoperative diagnosis and treatment planning regarding osseointegrated implants. Previous work has shown that CT images are affected by a distortion ration from 0% to 6%. This might be due to the alignment of the patient during scanning, to his/her movements, or possibly to the saturation of pixels composing the image. In order to solve the former problem, intraoral stents can be used to center the patient's head perpendicular to the axis of the implant to be inserted. However, if more than one implant must be placed - possibly with very different axes - it would be necessary to acquire the corresponding number of tomograms, each perpendicular to the axis of one planned tooth. Obviously, it would be better not to expose the patient to multiple CT scanning. In this work, we present a software approach for enhancing implants surgery planning in order to obtain exact morphological measurements of the bone and planned teeth with a single CT acquisition. This is achieved by applying image-processing techniques to the original CT images, in order to produce new Ct images lying on different planes, and possibly perpendicular to a different tooth. The resulting software system (Dental/Vox) has been implemented in C+ + and runs on Intel-based personal computers under the Windows operating systems. DentalVox ensures better mechanical results in the design and planning of a dental implant compared to other, similar software tools; it can reconstruct axial (and panorex and cross-sectional) images once any direction is chosen. This makes it possible to implant a mechanically and esthetically superior prothesis in the underlying gnathic morphology