A New System in Guided Surgery

In this chapter the authors describe a new system for guided surgery in implantology. The aim of this system is to have a “user friendly” computerized instrument for the oral surgeon during implant planning and to have the dental lab included in the decisional process. This system gives him the possibility to reproduce the exact position of the implants on a stone model; the dental technician can create surgical guides and provisional prosthesis for a possible immediate loading of the implants. Another objective of this system is to reduce the economic cost of surgical stents; in such a way it can be applied as a routine by the surgeon.

Automated Bacterial Colony Counting for Clonogenic Assay

Bacterial colony enumeration is an essential tool for many widely used biomedical assays. This chapter introduces a cost-effective and fully automatic bacterial colony counter which accepts digital images as its input. The proposed counter can handle variously shaped dishes/plates, recognize chromatic and achromatic images, and process both color and clear medium. In particular, the counter can detect dish/plate regions, identify colonies, separate aggregated colonies, and finally report consistent and accurate counting result. The authors hope that understanding the complicated and labor-intensive nature of colony counting will assist researchers in a better understanding of the problems posed and the need to automate this process from a software point of view, without relying too much on specific hardware.

Virtual Dental Patient

The availability of datasets comprising of digitized images of human body cross sections (as well as images acquired with other modalities such as CT and MRI) along with the recent advances in fields like graphics, 3D visualization, virtual reality, 2D and 3D image processing and analysis (segmentation, registration, filtering, etc.) have given rise to a broad range of educational, diagnostic and treatment planning applications, such as virtual anatomy and digital atlases, virtual endoscopy, intervention planning etc. This chapter describes efforts towards the creation of the Virtual Dental Patient (VDP) i.e. a 3D face and oral cavity model constructed using human anatomical data that is accompanied by detailed teeth models obtained from digitized cross sections of extracted teeth. VDP can be animated and adapted to the characteristics of a specific patient. Numerous dentistry-related applications can be envisioned for the created VDP model. Here we focus on its use in a virtual tooth drilling system whose aim is to aid dentists, dental students and researchers in getting acquainted with the handling of drilling instruments and the skills and challenges associated with cavity preparation procedures in endodontic therapy. Virtual drilling can be performed within the VDP oral cavity, on 3D volumetric and surface models (meshes) of virtual teeth. The drilling procedure is controlled by the Phantom Desktop (Sensable Technologies Inc., Woburn, MA) force feedback haptic device. The application is a very promising educational and research tool that allows the user to practice in a realistic manner virtual tooth drilling for endodontic treatment cavity preparation and other related tasks.

Rapid Prototyping and Dental Applications

The present chapter deals with the introduction and implementation of rapid prototyping technologies in medical and dental field. Its purpose is to overview the advantages and limitations derived, to discuss the current status and to present the future directions, especially in dental sector. Furthermore, a flowchart is outlined describing the procedure from the patient to the final 3-D object, presenting the possible alternatives in the process. Finally, an example is presented, decribing the process of the construction of high accurate surgical guided templates in dental implantology, through rapid prototyping.

Haptic-Based Virtual Reality Dental Simulator as an Educational Tool

This chapter describes the haptic dental simulator developed at the University of Illinois at Chicago. It explores its use and advantages as an educational tool in dentistry and examines the structure of the simulator, its hardware and software components, the simulator’s functionality, reality assessment, and the users’ experiences with this technology. The authors hope that the dental haptic simulation program should provide significant benefits over traditional dental training techniques. It should facilitate students’ development of necessary tactile skills, provide unlimited practice time and require less student/instructor interaction while helping students learn basic clinical skills more quickly and effectively.

Digital Library for Dental Biomaterials

In this chapter, the author will demonstrate and describe a project to develop a unique database with multilingual information and knowledge resource for biomedical dental materials and their properties. The database will be populated with high-quality, peer-reviewed information, equipped with an original search engine which would include all necessary information to (1) do standardization of therapeutic treatments (2) understand, the tissue response to biomaterials; (3) identify biomaterials and tissue matrix environment, to allow deeper understanding of the underlying relationship which allow more effective device design and engineering; (4) develop enabling tools by improvements in high-throughput assay and instrumentation, imaging, modalities, fabrication technologies, computational modelling and bioinformatics;(5) promote scale up, translation and commercialisation.

Advances and Trends in Tissue Engineering of Teeth

Tooth loss due to several reasons affects most people adversely at some time in their lives. A biological tooth substitute, which could not only replace lost teeth but also restore their function, could be achieved by tissue engineering. Scaffolds required for this purpose, can be produced by the use of various techniques. Cells, which are to be seeded onto these scaffolds, can range from differentiated ones to stem cells both of dental and non-dental origin. This chapter deals with overcoming the drawbacks of the currently available tooth replacement techniques by tissue engineering, the success achieved in it at this stage and suggestion on the focus for future research.

3D Reconstructions from Few Projections in Oral Radiology

Established techniques for three-dimensional radiographic reconstruction such as computed tomography (CT) or, more recently cone beam computed tomography (CBCT) require an extensive set of measurements/ projections from all around an object under study. The x-ray dose for the patient is rather high. Cutting down the number of projections drastically yields a mathematically challenging reconstruction problem. Few-view 3D reconstruction techniques commonly known as “tomosynthetic reconstructions” have gained increasing interest with recent advances in detector and information technology.

Denoising and Contrast Enhancement in Dental Radiography

This chapter shows how large improvement in image quality can be obtained when radiographs are filtered using adequate statistical models. In particular, it shows that impulsive noise, which appears as random patterns of light and dark pixels on raw radiographs, can be efficiently removed. A switching median filter is used to this aim: failed pixels are identified first and then corrected through local median filtering. The critical stage is the correct identification of the failed pixels. We show here that a great improvement can be obtained considering an adequate sensor model and a principled noise distribution, constituted of a mixture of photon counting and impulsive noise with uniform distribution. It is then shown that contrast in cephalometric images can be largely increased using different grey levels stretching for bone and soft tissues. The two tissues are identified through an adequate mixture derived from histogram analysis, composed of two Gaussians and one inverted log-normal. Results show that both soft and bony tissues become clearly visible in the same image under a wider range of conditions. Both filters work in quasi-real time for images larger than five Mega-pixels.

Visualization and Modelling in Dental Implantology

Intraoperative transfer of the implant and prosthesis planning in dentistry is facilitated by drilling templates or active, image-guided navigation. Minimum invasion concept of surgical interaction means high clinical precision with immediate load of prosthesis. The need for high-quality, realistic visualization of anatomical environment is obvious. Moreover, new elements of functional modelling appear to gain ground. Accordingly, future trend in computerized dentistry predicts less use of CT (computer tomography) or DVT (digital volume tomography) imaging and more use of 3D visualization of anatomy (laser scanning of topography and various surface reconstruction techniques). Direct visualization of anatomy during surgery revives wider use of active navigation. This chapter summarizes latest results on developing software tools for improving imaging and graphical modelling techniques in computerized dental implantology.