In these times of evidence-based medicine (EBM) and dentistry (EBD) we live in, the need for sound clinical research and valid results is indisputable and generally recognized by the scientific community. Whereas there is a rapidly increasing amount of publications about EBM andEBD, they are addressed to medical or dental practitioners and not primarily to clinical researchers. Clinical researchers are supposed to generate clinical evidence. But, the demand for clinical evidence does not create it yet. This book is addressed to all clinicians, associates, and other professionals involved with the generation of clinical information and evidence about the use of medical devices on humans. Thus, it focuses on clinical investigations of medical devices, especially in dentistry.