Examination and Diagnosis
Ashman Department of Periodontology and Implant Dentistry, New York University College of Dentistry, New York, NY, USA
In addition to an accurate and thorough clinical examination, a radiographic analysis of each patient is warranted in order to provide a catered diagnosis. Diagnostic imaging modalities help to develop and implement cohesive and comprehensive implant treatment plans. Selection of proper imaging modalities is important to both limit radiation to the patient and accurately diagnose.
Cone Beam Computed Tomography
Cone beam computed tomography (CBCT) provides a diagnostic and measurable three‐dimensional interpretation of bone and soft tissue. This allows the practitioner to localize anatomic features for implant placement and avoid delicate structures such as nerves, arteries, etc. X‐ray beams in this tool are divergent, forming a cone. Originally designed and used in the medical field, advances in the limitations of radiation dosage have allowed the CBCT to be used in dental offices. During the CBCT, the machine rotates around the patient’s head while obtaining hundreds of images. This set of images is referred to as the volumetric data set. The scanning software analyzes and interprets this data to reconstruct a three‐dimensional image of the hard and soft tissue (Pal et al. 2010). While the CBCT shares many similarities to the tradition CT scan used in medicine, there are many differences in the reconstruction of the image. A CBCT alone does not provide the exact position and orientation of a prosthetically driven implant; however, in conjunction with diagnostic templates, this precision may be achieved. Types of diagnostic templates include: Vaquform, acrylic, templates fabricated with radiopaque denture teeth, complex tomography, and panoramic radiography (Misch 2014). Vaquform templates are used on a diagnostic cast with wax‐up. The material uses barium sulfate which will be radiopaque on the CBCT. This method of template production allows the visualization of restorations and tooth borders, however does not indicate the exact position nor orientation of the proposed implant. This method can further be altered by drilling a 2 mm channel through the ideal prosthetic position of the implant crown. This will align with the implants ideal position, and be visible on the CT examination. The second modality of template production is an acrylic template. Similar to the Vaquform method, this allows for drilling of a channel and filling this void with gutta percha to visualize the ideal position of the implant on the scan (Asher et al. 1999). The third technique includes using radiopaque denture teeth. An additional advantage of denture teeth is that the template/stent can be modified for use as a surgical stent. Lastly, the complex tomography, and panoramic radiography techniques can be utilized. They involve placing ball bearings to align with the implant positions and curvature of the arch (Shannoun et al. 2008). These modalities are seldom used, however are available.
Patients never really want implants. What is truly desired is the most convenient, safe, and predictable way to restore oral function AND in most cases oral facial esthetics. In the case of implant dental reconstruction, in order to obtain the most satisfactory outcome for the patient and dentist, this requires absolute prioritization of what the patient wants and how they look at themselves during and after treatment. Thus, it is imperative to provide patients with all information pertaining to treatment considerations and procedures. In order to predictably accomplish this, the relevant medical and dental history, physical examination, especially critical anatomic and physiological parameters, and understanding of the benefits and limitations of each implant system and method are essential.
Esthetics naturally remains one if not the major concern for a patient and can be extremely challenging considering the effects of aging, post‐dental tooth loss resorption, and anatomic and medical considerations. For the population seeking permanent fixture options, often the best esthetic and functional result may not be the most complex or necessitate absolute replacement of each lost tooth with an implant fixture. Rather, the intrinsic mechanics of occlusal forces and restoration of hard and soft tissues is more important. Also, since implant procedures are costly and time consuming this aspect of treatment is often most perplexing for the patient and the dental provider. Accurate and reliable evidence‐based decisions along with immediate and long‐term risks and benefits are often excluded or not fully understood and can lead to dissatisfaction and/or further oral health deterioration.