Dental Implants - The Planning of Implants Using 3D Conebeam Computed Tomography

When you are missing a tooth or teeth or have to have a tooth or teeth removed likely you will need to have the tooth or teeth replaced. The modern replacement method is with a dental implant. Dental implant planning has come a long way since the days of a small rectangular film (periapical radiograph) and holding up to a light to "see" if there was enough room for an implant. These 2 dimensional films only allow the surgeon to evaluate the height of the bone and the distance between the roots of the adjacent teeth. Since x-ray technique can alter appearance, the distances can be misleading and can create intraoperative difficulties during implant placement. Additionally there can be magnification of the x-ray giving the surgeon a false sense of security to important adjacent anatomy like the sinus and the inferior alveolar nerve canal. The inferior nerve canal is where the nerve that supplies feeling to your lower teeth and lip and chin resides. It is the nerve that the dentist "numbs" and your lip and chin feels fat and funny. As such, implants placed too deeply based on magnified films can lead to paresthesias and/or dysesthesias of the inferior alveolar nerve (paresthesia is an altered sensation and dysesthesias are painful alterations in feeling).

Since typical radiographs are two dimensional, they give little evidence in the bony width. Frequently after extractions the bone can become too thin to accept a dental implant. To place an implant in that situation, the patient may have to undergo a bone grafting procedure(s). Often, these discoveries are made at the time of surgery. Thankfully, today, there are methods to take the guesswork out of implant planning and minimize the risk of surgery to the patient.

With affordable conebeam computed tomography radiographs, accurate three dimensional representations of the patient's bone and even soft tissues can be replicated on a computer. Using planning software, like the one from Materialise called Simplant, the surgeon can inspect the patient's bony foundation on the computer. Measurements, bone quality, positions of adjacent teeth, position of adjacent vital anatomy are accurately represented. Bone grafting, sinus augmentations, nerve repositioning and bone harvest site can be planned ahead of time. Implants can be virtually placed in the planning software and then surgical guides can be created that guide the surgeon to exactly replicate the plan on the computer and stop the implant drills short of adjacent anatomy. This helps prevent injury to the patient.

In the near future, companies like Tactile-Tech are close to developing technology that will allow dental implants to be placed by surgeons using real time imaging. This means they will be able to "see" into the patient's bone while placing implant and be able to see exactly what is going on during the entire surgery in 3 dimensions. Advances in technology are making the placement of dental implants more precise and are drastically reducing post-operative complications for patients.