Case of the month: Dental implant & CBCT

A patient presented for removal of a broken tooth and immediate dental implant placement. A moment of concern was raised following results generated by the appearance of the 2 dimensional plain intra-oral X-ray image. Prior to examining reason of concern, here is a brief description of images:

(from left to right)
Image 1: X-ray of patient’s teeth. Arrow points to broken tooth in question.
Image 2: X-ray of patient’s teeth reflecting immediate implant placement.  Arrow points to area of concern, showing potential collision between dental implant and adjacent tooth.
Image 3: Post operative check using Cone beam computed tomography (CBCT), a medical 3D imaging technique. Image of patient’s teeth with limited field of view of the upper jaw. Arrow points to same area as in image 2, same area of concern.

The concern? Given that the patient has a pronounced gag reflex, positioning of the sensor in her mouth was compromised and resulted in inappropriate X-ray image angulation. The inappropriate position of the intra-oral X-ray sensory created a 2 dimensional illusion or image distortion of an incorrectly positioned implant, the apex appearing to impinge on the tip of the root of the adjacent tooth (see white lines in image 2). This  “illusion of misalignment” becomes obvious when comparing image 2 with image 3 in which we see the more parallel, correctly aligned position of dental implant and adjacent tooth (compare white lines in image 2 with those in image 3).

“Thankfully, a CBCT post operative safety check image immediately confirmed appropriate implant position. This alleviated our concerns regarding the long term status of the adjacent tooth” Dr.Antoine Chehade.

We do not routinely advocate the use of CBCT, 3D imaging after all implant cases. We use this technique under exceptional circumstances for the imaging and diagnoses of a variety of conditions and clinical situations such as this one.

And this was a case worth sharing!