Problem #8: Difficulty Capturing 2nd and 3rd Molars on Periapical Images

Discussion: It is often difficult to position the sensor in the molar area. The bite can move the sensor holder forward towards the premolars or the patient may be uncomfortable with the holder in that position, triggering the gag reflex. Lift the chin to drop the tongue back and away to alleviate this feeling.

Solution: The sensor does not have to be placed so far posterior that the patient is uncomfortable. Remember the path of radiation statement one more time: The path of radiation must include the area of interest (teeth and surrounding bone) and active sensor. Change the path to cross the area from behind. Position the tubehead towards the ear and set the horizontal angulation of the radiation path forward across the most distal molar. The sensor can be placed as far posterior in the mouth as is comfortable. The interproximal contacts will be overlapped, but the root apices of the molars will be visible (Figure 35).

Figure 35 - Distal Molar Periapical.
Redirecting the PID posterior to the aiming ring to ensure coverage of radiation over the Maxillary third molar and distal tuberosity.

Figure 35 - Distal Molar Periapical.
Redirecting the PID posterior to the aiming ring to ensure coverage of radiation over the Maxillary third molar and distal tuberosity.