How to Take Good Bitewing X-ray

1. Use #2 sensor routinely
2. For most of new patient exam, we usually take 7 X-ray films: 4 BWs, 3 PAs (or 2).  Three PAs may be two upper anteriors (6,7,8 and 9,10,11) and one lower incisor (23-26), or one upper, one lower and one of posteriors.  Take X-ray in that sequence.  The doctor will re-arrange it
3. If the patient has language difficulty, let the doctor or Lirong take intraoral X-ray, but please help us do set-up: such as placing lead apron, bring in X-ray devices, install the sensor if instructed
4. If you encounter difficulty in taking X-ray, ask for help immediately
5. The 1st BW is for right molars.  The center of the sensor should be on the 1st and 2nd molars.  Ask the patient to push the tongue to the left side, insert the sensor into the lingual vestibule so far the midline of the mouth as possible.  In the end, the upper edge of the sensor is almost on the top of the palate (vault, center of the palate, the highest point).  Ask the patient to bite on the horizontal plate as tight as possible, lift the lips to double check whether upper and lower molars bite on the plate.  In the moment the patient bites on the horizontal plate, you may notice the ring goes down, particularly for the patient with crowding (deep overbite and overjet).  Please raise the X-ray tube a little bit and direct downward to compensate.  Usually we get too much of lower teeth and too little of upper teeth
6. Go outside operatory, choose the right exposure setting, look at the mirror to see whether the sensor is ready or not (green bar on the top of the computer screen).  Hold the exposure button for a while.  If you press incorrectly, signal is blinking.  Press Select button to restore normal setting
7. Please wait for the 1st bitewing to develop (to show up in computer screen).  If there is too much of lower teeth.  Please do not move the device.  Instead move the tube upward and slightly forward so that next X-ray may show more of upper teeth and a little more of premolars
8. For taking 2nd bitewing for right premolars, do not move tube away.  Instead move the sensor forward first so that you can tell whether the sensor has been moved enough or not, by the original position of the tube.  You may ask the patient to bite tight, and raise the lips to see whether the premolars and sensor match each other.  The front end of sensor device almost touches the opposite canines.  When you feel satisfied, adjust the position of the tube to the aiming ring
9. To take 3rd bitewing (for left premolars), flip device over and make sure the front end of device reach the right canines
10. To take 4th bitewing (left molars), you have to move the tube first and adjust the device second
11. Return to Assistant Page

Xin Wei, DDS, PhD, MS 1st edition 06/01/2011, last revision 06/01/2011