radiography : waters

1. Watersprojection

2. Image Receptor and Patient Placement
image receptor : in front of the patient and perpendicular to the
midsagittal plane
patient’s head : tilted upward , canthomeatal line forms a 37 degree
angle with the image receptor
If mouth is open: sphenoid sinus is seen superimposed over the palate

3. Position of Central X-Ray Beam
central beam is perpendicular to the image receptor and
centered in the area of the maxillary sinuses.

5. Resultant Image
The midsagittal plane should divide the skull image
into two symmetric halves.
The petrous ridge of the temporal bone should be
projected below the floor of the maxillary sinus.

6. Interpretation
a systematic approach like lateral and PA cephalometric
projections that ensures interrogation of the complete image.

8. According to the table :
High usefulness :
Coronoid process , orbit ,
zygoma , maxillary sinus
Not recommended :
Mandible , condylar neck

9. Thanks for your attention