The document discusses the proper positioning for a Waters projection x-ray exam, including tilting the patient's head upward at a 37 degree angle with the canthomeatal line perpendicular to the image receptor. The central x-ray beam should be perpendicular to and centered on the image receptor in the area of the maxillary sinuses. A properly positioned Waters projection will show a symmetric skull image divided in half by the midsagittal plane and the petrous ridge of the temporal bone projected below the floor of the maxillary sinus.

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