Clinical stages in determining the form of the upper rim

Question 1

Step 1

Answer 1

Infranasal tissues are harmonious with the soft tissues of the middle third of the face

Failure to do this may affect the lip form

Question 2

Step 2

Answer 2

Confirm that the upper lip is adequately supported to restore the vermillion border and philtrum

Nasolabial angle should be 90 degrees

Question 3

Step 3

Answer 3

Determine the position of the incisal point relative to the resting lip

Incisal level of the upper rim is 2 mm inferior to the resting uppe lip

Younger pts may be expected to show 4–5 mm of tooth beneath the resting lip, especially if the patient had a Class 2 division 1 profile.

Older pts might be best suited by having the incisal point level with the resting lip, or possibly 1 mm above this

Question 4

Step 4

Answer 4

Determine the upper anterior plane

The plane of the upper six anterior is
made parallel to the interpupillary line.

This may be done using a Fox’s occlusal
plane guide or any device giving a
horizontal plane eg a wooden spatula.

Question 5

Step 5

Answer 5

Determine position of mid-points of upper canines
Using:
1. Photographs (pre-extraction record)
2. Extend dental floss from inner canthus of the eye to lateral border of alar cartilage while patient is smiling

Question 6

Step 5

Answer 6

Determining the position of the mid
points of the upper canine teeth

Useful techniques are
1. Use a photograph (pre extraction
record) of the patient when the patient
was dentate

2. extend dental floss from the inner canthus of the eye, via the lateral border of the alar cartilage (with the patient smiling) onto the incisal edge of the upper rim

Question 7

Step 6

Answer 7

Using the canine points on the upper rim as reference points, the right and left posterior planes are formed.

The accepted guideline is that this plane is parallel to the line drawn from the inferior border of the alar cartilage to a position two-thirds of the way up the tragus

Question 8

Step 7

Answer 8

Creating buccal corriodors is created by reducing the inferior borders of the posterior rims by 3 or 5 degrees by using canintips as a reference