Lecture three
Soft tissues profile
analysis
Soft tissue landmarks
Proportional analysis:
Frontal third: tr-n = 1/3
Nasal third: n-sn = 1/3
Gnathic third: sn-gn = 1/3
n-sn = 45%
sn-gn = 55%
1- Ricketts lip analysis
The reference line used by Ricketts(esthetic line) tip of nose to
skin pogonion
Upper lip 2-3 mm behind this line
lower lip 1-2 mm behind this line
Esthetic line
2- Steiners lip analysis:
Reference line is center of (S) shape between tip of nose and
upper lip and soft tissue pog.
If lips behind this line too flat.
If lips anterior to it too prominent.
3- Holdaway analysis
Harmony line (Holdaway line):
Vermelian border of upper
lip to a tangent of the soft
tissue pog
Holdaways lip analysis:
Angle between a tangent to the upper lip and the NB line (H angle)
ANB angle of 1-3⁰ H angle should be 7-8⁰.
Holdaway define the perfect profile as:
a. ANB angle 2 H angle 7-8
b. Lower lip touching soft tissue line
c. The relative proportion of nose and upper lip are balanced (soft
tissue line bisects the S curve)
d. Tip of nose is 9 mm anterior to soft tissue line.
e. There is no lip tension.
Growth Evaluation
Superimposition on cranial base
structures:
To examine overall changes in
the facial pattern including
changes in maxilla and
mandible in relation to the
cranial base
It is made on:
1- De Coster line
2- SN line
Growth Evaluation
Superimposition on maxilla
To record changes in:
1- Maxilla
2- Maxillary teeth in the maxilla
It is made on :
1- Anterior surface of zygomatic
process
2- Maxillary plane ??!
Growth Evaluation
Superimposition on mandible:
To record changes in:
1- Mandibular teeth in the mandible
2- Remodeling in the mandible
It is made on :
1- Contour of the mandibular canal
2- Inner contour of the cortex of the
mandibular symphysis
3- Tooth bud of the 3rd molar
Other diagnostic records:
These diagnostic aids may be required only in certain cases and
may require specialized equipments, which might not be
available in every dental clinic. These includes:
1- Specialized radiographs: like
a. Occlusal view of maxilla and/or mandible.
b. Selected lateral jaw views.
2- Electromyographic examination of muscle activity.
3- Hand-wrist radiographs.
4- Computed axial tomography (CT scan).
5- Magnetic Resonance Imaging (MRI).
6- Endocrine tests and/or other blood tests.
7- Estimation of basal metabolic rate.
8- Sensitivity (vitality) tests.
9- Biopsy.