acific Coast Society of Orthodontists Bulletin Summer 2018 - 55

Presentation Summary

Lips Rule: The Functional Esthetic Dental
and Skeletal Requirements for Beautiful Lips
Dr. Bruce P. Hawley
PCSO Bulletin Columnist

Presented by Dr. Michael Gunson, PCSO Annual
Session, Reno, NV, October 13, 2017
Dentists and orthodontists have a great influence over the esthetic appearance of the lips. The
position, form, and relationship of the skeletal,
dental, and soft tissue parts in the head have a
direct effect on their appearance and function.
This is also true when a patient receives crowns,
veneers, splints, orthognathic surgery, or orthodontics. Proper diagnosis and treatment of
patient dysfunction can create, preserve, or
restore beautiful lips at any age.

Dr. Michael Gunson
Santa Barbara, CA

According to Gregory Bateson, the pathology "is
not in the thing, it is in the system, in the pattern
of the relationship between the things." The dental history of defining facial esthetics has been
about the position of parts: bones (through cranial base analysis), teeth (through digital smile
design), and face (by such proponents as Arnett
and Andrews). Most analyses describe only positions in space, and not function, and the "why"
questions are not answered. Andrews used 120
"normal" patients, and Arnett described 100
"beautiful" patients. Normative data used to
treat patients will provide only average results.
Relying on the individual's functional requirements will allow us to routinely achieve excellent
results. Therefore, we need a means of diagnosing patients that is non-normative - a system
based on patterns and not things, and which
answers the "why" of the face.
Biological Esthetics - Lips
The purposes of lips include respiration, mastication, perception, and communication. We are
obligate nasal breathers. The lips close to keep
food inside the mouth, and our teeth touch during swallowing. The lower lip is the primary oral
facial proprioceptive organ. In communication,
lips participate in our facial expressions. Lips
relate to teeth during F and V sounds, and lips
relate to lips during P, B, M, and W sounds.

Summer 2018  PCSO Bulletin

Functional Facial Keys and Lips
In the horizontal plane of space, the maxillary
anterior teeth need to support the upper lip and
be in a harmonious relationship with maxillary
alveolar and basal bone. They also need to correctly touch the lower lip for proper proprioceptive feedback. In the vertical plane, the lips must
close passively, and not overclose. In closing one's
mouth, the superior orbicularis oris muscle moves
down, and the inferior orbicularis oris moves up.
If this is too difficult for the individual, the mentalis muscle is recruited to assist in elevating
the lower lip. The pterygoid muscles would then
be recruited, if needed, to move the mandible
upward and forward. Finally, if the preceding is
too difficult, the neck muscles (cervicus and capitis) are brought into play through extension of
the neck. Patients may have difficulty closing
their mouths due to developmental, acquired,
trauma, iatrogenic, or habit-related reasons.
Historical and Clinical Background
In 1870, George Catlin, an American explorer and
painter, published Shut Your Mouth and Save Your
Life. Catlin described the lack of lip seal as having
four major effects, which we can now summarize
as bite problems, facial aesthetic problems, TMJ
dysfunction/facial pain, and airway problems.
Does the malocclusion result in lip incompetency,
which leads to mouth breathing, or is the reverse
true? The vertical dimension of occlusion (VDO)
is a very highly adaptable position, and there is
no single correct vertical dimension. Perhaps we
should be looking at the vertical dimension of
the face rather than the VDO. Individuals with
bites associated with lip incompetency often
show upper lip and mentalis overclosure, vertical
pressure on the lower incisor crowns at the middle third of the teeth, and anterior dental hypereruption with steps in the gingival margins
between the lower incisors and the teeth posterior to them. If creating lip seal is too difficult, the
tongue then seals the mouth, the pterygoids
bring the lower jaw forward posturally, and there

Table of Contents for the Digital Edition of acific Coast Society of Orthodontists Bulletin Summer 2018