Pacific Coast Society of Orthodontists Bulletin Spring 2020 - 53

Doctors

Presentation Summary

Palatal Expansion With Skeletal
Anchorage: Periodontal and Airway
Rationale
Dr. Renelle Connor
PCSO Bulletin Contributor

Presented by Dr. Marianna Evans at the PCSO
Annual Session, Oct 3, 2019
Dr. Marianna Evans is a board-certified specialist in both periodontics and orthodontics and
a private practice owner in Pennsylvania. As a
dual specialist, Dr. Evans shared her experiences
in palatal expansion using skeletal anchorage:
"My presentation is going to focus on growing
bone around the buccal of the teeth with skeletal
expansion."

Dr. Marianna Evans
Infinity Dental Specialists

When Starting Cases, Dr. Evans Recommends the
Following Treatment Goals
▫▫ Facial esthetics
▫▫ Upright teeth within the basal bone to relieve
axial loading
▫▫ Maximum intercuspation
▫▫ Minimal centric relation-centric occlusion
discrepancies
▫▫ Airway-protective results
Why Consider Orthodontics Instead of Periodontics for Bone Growth?
Periodontal techniques are improving at increasing the amount of buccal bone, but there are
limitations, and not all patients respond favorably to such techniques. Periodontal phenotypes
respond differently to different treatments, and
phenotype B is more susceptible to bone loss.
Orthodontics can be used to place the teeth in
the bone and grow basal bone and palatal bone.
Because patients respond differently to periodontal treatment, with some of them experiencing
bone resorption, surgical treatment is not always
the answer for increasing buccal bone.
Protocol for Expansion
Dr. Evans expands skeletally mature patients using temporary skeletal anchorage devices (TSADs)
for skeletal bone anchorage. Expansion is created
to open the sutures so that the teeth can be not
only centered in the basal bone, but also uprighted axially. She states, "Once those teeth are
uprighted axially within the basal bone, we load
them with special myofunctional exercises for

Spring 2020 PCSO Bulletin

one hour a day with vertical rubber bands." This
protocol allows for a "buttressing-bone effect,"
and "this technique produces more bone than
other orthodontic techniques." The amount of
expansion is based on the canine, and expansion
is continued until the canine is upright. This is important because "if canines are not upright, then
there will be interferences before guidance kicks
in." Cases are finished by using braided stainless-steel wire and vertical elastics for settling.
Suture Consideration for Expansion
Expansion using skeletal anchorage causes expansion of the midface and engages the maxillary and circummaxillary sutures. The midpalatal
suture does not close during life. With aging, the
midpalatal suture becomes more interdigitated,
increasing the surface area contact between
the two halves of the palate. Circummaxillary
sutures, such as the pterygomaxillary, temporozygomatic, and zygomaticomaxillary sutures, may
play a part in limiting expansion in adults. Discrepancies in suture strength between the right
and the left sides of the face have the potential to
cause asymmetries with expansion.
Airway Considerations for Expansion
Dr. Evans explained that most people with sleep
apnea have nasal resistance. For this reason,
orthodontists should consider skeletal expansion
when the maxillary requires expansion if upper
airway resistance is a concern.
Soft-Tissue Considerations for Palatal Expansion
With Skeletal Anchorage
Dr. Evans' protocol for expansion has shown that
when the palatal skeletal expansion is greater
than 5 mm, midface hard-tissue changes are
seen radiographically and soft-tissue changes are
visible. "The nose will become wider, and the skin
around the eyes looks more relaxed."
Rationale for Using TSADs for Expansion
With increased interdigitation of the midpalatal
suture, it becomes more difficult to separate
the two halves of the maxilla. When the patient

Pacific Coast Society of Orthodontists Bulletin Spring 2020

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