Pacific Coast Society of Orthodontists Bulletin Spring 2018 - 45

Presentation Summary

transverse requirements should be evaluated
on a case-by-case basis to check for the need of
expansion in the absence of any transverse problems. As orthodontists, we should note that the
maxilla is almost always easier to manipulate
than the mandible.
Increasing Frequency of Malocclusion
in Modern Civilizations
In a comparison of individuals who lived in Finland during the 1600s vs. the 1950s, a significant
increase is noted in distal bite, posterior crossbite, deep bite, and maxillary crowding. In addition, enlarged turbinates and deviated septums
are more common now.
When cephalometric features of Finns born
around 1600 were compared with those born
around 1930, the following differences were
noted:3
 Larger rami, increased posterior face heights,
smaller gonial angles, more horizontally
oriented mandibular bases, more palatally
inclined upper incisors, smaller interincisal
angles, and more pharyngeal spaces.
The assumption is that a lack of masticatory
function - and not genetics - might be considered a strong etiological factor in developing
malocclusions in modern industrialized civilizations. Additional evidence is needed to confirm
such a conclusion.
Predictability of Class II Malocclusion
Although the Angle classification is useful in
defining Class II malocclusions, it oversimplifies
the complex pattern of skeletal, dental, and
profile relationships and other characteristics.
Orthodontists' ability to successfully treat Class II
malocclusions depends on their ability to manipulate the dentoalveolar structures, especially the
maxilla. Transverse interarch discrepancy due to
a narrow maxillary intermolar width may be
considered a possible functional cause of distocclusion in Class II Division 1 malocclusions.4
Most well treated Class II malocclusions in growing patients show a significant increase in the

Doctors

transverse dimension of the maxillary dental
arch. This concept appears to be valid except in
the case of true micrognathic mandibles, which
do not respond well to conventional orthodontic
treatment without consideration of either maxillary premolar extractions (profile permitting) or
orthognathic surgery.
Indirect Bonding
The accurate placement of fixed orthodontic
appliances is the key to clinical excellence. Most
studies that attempt to compare accuracy of
bracket placement with either direct or indirect
techniques are inherently flawed due to uncertain measurement accuracy, the Hawthorne
effect, or a lack of heterogeneity. Indirect bonding,
first introduced by Silverman and Cohen, can be
simple, clinician-friendly, accurate, and reproducible.5 Rebonding due to poor initial bracket
placement is minimized, and there is less need
for wire bending. Dr. Moskowitz reviewed his protocol and technique for indirect bonding in detail.
Retention
A relatively simple and direct method of placing a
mandibular 3-3 fixed lingual retainer is to use
Ortho FlexTech material. Any raised marginal
ridges on the retained tooth surfaces should be
reduced and smoothed before bonding.6 For
patients with severely compromised periodontal
conditions, Dr. Moskowitz illustrated a lingual
retainer placed in an unconventional way. A thin
channel was created on the palatal surfaces of
the upper incisors, where the fixed retainer was
inserted with a wire in the channel and then covered with bonding material. This extreme type
of retention would only be reserved for patients
with significant alveolar bone loss. This type of
fixed retention is a variation of an old periodontal
device called an "A" splint. A new type of lower
lingual fixed retainer by AOA Orthodontic Applicances, called MEMOTAIN®, was also discussed.
Its new design engages into embrasures, not just
lingual surfaces of the lower anterior teeth. It is
constructed of a nickel-titanium wire that has
been robotically bent using new technology. This
continued on page 49

Spring 2018  PCSO Bulletin

Table of Contents for the Digital Edition of Pacific Coast Society of Orthodontists Bulletin Spring 2018