Treating a Class III patient with self-ligating braces
flipped 180 degrees, elastics and buccal shelf TADs
by Dr. Bilal Koleilat
The treatment of Class III dentoskeletal malocclusions can be
divided into three categories: growth modification; camouflage
treatment after cessation of growth; and orthognathic surgery
for severe facial discrepancies. One common point among the three
categories is the lack of maxillary anterior teeth display, resulting
in an unattractive smile and patient dissatisfaction.1
Diagnosis
A 25-year-old patient with skeletal and dental Class III presented
with the chief complaints that his upper teeth didn’t show enough
when he smiled and he didn’t like how his cuspids stuck out.
The extraoral examination revealed a concave general and
subnasal profile, and a thin and retrusive upper lip, with the lower
lip and chin ahead of the upper lip. The intraoral examination
revealed an anterior crossbite with negative overbite and overjet;
50% of upper incisors showing upon smile, with retroclination in
respect to lower incisors; the cant of smile line with canines sticking
out (Figs. 1a–1h); an uneven gingival display during smile in the
anterior region, complicated by an uneven gingival architecture
around upper anterior teeth and the uneven size of left and right
central and lateral maxillary incisors; and moderate maxillary and
mandibular crowding (Figs. 1b and 1e).
Radiographically (Fig. 2a and 2b), the patient showed a moderate
dolichofacial pattern, with deficient and excessive midfacial length
and mandibular body, respectively. All third molars were present.
Fig. 1g
Fig. 1h
Fig. 2a
Fig. 2b
Treatment objectives and planning
This case falls into the category of nonsurgical camouflage
treatment because of the mild skeletal discrepancy and the mild
to moderate space deficiency. Unlocking of the anterior bite
along with conventional Class III mechanics was applied, with
an emphasis on enhancing smile aesthetics and the display of
maxillary anterior teeth.2
The patient was instructed to have all third molars extracted
before bonding, so the retromolar space could be used for full lower
arch distalization, with the help of temporary anchorage devices
(TADs) if needed. Maxillary and mandibular incisor brackets would
be flipped 180 degrees to counteract the side effects of Class III
mechanics, mainly flaring of the maxillary anterior teeth and
retroclination of the lower mandibular anterior teeth.3
Treatment progress
Passive self-ligating braces with 0.0215-by-0.0275-inch slot
dimension (Genius, MEM) were directly bonded from 7–7, and
14 thermally activated nickel titanium wires (Thermal Ultra,
MEM) were inserted, delivering 25 g for 1.5 mm of wire deflection.
Stops were placed on upper and lower wires at midline. Immediate
Class III elastics (2.5-ounce, 3/16-inch, worn full time) ran from the
upper first molar to lower first bicuspids bilaterally. Disarticulation
required light-cure band cement (Bandlock, Reliance Orthodontics)
on the palatal cusp of upper second molars (Figs. 3a–3c).
On the third visit, 4½ months into treatment, 0.018-inch
thermally activated nickel titanium wires (Thermal Ultra) were
engaged in both arches, and two 12-mm TAD microimplants
(Abso-Anchor, Dentos) were placed in the distobuccal area of the
mandibular buccal shelf of the mandibular second molar (Figs. 4a–4c).4
The initial plan was to place the TADs in the retromolar area;
however, nearly five months after the extraction of all third molars
and the start of the fixed appliance therapy, the quality of the bone
was not adequate to ensure initial stability of the TADs.
On the fourth visit, six months into treatment, 0.014-by-0.025-
inch thermally activated nickel titanium wires (Thermal Ultra)
were inserted in both arches, and full lower-arch distalization was
carried out using the buccal shelf TADs.
On the seventh visit, eight months into treatment, 0.018-by-0.025-
inch thermally activated nickel titanium wires (Thermal Ultra) were
engaged on both arches. The force used to connect the TADs to
the lower arch was increased progressively from 100 g per side on
round nickel titanium wires to 200 g per side when in rectangular
nickel titanium wires (Figs. 5a–5c).
On the eighth visit, 10 months into treatment, a 0.019-by-0.025-
inch stainless steel arch form (Europa II Genius) was engaged in the
upper arch, with a figure-eight ligature from 3–3, a tieback from 6 to 3 bilaterally, torque expression on anterior teeth, and flipped
anterior brackets to resist the flaring effect of the heavy Class III
elastics. On the lower arch, a 0.017-by-0.025-inch stainless steel
arch form (Europa II Genius) was engaged, with interproximal
reduction from mandibular canine to canine to harmonize the
contact points and increase the overjet, to allow the negative torque
on upper anterior teeth to upright the incisors into a more aesthetic
position (Figs. 6a–6c). The patient was instructed to wear Class III
elastics (4-ounce, 5/16-inch) at night for the next couple of months
to preserve the bite correction, running from upper 6 to upper 3
down to lower 3 (Figs. 7a and 7b).
Fig. 7a
Fig. 7b
On the 12th visit, 15 months into treatment, an 0.018-by-0.025-
inch thermally activated nickel titanium wire (Thermal Ultra)
and a 0.017-by-0.025-inch stainless steel archwire (Europa II
Genius) were engaged in the upper and lower brackets, respectively.
All four maxillary anterior central and lateral incisor brackets were repositioned for a better smile arc, and interproximal reduction from
lower canine to canine was performed with energy chain under
the brackets to close the spaces with reduced friction. A control
panoramic and cephalometric X-ray (Figs. 8a and 8b) were
taken at this stage before debonding.
Fig. 8a
Fig. 8b
On the 13th visit, 17 months into treatment, upper and lower
fixed appliances were debonded, and a lower 3–3 fixed wire retainer
(Ortho FlexTech, Reliance) was installed. Soft and hard tissue were
contoured, the embrasure touched up and gingiva on upper anterior
teeth trimmed. The patient was supplied with polycarbonate retainers
for both arches to wear at night (Figs. 9a–9h).
Fig. 9d
Fig. 9e
Case discussion
The case was completed in 17 months with 13 visits. The use of
a reduced-slot passive self-ligating bracket system, with slow, light
wire expansion delivering forces around 25–30g, helped achieve
the transverse and antero-posterior correction of the malocclusion,
assisted by immediate light short Class III elastics and posterior
bite disarticulation.
Flipping upper and lower anterior brackets from lateral to lateral
to get opposite torque built in the prescription was an important
factor in controlling the axial inclination of the anterior teeth and
counteracting the side effects of using Class III elastics. It would
have been more efficient to bond upper anterior brackets more
gingivally from the start to achieve a better smile arc and incisor
display. Some upper and lower interproximal reduction was necessary
to harmonize contact points and coordinate the upper and lower
anterior teeth size.5
The application of buccal shelf TADs ensured a full mandibular
dentoalveolar distal retraction and helped optimize the antero-posterior
position of the maxillary anterior teeth, preventing them from
unwanted excessive labial movement, which would have caused
a compromise in the smile dynamics of the patient. Before/after
pairings are Figs. 10 and 11.
Fig. 10a
Fig. 10b
Fig. 11a
Fig. 11b
Conclusion
Camouflage treatment of adult Class III malocclusion has
always been considered to offer suboptimal results because the
unwanted side effects of the mechanics used successfully correct
the underlying dentoskeletal problem but miss the goals regarding
aesthetic outcomes. By using mandibular buccal shelf TADs and
taking advantage of the ability to flip the upper and lower anterior
brackets 180 degrees, control over placement of the maxillary
incisors for the most pleasing aesthetic result can now be achieved.
References
1. Park, Hyo-Sang. “Efficient Use of Microimplants in Orthodontics.” Dentos 2015: Vol. 2, Chapter
4: 206–210.
2. Buitrago, Diego Fernando López, and Saavedra, Claudia Marcela Corral. “Therapeutic Management
of a Pseudo Class III Malocclusion Case Report.” Rev Mex de Orto, 2015: 249.
3. Foster, Chad. “A Protocol for Inverting Upper Incisor Brackets.” Orthodontic Practice, Vol. 12,
Spring 2021: N1.
4. Chang, Chris, Huang, Chi, and Roberts, Eugene W. “3D Cortical Bone Anatomy of the Mandibular
Buccal Shelf: A CBCT Study to Define Sites for Extra-Alveolar Bone Screws To Treat Class III
Malocclusion.” IJOI 41, 2016.
5. Sarver, D. “Enameloplasty and Esthetic Finishing in Orthodontics: Identification and Treatment of
Microesthetic Features In Orthodontics, Part 1.” J Esth Rest Dent, Vol 23 Issue 5: 296–302.
Dr. Bilal Koleilat earned his DDS from St. Joseph University in Beirut in 1993
and a master’s degree in orthodontics in Finland in 1996. He maintains
private practices in Beirut and Dubai, United Arab Emirates. Koleilat has
been teaching since 2002, serving as an assistant professor and the former
postgraduate program director for the Lebanese University Faculty of Dental
Medicine in Beirut. He has lectured in more than 25 countries, with a special
interest in light forces, self-ligation and skeletal anchorage.