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Accreditation Essentials
Considering All Parameters
with Porcelain Veneers
Minimal Tooth Reduction with a Maximum Chance of Success
Vin Vu, DDS, AAACD
Key Words: Accreditation Case Type I, minimal preparation,
porcelain veneers, direct and indirect veneers
Introduction
There are many factors involved in a beautiful smile. The most basic
elements of a nice smile are: no spaces or missing teeth, the teeth
have to be relatively aligned, and they have to be relatively white
within the esthetic zone.1 As cosmetic dentists, we need to consider
other parameters that will transform a nice smile into a great smile.
Those parameters include the smile line, midline, axial inclinations,
embrasures, proportions, central dominance, emergence profile,
tooth anatomy, buccal corridor, and gingival architecture.2
AACD Accreditation Case Type I requires us to evaluate, diagnose,
and use current smile design principles for success.
Patient’s Chief Complaints and History
Figure 1: Preoperative image. The patient had a nice smile, but
she wanted a beautiful one.
24 Spring 2014 • Volume 30 • Number 1
Amy, a healthy 29 year old, had an unremarkable medical history.
Her dental history consisted of posterior restorations and routine
continuing care.
Amy had been a dental assistant in our office since 2004 and
had seen firsthand what today’s cosmetic dentistry can offer and the
procedures involved. From the simplest to the most complex case,
the change in a person’s appearance can be profound. Recently,
Amy’s role changed from clinical team member to front-office team
member. She was no longer behind a mask all day; instead, she was
greeting, meeting, and serving patients. Her teeth and smile had
become more important to her and she wanted to transform her nice
smile into a beautiful one. Her comment was, “I don’t like the gaps
between my teeth, the spacing, and the unevenness of my teeth. I
really want to have a beautiful smile” (Fig 1).
Vu
Diagnosis and Treatment Plan
The goal of the treatment plan was to address the following:
•spacing between ##10-12
•asymmetry in length and shape of contralateral teeth
•incisal embrasure form (Figs 2a-4).
Amy wanted long-lasting restorations that looked natural without
removing tooth structure. One of the biggest challenges was deciding
whether to restore her teeth with direct or indirect restorations. A case
could be made for either treatment option. Ultimately, the decision was
made to restore ##6-11 with porcelain veneers for their stain resistance
and maintenance-free properties.3 Tooth #12 was rotated with the mesial
surface to the facial, making the incisal embrasure space excessive. We
planned not to remove any tooth structure and only add composite resin
directly to fill in the excessive space. Remember, this was a smile design
case and many times, one must consider more than just the front six
teeth.4
As cosmetic dentists, we need
to consider other parameters
that will transform a nice
smile into a great smile.
Figures 2a-2c: Preoperative 1:2 full-smile view. These images show a hint of excessive incisal embrasure form between the laterals and
canines, and asymmetry in length. Yet the color/value of the teeth is relatively nice and there are minimal spacing issues.
Figures 3a-3c: Preoperative retracted 1:2 view. Notice the spacing and excessive incisal embrasure form between ##10-12, and the asymmetry
in length and shape of contralateral teeth. However, gingival symmetry and appropriate architecture are present.
Journal of Cosmetic Dentistry
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Accreditation Essentials
Treatment Description
Preparation
Teeth ##6-11 were minimally prepared facially and
interproximally to give the ceramist a defined finish
line (diamond bur KS1 012, Brasseler USA; Savannah,
GA). Incisal preparation consisted of a very minimal
(0.3 to 0.5 mm) reduction (Fig 5). The preparations
were impressed with Affinis heavy and light body
(Coltene/Whaledent; Cuyahoga Falls, OH).
Photographs were taken of the underlying tooth
structure along with preparation shade tabs. The desired degree of characterization and decalcification,
surface texture, anatomy, translucency; and the hue,
chroma, and value were also communicated through
photographic documentation. The preoperative central incisor dimensions were 8.3 mm in width by 9
mm in length, or 92% width-to-length ratio. The
length was increased to 10.4 mm to give a more ideal
ratio of 79.8%.
We did not make provisionals for the prepared
teeth due to minimal tooth reduction. In addition, the
patient did not have any tooth sensitivity. The veneers
were fabricated from Ceramco Color Logic (Dentsply;
York, PA) feldspathic porcelain using a platinum foil
technique.
Tooth #12’s enamel surface received micro-abrasion preparation with a KCP-1000 Whisper Jet (American Dental Airsonic Technologies; Corpus Christi,
TX). The micro-abrasion particle of 27-µ alpha alumina was used at 80 psi.
Figure 4: Preoperative 1:2 occlusal view. The teeth are in the relatively correct
position.
Etching, Bonding, and Layering
Teeth ##6-11 were pumiced to clean the surfaces of
any debris. The surface was thoroughly rinsed for 30
seconds and lightly dried. Retraction cords (000 size,
Ultradent Products; South Jordan, UT) were placed
facially and interproximally to expose all margins.
Each tooth was prepared for bonding by acid-etching
(37% phosphoric acid, Pulpdent; Watertown, MA) the
prepared surfaces for 20 seconds, rinsing thoroughly,
and drying lightly. Several coats of Prime and Bond
NT bonding agent (Dentsply Caulk; Milford, DE) were
applied with a microbrush (Microbrush International;
Grafton, WI). The surfaces were lightly air-dried, and
light-cured for 20 seconds.
The restorations were etched with 9% buffered
hydrofluoric acid (Ultradent) for two minutes, then
rinsed and dried. Tokuso Ceramic Primer saline
(Tokuyama Dental America; Encinitas, CA) was applied to the restoration for 10 seconds and then lightly
26 Spring 2014 • Volume 30 • Number 1
Figure 5: Preparation was kept to a minimum.
dried. A translucent shade of Calibra resin cement (Dentsply Caulk) was
used to bond the veneers. Each surface was light-cured for 40 seconds.
Excess cement was removed. The occlusion was adjusted as necessary to
achieve centric contacts and adequate anterior guidance. The adjusted areas were then polished with CeramiPro Dialite W16D (Brasseler USA).
Tooth #12 was etched (37% phosphoric acid, Pulpdent) for 20 seconds. The surface was rinsed with an air-water mixture for 20 seconds
then lightly dried. Two to three coats of Prime and Bond NT bonding
agent were applied with a microbrush. The surface was lightly air-dried
for 10 seconds and light-cured for 20 seconds.
Estelite Omega composite resin (Tokuyama Dental America) was used
to restore tooth #12. Based upon the manufacturer’s material description,
the composite resin is composed of silica-zirconia filler and composite
Vu
filler (82% by weight, 71% by volume), with an average particle size of 200 nm (range of 100 to 300 nm).
The monomer matrix is made of bisphenol A di (2-hydroxypropoxy), Bis-GMA and TEGDMA.
The first step was the building of a thin lingual shelf
layer using the putty matrix technique with milky
white shade. Next, Dentin A1 was placed as a dentin
layer to opaque and block out the tooth-to-restoration
interface. A translucent shade was used for the incisal, mesial, and distal line angles. Enamel shade B1
followed on the gingival and body to full contour.
The interproximal contacts were formed by using the
“pull through” technique5 of the mylar strips. Finally,
a milky white shade was used at the incisal one-third
to bring it to full contour.
Contouring, Finishing, and Polishing
Coarse and medium Sof-Lex discs (3M ESPE; St. Paul,
MN), Epitex finishing strips (GC America; Alsip, IL),
and fine diamond burs (135F.31.014 and 8889.31.009,
Brasseler USA) were used to contour the outline form
and primary and secondary anatomy. The occlusal adjustments were made with a football-shaped diamond
bur (8379.31.018, Brasseler USA) and Enhance finishing points (Dentsply Caulk). Tertiary anatomy was created with Brasseler’s fine diamond bur (8392.31.016).
Fine and super-fine Sof-Lex discs and Epitex finishing strips were used for final polishing. Enamelize polishing paste (Cosmedent; Chicago, IL) was used with
a blue felt buffing disc (Cosmedent) to impart a glossy
sheen finish.
Discussion
One issue we had with this case was the fracturing
of a veneer during the cementation process (Fig 6).
Too much pressure was applied to seat the veneer into
Figure 6: It does not take much pressure to fracture a 0.3-mm thick feldspathic
porcelain veneer.
place and it fractured. The facial thickness of these veneers ranges from
0.3 mm to 0.5 mm. I think we all have to go through this to develop a
sense of how much pressure to apply for the seating of these very thin
porcelain veneers.
Summary
Accreditation Case Type I is all about smile design, patient selection, and
communication with the dental laboratory. If one selects a patient with
teeth that are relatively level and aligned, have minimal spacing issues,
need minimal color change, and have healthy gingival tissue in an appropriate architecture, then the chances of success increase. In this particular
case, the patient had a relatively nice smile from the beginning. With
conservative treatment (minimal preparation) and the use of a direct restoration alongside the porcelain veneers, Amy’s smile, confidence, and
self-image were all enhanced (Figs 7a-10).
Figures 7a-7c: Postoperative retracted 1:2 views. The treatment goals—improved symmetry and proportion, and proper incisal embrasures—
were met.
Journal of Cosmetic Dentistry
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Accreditation Essentials
Figure 8: Postoperative 1:2 view. The incisal edges follow the
curvature of the lower lip.
Figure 9: Postoperative 1:1 view. The increased length on the
centrals gave a width-to-length ratio of 79.8% (compared to 92%
preoperative).
References
1. Morley J, Eubank J. Macroesthetic elements of smile design. J Am
Dent Assoc. 2001 Jan;132(1):39-45.
2. American Academy of Cosmetic Dentistry (AACD). Diagnosis
and treatment evaluation in cosmetic dentistry: a guide to Accreditation criteria. Madison (WI): AACD; 2001.
3. Shillingburg HT, Sumiya H, Whitsett LD, Jacobi R, Brackett SE.
Fundamentals of fixed prosthodontics. 3rd ed. Hanover Park
(IL): Quintessence Pub.; 1997.
4. American Academy of Cosmetic Dentistry (AACD). Introductory
guide to Accreditation. Madison (WI): AACD; 2012.
5.Willhite C. Diastema closure with freehand composite:
controlling emergence contour. Quintessence Int. 2005
Feb;36(2):138-40.
jCD
Figure 10: Postoperative portrait. Amy now greets everyone in our
office with a beautiful, confident smile.
Accreditation Case Type I is all about
smile design, patient selection,
and communication with the dental
laboratory.
28 Spring 2014 • Volume 30 • Number 1
Dr. Vu maintains a practice in Oshkosh, Wisconsin.
Disclosure: The author did not report any disclosures.
Accreditation Essentials
Examiners’ Commentary
Truly a Smile Design Case
Clinical Case Type I: Six or More Indirect
Anterior Restorations
James H. Peyton, DDS, FAACD
This case creates the illusion
from the frontal views
that all the contours and
proportions of the teeth are
correct.
A
ccreditation Case Type I is truly a smile design case. The final restorations all need to look proportional and must enhance the patient’s smile. The dentist is responsible for ensuring the gingival
health is ideal, the soft tissue is even and symmetrical, the teeth are in
alignment, the occlusion is correct, all the appropriate specialty referrals
have been made, and everything is planned in advance of treatment. Then
Case Type I becomes a “marriage” between the laboratory technician and
the dentist to create a lifelike, natural smile that meets the Accreditation
standard of excellence. In this case, the final result was worthy of Accreditation.
As with all Accreditation cases, this case was not perfect. Some of the
examiners’ comments were as follows:
•
Criterion 42: Is the labial anatomy (primary, secondary, and tertiary)
appropriate? Are there three planes for the labial contour of the central incisor?
Facial surface of the canines are slightly convex.
•
Criterion 61: Is margin placement and design appropriate? Are the
margins visible? Visible margins at distal #9, mesial #7, #10, and facial #11.
•
Criterion 72: Is gingival architecture appropriate (in all views) and
in harmony with smile design? Papilla blunted between #9 and #10.
•
Criterion 86: Is the cervical/incisal tooth length symmetrical from
right to left? Tooth #9 is higher than tooth #8.
When preparing the veneers, the mesial facial margin is often the
most difficult to cover; do not forget to prepare into the “interproximal
elbow.” This will eliminate the visible, dark margin. In evaluating this
30 Spring 2014 • Volume 30 • Number 1
Peyton/Vu
Figure 1: Right lateral 1:1 view shows widened cervical contour of #6
and #7.
case, the smile looks great from all the frontal views.
However, as this is a minimally prepared case, the
side views (both right and left) show that the canines
and laterals (#6, #7, #10, and #11) look a little bulky
(Figs 1 & 2). This probably could have been solved
with the necessary tooth reduction, pre-restorative orthodontics (##10-12 area), crown lengthening at #11,
and narrowing some of the cervical contour of #6, #7,
#10, and #11. This case creates the illusion from the
frontal views that all the contours and proportions of
the teeth are correct. When the patient looks in the
mirror, the teeth look normal and well proportioned.
Sometimes we need to create a little “magic,” and Dr.
Vu did just that!
Figure 2: Left lateral 1:1 view depicts a short crown length for #11 and
wide space resulting in #10 and #11 appearing wide and bulky.
When the patient looks in the
mirror, the teeth look normal and
well proportioned. Sometimes
we need to create a little magic
and Dr. Vu did just that!
Dr. Peyton is an AACD Accredited Fellow and has been an AACD Accreditation Examiner since 2000.
A part-time instructor at the UCLA School of Dentistry, he practices in Bakersfield, California.
Disclosure: The author did not report any disclosures.
Journal of Cosmetic Dentistry
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