_Dentalmaterialsandclinicalprocedureshavechangeddramaticallyinthelastdecades.Probablythemajoradvancesthathaveoccurredduringthelasttwodecadeshavebeeninthe
fields of implantology and adhesive dentistry, butthe main
revolution is the development of
digitaldentistry.Althoughthesechangeshavecertainlymadediagnosticsandcertainprocedureseasier,
thebasics,suchasfunctionandthebiological
aspects,remainessential.Atthesametime,we have expe rienced major
improvements in
ceramicsandcomposites,helpingustofulfilourpatientsaesthetic
demands. A basic prerequisite for these indications is an
in-depthunderstandingofthefacialanddentalaesthetic parameters. The
clinician needs to under-stand the challenges that each clinical
case presentsand has to be able to develop an appropriate
treat-ment plan that approaches the case from a multi-disciplinary
perspective. Tooth proportions need tobe considered in relation to
gingival aesthetics andin relation to the facial appearance. It is
pointless tomakethemostbeautifuldirectveneerifthe contours or the
texture do not match that of the adjacent teeth or the gingival
zeniths are clearly notsymmetricandvisible.Asanexample,ifweadd a
tilted occlusal plane or a maxillary tooth midlineshift in relation
to the facial midline, the results canbe frustrating.Another
important aspect is the proper
analysisofthepatientssmileanddisplay(Figs.1&2). When
photographs are taken, people tend to be shy, especially at the
beginning and even more so if theperson taking the photographs is
not a professionalphotographer and the setting is a dental
practice.Figure 3 shows the intra-oral view, where,
besidestheobviousdiastemaandthehypomineralisedI special _ di gi
talsmi l e desi gn06 ICAD/CAM4_2014Designing real smiles with
digital toolsAuthors_Drs Eduardo Mahn, Gustavo Mahn, Carlos Cceres,
Luis Bustos, Chile & Christian Coachman, BrazilFig. 1 Fig.
2Fig. 3CAD0414_06-10_Mahn14.11.1413:34Seite 1I07special _ di gi
talsmi l e desi gn ICAD/CAM4_2014 areas of both central incisors,
the major discolouredareasofbothmandibularlateralincisors,whichwere
certainly in need of some sort of treatment, are apparent. It is
important to try to make a
videowhileconversingwiththepatientaboutnormaldaily issues to avoid
overlooking aspects that needto be considered in the treatment
plan. The conver-sation will relax the patient and evoke natural
smilesandlaughsinresponsetosomethinghumorous or silly that we might
say. Figure 4 shows the dif -ferences between the social smile we
achieved withour traditional photographs (Figs. 1 & 2) and
theFig. 5Fig. 4Fig. 13 Fig. 11Fig. 10b Fig. 9Fig. 8 Fig. 6 Fig.
7Fig. 10aFig. 12CAD0414_06-10_Mahn14.11.1413:34Seite 208 II special
_ di gi talsmi l e desi gnspontaneoussmile,whichwascapturedduring
dynamic recording. In this particular clinical case,had we based
our treatment plan on the social smilephotograph, we would have
failed to visualise thedisplay of the mandibular incisors, which
showedunpleasant stains. The next step was to analyse the patient
from thefacial perspective based on the details of her
teeth.Thedigitalsmiledesign(DSD)conceptdiagnosesaesthetic problems
from a facial perspective and,based on a simplified digital
analysis of a few pho-tographs, proposes treatment options and
assistswith communication between the various special-ists in the
team. The first step is to draw a horizontal and a ver ticalline.
The photograph is centred, moved and
rotateduntilthebi-pupillarylineishorizontal.Thefacialmidline is
subsequently ascertained. Then the samelines are superimposed on to
a similar photograph,whichhasalsobeencentred,butthistimetakenwith
lip retractors in place (Figs. 5ac). The
samephotographsarethenmagnifiedandanalysed (Figs. 6 & 7). The
upper lip line is re -created and then superimposed on tothe
photograph taken with lip retrac-tors in place as reference of its
position(Figs. 8 & 9). Then the tooth proportionsare measured
and their ideal contoursare drawn (Figs. 9 & 10a). The
isolatedsituationcanbeseeninFigure10b. A photograph taken from the
12 oclockposition is used for the analysis of thelabio-palatal
position of the teeth andsuperimposed on to the analysis
donepreviously (Fig. 11). Oncetheclinicianisclearabout the
treatment possibilities and limita-tions, a digitally designed
mock-up can be created.Thisprocedurereduceschairtimedramatically
and increases patient acceptance. Owing to easilyaccessible
software such as Microsoft
PowerPointandKeynote,theseeffectsareeasilyandquickly created by
anyone with minimal training.
Recently,newsoftwarehasbeenreleasedthatsimplifies the procedure
even more, DSD software for
iPads(www.digitalsmiledesign.com).Theprocedureisbased on
overlapping certain areas of the teeth inthe manner previously
described. The result can beseen in detail in Figure 12 and the
display in Figure13. A comparison from the facial perspective
be-tweenthepreoperativesituation,thetraditionalmock-up and the
digital mock-up can be seen in Figure 14. Traditional indirect
mock-ups are madefrom a previously created wax-up from the
labora-tory. First, an impression is taken and a stone cast is then
fabricated. Afterwards, the technician waxesthe necessary teeth
depending on the instructionsgiven by the clinician. The next step
is taking an impression from thatwax-up. The excess is removed and
a flowable self-ordual-curingcompositematerial(usually bis-acrylic
based) is applied tothe silicone guide and then placed inthe
patients mouth. After a few min-utes,theexcessisremovedandthe
patient is able to see the changes
andtheclinicianisabletoevaluatethe proposal directly in the mouth.
Gener-ally, photographs are taken of the newsituation and analysed.
The option of
adigitalmock-upismuchsimpler.Oncethefinalformshavebeencre-ated,aphotographissuperimposed
on to them, and the texture of the newteeth is created. As seen in
Figure 14,the results of the traditional and
thedigitalmethodsaresimilaranditisdifficult to differentiate
between them.CAD/CAM4_2014Fig. 15Fig.
14CAD0414_06-10_Mahn14.11.1413:34Seite 3I09special _ di gi talsmi l
e desi gn ICAD/CAM4_2014Theprotocolisbasedonphotographsand videos
that are taken during the first appointment.The analysis is
performed, and eventually the case isdiscussed with the team if
necessary. Once the pres-entation is ready, the treatment plan is
presented in a visually attractive way to the patient (Fig.
15).Finally, whether to use ceramic or composite re sto ra -tive
materials is considered depending on differentfactors. Our
philosophy is based on the
minimallyinvasiveconcept.Aslongaswecanprovidethe
patientwiththesameaesthetics,durabilityand predictability of
ceramics, we will select composites.In cases in which many teeth
are involved, multiplediastemas are present or occlusal imbalances
mayjeopardise a successful outcome and major changesneed to be
made, our choice leans towards ceramics.Whatever approach is
chosen, it is of paramount im-portance for the clinician to
understand theceramicFig. 22Fig. 21 Fig. 20Fig. 19 Fig. 18Fig. 17
Fig. 16CAD0414_06-10_Mahn14.11.1413:34Seite 410 II special _ di gi
talsmi l e desi gnand/or composite system he or she is using. In
thisparticularclinicalcase,theceramicsystemused was IPS e.max Press
and the composite system wasIPS Empress Direct (both Ivoclar
Vivadent) becauseof its simple layering concept, its
natural-lookingshades and long-lasting gloss. The
correspondencesbetweentheshadesofbothsystemsmakethemeasier to
combine.Once the treatment plan has been accepted bythe patient,
the treatment begins with
preparationanddemarcationinordertobeasconservative as possible
(Fig. 16). Figure 17 shows the detail of
thehypomineralisedareasofthemandibularlateral
incisors.Theareaswereexcavatedwithared-coloured bur (Komet Dental)
and etched with phos-phoric acid. ExciTE F (Ivoclar Vivadent) was
used as a bonding agent, and IPS Empress Direct Dentin A1and Enamel
A1 were placed using a novel instru-ment called OptraSculpt Pad
(Ivoclar Vivadent).The maxillary teeth were prepared and
impres-sions taken. Figure 20 shows the six veneers fabri-cated by
master dental technician Victor
Romero(Santiago,Chile).Thentheyweretried-inwitha
speciallydesignedglycerine-basedpaste,com -ponents of the Variolink
Esthetic cementation kit(Ivoclar Vivadent). Figure 21 shows how
dramaticthe change in value can be with this type of cement.This
procedure is especially helpful when one or twoveneers are seated,
and the value needs to be slightlycorrected in order to match them
to the adjacentteeth. The veneers were then bonded and the
finalresult can be seen in Figure 22, where the preopera-tive
situation is shown against the similar resultsachieved with the
digital mock-up compared withthe final outcome. Figures 23 and 24
show the inte-gration of the six maxillary ceramic veneers and
thetwo direct composite restorations performed on themandibular
lateral incisors at the three-month fol-low-up. All this work was
integrated from the facialperspective, as seen in Figure 25. The
satisfied andspontaneous patient can be observed in Figure
26._CAD/CAM4_2014Dr Eduardo Mahn, DDS, DMD, PhD, is a lecturer at
the Universidad de los Andes in Santiago, Chile.Dr Gustavo Mahn,
DDS, is a lecturer at the university Finis Terrae in Santiago,
Chile.Dr Carlos Cceres, DDS, is a lecturer at Universidad del
Desarrollo in Concepcin, Chile.Dr Luis Bustos, DDS, is a lecturer
at Universidad del Desarrollo in Concepcin, Chile.Dr Christian
Coachman, DMD, MDT, is in privatepractice in So Paulo in
Brazil._contact: Dr Eduardo Mahn, [email protected]/CAM _about
the authorsFig. 26 Fig. 25Fig. 24 Fig.
23CAD0414_06-10_Mahn14.11.1413:34Seite 5
