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Dental Tribune Middle East & Africa Edition | 6/2016 25 restorative and value. In many cases, when it decided that a tooth has a certain shade, the Hue and the Chroma are communicated to the lab, but never the value and this is where the prob- lemsarise. Very few crowns are accepted if the value is incorrect, while moderate inaccuracies in chroma and hue may go unnoticed. For this reason the shade taking protocol needs to be based on this information be- ing communicated to the lab in the mostaccuratewaypossible. Before the shade is taken conven- tionally or a picture is taken for the same purpose, several factors need tobecontrolled: 1. If patient is wearing bright colored clothing, drape him or her with a neutralcoloredcover. 2. Have patient remove lipstick and othermake-up,aswellaseyewear. 3.Teethmusthavebeencleaned. 4. The shade taking should be done at the beginning of the appoint- ment,sothatteetharemoist(thepa- tient must lick their teeth constantly to keep them moist) and your eyes fresh. 5. The operatory light should be turned off or pointed in another direction. It must not focus on the patient. 6. The room light conditions should have a temperature of 5500-6500° K. (when pictures are taken, these parameters are no longer relevant, because the light of the flash will prevail). 7.Obtainvaluelevelsbysquinting. 8. Women are far less likely to be color blind than men, so it is a good idea to have your assistant assist in shade taking decisions (assuming thattheassistantisawomanandnot colorblind) In Part 1 of this article, the neces- sary equipment and accessories for adequate intraoral pictures was dis- cussed. Please refer to it for the necessary information if you are planning to purchase adequate equipment. Once the patient is ready, place the shade tabs in front of the anterior teeth, before starting the treatment itself. The same applies for pictures withlips.Itisimportanttorepeatthe same protocol intraorally, as well as extraorally, because of the large in- fluence of the reds in shade taking. (Figures7-8) In addition to the points presented before, the following should be con- sidered initially when photographs aretaken:(Figures9-13) 1. Avoid the large reflection areas of the metal parts of the shade guide as theyreducethedetailofthepictures 2. Take pictures using two different shadetabs 3. The surface of the shade tab must be at exactly the same level of the buccal surface of the teeth, as even minor discrepancies can make a tooth look darker or brighter due to thepoweroftheflash) 4. The incisal edge of the tabs should beatroughly1mmdistancefromthe natural teeth, or as close as possible, withouttouchingeachother. 5. Take pictures with and without contrasters. This is especially rele- vant in young teeth with opalescent areasandclearhaloeffects. 6. In cases where an all-ceramic res- toration is planned, the shade of the stump should also be given to the lab, using a special shade guide, such as the natural die material shade guide of the IPS e.max system (Ivo- clarVivadent,Liechtenstein). 7. Consider taking some pictures in black and white. A black and white photographwillhelpshowthevalue of the shade tab in relation to the pa- tient’stooth.(Figure14) Clinicalcase A 27-year-old female patient came to our office unsatisfied with the appearance of her 2 anterior pfm crowns (Figure 15). The value of both crowns clearly did not match the other teeth and her smile line unfor- tunately also showed the discolored cervicalpartoftooth11(Figure16). An overview picture of the stump shade was taken with a reference (Figure 17a). This reference should ideally be the natural die material A - D shade guide (Figure 17d). Both shade guides, the natural die mate- rial guide and the A-D shade guide have some similarities, for exam- ple, as a rule of thumb an ND2 looks quitesimilartoanA2(Figure17b). Obviously, the natural die mate- rial shade guide has shades that are dark, since its purpose is to correlate to artificially discolored stumps and not to recreate natural shades as the A-Dshadeguide(Figures17cand17d). Internal bleaching of the stump was then performed with 35% hydrogen peroxide (Figure 18) in 2 sessions of 20 minutes each. Figure 19 shows the final result after the composite build-up with Excite DSC and Multi- coreflow(IvoclarVivadent,Liechten- stein). An impression was taken and senttothelab. The cast was scanned and an IPS e.max Cad LT block was milled (Figure 20). The appearance of the crowns is always checked with the natural die material stumps in order to get the correct value and chroma (Figures 21 and 22). Finally, contacts and final integration of the crowns were checked in the solid cast (Fig- ure 23, laboratory work done by CDT Volker Brosch, Germany). A retraction cord was placed prior to bonding the crowns (Figure 24). The stumps are etched with phosphoric acid (Figure 25) and Excite DSC was applied (Figure 26). Variolink N (base andcatalyst,translucentshade)were mixed and applied to the crowns (Figure27and28). After4weeksanaturalintegrationof the crowns with the right hue, value, chroma and effects can be seen in Figure29. Figures9and10:Overviewpictureswithdifferent shade tabs. Figures13and14:Coloredandblackandwhitepicture. Figures17a-17d:Thestumpshadeisshowncomparedwithashadetab.Ideallythenaturaldiematerialshade guideshouldbeused.AsanexampleA2lookssimilar toND2. Figure 15: Unhappy patient with unsatisfactory crowns. Figure18:Discoloredstump. Figure 20: IPS e.max CAD crowns after milling with the MC XL (Sirona) unit. The copings need to be crystalized in order to get thefinalshade. Figure22:Finalappearanceof thecrowns placed on top of the natural die material stumps, which has the same shade than the dentin-composite stumps in the pa- tient'smouth. Figure 21: Layering steps. The shade is compared with the natural die material stumps. Figure 23: Proximal contact and integra- tioncontrolin themodel. Figure 24: A retraction cord was placed prioretching Figure 16:The smile is high, situation that makes the metalmarginof thePFMcrownobvious. Figure 19: Situation after internal bleaching and compositebuildup. Figures11and12:Close-uppictureswithdifferent shade tabs. Figure25:Etchingwithphosphoricacid. Figure29:Finalresult after2weeks. Figure 30: The value of the restorations match theonefrom thenatural teeth. Figure31:Naturalintegratedcrowns. Figure26:BondingwithExciteDSC. Figures27and28:MixingandapplicationofVariolinkN(IvoclarVivadent). Acknowledgements The author would like to thank CDT Juergen Seger and Volker Brosch for their valuable technical work pre- sentedinthisarticle. ◊Page24 Dr. Eduardo Mahn, Chile, has graduated from the University of Chile in 2004. He received the German DDS, one year later. The New York Univer- sity College of Den- tistry certified him as Implantologist in 2007. In 2008, he published his doctorate thesis in 2008 titled “Osseointegration of zirconia implants, an in vivo study” and got hisdoctoratedegreein2010fromthe UniversityofDüsseldorf,Germany.