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CE article _ mastering occlusal function I anatomies were available, and these patterns had to be manipulated greatly by the doctor to fit the clinical situation. This made for a longer design time and, most importantly, made the restoration appear more natural.1 Today, there are more advanced mathematical calculations for dental anatomy. Modern tooth-modeling software uses a data- base detailing the measurements of several thou- sand naturally occurring tooth samples. Common structures such as cusp tips, cusp slopes, marginal ridgesandfissuresgivetheblueprintforcomputer determination of the “average tooth.” The differ- encesbetweenthisaveragetoothandthescanned referenced teeth make up the core for the mathe- matical calculation, much like with facial recogni- tion software used by government intelligence agencies. Analysis reveals that only 20 data loca- tion points are necessary to describe 83 per cent of the variability in naturally occurring tooth sur- faces.2,3,4,5 Thismathematicalcalculationfortooth morphology therefore predicts the virgin state of the tooth. It has been shown to have a digitally proposed surface within 156 µ of the original surface.1 Be- cause the described process obtains its results through data derived from naturally occurring teeth,themethodisreferredtoas“Biogenerictooth modeling.”2, 3 This mathematical calculation of dental ana- tomystartswithdesignatingthetoothnumbertobe designed. This establishes which database of dental anatomies that it will use to determine the calcula- tions. In other words, the true tooth number needs tobeselectedforthecalculation,oradifferenttooth number anatomy will be generated (Fig. 1). The next step for the calculation is to show the computeratooththatitcanuseforguidanceonthe proposed design. This can be done a couple of ways. Primarily, a tooth within the prepared quadrant (not the prepared tooth) will be analyzed automa- tically by the computer, and is typically the distal neighbor of the prepared tooth (Fig. 2). If the clini- cian knows of a better tooth to reference, this can easily be selected within the prepared arch, within another area of the dentition, or even off a model. This referenced dataset will trigger the computer to search the entire database, which may contain hundreds of different virgin anatomies for that particular tooth number.2, 3, 4 Fig. 5_Digitally scanned teeth are organized into specific libraries. Fig. 6_During imaging, the position of the upper and lower teeth is not correct and space is seen. Fig. 7_The dentist sees the error and instructs the patient to close properly. Figs. 8 & 9_The buccal bite images are used to articulate the upper and lower models. Fig. 10_The digital articulation is completed. I 07cosmeticdentistry 4_2012 Fig. 8 Fig. 9 Fig. 5 Fig. 6 Fig. 10 Fig. 7