GAP Australasian-Dentist-Mar Apr 2019

Category 68 AustrAlAsiAn Dentist lInICal the majority of commercially available restorative materials commonly exhibit a significant divergent in refractive index and fluorescence from natural tooth substrates; making layering of composite resin difficult to master. By contrast, Aura’s near identical fluorescence and refractive index mean that as layers become thicker and more complex, the translucency and value of the restorative material remain identical to natural teeth. Given the optical characteristics of the tooth structure to be replaced, a layered approach was chosen and mimicking natural tooth, dentine shades with higher chromaticity were used in the deeper areas, and this in turn also allowed for the complete masking of the stainless-steel post with no requirement for any intensifiers or masking material. More superficial layers of dentine were built up with dentine shades of lower chroma, and the final layering was performed with Aura enamel e1 shade which is a high value, lower translucency enamel composite which mimics younger tooth shades. it is important to note that the refractive index and the florescence of the Aura enamel shade e1 closely mimics the natural tooth structure so much so that conventional feathering of margins was not necessary or a bulk build up of this material. As the images illustrate, butt joints were used in order to preserve the tooth structure and yet despite the abrupt change in contour, the chameleon effect of Aura was so superior that the material blended in seamlessly with the underlying and adjacent tooth structure. Although the dentine shades are built for strength and stiffness, utilising a form of nano-hybrid technology, the enamel shades are produced as a microfill allowing for superior polishability and surface luster. the patient was seen for a six month and a one year recall with no re-contouring required and very minimal polishing to renew the surface luster. u About the author Dr Angelo Lazaris earned his Bachelor of Dental Surgery degree with Honours in 1991 from the University of Sydney. Since graduating, he has completed a number of post-graduate courses and educational programmes, both in Australia and overseas, furthering his knowledge and experience in the fields of Cosmetic Dentistry, Dental Implants and Complex Restorative Dentistry, which are areas of special interest for his practice. In 2014, Dr Lazaris graduated from the highly prestigious Kings College London Dental School’s Post Graduate Masters in Aesthetic Dentistry program; making him one of the first dentists in Australia with this formal qualification. Dr Lazaris teaches and lectures extensively on aesthetic and contemporary restorative dentistry nationally and abroad. He holds honorary senior lecturing tenures at the University of Sydney and Kings College London. Figure 2b: Digital Shade analysis utilising colour samples and imaging software. Figure 3: Stratified build-up of direct composite resin with highly chromatic dentine shades used for deep layers, and higher value composite used to replace superficial dentine. Figure 4: Finishing and polishing with scalpel and finishing burs. Figure 5: Polishing with graduated rubber cups, goat’s hair disc and leather chamoix. Figure 6a & b: Final result. High contrast image demonstrating optical integration with natural tooth structure. Figure 6c: Final result.