Dental Tribune United Kingdom Edition

July 11-17, 201114 Cosmetic Tribune United Kingdom Edition V enus Diamond: The diamond class of na- nocomposites Aesthetics play a major role in dentistry. Today it is no longer enough if the anterior region appears aesthetic. Aesthetics in the posterior region are now considered just as important as in the anterior region and in addition to function, durability and stability this is one of the basic criteria that a restoration must fulfil. Posterior restorations can be easily and durably built up directly using composite without having to dispense with the reconstruction of an ana-tomical surface and, consequently, physio-logical function. Though resin-based com- posites have been used for the restoration of posterior teeth for decades, they were often subject to compromises. In- creased patient demands for natural restorations combined with the public debate regard- ing amalgam and the associ- ated health risks as well as the aim of dentists to treat patients as minimally invasive as possi- ble have greatly accelerated the development of composites in the past ten years. As a re-sult, composites have become an indispensible material in con- servative dentistry both in the anterior and posterior regions. The possibilities for tooth conservation have been greatly extended in the literal sense of conservation with the estab- lishment of minimally invasive adhesive techniques and can no longer be compared with the preparation forms of the amalgam era. In the past com- posites were developed as uni- versal composites or specialist composites for the anterior or posterior region. The spectrum of organic and inorganic com- ponents used is just as diverse as the number of composites available. Each of these compo- nents influences the handling properties and clinical behav- iour. These different material classes also allow direct com- posite restorations to be used successfully in the masticatory loadbearing posterior region. However, there were prob- lems in the posterior region that were attributed to the use of composite materials in both clinical studies and as a re- sult of practical experience. The problems were mainly in the form of increased central and lateral occlusal abrasions, marginal gap formations, dis- coloration of the margins and restoration material, marked polymerisation shrinkage and associated stresses as well as postoperative sensitivity. For these reasons the development companies increased research into solutions to minimise or even eliminate these problems. This aim was achieved with the introduction of a new mate- rial class of aesthetic composite materials that also incorporate excellent physical properties. These composites contain new filler particles and were modi- fied in the composite base. They also exhibit improved adaptation, enhanced viscosity and natural shade behaviour. The filler particles were also placed in the nano range, a spectrum which is used to describe functional materials and structures in the range be- tween 0.1nm and 100nm, and distributed homogeneously in the base. These nanofiller com- posites are a new, separate cat- egory of composite materials and are available both as uni- versal composites and as spe- cial composites, such as flowa- bles. Composites modified us- ing nanotechnology provide various advantages compared with conventional universal composites. These include re- duced shrinkage and shrinkage stresses, improved mechanical properties and natural opti- cal behaviour. In vitro studies also verify that the abrasion re- sistance of nanocomposites is comparable or even superior to that of microfiller or microhy- brid composites. The mechanical and physi- cal parameters do not play a sig- nificant role for patients. When patients decide to have an ad- hesive composite restoration, they assume they will receive a Venus Diamond - The diamond class Heinrich Middelmann presents a case report ‘Composites have become an indispensible material in conservative dentistry both in the anterior and posterior regions’ Fig.1: The initial situation at tooth 25 shows an existing mesio-occlusal compos-ite restoration. An X-ray was also taken and indicated distal caries. Fig.2: The carious lesion could be seen after removal of the old restoration and extension of the preparation distally. Fig.3. It was not possible to retain the dis-tal marginal ridge during excavation. The finished preparation provided a very good direct MOD cavity for an adhesive restora-tion. Fig.4: Adhesive restoration in the etch-and-rinse technique using a rubber dam: applica- tion of iBOND Etch 35 beginning at the enamel (30s), then at the dentine (15s).