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09Dental Tribune Nordic Edition | 3/2015 TRENDS&APPLICATIONS siderable further development of ORMOCER-based composites for this range of application. However, theuseofORMOCERsisnotlimited to dental restoratives. These ma- terials have been successfully em- ployed for years in fields such as electronics,microsystemstechnol- ogy, plastic refining, preservation, anticorrosion coatings, functional coatings for glass surfaces, and highlyresistant,scratch-proofpro- tective coatings.39–41 ORMOCER-based dental restora- tive composites are currently avail- able from two dental companies, VOCO (Admira product range) and DENTSPLY (Ceram·X). In the dental ORMOCER products to date, ad- ditional methacrylates were added to the pure ORMOCER chemistry (aswellasinitiators,stabilisers,pig- ments and inorganic fillers) in or- dertoimproveworkability.42 There- fore, it is more accurate to refer to ORMOCER-based composites. According to the manufacturer, the new bulk-fill ORMOCER Admira Fusion x-tra (VOCO), launched in 2015, no longer contains any con- ventional monomers in addition to the ORMOCERs in the matrix. It features a nano-hybrid filler technology with an inorganic filler content of 84 per cent by weight. It is available in a universal shade and displays polymerisation shrink- age of just 1.2 per cent by volume and consequently low shrinkage stress. Admira Fusion x-tra can be applied in layers of up to 4 mm, witheachincrementbeingcuredin 20 seconds (curing light intensity of > 800 mW/cm2 ). The malleable consistencyandtheothermaterial properties of Admira Fusion x-tra allow the dentist to restore cavities using the bulk technique with a single material; an occlusal cover- ing layer with an additional com- posite—as required when flowable bulk composites are used—is no longer necessary. Clinical case A 47-year-old patient presented at our clinic requesting the grad- ual replacement of his remaining amalgam fillings with tooth- coloured restorations. In the first treatment session, we replaced the old amalgam filling in tooth #46 (Fig. 1). The tooth was immediately responsive to the cold test and the percussion test too was normal. Having been informed of the pos- sible treatment alternatives and their costs, the patient elected to have a composite restoration with Admira Fusion x-tra using the bulk-fill technique. Treatment started with thor- ough cleaning of the tooth with a fluoride-free prophylaxis paste and a rubber cup to remove ex- ternal deposits. As Admira Fusion x-traisonlyavailableinauniversal shade, there is no need for detailed determination of the tooth shade. Afteradministrationoflocalanaes- thetic, the amalgam was carefully removed from the tooth (Fig. 2). After excavation, the cavity was finished with a fine-grit diamond burandarubberdamwasplacedto isolatethetooth (Fig.3).Therubber dam separates the operating site from the oral cavity, facilitates clean and effective working, and guarantees that the working area remains free of contaminating substances, such as blood, sulcular fluid and saliva. Contamination of the enamel and dentine would resultinconsiderablypooreradhe- sion of the composite to the dental hard tissue and would endanger the optimal marginal integrity of the restoration for long-term suc- cess. Additionally, the rubber dam protectsthepatientfromirritating substances, such as the adhesive product. The rubber dam is thus an essential aid in ensuring quality and facilitating work in the adhe- sive technique. The minimal effort required in applying the rubber dam is compensated for by avoid- ingthechangingofcottonrollsand the patient’s requests for rinsing. The cavity was then demarcated with a sectional matrix made of metal (Fig. 4). The universal adhe- sive Futurabond M+ (VOCO) was chosen for the adhesive pretreat- ment of the dental hard tissue. Futurabond M+ is a modern one- bottle adhesive compatible with all conditioning techniques: the self-etch technique and the phos- phoric acid-based conditioning techniques (selective enamel etch- ingorcompleteetch-and-rinsepre- treatment of enamel and dentine). In this case, we chose the selective enamel etching technique, apply- ing 35 % phosphoric acid (Vococid, VOCO) along the enamel margins and allowing it to work for 30 sec- onds (Fig. 5). The acid was then rinsed off for 20 seconds with a compressed air and water jet, and excess water carefully removed from the cavity with compressed air (Fig. 6). Figure 7 shows the ap- plication of a generous amount of Futurabond M+ to the enamel and dentine with a micro-brush. The adhesive was thoroughly rubbed into the dental hard tissue with the applicator for 20 seconds. The solvent was then carefully evapo- rated with dry, oil-free compressed air (Fig. 8) and the bonding agent light cured for 10 seconds (Fig. 9). The result was a shiny cavity sur- face, evenly covered with adhesive (Fig. 10). This should be carefully checked, as any areas of the cavity that appear matt are an indication that insufficient adhesive was ap- plied to those sites. In the worst case, this could result in both re- duced bonding of the restoration in these areas and reduced dentine sealing, which may lead to post- operative sensitivity. If such areas are found in the visual inspection, additional bonding agent must again be selectively applied to them. In the next step, the cavity, meas- ured in advance with a periodontal probe (6 mm deep from the floor of the box to the occlusal marginal ridge),wasfilledwithAdmiraFusion x-tra in the area of the mesial box until a residual depth in the entire cavity of no more than 4 mm re- mained. At the same time, the mesialapproximalsurfacewasbuilt up completely to the level of the marginal ridge (Fig. 11). The restora- tive material was cured by a poly- merisation lamp (light intensity of > 800 mW/cm2 ) for 20 seconds (Fig. 12). The build-up of the mesial approximal surface converted the original Class II cavity into an ef- fective Class I cavity, and then the matrix system was removed, as it wasnolongerrequired(Fig.13).This facilitated access to the cavity with hand instruments for shaping the occlusal structures in the further course of the treatment and, owing to the improved visibility of the treatment area, allowed improved visual control of the material layers subsequently applied. The second increment of Admira Fusion x-tra filled the residual volume of the cavity completely (Fig.14). After the shaping (Fig. 15) of a functional, but uncomplicated, occlusal anatomy —which also helps to ensure rapid finishing and polishing—the re- storative material was cured again for 20 seconds (Fig.16). The vestibu- larcavitywasfilledinthenextstep. After removal of the rubber dam, the restoration was carefully fin- ished with rotary instruments and abrasive discs, and the static and dynamic occlusion adjusted. Dia- mond-impregnated silicone polish- ers(Dimanto,VOCO)werethenused togivethesurfaceoftherestoration a smooth and shiny finish. Figure 17 showsthefinisheddirectORMOCER restoration, which reproduced the originaltoothshapewithananatom- ically functional occlusal surface, physiologically shaped approximal contact and aesthetically acceptable appearance.Finally,afoampelletwas used to apply the fluoride varnish (Bifluorid12,VOCO)totheteeth. Final remarks Theimportanceofdirectcompos- ite-based restorative materials will continue to increase in the future. They produce scientifically verified, high-quality permanent restorations for the masticatory load-bearing posterior region, and the reliability ofthesehasbeendocumentedinthe literature.Theresultsofanextensive review have shown that the annual loss rate for composite restorations intheposteriorregion(2.2percent)is notstatisticallydifferentfromthatof amalgamrestorations(3.0percent).43 Theincreasingeconomicpressurein thehealthcaresectorhascreatedthe need for a simpler, faster and thus more cost-effective basic treatment alongsidethetime-consuminghigh- endrestorations.Forsometimenow, there have been composites with optimiseddepthsofcureonthemar- ketforthispurposethatcanbeusedto create clinically and aesthetically ac- ceptable posterior restorations using a procedure that is more cost-effec- tivecomparedwithtraditionalhybrid composites.44,45 Inadditiontothebulk- fill composites with classic metha- crylate chemistry, the range of prod- uctsonofferinthefieldofcomposite adhesivematerialswithalargedepth ofcurehasnowbeenexpandedwith anano-hybridORMOCERversion. Editorialnote:Alistofreferencesisavail- able from the publisher. Prof. Jürgen Manhart works in the Depart- ment of Resto- rative Dentistry and Periodon- tology at the University of Munich in Ger- many.He can be contacted at manhart@manhart.com. Fig. 15: Shaping of a functional, but uncomplicated, occlusal anatomy.—Fig. 16: Curing the restoration. The vestibular cavity was filled in the next step.—Fig. 17: Result: finished, highly polished restoration. The function and aesthetics of the tooth were successfully restored. Fig.12: Light curing of the restorative material for 20 seconds.—Fig.13: Situation after removal of the matrix.—Fig.14:The second increment of Admira Fusion x-tra filled the cavity completely. 12 13 14 15 16 17 DTNE0315_08-09_Manhart 02.11.15 11:03 Seite 2 121314 151617 DTNE0315_08-09_Manhart 02.11.1511:03 Seite 2