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Dental Tribune Middle East & Africa Edition | 3/2017 RESTORATIVE 37 ◊Page 36 to be cut back accurately between 1.5 and 2.0mm for the placement of pink porcelain and the forming of the 12 individual tooth preparations for the acceptance of crowns at a later stage (Figures 9 to 11). The pink porcelain framework was tried in the mouth on top of the precious metal copings and abut- ments (Figure 12). A passive fi t was confi rmed and jaw registration proceeded to confi rm the original centric relation position on the semi- adjustable articulator. Verifi cation at this stage is an important safeguard. When cementing the copings to the framework any discrepancies in fi t will be highlighted and the frame- work may not seat onto the original model. In these instances an acrylic and stone model is cast and re- mounting in the articulator is neces- sary. As described previously, the passive fi t of the large framework on abut- ments also leads to uneven thick- ness of cement lutes, which, if the cement is of a temporary nature, will wash out leading to the poten- tial for overstressing of certain im- plants (Parel, 2000). Intentionally this technique is to use a composite luting cement in order to pick the copings up from the abutments into the framework and have the com- posite as the major cement lute, so avoiding cement washout often seen when using the softer cements. This was done intraorally using ‘Panavia’ cement (Mortia) after the techni- cian has sandblasted the internal aspects of the porcelain framework and copings for greater retention (Jorgennsen, 1955) (Figures 13 & 14). The end result of this would then be that a perfectly passive framework would be achieved whereby the fi - nal cementation process could be achieved with a soft cement, with the ideal cement thickness to pre- vent washout. Individual Crowns Individual porcelain-fused-to-metal crowns were then fabricated accord- ing to the ‘Golden Proportion’ as de- scribed by Leving (1981). These were tried in place on the framework to fi nally determine aesthetics and oc- clusion prior to the crown being ad- hesively cemented to the previously silicoated metal fi tting surface of the crown and metal tooth preparation by the dental technician (Figures 15 to 17). This technique allows for bet- ter aesthetic reproduction of detail in that each crown can be built up over a period of time to create the illusion of a natural tooth (Goldstein, 1977). The patient can, if they so require, also fl oss between the crowns to give a psychological improvement in that their teeth feel more natural. Maintenance Maintenance also means that should a piece of porcelain on one crown fracture, the crown itself can be cut off, impressions taken and a new crown fabricated by the techni- cian and fi tted at any stage. Thus the maintenance is now similar to that of a full mouth reconstruction on individual teeth. The custom made abutments were tightened to 32Ncm using anti-rotation jigs and the bridge cemented passively in the mouth with Temp-Bond (Kerrs) (Fig- ures 18 to 20). Case Study Two This gentleman was referred from his practitioner in Bolton with failing restorative and implant work (Figure 21). The same procedures as in Case Study 1 were performed, this time in the maxilla (Figures 22 to 27). The variable here was that two remaining teeth were also used as abutments and screw block joined the tooth- supported framework on one side to the implant-supported frame- work on the other side. The guiding principles were the same however, that a purely passive fi tting full arch restoration was achieved with maxi- mum aesthetics and potential for long term maintenance. The same technique can be used with acrylic / metal bridges when wishing purely to improve the fi t of large acrylic metal castings (Figures 28 & 29) Conclusions The fi nal end results in all cases show aesthetic form and function with a truly passive fi t and a long term maintenance potential unlike any other form of full arch restoration, and is the treatment of choice for full arch restorations on implants. Acknowledgements I would like to thank Bradley Moore and John Wibberley, dental techni- cians, for their help in this case, and Dr Peter Wohrle for his excellent teaching methods. Editorial note: References available on request from the publisher. Professor Paul Tipton BDS, MSc, DGDP RCS (UK) DENTAL SURGEON Visiting Professor of Restorative and Cosmetic Dentistry, City of London Dental School | www.colds.co.uk SPECIALIST IN PROSTHODONTICS | www.drpaultipton.co.uk T Clinic @ Manchester , London | www.tclinic.co.uk TIPTON TRAINING Ltd | www.tiptontraining.co.uk www.bard.uk.com President of the British Academy of Restorative Dentistry (BARD) Monolithic restoration: inside and out Composite materials have undergone signifi cant improvements to allow enhanced esthetic results in recent years. The advent of bulk-fi ll materials and universal adhesives has resulted in a streamlined application procedure By Dr Eduardo Mahn, Chile Restoring teeth after endodontic root canal therapy has always presented a challenge. The wide range of mate- rials available for post-endodontic treatment is paralleled by an equally large range of selection criteria. Glass ionomer cements and composite resin materials are generally the ma- terial of choice for clinical situations that require no endodontic posts. Sometimes amalgam is also em- ployed because of legacy use. When endodontic posts are required, more treatment options are available as the pulp chamber is fi lled with an ad- ditional material after placement of the endodontic post. Prior to the advent of adhesive den- tistry, cast metal posts presented the preferred treatment option. In such cases, a customized cast metal post and core build-up were placed in the root canal and pulp chamber and cemented using a zinc phosphate cement. Due to the rising demand for glass fi bre endodontic posts, composite cements are now being increasingly utilized. This has led to the rise of two different clinical ap- proaches: 1. The fi rst approach is to create a monoblock, consisting of the core build-up material and the endodon- tic post. For this purpose, the core build-up material is required to fea- ture a fl owable consistency that is suitable for cementing the endodon- tic post. At the same time, the mate- rial should offer a suffi ciently high level of strength and stability to be used as a core build-up. 2. The second approach is to fi ll the tooth with a universal composite us- ing a rather time-consuming layer- ing technique either in conjunction with an endodontic post or without. tion can often not be achieved in these teeth. The need for a post is often diminished in posteriors with two or more remaining walls in particular. Most users prefer the fi rst option be- cause this approach affords a more effi cient method than the second. It should be noted that the use of an endodontic post is in many cases of- ten not necessary. The indication for insertion of a root canal post is based on the extension of the contact sur- face. This is often the case in molars be- cause of their large pulp chambers. Without a post, appropriate reten- Bulk-fi ll composites What are known as bulk- fi ll composites were introduced a few years ago. Given the increased translucency of these materials, cli- nicians were for the fi rst time able to place single increments in a thick- ness of up to 4mm. This means that most pulp chambers can be fi lled using one or at maximum two steps. Fig. 1: Preoperative situation: tooth in need of treatment due to deep caries reaching into the pulp chamber The material is 100 % compatible with the composite cement used for cementing the glass fi bre post in the root canal. ÿPage 38 Join Hands-On Training 01 - 08 May 2017 www.cappmea.com/cadcam DUBAI Hands-On Training in Dubai Digital Smile Design Part 1 & 2 Tutor: Dr. Eduardo Mahn, Chile Date: 01 & 02 May 2017 | 09:00 - 18:00 Accreditation: 14 CE Credits | HAAD 14 CME Closing Diastemas and Correction of Peg Laterals Tutor: Dr. Eduardo Mahn, Chile Date: 03 May 2017 | 09:00 - 18:00 Accreditation: 7 CE Credits | HAAD 7 CME Inlays, Onlays and Oclusal Veneers (Preparation and Cementation) Tutor: Dr. Eduardo Mahn, Chile Date: 04 May 2017 | 09:00 - 18:00 Accreditation: 7 CE Credits | HAAD 7 CME Post-endodontic-treatment: Should we place posts, do crowns or just composites and onlays? Tutor: Dr. Eduardo Mahn, Chile Date: 05 May 2017 | 09:00 - 18:00 Accreditation: 14 CE Credits | HAAD 14 CME Non-Prep-Veneers and Modifi ed Non-Prep-Veneers Tutor: Dr. Eduardo Mahn, Chile Date: 06 May 2017 | 09:00 - 18:00 Accreditation: 7 CE Credits | HAAD 7 CME Direct Veneers: How to Create the Right Shape... Tutor: Dr. Eduardo Mahn, Chile Date: 08 May 2017 | 09:00 - 18:00 Accreditation: 7 CE Credits | HAAD 7.25 CME