DTUK13

17Implant TribuneMay 17-23, 2010United Kingdom Edition For more information please contact your dental retailer www.septodont.co.uk Septodont Ltd, Units R & S Orchard Business Centre, St Barnabas Close, Allington, Maidstone, Kent ME16 0JZ - Tel: +44 (0)1622 695520 Anaesthetics • Endodontics • Restorative Dentistry • Dental Surgery • Prosthetic Dentistry • Disinfection & Hygiene The UK’s leading supplier of dental anaesthetic, Septodont, already bring you the high quality Septoject and Septoject XL needles and would now like to introduce a new development to Ultra Safety Plus. Ultra Safety Plus syringe is a sterile, disposable and self aspirating syringe system with a pre-mounted needle. Its use means needle stick injuries can be virtually eliminated. With the option of a NEW single use handle (non sterile), Ultra Safety Plus is now 100% disposable. implant crown when a vertical force was applied.’ Researching the literature, only one paper by Schwedhelm et al. (2003) has been identi- fied addressing the cementation problem in implant-supported crowns. He suggested a lateral crown venting to allow elimina- tion of cement excess and reduce deflection/deformation of the prosthetic part as well nocive forces to the implant. A clinical case study Missing tooth 46 was replaced by an implant: Internal Implant RBT, Laser-Lok 4.0 x 12mm, 4.5 Platform (Biohorizons UK, 17 Wellington Business Park, Dukes Ride, Crowthorne, Berk- shire RG45 6LS). After adequate osseointegration time (three months after insertion), the second-stage surgery has been performed and the gum sculpted with a provisional. A correctly seated implant allows the use of the primary attached titanium abutment for the impression as well as to be used as definitive abutment. The preparation of the abutment is performed by the technician. It is important to make sure that a nice prep margin is defined. This will ease the removal of the ce- ment at the crown margins. The author prefers a tech- nique of cementation with coro- nal venting. The presented crown design addresses the following technology shortcomings: • Cementation will easier par- don framework discrepancies. • Coronal access will facilitate and allow screw retightening at any needed time. • Coronal access will facilitate excess cement evacuation and clearly facilitate a better fitting. The laboratory delivered the prepped abutment mounted into the transfer key. The PFM crown (high precious metal) guarantees a coronal access to the screw. The abutment will be tight- ened according to the indica- tions of the manufacturer us- ing a torque control device. The abutment access is closed using polytetrafluoroethylene (PTFE) tape (plumber tape) to seal the screw access channel to protect the screw head of the abutment as described by Moráguez et al. (2010). The tape will easily fa- cilitate future screw access and findings proved a less bacterial contamination manifested by bad smell. The crown will be seated using a luting cement, produc- ing a very thin cement film. I favour active cemenatation us- ing vibrating approach to ease excess cement evacuation and avoid misfit and/or defelection or restoration. Conclusion Adequate fit of the prosthetic restoration can be guaranteed only by understanding prosthet- ic biomechanic shortcomings. Researching the literature helps finding solutions. I successfully managed to elaborate and dem- onstrate a simple solution for a difficult, mostly ignored prob- lem: perfect marginal fit and re- trievability of implant retained fixed prosthetics. DT References 1. Goodacre CJ, Kan JY, Rungcharassaeng K. Clinical complications of osseointegrated implants. J Prosthet Dent 1999;81:537-52. 2. Chee W, Felton DA, Johnson PF, Sullivan DY. Cemented versus screw retained implant prostheses: which is better? Int J Oral Maxillofac Implants 1999;14:137-41. 3. Hebel KS, Gajjar RC. Cement-retained versus screw-retained implant restorations: achieving optimal occlusion and esthetics in implant dentistry. J Prosthet Dent 1997;77:28-35. 4. Michalakis KX, Hirayama H, Garefis PD. Cement-retained versus screwretained implant restorations: a critical review. Int J Oral Maxillofac Implants 2003;18:719-28. 5. Breeding LC, Dixon DL, Bogacki MT, Tietge JD. Use of luting agents with an implant system: part I. J Prosthet Dent 1992;68:737-41. 6. Rodriguez AM, Orenstein IH, Morris HF, Ochi S. Survival of various implant-supported prosthesis designs following 36 months of clini- cal function. Ann Periodontol 2000;5:101-8. 7. Cavazos E, Bell FA. Preventing loosening of implant abutment screws. J Prosthet Dent 1996;75:566-9. 8. Doerr J. Simplified technique for retrieving cemented implant restorations. J Prosthet Dent 2002;88:352-3. 9. Okamoto M, Minagi S. Technique for removing a cemented superstructure from an implant abutment. J Prosthet Dent 2002;87:241-2. 10. Chee WW, Torbati A, Albouy JP. Retrievable cemented implant restorations. J Prosthodont 1998;7:120-5. 11. Clausen GF. The lingual locking screw for implant-retained restorations – aesthetics and irretrievability. Aust Prosthodont J 1995;9:17-20. 12. Valbao FP Jr, Perez EG, Breda M. Alternative method for retention and removal of cement-retained implant prosthesis. J Prosthet Dent 2001;86: 181-3. 13. Pow EH, Wat PY, Chow TW. Retrievable cement-retained implant-toothsupported prosthesis: a new technique. Implant Dent 2000;9:346-50. Intraoral picture illustrating the estab- lished gum architecture. The prepped abutment mounted into the transfer key. The abutment seated in vivo using the transfer key. The postoperative x-ray demonstrates the perfect fit of the abutment – restoration margin. Clinical picture demonstrating a good emergence profile, nice and healthy gum coloration (as no nocive forces applied), and an excellent esthetic integration in the remaining tooth arcade. The occlusal access was closed using composite resins. The PFM crown with coronal access to the abutment screw. About the author Dr Liviu Steier (PhD) is Spezialist fuer Prothe- tik (www.dgzmk.de) and specialist in Eendodon- tics (GDC-UK). He is an honorary clinical associ- ate professor at Warwick Medical School and course director of the MSc in Endodontics (www.war- wick.ac.uk/go/dentistry). He is a mem- ber of the Scientific Advisory Board for the Journal of Endodontics (AAE) and maintains a private referral practice for endodontics, implantology, etc at 20 Wimpole Street, W1G 8GF London (www.msdentistry.co.uk).