CAD/CAM international magazine of digital dentistry

I case report _ patient-specific abutments Fig. 11_Patient-specific abutment prior to insertion. Fig. 12_Complete individualised crown restoration on master cast. Fig. 13_Abutment insertion and mounting with a torque wrench at 25 Ncm. Fig. 14_Occlusal view of the inserted abutment. Fig. 15_Closing of the screw opening with Cavit (3M ESPE) prior to cementing the superstructure. It should be noted that, owing to the bevelled de- signoftheimplantsused,analmostseamlessinsertion into the natural osseous alveolar process is achieved, andthustheplasticcoverandtheprimarywoundclo- surearesimplifiedforthesurgeon.Thisisalsotheba- sisforaquickandsmoothhealingprocess. Three-dimensional bone structures can be pre- served using the above-mentioned OsseoSpeed TX Profile implant. Healthy bone is a prerequisite for op- timalprostheticrestorationwithregardtoaesthetics. The otherwise often necessary hard- and soft-tissue transplantscannowmostlybeavoided.5 Theextenttowhichatemporaryrestorationcanbe screwed together after prosthetic pretreatment and aftertheimplantregionhasbeenmoulded,orwhether a removable device can be used temporarily, depends significantly on the patient’s financial resources. In addition to the use of gingiva formers native to the system, temporary restorations aid the moulding, preparation and stabilisation of the peri-implant soft tissue during and after the healing phase. As the in- terim prosthesis guaranteed functionality and aes- thetics that satisfied the patient, additional moulding ofthesofttissuewasachievedthroughspecialgingiva formersorhealingabutments(Figs.4&5). Theresultsobtainedintermsofpreservationofthe marginal bone using the ASTRA TECH Implant System (DENTSPLY Implants) are documented in Palmer et al. (2000)andWennströmetal.(2005).9,10 Preservationof the marginal bone level and healthy soft tissue are indispensable for the long-term success of implant treatment both clinically and aesthetically. The bone provides the soft tissue with stability, while the soft tissueprotectsthebonefrommicro-organisms. A special feature of the implant system used is the patented Conical Seal Design, which prevents micro- movements and micro-gaps at the interface between theimplantandabutment,reliablyprotectingtheim- plant and bone from bacteria. The clinical relevance of the pump effect caused by micro-movement and possible crestal bone resorption were experimentally tested by Zipprich et al. (2007).11 Furthermore, arising stress is distributed farther into the bone and peak loads are simultaneously reduced.12, 13 In this regard, the preference for preserving the marginal bone level must be clarified as well. The implant–abutment con- nection is thus reliably sealed against bacteria and theboneistherebyprotectedfromexternalinfluences. Maintenanceofthesuperstructureisalsomadeeasier forthepatient. The integration of the abutment is simplified by the conical implant–abutment connection (Fig. 6). However, with regard to the bevelled OsseoSpeed TX Profileimplants,particularattentionmustbegivento the precise transfer of the clinical situation to the model being manufactured using moulding aids and transfer posts during precision moulding, which re- quiresspecificexperienceandagoodinstinct. TheindividualisedATLANTISabutmentsareagood solution for cemented crowns or bridges, as they guarantee optimal functionality, are the basis for sophisticatedprosthesesandareeasytouse. 24 I CAD/CAM 4_2012 Fig. 11 Fig. 12 Fig. 13 Fig. 15Fig. 14