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I research _ restoration Fig. 1_Load distribution during mas- tication shows marked increase in the molar and premolar area.23 Fig. 2_Occlusal view showing a missing first molar. The mesio-distal width is very wide and restoration couldn't compensate it leaving a space distally. Fig. 3_Proximal cantilever shown radiographic view of maxillary right first molar on standard Brå nemark implant with standard abutment (Nobel Biocare).1 _The single-tooth restoration has become one of the most widely used procedures in implant dentistry.1 In the posterior region of the oral cavity, bone volume anddensityareoftencompromised.Occlusalforcesare greater in this region and, with or without parafunc- tionalhabits,caneasilycompromisethestabilityofthe restorations(Fig.1).2,3 The single-molar implant-supported restoration has historically presented a challenge in terms of form andfunction.Themesiodistaldimensionsofamolarex- ceed that of most standard implants (3.75 to 4.0 mm), creatingthepossibilityoffunctionaloverloadresulting inthefailureoftheretainingcomponentsorthefailure of the implant (Figs. 2 & 3).4 Wider-diameter implants have a genuine use in smaller molar spaces (8.0 to 11.0 mm) with a crestal width greater than or equal to 8mm(Fig.4a).5 Clinicalparametersgoverningthepro- posed restoration should be carefully assessed in light oftheavailabilityofimplantsandcomponentsthatpro- videamyriadofoptionsindiameter,platformconfigu- rationsandprostheticconnections.Manyofthenewer systems for these restorations are showing promising resultsinrecentclinicaltrials.6-8 Ithasfurtherbeensug- gested by Davarpanah and others,9 Balshi and others,2 Englishandothers10 andBahatandHandelsman11 that the use of multiple implants may be the ideal solution for single-molar implant restorations (Figs. 4 b & c). Moststandardimplantsandtheirassociatedprosthetic components, when used to support a double implant molarrestoration,willnotfitinthespaceoccupiedbya molar unless the space has been enlarged (12 mm or larger).4 Moscovitchsuggeststhattheconceptofusing 2implantsrequirestheavailabilityofastrongandsta- ble implant having a minimum diameter of 3.5 mm. Additionally, the associated prosthetic components shouldideallynotexceedthisdimension.2 Finite element analysis (FEA) is an engineering methodthatallowsinvestigatorstoassessstressesand strainswithinasolidbody.10-13 FEAprovidescalculation ofstressesanddeformationsofeachelementaloneand the net of all elements. A finite element model is con- structedbybreakingasolidobjectintoanumberofdis- crete elements that are connected at common nodal points. Each element is assigned appropriate material properties that correspond to the properties of the structure to be modeled. Boundary conditions are ap- pliedtothemodeltostimulateinteractionswiththeen- vironment.14 Thismodelallowssimulatedforceapplica- tiontospecificpointsinthesystem,anditprovidesthe resultant forces in the surrounding structures. FEA is Single molar restoration Wide implant versus two conventional Authors_Prof Dr Amr Abdel Azim, Dr Amani Zaki, Dr Mohamed el Anwar, Egypt 06 I implants4_2010 Fig. 2 Fig. 3Fig. 1