Implants

26 I I research_ Single molar restoration implants1_2013 _The single-tooth restoration has be- comeoneofthemostwidelyusedprocedures in implant dentistry.1 In the posterior region of the oral cavity, bone volume and density are often compromised. Occlusal forces are greater in this region and, with or without parafunctional habits, can easily compromise the stability of the restorations (Fig 1). 2, 3 The single-molar implant-supported res- toration has historically presented a chal- lenge in terms of form and function. The me- siodistal dimensions of a molar exceed that of most standard implants (3.75 to 4.0 mm), creating the possibility of functional overload resulting in the failure of the retaining com- ponentsorthefailureoftheimplant(Figs2& 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 4 a).5 Clinical parameters gov- erning the proposed restoration should be carefully assessed in light of the availability of implants and components that provide a myriad of options in diameter, platform con- figurationsandprostheticconnections.Many of the newer systems for these restorations are showing promising results in recent clini- cal trials.6-8 It has further been suggested by Davarpanah and others,9 Balshi and others,2 English and others10 and Bahat and Handels- man11 that the use of multiple implants may be the ideal solution for single-molar implant restorations (Figs 4 b & c). Most standard implants and their associ- ated prosthetic components, when used to support a double implant molar restoration, will not fit in the space occupied by a molar unless the space has been enlarged (12 mm orlarger).4 Moscovitchsuggeststhatthecon- cept of using two implants requires the avail- ability of a strong and stable implant having a minimum diameter of 3.5 mm. Additionally, theassociatedprostheticcomponentsshould ideally not exceed this dimension.2 Finite element analysis (FEA) is an engi- Singlemolarrestoration- Wideimplantversustwo conventional Author_Amr Abdel Azim, Dr Amani M. Zaki & Dr Mohamed I. El-Anwar, Egypt Fig. 1 Fig. 2 Fig. 3 Fig. 1_Load distribution during mastication shows marked increase in the molar and premolar area23 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 Brånemark implant with standard abutment (Nobel Biocare)1