implants - international magazine of oral implantology

I case report _ prevention of implant resorption Fig. 1_Jose Conte (1997). Fig. 2_Jose Conte (2007). Fig. 3_ I.P.S.P.S. diagram for implants of 3.26, 3.76 and 4.10 mm in diameter. _Various surgical techniques for bone augmen- tation of the maxilla and mandible are mentioned in the literature. This article offers viable alternatives to maxillary and mandibular surgery, helping to prevent implant resorption in molar areas. _Back to the roots: “Implantology 2000” The implantology profession agrees that a greater number of implants to support the prosthesis is a de- termining factor of success. A greater number of im- plants decreases the number of pontics, improves the biomechanicsbyreducingstrainontheprosthesisand dissipatesstressesmoreeffectivelytothebonestruc- ture, especially at the crestal level. The maximum os- seous surface area and adequate bone density are re- quirements for long-term resistance to occlusal loads.7 Inaddition,thegreatestfunctionalsurfacearea is required in the crestal 5 mm of the implant body. Comparisons between natural tooth roots and implants show that increasing the surface area by increasing the number of implants is a prime require- ment for achieving long-term success of dental implants.10 In the past, the replacement of one molar with a single implant was widely accepted as the recom- mended standard practice.8 As an innovative and vi- able alternative to the current standard practice, re- placing mandibular molars with two implants and maxillary molars with three implants has been suc- cessfully applied since 1994, in other words one im- plantperrootlost.Thistechniqueofusingmultipleim- plants preserves the natural crown–root ratio of mo- lars. More importantly, multiple implants reduce and balance the occlusal forces. This reduction in occlusal forcesgreatlyreducesimplant–bonestressonthesur- face contact areas in the posterior regions of the mouthwherethemaximumstressisplacedonthemo- lars. Inthe1980s,forcereductionandsurfaceareawere difficult to balance in the posterior regions of the mouth.Studiesclearlydemonstratethattheforcesare often 300% greater in the posterior areas compared withtheanteriorregionsofthemouth.Bonedensities and strengths are 50 to 200% weaker in the posterior regionsofthemouth.Yet,implantswithagreatersur- facearea(accordingtolength)wereinsertedinthean- terior regions. Natural teeth do not have longer roots in the posterior regions of the mouth, where stresses aregreater.Instead,increasedsurfaceareaisachieved with a greater number of implants, placing two im- plantsineachlostmolar.Inavailableboneofadequate width, replacing the lost roots with the same number ofimplantsisrecommended,placedinthesameposi- tion and direction that nature created (within anatomic limitations),6 especially in cases in which only a few millimetres of bone remain between the cortical floor of the sinus and the crest of the ridge.10 This way, the distribution of the bite forces in key points proposed by Misch in his paper at the World Congress of Oral Implantology in Taipei in 2006 could be achieved using thin implants inserted in strategic positions,passingalongthesidesofthewallsofthesi- nus to create a tripod to support the maxillary molars andalongthesidesofthedentalnervetoformthebi- pod that mandibular molars need to support the oc- 44 Roots—44 Implants A case report Author_Drs Eduardo Topete A., Estela Topete Z., Eduardo Topete Z. & Alberto Topete Z., Mexico 06 I implants3_2011 Fig. 2 Fig. 3 Fig. 1