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CDE0211

08 I I MICD _ occlusal force management cosmeticdentistry 2_2011 _patient discomfort owing to difficult occlusion initially post-insertion; _potentially shortened restoration lifespan. These sequelae result from the lack of repeated inter-occlusal remounts, which conventional prosthodontic cases commonly undergo. Re- mounting at metal try-in, porcelain bisque try-in and possibly once more prior to prosthesis instal- lation greatly improves the accuracy of the true maxillo-mandibular, inter-arch spatial relation- ships (Fig. 4). This reduces the number of occlusal adjustments required at insertion, thereby pre- servingrestorativematerialthicknessandrestora- tion strength. Adhesive restorations are almost incapable of being reliably remounted. Because of the minimal preparation configuration of partial coverage, non-bonded, all-ceramic restorations, they are unstable on their supporting teeth. Mousses, waxes, silicone putty, injected impression materi- als and impression tray seating can all easily dis- lodgethenon-bondedrestorationsfromtheirsup- porting teeth when taking inter-occlusal records. The movement of non-bonded restorations can also occur during a “pick-up” or transfer impres- sion. The instability of non-bonded restorations complicates all aspects of any remounting pro- cedure greatly. Without the series of laboratory remounts that a cemented prosthesis often undergoes, the all-ceramic restoration is susceptible to signifi- cant spatial misalignment and excessive occlu- sal force that can go undetected clinically until after the insertion has been started. This lack of proper detection of the location of problematic force is worsened by the fact that articulating paper markings do not measure the occlusal forces or the occlusal contact timing sequence in any quantifiable way, regardless of the false and often-advocated paper marking beliefs (Fig. 5).7–16 Poor maxillo-mandibular spatial relationships and occlusal force detection can be reliably over- come when an MI clinician employs computer- guided occlusal analysis technology at restoration insertion (T-Scan III, Tekscan; Figs. 6a & b). When properly used after the completion of bonding procedures, this digital occlusal technology helps to locate regions of excessive occlusal force accurately within the occlusal surfaces and in- cisal edges of the newly placed restorations. The clinical reduction of these excessive forces leads to easier post-insertion acceptance of the new occlusion and increases the restoration’s life- span. _Computer-guided occlusal analysis system The T-Scan III Computerized Occlusal Analysis System offers precision technology that analyses occlusal contact force and time sequences in 0.003-second increments and graphically displays them in movie form.17,18 The system simplifies occlusal adjustments at aesthetic prosthesis in- sertion, as it quickly isolates excessive force con- centrations and time-premature contacts, so their eradication is predictable and effective (Fig. 7). The preservationandlongevityofceramicrestorations are enhanced, as any potentially destructive oc- clusal forces are isolated at delivery, and then removedpriortothepatient’slong-termuseofthe new smile design prosthesis. Fig. 7_T-Scan III graphical display illustrates excessive occlusal force in colour for simplified analyses by the clinician. Fig. 8a_T-Scan III sensor schematic. Fig. 8b_T-Scan III high definition recording sensor. Fig. 9_Legend of colour-coded occlusal force data. Fig. 10_Doughnut-shaped paper mark supposedly indicates high force. Fig. 8a Fig. 8bFig. 7 Fig. 10Fig. 9