StomatologyEduJournal1-2015 | Page 35

BASICS OF FUNCTIONAL CLINICAL AND INSTRUMENTAL DIAGNOSTICS AND PRETREATMENT BEFORE FINAL ORAL REHABILITATION Figure 13. Carefully-made alginate impression with dammed and stopped Rim-Lock trays are essential for creating flawless working casts Figure 14. After pouring with dental stone, the models should be kept in a hygrophoree (air-tight plastic container) to harden Figure 15. The completed casts of this patient fit tightly with no play in habitual position. Figure 16. To prepare a centric relation record, the top side of a mounting tin foil plate is thinly coated with TempBond to take cusp impressions of the maxilla in a hygrophore (e.g., air-tight plastic container with a damp sponge); it is never appropriate to wrap the alginate impression in wet paper towels or napkins, even for short-term storage. After pouring the impressions with dental stone, they should be stored in the hygrophore until the stone has hardened (Fig. 14), since this greatly improves the quality of the casts.5 In the habitual relation, this patient’s finished casts fit tightly with no play, so that occlusal interferences were not discernable in this phase (Fig. 15). The casts are then mounted in the articulator and adjusted to the TMJ, as follows. down with moderate force, creating a minimal opening of the bite. Next, the top and bottom surfaces of the mounting plate are coated with an adhesive polish. The top surface is then thinly coated with a eugenol liner (Temp Bond). Without using pressure, the plate is adapted to the maxilla, and held by two fingers in the area of the rows of teeth until hardening and removal (Fig. 16). In preparation for taking the actual registration, the patient should sit upright and relaxed in the chair; the head should never be turned or stretched in any direction20 To decouple occlusion and relax the muscles, slightly moistened cotton rolls are placed in the premolar region (Fig. 17) In this case, a protrusion record for individually adjusting the horizontal condylar path inclination was not necessary, since the values for these angles (SKN) and the mediotrusion paths (TKN) were already available from the electronic registration (see Fig. 12). Centric relation record Preparations are made for taking the centric relation record (synonym: bite registration). A mounting tin foil plate (or “Beauty Pink” wax) is cut to maxillary size, placed between the patient’s teeth, and individually pre-formed through biting 125