Fitting the Bridge
If you have used the stone model for initial assembly of the beam and clip, you should be ready to cement the assembled single unit into the teeth. Prior to cementation, go to your kit and select either the red of the brown dead soft covered wire that you will use to loop each tooth and then secure by tying the 2 ends with a hemostat and twisting until the twisted section is snugged against the tooth facing the midpoint on the buccal. This simultaneously prevents resin cement from flowing into the gingival space and also creates a future embrasure opening(for flossing and interdental cleansing) when the wire is removed. This wire is twisted tight with a hemostat before cementation, and then withdrawn after cementation, leaving a perfect embrasure space for flossing. You are now ready to isolate the teeth from saliva using a correct cotton roll technique or a device such as Isolite that will be described in the cementation step.
Teeth Preparation
At the placement visit(same as consult visit or the following visit), the dentist anesthetizes the abutment teeth. Now prepare the proximal surfaces of the tooth posterior to the gap and anterior to the gap in the same way that you prepared the stone model. Again you are going to be drilling a box prep 4mm vertically deep, 3mm wide and 2mm axially. Use the special periodontal probe with the rectangular box shape as your guide to see if you have drilled enough. If the rectangular end fits completely into your tooth preparation then your drilling is correct.
Occlusal Adjustment
Ideally, we would like to have a patient identical in their centric occlusion (CO) and their centric relation (CR). However, most patients , because they are missing one or more teeth will have an altered plane of occlusion. Because of the need for a stable bite in both centric closure and excursive movements, it is important to adjust the bite prior to inserting the bridge. The best way to do this is to place horse shoe red /blue articulating paper (made by SVEDIA) on the lower arch WITH THE BLUE SIDE DOWN and then have your patient bite edge to edge anteriorly, and then slide back with the lower jaw into a full closure position. You should only see markings on the lower buccal cusp tips, and slightly on to the buccal cusp curvature. You should also see markings on the lingual slopes of the upper buccal cusps. You should not see any markings on the inner surface of the lower buccal cusps and if you do they are to be removed with a small football-shaped diamond bur WITHOUT TOUCHING THE BUCCAL CUSP TIPS. You should also not see any markings on the buccal slopes of the upper lingual cusps. If you do, those markings are to be removed with the diamond bur WITHOUT TOUCHING THE LINGUAL CUSP TIPS.
When these marking on the incorrect slopes have been removed, wipe off all markings with 2” x 2” gauze, replace the red/ blue horse shoe paper, have the patient close on their back teeth, and from that position have them slide to the right side until they are edge to edge on the upper and lower right cuspids. Now have them close back to the original full closure position by sliding on their teeth in a power stroke. Have them open, and check the contralateral side. On the molar teeth make sure that there are no marking on the buccal slopes of the upper lingual cusps and no marking on the lingual slopes of the lower buccal slopes. These will be balancing interferences that must be removed. Next, have them repeat this excursive slide on the left side and check for balancing interferences on the right side. Again remove any interferences on the molar teeth on the buccal slopes of the upper lingual cusps, and the lingual slopes of the lower buccal cusps.
Next, check the buccal slope markings on the molar and bicuspid teeth of the lower arch and make sure all markings are even on the buccal slopes and the buccal cusp tips. Now check the lingual slopes of the upper buccal cusps and make sure those markings are all equal. At this point you should have eliminated most interferences on the pathway back to centric relation.
Next remove all markings from all cusps and slopes with gauze, replace the red blue horse shoe paper, and have the patient close on their back teeth, and have them tap 2 or 3 times in that position and ask them to open. Now check to see if all lower buccal cusp tips on molars and bicuspids have little blue dots on them. Check to see that the upper lingual cusp tips have little red dots on them. If so, then the patient should have a good centric occlusion within a good centric relation. If you ask them to tap their teeth on the back teeth, you should hear a very hard clear staccato sound rather than a lower more muffled sound. When the patient slides their teeth around, they should also observe to you that they can also glide easily in any direction.
Lastly, place thin cellophane paper on the lower front teeth and ask the patient to close on their back teeth. Try to pull the cellophane paper through on their front teeth towards yourself, and, if the paper grabs, you will need to adjust the centric bite of the lower incisal teeth against the lingual surfaces of the upper incisal teeth. Use the thinnest articulating paper that you have, placing it on the lower front teeth, have the patient bite on the lower teeth in CR, and tap tap tap. Check upper lingual markings and remove any heavy markings with a small pear shaped diamond bur. Your objective is to eliminate lingual markings and retest until the markings have just barely been removed. Retest with the cellophane paper and continue the process until the cellophane paper no longer grabs on the incisal teeth when the patient is biting in CR. At this point you are finished with your occlusal adjustment and you are ready to place Bond-A-Bridge™..