Gary Smith 2.0

-Notches on upper wax rims should not be parallel. This is so that the bite record can't slide left or right
-Wax is a better bite recorder than PVS as you can control it easier and you can't see anything with PVS bite reg.
-In the tooth try in stage for a remount or in a processed denture for a lab reline Dr. Smith applies wax to the upper plate. He softens a sheet of wax ~ 1.5x the AP length of the denture and places it in line with the posterior part of the denture. He then folds the wax over at the front and adapts the wax to the palate. A heated wax knife is used against the teeth to remove the labial wax at the buccal cusp tips and incisal edges. a flame is used to soften the wax over the occlusal surfaces and is placed in the patient's mouth to bite onto.
-Wax rims should be adjusted to meet when the patient bites together. If there is contact prematurely then it is preferred to have this at the front. The small gap at the posterior will then be closed with wax in the bite. Contact at the front ensures that the OVD is correct. If the gap is wider on one side then a folded wax sheet slightly wider than the rim (For the bite reg) is cut and placed on the mandibular rim at that side. Once melted, it is shaped to fit the rim which increases its height
-A tip i really liked was that he used a watercolour purple (Stays on better) to draw on the impressions/rims. Dipped in a bowl of water first, this draws like a paint brush on surfaces.
-Greenstick isn't heated till it sags. he heats the outside by rotating first. Then he heats only one side and uses a patting motion onto the tray. Don't worry about the roughness or streaks at the moment. The recently applied greenstick is heated with a flame till shiny but not flowy. It is dipped in the water only once just before it is placed in the patient's mouth. After taking it out of the patient's mouth, always dry it with a tissue as it is easier to tell if the greenstick is matte. Matte means the greenstick has been shaped by the tissues, shiny or streaky is a common mistake by inexperienced operators and means that the greenstick was either set or underextended by the time it went in. You don't need a lot of greenstick provided your tray is properly extended. dry greenstick also helps the next lot of greenstick to stick to the tray. Greenstick won't stick to wet surfaces. You can wet your finger if you need to pat down the greenstick
-If the anatomy isn't right, make it right. Preprosthetic surgery is necessary for unfavourable undercuts and frenal attachments.
-In his secondary impression stage for full dentures he does a 2 stage impression. After greenstick, he places a zoe mix around the periphery. This is a "Periphery check impression" and is used by Dr. Smith to check for proper extensions. Greenstick showthrough is trimmed with a bur. ZOE is then applied to the palate and ridge areas for a 2nd impression.
-The post dam peaks should be at the depression of the greater palatine nerve. It should be symmetrical. Draw it on the rim with a pencil and use a wax knife to add wax onto the post dam area. A heated wax knife is pressed onto a stack of wax to pick some up onto the upper surface. this is reheated and slid along the intaglio surface with the tip of the knife at the purple line. Reheat with a flame to smoothen and soften. This is pressed back into the patient's mouth and trimmed. It is better to apply it onto the rim (as opposed to scoring the cast in the lab) and retried in as you can tell if it isn't retentive. If not retentive then it must be redone.
-With reline impressions, the bite almost always changes (As the tissue surface of the denture has changed and the denture is raised off the tissues.) Therefore a bite must be taken (with an impression of the opposing arch (If not a double reline). Ask the lab to mouth, reline and fix the occlusion after.
- It isn't ideal to send for processing when the occlusion isn't perfect. Adjusting at the insertion stage means that the patient is getting a "second hand denture" straight up.
-Apply soft relines/impression material with a thin spatula
-Hold the lip out of the way (Forwards) with impressions/soft relines for at least 1 minute otherwise the labial soft tissues will press but labial surface of the labial flange in and will cause a sharp flange to develop.
-Today I saw a F/- with a molar opposing a mesially tipped lower molar with a mesial edentulous space. The opposing denture tooth was placed more posteriorly leaving an "edentulous space. It was set up to occlude with the distal marginal ridge of the tipped lower molar. If it was set up normal with the upper tooth occludin with the whole of the denture tooth, when the patient protrudes, all the force would be concentrated on the upper molar as the angle of the lowar molar would rise faster than the disocclusion of the molars.
-Zinc oxide paste can only be applied to dry mucosa. Use gauze to dry mucosa carefully (as the place is often sore)
-Black felt marker can be used over showthrough areas on fitchecker as the fitchecker is often displaced by the bur.
-Apply the liquid portion of the soft reline with the tip of your glove to the tissue surface of the denture before you apply the mix. This helps with adhesion.
-Mistakes made with almost all dentures:
=Overextended: People use the primary model to choose the extension of the denture. You have to check in the patient's mouth to see the extension of the muscle attachments. This should then be drawn onto the 2nd impression.
=Overbite too large: If it is greater than 1mm overbite then on protrusion or incising (Which is the first natural movement of mastication) the denture will tip anteriorly and pressure will be applied to the anterior ridge resulting in resorption. Ideally there will be incomplete overbite of less than 1mm so that there is no anterior contact in MIP. sliding forward will be only posterior contact till anterior teeth are contacted. at this point, posterior teeth should still be touching. Overjet is less important but OJ over 5mm will mean that anterior teeth won't occlude and patients shouldn't incise their food but should cut up their food. anterior bite planes can be used for anterior occlusion. A patient today had only mini anterior bite planes over the canines to provide more anterior stability.