1 / 15

Complete Guide to Dental Impression Materials and Procedures

Learn about impression materials, trays, mixing ratios, setting times, lab procedures, and more for accurate dental impressions.

clintoni
Download Presentation

Complete Guide to Dental Impression Materials and Procedures

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapters • 46 Impression Materials • 47 Lab Materials and Procedures

  2. Alginate Impressions • Preliminary Impressions • Show teeth and surroundings tissue • Used for diagnostic aids • Should fluff canister before using, (material settles and packs down) • Negative reproduction of the teeth and surrounding tissues

  3. Rubber Base • Final Impressions • Most Accurate impressions • Measure equal amounts of catalyst and base material • Homogeneous mix • Catalyst incorporated into base when mixing • Elastomeric impression material

  4. Types of Trays • Full • Quadrant and triple trays • Section (anterior) • Plastic/metal • Perforated/solid • Stock • Custom • Vacuum formed

  5. Ratio for mixing Alginate • Maxillary—3 scoops of powder to 3 measures of water • Mandibular—2 scoops of powder to 2 measures of water • Too much water makes a thin mix and takes a long time to set • Too little water makes a stiff mix and set to quickly • Plaster (gypsum product)

  6. Loading Alginate Trays • Mandibular trays—two increments (one on each side of tray) • Maxillary trays—one increment from the posterior

  7. Removing Trays • Mandibular trays—firm lifting motion • Maxillary trays—release posterior and then anterior

  8. Seating Trays • Press posterior down first • Always explain to patient what you are doing • Take mandibular impression first (patient will have better understanding of what is taking place) • Patient should be seated in the most upright position.

  9. Seating Cont. • Ask patient to swallow before seating tray, (this removes excess saliva and possible air bubbles) • Ask patient to lean forward when tray is placed. • Ask patient to breath through their nose • Have patient lift feet off of chair, if they gag

  10. After removing trays • Rinse patients mouth out • Rinse with water and shake off excess • Spray impression with disinfectant • Wrap in wet paper towel, if you can not pour immediately • Place patient’s name with impressions

  11. Pour Methods for Plaster • Inverted pour – one large mix in single step • Box pour – surrounded with box of wax • Double pour – (fab mold)– anatomic first and art portion second

  12. Setting Time • Things that can affect setting time of alginate • Water temp—(warmer the water, the faster the set time) • Water to powder ratio (the more powder the faster the set) • Normal set or fast set alginate

  13. Dental Labs • Most labs are in a separate area of the office, usually the back of office or the basement. • Well ventilated • Items might include: • Model trimmers • Vaccum formers • Lab burs and handpiece

  14. Models • Two portions of the cast • Anatomic portion is created from the alginate impression, shows teeth and tissues • Art portion forms the base of the cast • Trimmed models • Maxillary model will be pointed at the anterior portion • Mandibular model will be rounded at the anterior portion • Positive reproduction of teeth and surrounding tissues

  15. Bite Registrations • Reproduction of the occlusal relationship of the maxillary and mandibular teeth, (when mouth is occluded) • Can be preformed or made in lab office

More Related