tips and tricks

Today I missed an ulcer on the patient's lower lip, on further investigation it turns out the patient has had that same ulcer for a number of years and a previous clinician had recommended a biopsy which she didn't return for. Missing this was a mistake and I need to try harder to check the soft tissues and pay attention to detail. To describe lesions use: 1. Site a. anatomic location (e.g tongue, floor of mouth, palate) b. Adjacent features (E.g adjacent to 34 tooth) c. Unilateral/bilateral d. Localised/Generalised 2. Colour 3. Morphology a. Diameter (mm) b. Single/multiple c. Separate/Coalescing d. Raised/flat/depressed e. Fluid filled/tissue filled/texture f. Margins (Regular/irregular, Raised/smooth, Colour)

Alginate can deteriorate in its powder form within 3 days of opening the container. Exposure to humidity or heat causes thin mixes, altered setting times, reduced strength, high deformation. Contamination with gypsum products in the bowl should be avoided as it can accelerate its set. Don't mix stone and alginate in the same bowls. The water powder ration affects the consistency and setting time of the materials and strength and quality of the impression. a thin mix will flow out of the tray and away from the tissues with increased tear risk. a thick mix will capture less fine detail. Ideally work with a predetermined amount of powder and alter the water. Primary mechanisms of alginate distortion is water absorption (imbibition-Do not wrap in wet paper towels or immerse in liquids) and evaporation of liquids (syneresis occures even at 100% humidity). Distortion exists if impressions are not poured up within 12 minutes of removal. Alginate can stick to teeth (hydroxyapatite)