Impressions

• What type of impressions are Dental Hygienists asked to take?

  Upper and lower alginate impressions
• Why might a Dental Hygienist take impressions for a patient?

  To create diagnostic models and restorations
• What are dental impressions used for?

  Creating models, restorations, and mouth guards
• What is alginate?

  An irreversible hydrocolloid used for impressions
• What ingredients are found in alginate powder?

  Sodium alginate and calcium sulphate
• What are the reasons for taking dental impressions?

  • Primary impressions for study models
  • Accurate reproduction of teeth and structures
  • Patient education for therapies
  • Baseline recording in orthodontics
  • Monitoring tooth loss and erosion
  • Custom tray production for dentures
  • Constructing mouth guards for sports
• What are the criteria for an acceptable alginate impression?

  • All teeth included
  • Tuberosity/retromolar region included
  • Clear soft tissues of the vestibule
  • Complete palate depth
  • Features clearly demarcated
  • No air bubbles, holes, or tears
  • Properly seated and centered
  • No visible tray base or sides
  • Impression not pulling away from tray
  • Disinfected and stored correctly
• What should be included in an acceptable alginate impression?

  All teeth of the arch must be included
• Why is it important for the tuberosity/retromolar region to be included in an impression?

  It ensures complete representation of the arch
• What happens if the palate depth is not complete in an impression?

  The impression may not accurately represent the mouth
• What should be done to prevent air bubbles in an impression?

  Ensure the impression material is well mixed
• What is the consequence of not seating the tray properly?

  The impression may be uneven and inaccurate
• What should be done to ensure the impression is disinfected?

  Follow proper disinfection protocols
• What non-pharmacological techniques can help manage a nervous child during treatment?

  • Welcome appointment to acclimatize
  • Show around the dental department
  • Explain treatment using gentle language
  • Hide needles to prevent fear
  • Familiarize with instruments and trays
  • Involve parent and child in conversation
  • Regular reassurance and praise
  • Engage in light games to build rapport
  • Allow child to signal discomfort
  • Let child play with alginate
• Why is it important to avoid using traumatic language with a nervous child?

  To prevent increasing their anxiety and fear
• What should be done if a child feels uncomfortable during treatment?

  Allow them to raise their hand to stop
• What are common reasons for alginate impression failure?

  • Inadequate mixing causing air bubbles
  • Pockets of alginate powder remaining
  • Too runny or too thick alginate
  • Improper tray pressure or positioning
  • Early removal before setting
  • Presence of gross calculus on teeth
• What happens if the alginate is too runny?

  The impression may be deficient and inaccurate
• What is the effect of removing the tray before the alginate has set?

  The impression will be ruined and need retaking
• What should be done if the tray is visible on the biting surfaces?

  It indicates the tray was pressed too hard
• Why is it important to use wax along the rim of the tray?

  To ensure the sulcus is properly casted
• What can cause an alginate impression to be invalid?

  Presence of gross calculus on the teeth
• What is the consequence of having teeth off center in an impression?

  The impression will not accurately represent the mouth