Ceramic Application & Contouring Flashcards

A ceramist is building a lower molar crown and must recreate the Curve of Spee in the ceramic occlusal surface. Which anatomical feature guides this determination?

Answer: The anteroposterior curvature of the mandibular arch from canine to second molar

The Curve of Spee follows the anteroposterior arc of mandibular posterior teeth; the ceramist references opposing and adjacent teeth to match this curvature in the restoration.

When applying dentin ceramic, the appropriate liquid-to-powder ratio for optimal brushability and minimal air incorporation is best described as:

Answer: Firm paste that holds its shape but flows slightly when vibrated

Dentin ceramic mixed to a firm, slightly moist paste can be shaped with a brush and condensed by vibration to eliminate air voids without slumping.

What technique is used to prevent ceramic slumping on steep axial walls during the build-up phase?

Answer: Use a thicker mix and apply in horizontal increments, allowing partial setting between layers

Applying thicker-consistency ceramic in horizontal increments and blotting excess moisture between additions allows each layer to support the next without slumping.

Which staining technique adds surface characterization to a ceramic restoration after initial glaze firing?

Answer: External surface staining fired at low temperature after glaze

External stains are low-fusing colorants applied over the glaze surface and fired at reduced temperature to add surface characterization like hypocalcification spots or incisal effects.

When matching the contour of a ceramic crown to its natural adjacent teeth, the ceramist should evaluate the restoration from which viewing perspective first?

Answer: Facial view at eye level to assess height, width, and emergence profile

The facial/labial view at eye level reveals overall proportions, smile line position, and contour symmetry, making it the primary initial assessment perspective.

A ceramist notices micro-cracks on the surface of a zirconia crown after ceramic layering. The most likely cause is:

Answer: Thermal shock from uneven heating or cooling rates during firing

Zirconia has low thermal conductivity; uneven or rapid temperature changes create differential stresses that manifest as surface micro-cracks in the veneering ceramic.

The 'hold time' at peak temperature during ceramic firing is important because it allows:

Answer: Full sintering and maturation of ceramic particles without additional temperature increase

Holding at peak temperature ensures complete sintering, particle bonding, and color development without requiring higher temperatures that could overfire the ceramic.