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Troubleshooting Guide Pala Denture Acrylics
Do you have a problem when processing our denture acrylics?
Maybe you will find the answer to your question here. Or, you can contact our Technical Hotline. The contact details can be found on the right side of the screen.
Bubbles and Porosities
Errors, causes and troubleshooting
1. Mixing and filling was not void-free.
Pour the powder in steadily and quickly while stirring 30 sec. mixing thoroughly – 30 sec. saturation time.
2. Plaster model too dry
Place plaster model in lukewarm water for 10–15 min, or in a pressure pot (without pressure!).
3. Insufficient insulation, insulating layer too thick or puddles.
Apply two thin layers of Aislar insulation to the plaster model, always carefully pat off interdental excess
4. Insulating liquid doesn’t work properly.
Ensure that the expiration date has not yet occurred. Store away from light, always use fresh liquid in a separate small bowl, use a clean brush, and dispose of excess insulation. Protect the insulation from contamination (residual plaster, brush with metal ferrule).
5. Incorrect polymerisation pressure
Set pressure at 2 bar
Observe dwelling time for Paladon 65.
6. Insufficient acrylic in the filling cylinder.
Use a dosing cup.
7. Incorrect polymerisation time (premature or delayed insertion into the pressure pot)
Observe the instructions for use (extended processing periods for cold-cured polymers Palapress vario and PalaXpress)
8. Insufficient acrylic when packing (pressing) (Paladon 65).
After pressing, ensure that there are sufficient distortions available.
9. Heating up too fast (Paladon 65).
Kulzer water bath polymerisation
Basal White Discolouration
Errors, causes and troubleshooting:
1. Insufficient boiling out.
Completely clean all wax residue from the plaster model
2. Contaminated insulation.
Ensure that the expiration date has not yet occurred. Store away from light, always use fresh liquid in a separate small bowl, use a clean brush, and dispose of excess insulation. Protect the insulation from contamination (residual plaster, brush with metal ferrule).
3. (Plaster/wax) insulating material contains alcohol. Insulating material contains oil.
Do not use insulation that contains oil or alcohol.
4. Plaster/wax insulation is insufficiently dry.
The insulation on the plaster model may no longer be moist. Each insulation layer must be well-dried. Avoid puddle formation.
5. Use of inappropriate plaster type 1 or type 2, or of blue plaster.
Use Type 3 Octa Dur yellow.
6. The impression is contaminated.
The impression must be carefully cleaned to remove blood, saliva and disinfectant, etc. Rinse with clear water.
7. Boiling out units - different wax solvents.
Clean the device daily, adhere to the dosage in the manufacturer's instructions. Preferably do not use wax solvent.
8. Boiling out units - wax extraction time is too long.
Only heat the flask for about 5 minutes and remove the wax while it is still pliable, clean the plaster surfaces with plenty of clear, boiling water.
9. Plaster too cold when insulation is applied.
Extend the drying time for insulation on cold plaster.
10. Polymerisation temperature is too low.
Use the polymerisation temperatures and times prescribed in the current instructions for use.
11. Failure to observe soaking times
Use the dwelling and polymerisation times prescribed in the current instructions for use.
Irritation of mucous membranes
Errors, causes and troubleshooting:
1. Rough basal surface.
Comply with specifications regarding the handling of the impression, insulation and model fabrication; avoid excessively long evaporation and boiling out of the plaster model
2. Insufficient polymerisation time or incorrect polymerisation temperature
Cold curing acrylics 15 – 20 minutes (depends on denture acrylic), 55 °C, 2 bar. Injection procedure 30 minutes, 55 °C, 2 bar. Polymerise heat-curing acrylics in accordance with Kulzer water-bath polymerisation: heat up to 70 °C in 30 min, maintain temperature 90 min. Bring to the boil in 20, boil for 30 min, then cool slowly in a water bath.
3. Denture not stored in water after finishing.
Storing the denture in water after finishing is recommended - ideally overnight, but preferably longer.
4. Denture was recently lined.
Storing the denture in water after finishing is recommended - ideally overnight, but preferably longer, even when the patient is at home (ideally in lukewarm water).
5. Too much liquid was used. Residual monomer content too high.
Adhere to the prescribed mixing ratio.
Acrylic not completely cured
Errors, causes and troubleshooting:
1. Acrylic was placed in the pressure pot too early.
Observe the working time.
2. Water temperature too low, polymerisation time too short.
Cold curing acrylics 15 – 20 minutes (depends on denture acrylic), 55 °C, 2 bar. Injection procedure 30 minutes, 55 °C, 2 bar. Polymerise heat-curing acrylics in accordance with Kulzer water-bath polymerisation: heat up to 70 °C in 30 min, maintain temperature 90 min. Bring to the boil in 20, boil for 30 min, then cool slowly in a water bath.
3. Components may have been interchanged or the product is contaminated
Check materials to be used.
4. The expiration date has been exceeded.
Observe the manufacturing date or expiration date (powder + fluid have a shelf life of 2 - 3 years).
Poor surface quality
Errors, causes and troubleshooting
1. Insufficient insulation.
Apply two thin layers of Aislar to the plaster model, isolation must be fully dry.
2. Insufficiently clean impression.
The impression must be carefully cleaned to remove blood, saliva and disinfectant, etc. Rinse with clear water.
3. Extraction additives: surfactant and wax - example
Boil out using clear, hot water
4. Excessive boiling-out and steam-cleaning.
Avoid excessive boiling-out and steam-cleaning of the plaster model.
5. Spoiled insulation: watery, contaminated, affected by fungi
Ensure that the expiration date has not yet occurred. Store away from light, always use fresh liquid in a separate small bowl, use a clean brush, and dispose of excess insulation. Protect the insulation from contamination (residual plaster, brush with metal ferrule).
6. Porous plaster model surface
Mix plaster under vacuum
7. Plaster too hot (still steaming)
The plaster should not still be steaming (just above body temperature).
8. White spots or particles caused by condensed water during cooling of the powder in the refrigerator or excessive humidity
Store opened powder dry and at temperatures between approx. 10 °C and max. 25 °C.
Gap formation, tilting denture
Errors, causes and troubleshooting:
1. Pressure too high.
Set pressure at 2 bar.
2. Pressure pot opened during the polymerisation phase.
Observe polymerisation time in the pressure pot.
3. Excessive application of insulation
Apply two thin layers of Aislar separator to the plaster model
4. Deformation due to thermal damage of cold-cured polymers
Do not polymerise cold-cured polymers at temperatures above 55 °C.
5. Cooling too fast and flask opened too soon.
Cool down slowly (heat-curing acrylic in water bath) - deflask denture at a maximum of body temperature!
6. Substantial deviation from the specified mixing ratio
Prepare mixture according to the directions for use.
7. Intensive evaporation during cleaning.
Clean with toothbrush and toothpaste.
8. Excessive contact pressure during polishing (temperature)
Reduce contact pressure and monitor temperature
Colour deposits along the denture edge
Errors, causes and troubleshooting:
1. White streaks (finest porosities) running from the interdental spaces towards the denture base due to accumulated insulation (insulation puddles).
Always pat off excess insulation in interdental spaces; carefully remove interdental Palabond accumulations with compressed air.
2. Early injection (Palajet only)
Inject acrylic when the surface in the filling cylinder is matte and dry; avoid draughts around the vial; monitor ambient temperature (polymerisation is accelerated at higher temperatures)
3. Insufficient mixing.
Soak for approx. 30 sec., stir for 30 sec. and then pour into the filling cylinder.
4. Incorrect powder/liquid ratio.
Adhere to the dosing instructions (e.g. PalaXpress casting technique 10 g : 7 ml, injection techniques 30 g : 15 ml)
5. Bluish streaks extending out of interdental areas into the denture because a brush with a metal frame was used to apply Palabond.
Change the brush or use a brush without a metal frame if the metal is dissolved by Palabond.
Poor bonding between artificial teeth and denture base
Errors, causes and troubleshooting:
1. Failure to roughen acrylic teeth
Roughen teeth with a coarse diamond or by sandblasting (50 µm) directly before filling with acrylic.
2. Silicone coat around the denture teeth (release of silicone oil).
Use a pure plaster investment.
3. Failure to wet acrylic teeth with Palabond.
Apply bonding agent to the roughened surfaces and allow to penetrate for 30 seconds. Repeat process.
4. Excessive delay between wetting and further processing
Palabond is effective for 10 minutes after application. Further processing must occur within this period.
5. Wax or separator residue on the denture teeth.
Do not evaporate wax residue. Instead boil out with clear, boiling water; clean the denture teeth with monomer before isolation if required
Cracks and fissures
Errors, causes and troubleshooting:
1. Incorrect powder/liquid ratio.
2. Flask too hot during deflasking.
3. Rinse the flask with cold water.
4. Tension due to delayed relining
5. Premature contacts and incorrect load distribution due to tooth malposition