- 0483

Technical Hotline Germany +49 60 07/91 76-222

www.wieland-international.com

Instructions for Use

1

Contents

Indication PressX Muffle p. 2

Indication PressX™ ZR p. 2

Contra-Indication PressX™ ZR p. 2

Design of the substructure p. 3

Required substructure dimensions p. 3

Press ceramic thickness p. 4

Determine the number of press pellets necessary p. 5

Choose the correct muffle size p. 5

Choose the correct disposable plunger former p. 6

Positioning the disposable plunger formers p. 7

Spruing press objects up to 6 unit-bridgework p. 8

Choose the correct disposable plunger p. 9

Investment suggestion chart p. 10

Investing and preheating p. 11

Pressing process p. 11

Devesting p. 12

Separating of the plunger connectors and the sprues p. 12

Troubleshooting p. 13

Important!

The following „PressXMuffle Instructions for use“ is a supplementary information. Please also

follow the recommendations given in the “PressX ZR Instructions for use”.

2

Indication PressXMuffle

The PressXMuffle is made of precisely milled sections (top, base and sides), that can be

assembled to 100g-, 200g- or 380g-muffles and which are held together by two aluminum

rings. One large advantage of this muffle system is the individual placement of one to five

plungers. This enables the use of five different shades and up to 20g of ceramic during one

pressing process.

Indication PressX ™ ZR

� To press over zirconium oxide (ZrO2) substructures (single crowns, bridgework up to 6

units, inlaybridges, abutments), preferable ZENO® ZR, with a CTE 25-500°C of 10,5*10 -

6K-1 using the layering or staining technique.

� For fully pressed contoured inlays, onlays and veneers without a ZrO2 substructure use

only the staining technique.

Contra-Indication PressX ™ ZR

� To press over zirconium oxide substructures not within the CTE range

� To press over bridgework > 6 units

� The substructure must fit without friction on the die

� Veneering of zirconium oxide substructures with defects like microcracks or perforations

� Crowns or bridges without a zirconium oxide substructure

� Using the layering technique for inlays, onlays and veneers without a zirconium oxide

substructure (further veneered with ZIROX® Dentine and Incisal)

� Using a Liner before the press process

� Use of other veneering material than ZIROX®

� Improper preparations

� Lack of veneering space

� For patients with parafunctions (e.g. bruxism)

� Patients with severely reduced residual dentitions

� Heavy adjustment of fit with rotary instruments at high pressure and high speed without

water cooling by dentist or dental technician

3

Design of the substructure

� The ZrO2 substructure must necessarily be designed in an anatomical form and in

particular, support the press ceramic WZO and the veneering porcelain in the incisal and

occlusal area.

� The substructure must fit without on the die.

� Excessive loss of substance must be compensated for by the framework and should

never be buffered by using press and veneering ceramic.

� The connectors must also be designed according to certain rules:

o In order to maximize the mechanical strength a vertical alignment is indicated.

o In the posterior region the minimum diameter of the connector must be 9.0 mm²

and in the anterior region 7.0 mm².

� The design of the pontic must allow enough space for the press ceramics to flow through

the basal areas. For this reason a collar should not be used on the pontic.

Required substructure dimensions

� ZrO2-Substructures ≤ 3 units: 0.6 mm wall thickness � bridgework 4 – 5 units: 0.6 mm wall thickness + reinforcement � bridgework 6 units: 0.8 mm wall thickness

Note!

The minimum wall thickness for 4 – 5 unit bridges must be 0.6 mm. In addition we

recommend for reasons of stands stability the abutment teeth something to be strengthened.

4

Note!

Please also check the instructions for your current substructure and follow these

manufacturers’ guidelines. We highly recommend ZENO® ZR, please always follow the

recommendations given in the instructions for use.

Press ceramic thickness

� Ceramic pressed over a zirconium oxide substructure must have a minimum thickness of

0.6 mm, especially at the marginal edge and under the pontic, in order to assure

complete over pressing.

� Also very important for the strength of the restoration is to assure that the occlusal and

incisal areas all have a porcelain (pressed or layered) thickness minimum of 1.0 mm and

a maximum of 2.0 mm. In the basal area the thickness of the porcelain should be 1.0 mm

up to 1.5 mm.

Important!

Not following the guidelines may cause chipping, cracking or complete restoration failure.

Fig.3 : Design of a 3-unit bridgework.

5

Determine the number of press pellets necessary

In order to determine the number of the press pellets necessary, the exact weight of the wax

and PMMA, including the pressing sprues, is required. First weigh the zirconium oxide

framework and then build up the anatomical form in PMMA and wax and weigh again

(including sprues). The difference is the specific wax weight.

Now calculate the number of pellets needed.

Weight of wax < 0,5g 0,5 – 1,1g

1,2 – 1,7g

1,8 – 2,3g

2,4 – 2,9g

3,0 – 3,5g

3,6 – 4,1g

4,2 – 4,7g

4,8 – 5,3g

5,4 – 5,9g

Number of press pellets

1 2 3 4 5 6 7 8 9 10

Weight of PMMA (CAO)

< 0,5g 0,5 – 1,1g

1,2 – 1,7g

1,8 – 2,3g

2,4 – 2,9g

3,0 – 3,5g

3,6 – 4,1g

4,2 – 4,7g

4,8 – 5,3g

Number of press pellets

2 3 4 5 6 7 8 9 10

Important!

When using PMMA overlay, designed by CAO, the weight will be lighter due to empty

spaces, caused by undercut areas. This has been calculated in the chart above.

Choose the correct muffle size

Choose the correct muffle size according to the size and number of objects to be over

pressed:

� 100g-muffle = max. 1 single crown

� 200g- muffle = max. 4 single crowns or 1 three unit bridge

� 380g- muffle = single crowns or bridges up to 6 units; but only a maximum of 12 units

6

Choose the correct disposable plunger former

Choose the correct plunger former according to the muffle size:

Note!

Do not remove or reuse the plunger former. It will burn out completely during the preheating

process.

Fig.4: short and long plunger formers

100g-muffle = 1 short plunger former (l = 28 mm)

200g-muffle = 1 – 4 short plunger formers (l = 28 mm)

380g-muffle = 2 – 5 long plunger formers (l = 34 mm)

7

Fig.5: Positioning the disposable plunger formers

� All plunger formers must be connected with a wax wire (Ø 2.0 mm). The plunger

connectors assure optimal material flow during pressing.

� The plunger formers should be placed at a minimum of 5 mm from each other and the

muffle wall.

8

Spruing press objects up to 6 unit-bridgework

� The sprues are formed by using wax wire Ø 3.0 mm (8ga), not tapered.

� The sprues should be as short as possible (between 3 and 8 mm).

� For the 380g-muffle use long disposable plunger formers (l = 34mm).

� For the 100g and 200g-muffle use short disposable plunger formers (l = 28mm).

� Never place press objects in the center of the muffle.

� For 100g-muffle the ideal angle to the muffle base should be approx. 45 – 60°

� For posteriors the occlusal and for anteriors the labial surface of the crown must be

aligned to the outer part of the casting ring.

� The sprued workpiece is positioned on the plunger formers, ensuring a clearance of 5mm

to the edge of the casting ring and at least 10 mm of investment above the wax model.

� All plunger formers should be connected to each other with a wax wire Ø 2.0 mm (10ga).

Note!

In order to facilitate devesting, the location of the units can be marked on the bottom of the

casting ring with wax.

Fig.6: All plunger formers should be connected to each other with a wax wire Ø2.0. The sprues are formed using wax wire Ø3.0mm.

9

Choose the correct disposable plunger

� In combination with the short plunger former (l = 28 mm) in the 100g- and 200g- muffle,

use short disposable plunger (l = 36 mm).

� In combination with the long plunger former (l = 34 mm) in the 380g- muffle, use long

disposable plunger (l = 42 mm).

� Place the long disposable plunger with groove at the top.

Fig.7: Using the long plunger formers, bridges up to 6 units can be over pressed in the 380g-muffle.

10

Investment suggestion chart

Note!

Each muffle base plate fits all muffle sizes. Be sure to use only the top side. Otherwise the

muffle sides can not be attached.

Muffle size 100 g 200 g 380 g

Number of objects to be over pressed 1 single crown ≤ 4 single crown

or 1x 3-unit bridge ≤12 units and

max. 6-unit bridge

Number of shades 1 ≤ 4 ≤ 5

Disposable plunger former

short = white l = 28 mm

short = white l = 28 mm

long = transparent l = 34 mm

Number of plunger former 1 ≤ 4 ≤ 5

Number of press pellets ≤ 2 ≤ 8 ≤ 10

Ø sprue 3,0 mm 3,0 mm 3,0 mm

Sprue length 3 - 8 mm 3 - 8 mm 3 - 8 mm

Ø plunger connector ▬ 2,0 mm 2,0 mm

Disposable plunger Ø = 12mm

short = standard l = 36 mm

short = standard l = 36 mm

long with groove l = 42 mm

Minimum distance of the press object to the muffle wall

5 mm 5 mm 5 mm

Minimum distance of the press object to the top of the muffle

10 mm 10 mm 10 mm

Minimum distance of the plunger former to the muffle wall

5 mm 5 mm 5 mm

Minimum distance of the plunger former to each other

▬ 5 mm 5 mm

Ideal sprue angle 45 – 60° Do not place object in the muffle center.

Do not place object in the

muffle center.

Press program 100g-muffle 200g-muffle 380g-muffle

11

Investing and preheating

We recommend using PressX™ ZR Investment Ref. No. 87-95-00- 2500 together with the

corresponding Liquid Ref. No. 87-95-01-0500.

For information on mixing and preheating the investments, see the recommendations in the

processing instructions for the PressX™ ZR Investment.

The casting ring preheating time must be at least 60 min at 900 °C for 100g- and 200g-

muffles. For 380g-muffles preheating time must be at least 90 min at 900 °C

Important!

Do not preheat press pellets and investment plungers. Place them rapidly into the preheated

muffle and immediately start the press program.

Pressing process

The pressing process is optimized for the very unique DEKEMA Austromat 3001 press-i-

dent. Please ensure that the pressing furnace is calibrated and in correct working order.

Particularly that a continuous vacuum is maintained throughout the entire pressing process.

100g-muffle L9 C700 V9 L90 T060.C1060 T600 L95 T600 C0 L9 V0 L0 T2 C700

200g-muffle L9 C700 V9 L90 T060.C1060 T1200 L97 T900 C0 L9 V0 L 0 T2 C700

380g-muffle L9 C700 V9 L90 T060.C1060 T2400 L98 T1200 C0 L9 V0 L0 T2 C700

Important!

Firing temperatures given are for guidance only. Deviations may occur due to differing oven

performance and should be adjusted accordingly.

12

Devesting

Important!

Always let the muffle cool down to room temperature slowly. Do not use a water bath or

compressed air.

Before devesting, the exact depth of the pressed object is determined with the aid of a

second press plunger. This and the wax markings are transferred to the external surface of

the investment ring. Then the investing ring is separated at the markings with a diamond disc

and carefully separated at the resulting grooves.

The bulk of the investment can be removed by blasting with polishing agent (50µm) at 2 bar.

As soon as the press objects become visible, the blasting pressure must be reduced to 1 bar.

Separating of the plunger connectors and the sprues

� First separate all plunger connectors.

� Then the sprues can be separated from the object in the usual way.

� For further finishing of the press objects see instruction for use for PressX™ ZR and

ZIROX®.

Fig.9: First separate all plunger connectors (orange).

Then the sprues can be separated from the object in

the usual way.

13

Troubleshooting

Press failure Cause Remedy Incorrect disposable plunger former Choose correct disposable plunger former

Missing plunger connector All plunger formers should be connected to each other with a wax wire Ø2.0 mm (10ga).

Muffle preheating time too short Preheat muffle a minimum of 60 min at 900 °C

Press ceramic thickness Lower than minimum

Minimum thickness 0,6 mm

Not enough press material Increase the number of press pellets

Muffle preheating time too short Preheat 100g and 200g muffle a minimum of 60 min at 900 °C and 380g-muffle a minimum of 90 min

Object not fully pressed

Press ceramic thickness Lower than minimum

Minimum thickness 0.6 mm

Local overheating when grinding

Grind with water cooling at max 5000 U/min

Separation of the sprues before the plunger connectors

separate the plunger connectors first, then the sprues

Blasting pressure too high when devesting Devest press object at a maximum of 2.0 bar with 50 µm glass beads

Substructure not compatible with PressX ZR Use only zirconium oxide substructures with a CTE25-500°C 10,5*10-6K-1

Possible sharp edges or corners in framework

Avoid sharp edges or corners

Poor die preparation or frame design Refer to die preparation and substructure design instructions

Micro cracks and / or holes in the framework

Use only proven, defect-free substructures.

Cracks in the pressed ceramic

Incorrect Investment material Onlay use PressX™ ZR Investment

substructure to weak ≤ 3 units: 0.6 mm wall thickness bridgework 4 – 5 units: 0.6 mm wall thickness + reinforcement (Fig.2) bridgework 6 units: 0.8 mm wall thickness

Cracks in Substructure

Incorrect Investment material Onlay use PressX™ ZR Investment

Press temperature too high Lower press temperature in steps of 10 °C

Object in the muffle center Never place object in the muffle center

Sprues too long Optimal sprue length 3 – 8 mm

Wax has not been burned out completely Always use ash free wax

Bubbles in the pressed ceramic

Poor vacuum Ensure that a continuous vacuum is maintained throughout the entire pressing process

Oxide residue from metal muffle rings in the preheating oven

Be sure preheating oven is free of metal residue

Black particles in the pressed ceramic

Contaminated modelling wax Keep working area clean during modellation

Distributed by:WIELAND Dental +Technik GmbH & Co. KGSchwenninger Straße 1375179 Pforzheim, Germany

Fon +49 72 31/37 05-0Fax +49 72 31/35 79 59

www.wieland-international.cominfo@wieland-international.com

International Representations

WIELAND Dental+ Technik is worldwide represented. Find your contact person in your country under www.wieland-international.com or call us under telephone number +49 72 31/37 05-0.

5350

38e.

01.1

0/08