Model:     Pana Max Plus
Make:      NSK
Owner:    Dr. P K Nanda

NSK Pana Max Plus is a close-casing cartridge based Air-Turbine handpiece. This particular Air-Turbine came with completely damaged cartridge. Both the front and rear end bearings were broken. Its cartridge uses ceramic bearings with Poly Amide Imide cage and Silicon Nitride balls. Most parts of the cartridge were contaminated with oxides and it needed complete overhauling with reassembling with the replacement of broken parts.

The cartridge was removed from its casing and was completely dismantled by parts. All surfaces were cleaned under ultrasonic waves and cleansed with solvent. Impeller was mounted on its original location. The Spindle-Impeller sub assembly was tested for its unbalance mass and was found to have unbalanced mass over recommended amount. It may be noted herewith that, with use, due to the natural wear and tear the rotor becomes dynamically imbalanced. Here, the unbalance mass was corrected and brought to the recommended limit of 100 µg or less.

In PANA Max Plus, unlike the earlier simplified single-port PANA Air model, water flows through two micro-irrigation channels of the casing and sprays through radially placed multiple ports. Generally, over a prolonged use, the spray-ports get partially blocked and the extent of such blockage depends on the water quality and maintenance of the instrument. Similar to the conventional lubrication of spraying lubricant through the air-duct, it is advisable to spray lubricant in the water duct (smaller of the two ducts in Borden coupling) of any multiport Air-Turbine.

A pair of pre-lubricated ceramic service radial ball bearings for NSK of Myonic GmbH make was mounted. Bur grip of spindle was lubricated. With this, reassembling of the cartridge was complete. O-ring and the wave spring washer of the casing cap were replaced. Then the cartridge was assembled into the casing. Finally, with the replacement of the spray-channel O-rings pair (Mounted across the spray channels for sealing), the repair work was completed and restored to its old functional splendour.