A Handpiece Built to Do One Job Well

The Lares Pastel Plus Prophy handpiece is a low-speed, air-driven unit designed specifically for cleaning and polishing teeth; it isn't built to hold a bur or diamond, only ADA- and ISO-compliant reusable or disposable prophy angles and Doriot attachments. That narrow purpose means there's a shorter, more specific list of things that actually fail on it compared to a high-speed handpiece, and Lares' own instructions for use document exactly what they are.

Specification	Value
Weight	1.6 oz (47 grams)
Length	3.9 in (9.9 cm)
Speed	2,500 rpm at 40 psi (2.8 bar)
Connection	'MidWest' style 4-hole (ISO 9168 Type 2)
Air consumption	45 NL/min at 40 psi
Recommended air pressure	40 psi (range 32 to 40 psi)
Warranty	2 years from date of purchase

What Actually Fails

Symptom	Documented Cause
Handpiece stalls	No or low air pressure at the supply tubing
Handpiece stalls	Supply tubing not fully and properly seated against the gasket
Handpiece stalls	A dry motor from insufficient lubrication
Handpiece stalls	A damaged or defective prophy angle
Handpiece stalls	A worn backend gasket
Handpiece stalls	Pinched supply tubing
Nose cone won't swivel effectively	Debris stuck in the nose cone mechanism

Notice that every documented failure mode in Lares' own troubleshooting table falls under a single overarching symptom: the handpiece stalls. That's a useful thing to know before assuming a complex internal fault; most causes are simple to check chairside.

Diagnosing Before You Call for Service

Check that supply tubing is properly engaged and not blocked or pinched anywhere along its length.
Reconnect the handpiece to the supply tubing, confirming full contact between the handpiece and gasket.
Inspect the backend gasket for visible damage or wear.
Confirm the prophy angle isn't damaged or defective try a fresh one before assuming a handpiece fault.
If the motor seems dry or sluggish, follow the documented lubrication steps before assuming a mechanical failure.
If the nose cone won't swivel freely, apply lubricant to the tip and manually rotate it to work loose any stuck debris.

dental handpiece oring on Repair Guru

What Happens If Chairside Steps Don't Work

Lares' own instructions are specific here: if lubricating and manually rotating the nose cone doesn't resolve a swivel problem, the device should be returned to the factory for repair and the nose cone should not be removed by the user. This is one of the few Lares handpiece lines where the manufacturer explicitly discourages attempting further disassembly at all, which shapes how a repair request should be framed.

Print Shipping Label Track Your Repair

Repair routing

For authorized repair, send the handpiece directly to Lares Research (U.S.A. only), shipping prepaid. Outside the U.S.A., handpieces go to your authorized Lares distributor.

Replacement Parts and Accessories

Item	Item Number
4-hole gasket	10009
One-Step Handpiece Conditioner	10083
Lubrication nozzle	10361
Repair return pouch	10420

When Professional Repair Is Required

Stalling persists after checking air pressure, tubing connection, gasket condition, and prophy angle
The nose cone won't swivel effectively even after lubrication and manual rotation
A backend gasket shows visible damage that a replacement doesn't resolve
Any performance issue not explained by the causes listed in Lares' own troubleshooting table

Preventive Servicing

Lares recommends sending the Pastel Plus back to the factory for service every 300 autoclave cycles or one year, whichever comes first, a useful planning benchmark for a hygiene department cycling several units through daily sterilization.

Frequently Asked Questions

Can I remove the nose cone myself to clear a stuck swivel?

No. Lares' own instructions are explicit that the nose cone should not be removed by the user. If lubrication and manual rotation don't free it, the correct next step is factory repair, not further disassembly.

Is stalling always a lubrication problem?

No. Lares lists six separate documented causes of stalling, from air pressure and tubing issues to a damaged prophy angle or worn gasket. Lubrication is only one branch of that troubleshooting tree.

For more insights on professional dental equipment repair, please visit Repair.Dental or follow us on Facebook & Instagram.

Pastel Plus Prophy Repair Guide | Repair.Dental