A federal lawsuit filed in New York claims Aspen Dental Management and the private equity firm that controls it illegally operate dental clinics across the country.

The suit filed Thursday in Albany says Aspen, based in says East Syracuse, N.Y., and Leonard Green and Partners are violating laws that require clinics to be owned by dentists who actively perform procedures onsite.

Court papers say Aspen's "so-called 'Practice Owners' are nothing more than de facto employees and/or independent contractors" of the company, which controls its 358 clinics' marketing, hiring, training and bookkeeping.

Aspen says it provides management services and doesn't control clinical care. A spokeswoman says the accusations made in the filing are "entirely without merit." A message left with Los Angeles-based LGP wasn't initially returned.