A trip to the dentist probably doesn't rank high on anyone's to-do list. Now, imagine if your dentist skimps on appropriate amounts of anesthesia before submitting you to painful procedures.

That's just one of the things California Attorney General Bill Lockyer is alleging in criminal complaints against 20 dentists throughout the state. He's charging them with defrauding the state Medi-Cal System of $4.5 million, health benefits and workers' compensation fraud, conspiracy, grand theft, child abuse, elder abuse, assault and intentional infliction of great bodily injury.

"These dentists put at risk the health and well-being of hundreds of children and adults by performing slipshod dental services that were unnecessary and ignoring health problems that needed tending," Lockyer said.

The complaint charges Modesto dentist Kyon Maung Teo, who owns Hatch Dental clinics in Ceres, Stockton and Modesto, with being the mastermind of a scam involving dentists from throughout the state. The complaint alleges Teo placed ads on the back of missing-children flyers and in PennySaver and DollarSaver publications offering gifts or rebates to Medi-Cal beneficiaries and "new patients" who sought services at Hatch Dental.

The investigation showed Teo recruited 19 other dentists, who were paid about 25 percent of the insurance proceeds received by Hatch Dental for the work they performed. The alleged kickbacks provided an incentive to perform unnecessary dental procedures of poor quality, including unnecessary fillings and even unnecessary root canal procedures.

It was not uncommon for a patient to walk out of Hatch Dental with 20 or more unnecessary fillings, Lockyer charged. To help increase billings, dental assistants also were instructed to perform procedures such as cementing crowns, which lawfully can only be performed by licensed dentists.

Co-defendant Kin Thor Pang, Teo's wife, was the office manager for all three Hatch Dental clinics. The complaint alleges she trained office staffers to complete false dental claims, including changing dates of service or billing Medi-Cal and private insurance companies for "emergency" office visits if the patients were ineligible for routine coverage at the time of service.

The Hatch clinic staffers were also were trained to fabricate periodontal charts and prepare Treatment Authorization Requests (TARs) to obtain Medi-Cal reimbursement for services based on the fabricated charts, Lockyer said. Claims also were submitted for visits that never occurred and for non-existent procedures purportedly performed during the fabricated office visits. Insurance billing clerks were docked a dollar from their paycheck for each "mistake" they made.

As part of the conspiracy to defraud the Medi-Cal system, the dentists committed acts injurious to public health, placing the patients at risk of pain, infection, loss of teeth and great bodily injury, including: reusing dental instruments without sterilizing them, developing treatment plans that called for unnecessary dental surgeries such as root canals and fillings, performing dental surgeries without considering the patient's medical history, providing numerous shallow fillings in lieu of comprehensive treatment to patients in need of such treatment, issuing prescriptions for Schedule III narcotics without documenting the source and type of pain, forcibly restraining children during dental operations, performing extensive dental treatment on minors without fully disclosing the extent of the treatment to the minor's parent or guardian and performing dental surgeries without adequate anesthesia.