Monitors display SmileDirectClub Inc. signage during the company's initial public offering (IPO) at the Nasdaq MarketSite in New York, U.S., on Thursday, Sept. 12, 2019.

The California disciplinary process underway against dentist Jeffrey A. Sulitzer, SmileDirectClub's chief clinical officer, is the latest threat facing the high-flying teledentistry firm, which promises to straighten Americans' teeth without a visit to an orthodontists office for costly treatment.

The top dentist and public face of SmileDirectClub is at risk of losing his California license following a two-year state dental board investigation, records reviewed by Reuters show.

SmileDirectClub sells clear plastic dental aligners prescribed by doctors who review digital images of customers' teeth online and oversee treatment from afar. According to the company's website, Dr. Sulitzer leads all SmileDirectClubs licensed dentists and orthodontists, a network it says includes 250 medical professionals.

In a formal 24-page complaint filed by the office of Californias Attorney General and prepared by the state dental boards executive officer, Sulitzer is accused of violating state law, defrauding state dental regulators and acting with gross negligence toward patients while helping SmileDirectClub grow its business.

See the California disciplinary accusation: here

The document cites nine different causes for discipline. For instance, it alleges Sulitzer committed fraud when applying to operate dental offices in California and assuming liability for services offered to patients. In fact, the complaint says, the locations were controlled by SmileDirectClub, which isn't licensed to practice dentistry in the state and requires customers to sign liability waivers before getting treatment.

It accuses Sulitzer of aiding and abetting the company in the unlicensed practice of dentistry and seeks the revocation or suspension of his 16-year-old California dental license.

Asked by Reuters about the California disciplinary process against its lead dentist, the company declined to make Sulitzer or other company representatives available for an interview on Tuesday.

J. Erik Connolly, the company's external litigation counsel in Chicago, wrote in an email that the accusations against Sulitzer are factually inaccurate, and will be proven false in the course of the process.

Connolly accused California Dental Board members of using the disciplinary process as a retaliatory measure, after SmileDirectClub and Sulitzer sued them last year for allegedly engaging in an illegal investigation and anti-competitive campaign against the company.

SmileDirectClub does not engage in the practice of dentistry as the California accusation asserts, Connolly wrote, calling the complaint against Sulitzer a farce.

In a separate press release Tuesday, the company noted that Floridas dental board had closed its own investigation into SmileDirectClubs business last month, and said it was the 18th U.S. state to reject unevidenced complaints about the company.

The company says its teledentistry platform connects customers with independent doctors who can approve and oversee aligner treatment. It is the state-licensed dentists who are responsible for all aspects of clinical care, the release said.

Californias Department of Consumer Affairs told Reuters the complaint against Sulitzer filed in Sacramento on November 12 is expected to lead to a formal disciplinary hearing by the state's Office of Administrative Hearings, which has yet to schedule it. Attorney General Xavier Becerra's office, which represents the department and the dental board, declined to comment.

Nashville-based SmileDirectClub says its $1,895 direct-to-consumer aligners cost 60% less than traditional braces. The company's $5 billion market capitalization is one sign Wall Street sees it as an industry-disruptive force.

Yet regulators and dental trade groups have questioned the safety of a SmileDirectClub process that doesn't require doctors who prescribe its aligners to conduct oral examinations on patients before treatment.

U.S. customers begin with an interview and digital dental scan at one of the company's nearly 380 Smile Shops nationwide, or by sending the company a dental impression kit. Later, a SmileDirectClub-affiliated dentist or orthodontist can review a patient's information and dental images online and approve aligner treatment when appropriate. The company's website quotes Sulitzer as saying its customers receive the same level of care as patients who visit traditional orthodontists.

A Reuters review found nearly 60 complaints about SmileDirectClubs aligners to the U.S. Food and Drug Administration from clinicians or customers, some alleging negative outcomes including loose or lost teeth, jaw pain, bite misalignments, and the need for costly follow-up treatment.

Connolly, SmileDirectClub's lawyer, said the complaints account for a small fraction of the 750,000 patients who've been treated with its aligners. That treatment, he said, is as safe or safer than the treatment received by traditional brick-and-mortar dentistry, he wrote.

SmileDirectClub has attributed much of the criticism to a U.S. dental lobby intent on derailing its success. Its website features thousands of positive customer reviews, and the company says less than 1% of its customers have had any clinical concerns during treatment.