WARWICK -- The state Department of Health yesterday suspended the license of a Warwick dentist who allegedly slapped an 8-year-old patient across the face on Sept. 12.

The ruling, by Health Director David R. Gifford, went into effect yesterday at 5 p.m., indefinitely prohibiting Dr. Steven M. Kenyon from practicing dentistry.

"It's very serious," Gifford said in an interview yesterday. "I wanted to make sure that this type of behavior does not happen to any other child."

The decision came five days after Kenyon, 49, of Coventry, pleaded not guilty in District Court to a single count of simple assault. He was released pending a Nov. 7 pretrial conference.

In justifying his summary suspension order, Gifford cited a complaint from the 8-year-old's mother and telephone calls from the Warwick Police Department and a dental hygienist in Kenyon's office at 2212 Post Rd. Gifford said Kenyon, a 1982 graduate of the Tufts University School of Dental Medicine, also verbally assaulted his patient during the incident.

The boy's mother told the police that Kenyon had been the family's dentist for 12 years when she brought her son in suffering from a toothache and an abscess. The pain had kept the boy awake and, in Kenyon's office, the boy made no secret of his discomfort.

Kenyon administered three shots of a painkiller to numb the left side of the boy's face. When the boy continued to complain, Kenyon verbally chastised him and slapped him across the face, his mother told the police. During the procedure, the boy sat up screaming in the dental chair, prompting Kenyon to forcefully thrust him down, his mother said. He later plugged and twisted the boy's nose with his hand, the police report says.

Kenyon's alleged behavior -- he is accused of yelling "Shut up!" and uttering repeated expletives to the wailing child -- apparently dismayed Dawn McConnell, a dental assistant who has worked in Kenyon's office for 4 1/2 years and who witnessed the altercation.

"She was so shocked by Dr. Kenyon's behavior that she burst into tears two hours after the victim left the office," police detectives wrote after interviewing McConnell. "She has never seen anyone act so unprofessionally and demonstrate such a lack of patience."

Kenyon's lawyer, C. Leonard O'Brien, said he had not seen Gifford's order yesterday. He declined to comment or make his client available for an interview. "Although I am aware there has been an order issued, I have not read it," he said. No one answered the telephone at Kenyon's office late yesterday; the recording said the office would reopen at 8 a.m. today.

The Board of Examiners in Dentistry, which oversees the investigation of complaints, has disciplined about 40 dentists since 1991. It has placed several dentists on probation and reprimanded others, but only about 10 dentists have had their licenses suspended in the last 14 years, Department of Health spokesman Robert Marshall said.

The dental board will hold a hearing Wednesday to discuss the recent allegations of misconduct. The board -- made up of dentists, dental hygienists and members of the public -- could recommend a range of measures, including revoking Kenyon's license. "Dr. Kenyon still has due process available to him," Marshall said.

For now, Gifford said reasonable parents might be hesitant to send their child to Kenyon for fear of a similar occurrence. For that reason, he said, an immediate suspension was in order.

"That meets the definition to do a summary suspension," Gifford said. "It was based on asking the question: Can I wait through a normal process for it or not?"

Benjamin N. Gedan can be reached at bgedan [at] projo.com