The phones at Dientes Community Dental Care have been ringing almost constantly since California restored its dental program for low-income adults this month.

“We can’t keep up with the phones, in fact,” said Yari Alvarado, front-office supervisor. The Santa Cruz clinic has been so overwhelmed since the benefits were restored on May 1 that half way through this month the clinic placed a temporary hold on new patients until more appointment times opened up on the calendar, she said. The clinic is booked solid for the next three months.

That’s largely because for the first time since 2009, California is again paying for Denti-Cal for adults. The dental program is for low-income residents who qualify for Medi-Cal health insurance. Meanwhile, more adults qualify for Medi-Cal — and therefore Denti-Cal — after its expansion as part of the federal Affordable Care Act, which took effect Jan. 1. More than 1.9 million California residents have enrolled in Medi-Cal under health reform, and another 900,000 applications for the program are pending.

The program is fully restored to 2009 levels at some clinics and partially restored at others, depending on whether a clinic receives certain federal funding or serves a rural population. As a result, about 64 percent of clinics serving low-income and uninsured patients have returned to providing full-service dental care, said Carmela Castellano-Garcia, president and CEO of California Primary Care Association, which represents about 600 nonprofit and community health centers around the state.

“We feel it’s important for the patient to get the full range of benefits available,” Castellano-Garcia said.

In clinics where the coverage is not as extensive as it was before the 2009 cuts, teeth cleaning, cavity removal and dentures are covered, but more complicated procedures may not be. Among the treatments not covered are root canals for molars, partial dentures and a gum disease procedure.

In addition to some Denti-Cal beneficiaries not having access to all services, they may have to wait months for appointments due to the high demand. The jump in patient calls is not exclusive to Dientes or Santa Cruz County. At La Clinica de la Raza, which serves low-income patients in Alameda, Contra Costa and Solano counties, phones also are ringing incessantly.

“They’ve been getting phone calls for months,” said chief dental officer Ariane Terlet. That clinic still is taking new patients, Terlet said, but the number of requests for appointments is way up.

Castellano-Garcia said she is keeping tabs on demand at health centers around the state, as word gets out about the restored dental coverage.

During the five-year gap in dental insurance, Medi-Cal largely paid only for tooth extractions and antibiotics, said Laura Marcus, executive director of Dientes. For anything else — even a cleaning — Dientes dentists treated those without insurance for a sliding-scale fee.

Marcus expects the jump in insured adult patients at Dientes to be significant as a result of Denti-Cal benefits returning. Last year, 40 percent of those treated had basic Medi-Cal coverage, 50 percent were uninsured and 10 percent were covered through other programs, she said. For 2014, she expects 60 percent to be covered through Denti-Cal, 30 percent to be uninsured and 10 percent to be covered through other insurance providers.

The clinic does not take private insurance, Marcus said, in keeping with its mission to focus on low-income and underinsured patients.

“If you have insurance, we feel there are resources for you,” she said.

On a recent afternoon visit to the clinic, every chair in the bustling center was filled. Dentists were treating patients in chairs tucked into small nooks around the clinic, and computer servers were stacked in the bathroom. Marcus sat on a bench in the middle of it all, trying to carry on a conversation.

The vibrancy of the center was palpable, as patients seemed visibly excited to finally get work done on their teeth.

Richard Walton, 48, of Santa Cruz, said he is homeless and was about to have his teeth examined for the first time in 14 years. He made an appointment after learning about Denti-Cal from workers at a shelter.

“I want to make sure everything is OK,” Walton said, adding that he’d especially like to get a replacement for his missing front tooth.

“Then maybe I’ll get a job,” Walton said, noting that a full smile makes a better impression on perspective employers.

Dientes also plans future expansion into a new, smaller office in Watsonville and will add a dental chair at the Homeless Services Center in Santa Cruz.

The clinic takes calls from about 10 new patients seeking appointments each day, Marcus said. No one from Dientes asks about insurance during scheduling. Staff members typically don’t know until the appointment if a patient has insurance or not, she said.

While some advocates for the poor continue to argue that the Denti-Cal program should be restored in full, others are focusing on what they hope will be the benefits of the partial restoration. Assemblyman Mark Stone, D-Monterey Bay, said he hopes the restored Denti-Cal benefits will help perpetuate a cycle of regular and quality dental care.

With more adults coming in to fix their teeth, Stone said he hopes those patients see the importance of regular dental care and in turn bring their children for checkups. If kids learn good dental hygiene, they have a better chance of continuing those habits into adulthood.

“This allows us to do a lot more prevention,” Stone said.