If the Supreme Court upholds the Affordable Care Act Thursday with no caveats, expect changes -- but don’t expect a complete overhaul overnight.

According to Dr. Toby Cosgrove, president and CEO of Cleveland Clinic, while the decision is hotly anticipated, even if the act is fully upheld it will have little effect initially on day-to-day care.

“I think most people are concerned that with the Supreme Court decision, everything will change right away,” Cosgrove told FoxNews.com. “But there’s no reason for sudden panic or fear -- change will happen over time.”

The law, which will expand coverage to 30 million Americans without insurance, will be set into place over a period of five to 10 years. A few of its main tenets include mandating the purchase of heath care coverage (and penalizing those without), outlawing denial of coverage based on pre-existing conditions and expanding Medicaid.

“The law was designed to increase access for people without coverage, lead to greater transparency and improve the quality of care,” Cosgrove said.  “Our health care system was designed in the 1950s and '60s, and huge changes have occurred since then.”

These changes notably include a large shift in demographics as the ‘baby boomer’ generation ages into their senior years.  “Over 10,000 people a day become 65,” Cosgrove said.  “...It’s a new population.”

Going along with the demographic change, Cosgrove said there has also been a distinct shift in the types of illnesses people suffer from in the past couple decades. Where once people mostly suffered from 'acute' or short-term illnesses, there has been a flux of people in recent years who suffer from chronic health conditions such as Type 2 diabetes or emphysema.

"These are the diseases that come from lifestyle choices, such as obesity and smoking," Cosgrove said.  The law aims to tackle these problems by focusing on preventive medicine.

"One of the components of the reform is the incentive to look after patients across the entire continuum of health care," he said.  "Doctors would be paid not based on procedures done, but on keeping people healthy and trying to keep them out of the hospital -- so essentially you're removing pay for volume in favor of pay for value. That's gradually spreading across the country right now."

Another main component of the reform is streamlining hospitals into large systems reaching across the country.  Cosgrove said this newfound collaboration between hospitals is meant to encourage an integrated system, where a patient can benefit from more coordinated care.

"A patient who is sick and discharged from the hospital will continue to receive help and be moved to an appropriate rehabilitation center, so that organized care will continue," Cosgrove said.  "It's all interwoven by electronic medical records, so you will have access to higher quality care."

However, a second expert who spoke with FoxNews.com expressed serious reservations that the reform could achieve its expressed goals.

According to Dr. Jane Orient, executive director of the Association of American Physicians and Surgeons, as well as a long-time practitioner of general internal medicine, the reform is likely to do greater harm than good for doctors and patients.

"One thing that may happen, first of all, is that your doctor might not even be there any more because a high percentage of physicians have said they cannot afford to or simply will not practice under these new regulations," Orient explained.  "Many are already selling their practices and joining big hospitals and clinics."

Orient said her main concern with the reform is she believes it focuses on saving money, rather than improving the patient's experience at the doctor's office. "You'll see doctors doing fewer tests, scheduling fewer visits or having patients see nurse practitioners instead -- these are the main cost saving mechanisms," she said.

Orient added that pilot programs for preventive medicine have shown little improvements in money saved, but have had a "profound, negative effect on how patients are treated."

"Preventive medicine is presumably supposed to save money 20 years from now, but there's no evidence this will happen," Orient said. "Most projects for treating blood pressure or diabetes aggressively spend more than they save -- and there's lots of money diverted into these efforts, but that money's coming out of acute treatments, so we're treating sick people less and less.

"I don't think that's what most people want," she added. "They want what's the best possible treatment for themselves or their family."

The groups most at risk of suffering a decline in care are "senior citizens, people who tend to be sicker, even young children because the emphasis is on people in their most productive years of life," according to Orient.

Among the potential negative impacts on treatment, Orient listed longer wait times to see the doctor, limited access to specialists, 'group visits' because doctors don’t have time to see patients one-on-one, and diminished freedom of choice for patients.

“A lot of people think oh goody, all these things are free, but it still comes with a price,” Orient said. “You will get whatever the system thinks you should have.”

Orient said the changes would likely be devastating to close doctor-patient relationships. "That's the very worst feature, the destruction of the doctor-patient relationship," she said.  "It doesn't support compassion or dedication to doing your very best; instead it's about checking off boxes."