Doctors

William M. Egan DMD

Dr. Egan graduated in 1973 from Tufts University with high honors. In 1982 he graduated from the University of Connecticut School of Dental Medicine with awards for attaining the "Highest Scholastic Standing", "Excellence in Sciences" and "Excellence in Leadership". Dr. Egan is a member of the American Dental Association, Massachusetts Dental Society, Worcester Dental Society, and Metro West Dental Society. Dr. Egan has been treating patients at Southborough Dental Associates since 1982. He has a simple philosophy which is to perform the highest quality of dentistry he can with the patient's best interest at heart. Outside of the office Dr. Egan enjoys golfing, skiing, running surfing and spending time with his family.



Andrew P. Zaterka, DMD

Dr. Zaterka graduated from St. John's in Shrewsbury in 1986. He attended Tufts University and Tufts Dental School, graduating at the top (13th out of 156) of his class in 1994. After a short period in Fitchburg and Concord NH, Dr. Zaterka joined Southboro Dental in 1997, and became a Partner in 2000. Dr. Zaterka is a member of the American Dental Society, the Massachusetts Dental Society and the Worcester Dental Society where he is a volunteer for patients without access to dental care. He is one of the few dentists certified in both Invisalign (Preferred Provider) and Six Month Smiles, and has a dual concentration in oral surgery and porcelain esthetics in his post-doctoral education. Dr. Zaterka has been recognized as a top Dentist in the Northeast by the IAD, and on a local level by the Metrowest Reader's Choice Awards. Dr. Zaterka grew up in Northborough and now resides in Southborough with his wife and three children. Dr Zaterka's practice philosophy is very simple: "Give every patient 100%."


Karen L. Madruga, DMD

Dr. Karen L. Madruga is an owner of the Southborough Dental Associates. Where her philosophy is to maintain integrity, compassion and a gentle touch while delivering results.
Current concentrations consist of restorative dentistry, including implant restoration and complex smile design, challenging aesthetic cases, and Top Tier Invisalign ® dentistry with the help of but not limited to accelerated orthodontics. She is also proficient in administering Botox ® and Dermal Fillers.
Dr. Madruga earned her degree in Health and Sciences at Northeastern University and became a Registered Dental Hygienist at Forsythe. Furthering her education, she graduated with her Doctor of Medicine in Dentistry at BU Goldman School of Dental Medicine in 1999, giving her over two decades of experience in her field. She completed her postdoctoral training with Veterans Medical Center and Jackson Memorial Hospital. Wanting to help communities in need, Dr. Madruga has also gained experience in missionary dentistry in Guayaquil, Ecuador.
She maintains membership in the American Academy of Clear Aligners (AACA) and is a selected member in David Galler's Reingage through align technology. Together with her group she has won awards for top Invisalign Doctor in Northeast America. Through this program she attends courses quarterly to achieve the highest quality of care with Invisalign ® and other areas of aesthetic dentistry to her patients. To stay up to date in her field, she remains a professional member of the American Dental Association and The Massachusetts Dental Society.
What sets Dr. Madruga apart from other top dentists is her ability to deliver the best Dentistry possible to her patients on a consistent basis.

"What People are saying:"

  • Linda - "Excellent dentist and superior Invisalign ® specialist. Cares about her patients."
  • Adam - "A good dentist is hard to find."
  • Juneo - "Dr. Madruga is a true professional, with expert knowledge on all aspects of dentistry..."
  • Deb - "Always a great experience! I highly recommend Dr. Madruga."

Awards & Certifications:

Adam H. Robbins, DMD

Dr. Robbins joined the Southborough Dental Associates team in 2019. He graduated cum laude from the Boston University Henry M. Goldman School of Dental Medicine in 2015, and received an Sc. B in Biology from Brown University in 2009. Currently, he is a member of the American Dental Association, the Massachusetts Dental Society, and the Worcester Dental Society. Dr. Robbins's philosophy as a clinician emphasizes compassion and patience; his favorite days are when he can make a once-nervous patient look forward to their next visits.
Dr. Robbins lives in Shrewsbury with his wife, their son, and their energetic Belgian shepherd, Lobo. He enjoys reading (ask him for a good recommendation!), photography, and hiking with his family.


Hygienists