About Our Office

James Woltmann, DMD

Advanced Technology & Invisalign Provider

Dr. Woltmann is known for embracing technology to deliver precise, efficient, and confidence-boosting dental care. He graduated from Boston College and earned his dental degree with High Honors from Tufts University School of Dental Medicine, followed by advanced post-doctoral training.

He has trained extensively with the Pankey Institute, Dawson Academy, and Spear Education, and is a Premier Preferred Invisalign Provider. As a member of the exclusive CEREC Doctors Mentor Group, Dr. Woltmann also teaches other dentists how to perform complex procedures in a single visit.

When he’s not in the office, Dr. Woltmann enjoys time with his family and exploring the waters of the Great South Bay.

Anthony Geraci, DDS

Implant & Comprehensive Care

Dr. Geraci brings decades of experience and a deep love of science and craftsmanship to his work. A graduate of SUNY Stony Brook and SUNY Buffalo School of Dental Medicine, he completed advanced residency training and has logged over 900 hours of continuing education.

He holds fellow status in the International Congress of Oral Implantologists and has advanced training in implant placement and regenerative dentistry. Patients appreciate his thorough approach, steady presence, and long-term commitment — many have been under his care for 20+ years.

Diana Backer, DDS

Holistic & Biocompatible Dentistry

Dr. Backer focuses on biocompatible, holistic dentistry with an emphasis on health, safety, and prevention. With over a decade of experience, she blends modern techniques with a gentle, detail-oriented approach.

She trained at the University of Maryland School of Dentistry and is a member of the International Academy of Oral Medicine & Toxicology. Dr. Backer is also certified in NuCalm drug-free relaxation, helping anxious patients feel calm and supported during treatment.

Rebekah Collins, DMD

General & Cosmetic Dentist

Dr. Collins is known for her gentle touch, engaging personality, and meticulous attention to detail. Originally from Massapequa Park, she’s passionate about making dental care feel comfortable, clear, and genuinely patient-centered. She earned her dental degree at A.T. Still University in Mesa, Arizona, graduating with honors and recognition for exceptional clinical skills and leadership. Her training emphasized whole-person healthcare, including care for medically and dentally complex adults and children, and she also completed a certificate in public health with a dental emphasis.

After dental school, Dr. Collins completed an Advanced Education in General Dentistry (AEGD) program at Virginia Commonwealth University, where she received advanced training in maxillofacial prosthodontics. She practices comprehensive general dentistry and works closely with patients to choose treatments that fit their goals and lifestyle. Her clinical experience includes veneers, crowns, bridges, dentures, implant restorations, extractions, root canals, and whitening, and she is certified in Invisalign.

Alexandra Costantino, DMD

General Dentist

Dr. Costantino graduated from Molloy University with a degree in Biology before earning her Master’s in Biomedical Science from Barry University in Florida. She then received her DMD from Tufts University School of Dental Medicine. Following dental school, she completed a General Practice Residency at NUMC, where she further developed her skills in general dentistry.

Dr. Costantino is passionate about providing personalized, comprehensive dental care with an emphasis on listening, attention to detail, and patient comfort. She takes the time to understand each patient’s individual needs and goals while helping them feel informed and confident in their care. Her clinical training includes crowns, restorations, dentures, root canals, implants, and extractions.

A Long Island native, Dr. Costantino is also passionate about community outreach and mentorship. She has participated in programs including Give Kids A Smile, Tooth Day, and Special Smiles, providing oral health education and care to children and families. She has also served as a teaching assistant in multiple areas of dentistry and enjoys mentoring future dental professionals.

Outside of the office, Dr. Costantino enjoys staying active through yoga, boxing, running, and beach volleyball. She also enjoys creating unique charcuterie boards and spending time in the Long Island community she calls home.