Middle-market private equity firm MidOcean Partners has purchased a majority stake in Affinity Dental Management Holdings LLC, an administrative services company for the dental industry.

Affinity was established in 1999 when Dr. Craig Saltzman opened his first dental office. Through multiple affiliations and new practice openings, Affinity now operates as a network of dental practices focused on providing “superior patient care.” The target offers management and administrative support services for dental practices to focus their efforts on clinical procedures. Affinity services multiple practices across Western Massachusetts, Connecticut and Vermont.

Affinity “operates a services business with a retail-based model focused on site growth and the consumer experience, areas where MidOcean believes it can add significant value,” according to MidOcean managing director Elias Dokas. Financial terms of the deal were not disclosed.

Established in 2003, MidOcean is a middle-market PE firm that targets multiple sectors, including: consumer, industrial and business services. The New York-based PE firm sold Agilex Fragrances to Firmenich in June, which it bought in December 2012. The firm also sold Penton to Informa plc, a U.K. based business information provider. Some of the firm's previous investments include: maker of skincare moisturizer Image Skincare, luggage company Travelpro Group, and kids play set manufacturer KidKraft. MidOcean provides a minimum of $25 million in equity in its deals.

Other middle-market deals involving the dental and medical industry includes: Dentsply International Inc's $5.5 billion deal to buy Sirona Dental Systems Inc.; private equity firm Cressey & Co. LP's investment in Dental Services Group; and Gryphon Investors deal to form OneSmile LLC, a dental services organization.