Subjects
The subjects comprised of 28 cleft lip and cleft palate patients (19 females, 9 males), 15–31 years of age from the Orthodontic clinic, Dental hospital, Faculty of Dentistry, Prince of Songkla University. who had been undergoing treatment with fixed orthodontic appliances at least 3 months with attachments on at least 20 teeth in permanent dentition stage, no systemic disease and without orofacial clefting as part of a craniofacial syndrome, no use of systemic antibiotic or antimicrobials within the past 2 weeks, no history of milk allergy and/or lactose intolerance, no active untreated carious lesions. All of patients were informed about step of treatment and willing to participate.