Physiological and Immunological Changes Associated with Oral Microbiota When Using a Thermoplastic Retainer.

: The study examined the oral microbiota, physiological and immunological changes in patients using thermoplastic retainers during three months of use. : The study included several steps. Firstly, 10 swabs were collected from the buccal and palatal surfaces of the teeth of the patients, approximately 2 mL of saliva was collected from the same patients and 2 mL of saliva was collected from 10 healthy people to measure the pH and secretory IgA level. This was followed by the isolation and identfication of the bacterial isolates in the patient samples. Then, isolate susceptibility toward chlorhexidine (CHX) and their adhesion ability to thermoplastic retainer surfaces was measured. In addition to that the study estimated the numbers of and colonies during three months and finally, a comparsion of pH acidity and IgA level between the patients and healthy people was performed. The results showed the predominant bacteria during the three months were spp. and spp. followed by different rates of other bacteria. showed more resistance to CHX while spp. showed more sensitivity. colony levels were higher than spp. colonies during the three months, also . had the highest value in adherence to retainer thermoplastic. Finally, pH acidity showed a highly significant difference ( ≤ 0.05) in the third month, like IgA levels ( ≤ 0.05). : According to the results obtained from the current study, the researchers noted that the thermoplastic retainers helped change the oral cavity environment.