Objectives: Scanning Electron Microscopy evaluation of in situ chips in order to determine whether exposure to saliva can repair surface defects in four weeks.
Methods: Cores of enamel were obtained from human extracted teeth. Chips were sterilized with ethylene oxide and placed in acrylic rods and sealed with light cured composite. Enamel surface defects were created by four different methods: 1) brushed with Crest toothpaste, 2) brushed with Colgate Platinum toothpaste, 3) abraded with 600 grit abrasive paper and 4) exposed to Coca-Cola. Four chips, one from each treatment group, were bonded into a maxillary orthodontic appliance. Ten patients were recruited to wear the appliance for four weeks, 24 hours per day, removing the appliance only to eat and brush their natural teeth. The appliance was not brushed, just rinsed with water. SEM was performed before and after treatment. Samples were rated on a scale from 0-3 for in-fill of defect noted on pre-exposure to saliva.
Results: Presence of salivary pellicle was noted on 75% of samples. All samples in each of the four groups were rated in the “0” category post oral exposure (less than 25% infill of defects).
Conclusion: Salivary pellicle appeared on most samples in situ after a four week period. Enamel surface defects were not repaired by exposure to saliva in a four week period