Characterization of oral films formed in the presence of a CPP-ACP agent: an in situ study.
OBJECTIVE
The aim of this study was to compare the morphological appearance and the molecular composition of intraoral integuments formed in situ on germanium (Ge) crystals in the presence or absence of the commercially available casein-phosphopeptide-amorphous calcium phosphate (CPP-ACP) cream agent.


METHODS
Six volunteers participated in the study. Impression of maxillary arch was taken for each patient, and a removable orthodontic appliance with a custom-made retainer was fabricated. Clean Ge crystals mounted in the retainers were placed intraorally for 30 min, 8, 24 h and 1-week period. The free sampling surface of another series of Ge crystals was treated with the commercial CPP-ACP agent (Tooth Mousse), mounted in the retainers and placed intraorally for the same period as above. The free exposed surfaces in oral cavity of the specimens in all subjects were examined as follows: (a) reflected light microscopy, (b) micro-MIR-FTIR spectroscopy and (c) scanning electron microscopy (SEM) plus energy-dispersive X-ray microanalysis analysis (XEDS).


RESULTS
The light microscopic observations revealed that there was a delay in biofilm formation on Ge surfaces treated with agent in comparison to those ones without treatment. The micro-MIR-FTIR spectra from the surfaces with Tooth Mousse showed an increase in intensity and a left shift of PO(4)(3-) peak (1064 cm(-1)). Finally, the PO(4)(3-) peak at lower bands (564 cm(-1)) and the low-wave bands at 525-530 cm(-1) increased at 1-week interval. The SEM revealed the dendritic development of microbes. The XEDS analysis showed a significant increase in Cl/O, K/O, K/Cl and a decrease in Ca/O and P/O ratios on the crystal Ge without surface treatment. On contrary, on the crystal Ge with surface treatment an increase in Ca/O, Ca/P and a decrease in K/Cl ratios were found.


CONCLUSIONS
The results show that the presence of CPP-ACP agent delays the biofilm formation and favored the nucleation and crystallization of calcium phosphates, possibly in apatitic form, in matured biofilms.
Rahiotis
Christos
C
Section of Basic Sciences and Oral Biology, Department of Oral Biology, School of Dentistry, University of Athens, 2 Thivon Street (Goudi), 115 27 Athens, Greece. craxioti@dent.uoa.gr
Vougiouklakis
George
G
Eliades
George
G
D000328:Adult; D018441:Biofilms / Q000187:drug effects*; D002130:Calcium Phosphates / Q000032:analysis; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002364:Caseins / Q000008:administration & dosage / Q000627:therapeutic use*; D003460:Crystallization; D003773:Dental Plaque / Q000737:chemistry / Q000188:drug therapy*; D004577:Electron Probe Microanalysis; D005857:Germanium; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D017550:Spectroscopy, Fourier Transform Infrared
D002130:Calcium Phosphates; D002327:Cariostatic Agents; D002364:Caseins; C447032:casein phosphopeptide-amorphous calcium phosphate nanocomplex; D005857:Germanium