Objective:To evaluate the sealing ability of the 3.0th generation of polyamidoamine dendrimer(3.0 PAMAM)on hu-man dentinal tubules.Methods:1 6 extracted premolars were cut into 2 mm thick dentin slices to establish sensitive dentin model in vitro.Then 2 samples without any treatment were selected randomly into demineralized dentin group,and the remain 1 4 dentine pills were divided into 2 groups by the random number table(n=7).Samples in the experimental group were treated with 3.0 PAMAM, those in the control group were treated with deionized water.After having immersed in the artificial saliva for 2 and 4 weeks respec-tively,the dentin slices were examined by scanning electron microscope(SEM)and X-ray energy dispersive spectroscopy(EDS). Results:SEM showed that the minerals on the surfaces of the dentine disks in experimental group were formed gradually with the time,the dentinal tubules were blocked 4 weeks after treatment.The minerals on the sample surface in control group were less and the dentinal tubules remained open.EDS results showed that Ca/P(1 .49 ±0.1 6)of mineral deposition in the experimental group was higher than that in the control group (1 .1 8 ±0.20)(P<0.05).Conclusion:The 3.0th generation of PAMAMhas the occlu-ding ability by inducing remineralization on the dentine surface and it may be used in the treatment of dentin hypersensitivity.

OBJECTIVETo evaluate the remineralization effect of Ca(OH)2 pre-treated with carboxylmodified polyamidoamine dendrimer (PAMAM) on demineralized dentin.

METHODSThirty-two demineralized dentin models were divided into four groups randomly as follows: control group with no treatment, Ca(OH)2 group pretreated with Ca(OH)2 solution, PAMAM group processed with carboxyl-modified PAMAM, and PAMAM+Ca(OH)2 group processed with carboxyl-modified PAMAM and pretreated with Ca(OH)2 solution. All samples were immersed in artificial saliva for two weeks. The remineralization effects of dentin discs were evaluated by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD).

RESULTSObserved by the SEM, it was showed that in PAMAM+Ca(OH)2 group almost all the dentinal tubules were occluded by the minerals, however this was not found in other groups. The minerals proved were hydroxyapatite through EDS and XRD tests.

CONCLUSIONSThere was potential superiority of the carboxyl-modified PAMAM with Ca(OH)2 solution in promoting the remineralization of initial dentin lesions.

Calcification, Physiologic ; drug effects ; Calcium Hydroxide ; pharmacology ; Dentin ; drug effects ; physiology ; Durapatite ; Humans ; Microscopy, Electron, Scanning ; Polyamines ; pharmacology ; Random Allocation ; Saliva, Artificial ; X-Ray Diffraction