Polyamide-amine (PAMAM) dendrimer, a new hyperbranched macromolecular polymer, is considered an "artificial protein" by many scholars on account of its excellent chemical and biological characteristics. PAMAM has internal cavities and a large number of reactive terminal groups. These structures allow the polymer to be used as a bionic macromoleculethat could simulate the biomimetic mineralization of the natural organic matrix on the surface of tooth tissue. Specifically, PAMAM can beused as an organic template to regulate mineral nucleation and crystal growth; thus, the polymerisa more ideal dental restoration material than traditional allogenic materials. This article reviews research progress on thePAMAM-induced biomimetic mineralization of hard tooth tissues.
Amines ; Biomimetics ; Dendrimers ; Humans ; Nylons ; Tooth Remineralization

OBJECTIVETo investigate the relationship between dentine phosphoprotein (DPP) and remineralization of demineralized dentine.

METHODS(1) Soluble DPP was extracted with 1 mol/L NaCl from demineralized dentine and was evaluated. (2) Soluble DPP was removed with 0.1 mol/L NaCl or was not removed from demineralized dentine sections in human tooth roots. Then all sections were subjected to remineralization treatment, and remineralization degrees were compared by atomic absorption spectrum, SEM and microradiography.

RESULTS(1) Soluble DPP was extracted with 1 mol/L NaCl. (2) Removal of soluble DPP resulted in significantly lower calcium concentration in remineralization solution (P < 0.01), less mean light-absorbed value in demineralized dentin sections by microradiography (P < 0.01).

CONCLUSIONSSoluble DPP may have an inhibiting effect on remineralization of demineralized dentine, this study suggests that the remove of soluble DPP from root caries lesions may enhance their remineralization potential.

Adolescent ; Child ; Dentin ; chemistry ; Humans ; In Vitro Techniques ; Phosphoproteins ; isolation & purification ; physiology ; Tooth Demineralization ; Tooth Remineralization

OBJECTIVETo evaluate the effects of casein osphopeptide-amorphous calcium phosphate (CPP-ACP) in preventing enamel demineralization.

METHODSEnamel blocks were prepared from premolars extracted from orthodontic patients. The specimens were treated for 30 min daily for 7 days with one of the following agents: deionized water (negative control), CPP-ACP paste, and NaF solutions (positive controls) (0.2% and 2%). After the treatments, the specimens were immersed in a demineralizing solution (pH 4.5) for 7 days. The morphology and depth of the lesion were observed using scanning electron microscopy, and the content of Ca, P, Mg in the demineralized enamel was measured by electron probe micro-analyzer.

RESULTSThe demineralization rates in all the treatment groups were significantly smaller than those in the control group after 7 days of demineralization.

CONCLUSIONThe application of CPP-ACP to the enamel surfaces can inhibit enamel demineralization with an equivalent effect to 0.2% NaF.

Adolescent ; Caseins ; therapeutic use ; Dental Enamel ; Humans ; Sodium Fluoride ; Tooth Demineralization ; prevention & control ; Tooth Remineralization

This study sought to determine the impact of dental fluorosis severity on demineralization and remineralization of human fluorosed teeth in vitro. Surface enamel microhardness was measured on the enamel blocks before and after demineralization and after remineralization. The results showed that after demineralization, the sequence of % Surface microhardness demineralization (% SMHD) was TFI4 (18.92 +/- 1.31) < TFI3 (20.50 +/- 1.32) < TFI2 (25.08 +/- 1.69) < TFI1 (27.77 +/- 1.79) < TFI0 (30.70 +/- 1.35) (P < 0.05), and there was no statistically significant differences between TFI1 (27.77 +/- 1.79) and the normal group TFI0 (30.70 +/- 1.35). After remineralization, the sequence of % Surface microhardness remineralization (% SMHR) was TFI1 (55.17 +/- 1.23) > TFI0 (53.97 +/- 3.05) > TFI2 (49.17 +/- 1.81) > TFI3 (44.85 +/- 1.89) > TFI4 (36.51 +/- 2.95) (P < 0.05). Moderately fluorosed enamel showed a significatnt resistance to caries, but mildly fluorosed enamel could get better remineralization. These facts and figures deserve clinicians' attention.
Dental Enamel ; chemistry ; pathology ; Fluorosis, Dental ; metabolism ; Humans ; In Vitro Techniques ; Tooth Demineralization ; Tooth Remineralization

OBJECTIVETo analyze the mechanism of fluorine by systemic analysis of fluorination-demineralization-remineralization experiments.

METHODSThe enamel specimens were randomly assigned to untreated group (group A), non-fluoride group (group B), low-fluoride group (group C) and high-fluoride group (group D). The in vitro model of fluoride enamel was established in group C and D. Based on that, the establishment of demineralization model and remineralization experiment by pH-cycling in group B, C and D were followed. All enamel specimens were observed by stereomicroscope and scanning electron microscope and compared in surface microhardness value.

RESULTSThere was distinct difference in micro-morphologic appearance on fluoride enamel surface. Artificial caries of fluoride enamel showed a relatively complete surface, the surface microhardness after demineralization and remineralization in fluoride group was higher than non-fluoride group (P < 0.05).

CONCLUSIONThe fluorinated enamel can enhance cariostatic potential and remineralization capacity of dental enamel.

Dental Caries ; Dental Enamel ; Fluorides ; Fluorine ; Humans ; Phosphates ; Tooth Demineralization ; Tooth Remineralization

OBJECTIVETo observe the effect of OHOLV on the remineralization of early enamel caries.

METHODSFifty bovine teeth with artificial early caries were divided into five groups randomly and treated with OHOLV, casein phosphopeptide amorphous calcium phosphate (CPP-ACP), NaF, OHOLV+NaF and distilled and deionized water (DDW) respectively. Then the teeth were subjected to the pH-cycling. The surface microhardness (SMH) of enamel before demineralization and after remineralization were measured by microhardness detector and the histomorphologic changes of the enamel surface were compared by scanning election microscope (SEM).

RESULTSThe SMH of all the experimental groups increased significantly after remineralization (P < 0.001). The SMH of the OHOLV group was lower than that of NaF group (P < 0.001), while there was no significant difference between the OHOLV group and the CPP-ACP group (P > 0.05). After remineralization, a large amount of comparatively large mineral particles deposited on the surface of the enamel treated with OHOLV.

CONCLUSIONOHOLV can promote the remineralization of the early enamel caries.

Animals ; Calcium Phosphates ; Cariostatic Agents ; Caseins ; Cattle ; Dental Caries ; Dental Enamel ; Tooth Remineralization

Tooth decay is prevalent, and secondary caries causes restoration failures, both of which are related to demineralization. There is an urgent need to develop new therapeutic materials with remineralization functions. This article represents the first review on the cutting edge research of poly(amido amine) (PAMAM) in combination with nanoparticles of amorphous calcium phosphate (NACP). PAMAM was excellent nucleation template, and could absorb calcium (Ca) and phosphate (P) ions via its functional groups to activate remineralization. NACP composite and adhesive showed acid-neutralization and Ca and P ion release capabilities. PAMAM+NACP together showed synergistic effects and produced triple benefits: excellent nucleation templates, superior acid-neutralization, and ions release. Therefore, the PAMAM+NACP strategy possessed much greater remineralization capacity than using PAMAM or NACP alone. PAMAM+NACP achieved dentin remineralization even in an acidic solution without any initial Ca and P ions. Besides, the long-term remineralization capability of PAMAM+NACP was established. After prolonged fluid challenge, the immersed PAMAM with the recharged NACP still induced effective dentin mineral regeneration. Furthermore, the hardness of pre-demineralized dentin was increased back to that of healthy dentin, indicating a complete remineralization. Therefore, the novel PAMAM+NACP approach is promising to provide long-term therapeutic effects including tooth remineralization, hardness increase, and caries-inhibition capabilities.
Amines ; pharmacology ; Calcium ; Calcium Phosphates ; chemistry ; pharmacology ; Dentin ; chemistry ; Humans ; Nanocomposites ; chemistry ; Nanoparticles ; Tooth Remineralization ; methods

OBJECTIVE: To investigate the effects of novel bioactive glasses (BG) including PSC with high phosphorus component and FBG with fluorine-doped element on promoting remineralization of artificial dentin caries. METHODS: (1) BGs were used in this study as follows: PSC (10.8%P₂O₅-54.2%SiO₂-35.0%CaO, mol.%) were synthesized using phytic acid as the phosphorus precursor through sol-gel method. FBG (6.1%P₂O₅-37.0%SiO₂-53.9%CaO-3.0%CaF₂, mol.%) and 45S5(6.0%P₂O₅-45.0%SiO₂-24.5%CaO-24.5%Na₂O, mol.%) were synthesized by traditional melt method. (2) The above BGs were soaked in simulated body fluid (SBF) for 24 hours. Then X-ray diffraction (XRD) was used to analyze the formation of hydroxyapatite (HA) crystals. (3) Prepared 1 mm thick dentin slices were soaked in 17% ethylene diamine tetraacetic acid (EDTA) for 1 week to demineralize the dentin. Then the dentin slices treated by BG were soaked in SBF for 1 week. Field emission scanning electron micro-scopy (FE-SEM) was used to observe the surface morphology of the dentin slices. (4) Four cavities were prepared to 1 mm depth in each 2 mm thick dentin slice, then were treated with lactic acid for 2 weeks to form the artificial dentin caries. Wax, mineral trioxide aggregate (MTA), PSC and FBG were used to fill four cavities as blank control group, MTA group, PSC group and FBG group respectively. Then the spe-cimens were soaked in SBF for 4 weeks. The changes of depth and density of demineralized dentin were analyzed using Micro-CT before filling and after 2 and 4 weeks filling. RESULTS: (1) PSC and FBG promoted mineral formation on the surfaces of the demineralized dentin. And the speed was faster and crystallinity was higher in PSC group than the FBG and 45S5 groups. (2) The increased mineral density of artificial dentin caries in PSC group were (185.98 ± 55.66) mg/cm³ and (213.64 ± 36.01) mg/cm³ 2 and 4 weeks after filling respectively, which were significantly higher than the control group [(20.38 ± 7.55) mg/cm³, P=0.006; (36.46 ± 10.79) mg/cm³, P=0.001]. At meanwhile, PSC group was also higher than MTA group [(57.29 ± 10.09) mg/cm³; (111.02 ± 22.06) mg/cm³], and it had statistical difference (P=0.015; P=0.006). The depth of remineralized dentin in PSC group were (40.0 ± 16.9) μm and (54.5 ± 17.8) μm 2 and 4 weeks respectively, which were also statistically different from the control group (P =0.010;P=0.001). There were no statistical differences between the control group and MTA group. The above effects of FBG group were between PSC and MTA. CONCLUSION PSC has advantages in the speed, quality and depth of mineral deposition in the demineralized layer of artificial dentin caries. It would be expected to be an ideal material to promote the remineralization of dentin caries.
Dentin ; Silicon Dioxide/pharmacology* ; Dental Caries Susceptibility ; Minerals/pharmacology* ; Phosphorus/pharmacology* ; Tooth Remineralization/methods*

OBJECTIVETo investigate the effect of ozone on remineralization of enamel in vitro.

METHODSCaries-like lesions were prepared in the enamel of extracted cattle incisors with demineralizing solution. The specimens were treated with deionized water, 1000 mg/kg fluoride, 4.5 mg/L ozone, and pH-cycled. The scanning electron microscope (SEM) was used to observe the surface of enamel specimens. The effect of remineralization was assessed by three lesion parameters (fluorescent area, total and average fluorescence), which were measured with confocal laser scanning microscope (CLSM). The data were collected and analyzed by SNK test in ANOVA.

RESULTSSEM observation showed that the surface morphology of the deionized water group and ozone group were similar: porous and atactic; but the surface morphology of fluoride group was smooth and the aperture became smaller. The three parameters in the three groups were as follows, respectively. Delta A were (0.31 +/- 0.28), (1.73 +/- 0.63) and (0.28 +/- 0.19) x 10(4) microm2, Delta TF were (0.42 +/- 0.34), (2.53 +/- 0.73) and (0.48 +/- 0.27) x 10(5), Delta AF were (3.35 +/- 2.55), (46.51 +/- 16.64) and (4.95 +/- 3.05). The fluoride group was significantly greater than deionized water group and ozone group (P < 0.05); but there was no significant difference between the deionized water group and ozone group.

CONCLUSIONSThe results of this in vitro study suggest that ozone has no effect on remineralization of enamel blocks.

Animals ; Cattle ; Dental Enamel ; drug effects ; pathology ; ultrastructure ; In Vitro Techniques ; Microscopy, Electron, Scanning ; Ozone ; pharmacology ; Tooth Demineralization ; pathology ; Tooth Remineralization

OBJECTIVETo investigate the transformation of microhardness and microstructures of human dental fluorosis after demineralization and remineralization in vitro.

METHODSForty human dental fluorosis enamel blocks were demineralized by acid-etching gel, then subjected to 1.0% casein phosphopeptides stabilized calcium phosphate (CPP-CP) for remineralization. Surface enamel microhardness was measured on the enamel blocks before and after demineralization and after remineralization. The enamel specimens was observed by stereomicroscope and scanning electron microscope, then sectioned (100 microm) and examined by transmission light microscope and polarized light microscope.

RESULTSBefore demineralization, the average knoop hardness value of the fluorosed teeth was (241.53 +/- 21.31) kHV. After demineralization, obvious decrease of the surface hardness of the enamel was observed, the mean value was (175.76 +/- 24.99) kHV (P < 0.05), the percent of the surface microhardness demineralization (% SMHD) was (27.23 +/- 1 4.79)%, and major demineralization was under the surface of the enamel, which was similar to the early natural enamel caries. After remineralization, obvious increase of the surface hardness of the enamel was observed, the mean value was (210.17 +/- 21.48) kHV (P < 0.05), the percent of the surface microhardness remineralization (% SMHR) was (52.32 +/- 4.23)%, major remineralization was under the surface of the enamel.

CONCLUSIONRemineralization could be used to prevent and cure the early natural enamel caries of fluorosed dental teeth.

Calcium Phosphates ; Cariostatic Agents ; Caseins ; Dental Caries ; Dental Enamel ; Hardness ; Humans ; In Vitro Techniques ; Tooth Demineralization ; Tooth Remineralization