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PubMed1993

Cytotoxicity and dentin permeability of carbamide peroxide and hydrogen peroxide vital bleaching materials, in vitro.

There has been recent concern about the inadvertent exposure of dentin with patent tubules as well as gingiva to bleaching systems containing 10-15% carbamide peroxide or 2-10% hydrogen peroxide for more than a few minutes. The aims of the present study were: (1) to determine the cytotoxicity of dilutions of hydrogen peroxide in cell culture; (2) to measure hydrogen peroxide diffusion from bleaching agents through dentin in vitro; and (3) to determine the risk of hydrogen peroxide-induced cytotoxicity from exposure of dentin to these vital bleaching agents. The 50% inhibitory dose (ID50) of hydrogen peroxide to succinyl dehydrogenase activity in cultured cells was found to be 0.58 mmol/L after 1 h. All bleaching materials demonstrated diffusion of hydrogen peroxide through dentin in an "in vitro pulp chamber" device. The one- and six-hour diffusates of all bleaching agents through 0.5-mm dentin exceeded the ID50 in monolayer cultures. Inhibition of succinyl dehydrogenase activity corresponded to the amount of hydrogen peroxide that can rapidly diffuse through dentin in vitro and reach concentrations which are toxic to cultured cells in less than 1 h.

3T3 Cells↗
PubMed1995

Dentinal diffusion of hydroxyl ions of various calcium hydroxide pastes.

The aim of this study was to analyze in vitro the dentinal diffusion of hydroxyl ions of calcium hydroxide pastes, prepared with different acid-base vehicles, in an inert nitrogen atmosphere. Sixty maxillary incisors with mature apexes were selected and after access and root canal preparation each root was filled with calcium hydroxide pastes prepared with different vehicles: saline solution, anesthetic and polyethylene glycol 400. The roots were then sectioned 2 mm from the apical vertex and the teeth mounted in the center of a round platform, filled with saline solution up to 2 mm from the root tip. The platforms remained inert in an atmosphere of nitrogen, completely sealed, in the absence of light and with a constant temperature of 36.5 degrees C. Diffusion analysis of the hydroxyl ions was carried out by a colorimetric method on days 7, 15, 30, 45 and 60. Calcium hydroxide pastes prepared with saline solution and anesthetic showed a pH change of 5-7 to 7-8 after 30 days, remaining at this level at 60 days. In the polyethylene glycol 400 group, the same alteration occurred at 45 days, and continued at 60 days.

Calcium Hydroxide↗
PubMed1982

The effects of vinblastine on the cell structure and activity in the rat incisor enamel organ during the secretory stage in vivo as shown by radioautography using 3H-proline, 3H-serine and 3H-fucose.

Four hours after injection of vinblastine sulphate (VBL) the cells of the enamel organ of the rat incisor showed: 1) loss of polarity in the tall secretory ameloblasts--secretory granules, which were lacking in the Tomes processes accumulated in the supranuclear area; condensing vacuoles also accumulated near dictyosomes; enlarged intercellular spaces without disruption of intercellular junctions; lysosomal structures and autophagic vacuoles. 2) an increase of lysosome-like structures in the outer enamel epithelium, the stellate reticulum and the stratum intermedium. 3) a severe reduction in number of free ribosomes in the stratum intermedium as well as an increase in size of the Golgi complex: numerous electron lucent vesicles appeared. These findings as well as radioautographic data demonstrated 1) the impairment of secretory activity of ameloblasts. 2) the restriction of permeability in the enamel organ suggesting strong interaction between VBL and the membranes.

Ameloblasts↗
PubMed1997

Diffusion of resin monomers through human carious dentin in vitro.

The diffusion of 2-hydroxyethylmethacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) from light cured bonding resin-composite resin restorations through human carious dentin was investigated. Extracted human molar teeth with different degrees of caries were obtained from consenting donors. Teeth were classified into three groups according to caries severity (mild, moderate and severe) using subjective criteria. The outer carious lesions were then removed guided by a proprietary caries detector dye. Teeth with exposure of the pulp space after caries removal were excluded from the study. A polypropylene chamber was attached to the cemento-enamel junction of each tooth to contain 1 ml distilled water. Each cavity was restored with a HEMA containing bonding resin then a TEGDMA-containing resin composite. Water samples were retrieved over a time course and analyzed by high performance liquid chromatography. There was great variation between teeth in HEMA and TEGDMA permeability. The cumulative amounts released were of similar magnitude to those observed in non-carious teeth for the mild and moderately-severe groups. However, the cumulative amounts released were markedly greater in severely carious teeth than in those with moderate or mild caries.

Adult↗
PubMed2005

Effect of bleaching agents on bonding to pulp chamber dentine.

AIM: To determine the effect of intracoronal bleaching agents on adhesion of bonding agents to pulp chamber dentine. METHODOLOGY: Forty extracted human maxillary anterior teeth were randomly divided into four groups of 10 teeth each. Bleaching agents were sealed in pulp chambers for 7 days, as in clinical use. Group 1 (control): distilled water, group 2: 35% hydrogen peroxide, group 3: sodium perborate mixed with water, and group 4: sodium perborate mixed with 35% hydrogen peroxide. Teeth were stored in saline at 37 degrees C for 7 days. After the bleaching agent was removed, teeth were leached in water for a further 7 days prior to bonding. The crown was cut vertically from mesial to distal and the labial pulp chamber dentine was prepared for bonding with Clearfil SE-Bond and filled with resin composite (Clearfil AP-X). The bonded specimens were kept moist at 37 degrees C for 24 h. Microtensile bond strengths were determined using a universal testing machine. Additional teeth were prepared using the same bleaching procedures to investigate the scanning electron microscopic appearance of the dentine surface. RESULTS: Mean values (+/-SD) of microtensile bond strength for the experimental groups were: group 1: 5.29 +/- 2.21 MPa, group 2: 5.99 +/- 1.51 MPa, group 3: 9.17 +/- 1.65 MPa and group 4: 3.99 +/- 1.31 MPa. Dentine treated with sodium perborate in water (group 3) had significantly higher mean bond strength when compared with the other three groups (P < 0.05, Tukey's test). Mean bond strength was lowest when dentine was treated with sodium perborate plus hydrogen peroxide (group 4). CONCLUSIONS: In terms of subsequent bond strength during restoration, sodium perborate mixed with distilled water appears to be the best intracoronal bleaching agent.

Borates↗
PubMed2004

In vitro assessment of dentinal permeability after the use of ultrasonic-activated irrigants in the pulp chamber before internal dental bleaching.

This in vitro study aimed to assess dentin permeability quantitatively after the use of different irrigants into the pulp chamber, with or without ultrasonic activation, before the application of an internal bleaching agent. Thirty maxillary anterior teeth, treated endodontically, were randomly assigned to six groups, according to the irrigant used: group I, distilled water; group II, 17% EDTA; group III, 1% sodium hypochlorite; for groups IV, V, and VI, respectively, the same solutions were used, but were ultrasonicated. In groups I, II, and III, the irrigant that filled the pulp chamber was left undisturbed for 15 s and was then aspirated; in groups IV, V, and IV, the irrigants were placed into the pulp chamber, ultrasonic-activated for 15 s, and were then aspirated. This sequence was repeated three times for all groups. Afterwards, for all groups, the pulp chamber was dried, filled with a bleaching agent, and sealed with glass ionomer cement. At each change of the whitening agent, these procedures were repeated. Then, the temporary restorations were removed, access cavities were cleaned, and teeth were immersed in a 10% copper sulfate aqueous solution, submitted to vacuum and immersed in a 1% rubianic acid alcohol solution. Copper ion penetration was revealed by the rubianic acid. After staining, roots were removed at the cemento-enamel junction (CEJ) and sectioned in a mesiodistal direction starting from the cervical plug level. The sections were thinned, observed under an optical microscope, the images were digitized, and copper ion penetration was measured in each section using a specific software. Means and SD were: group I, 2.41 (+/-1.45); group II, 5.22 (+/-1.79); group III, 8.32 (+/-2.55); group IV, 3.73 (+/-0.89); group V, 14.83 (+/-4.99); and group VI, 10.51 (+/-2.65). Statistical analysis using two-way anova and Tukey test showed that, regardless of the irrigant, ultrasonication increased dentinal permeability (P < 0.01). Comparing the overall effectiveness of the tested solutions, EDTA yielded the greatest increase in dentinal permeability (P < 0.01). Based on these results, it may be concluded that use of ultrasonic-activated irrigants in the pulp chamber, before the accomplishment of internal dental bleaching procedures, may result in a remarkable increase of dentin permeability, which may enhance the efficiency of the whitening agent.

Chelating Agents↗
PubMed2026

P2X7 Receptor in Rare Diseases: Shared Molecular Mechanisms and Therapeutic Implications.

Rare diseases (RDs) are individually uncommon but collectively affect a large global population, and the vast majority still lack effective disease-modifying therapies. With advances in genomics and data-sharing platforms, research has increasingly shifted from a single-disease perspective to the search for convergent molecular pathways that might be shared across clinically distinct entities. In this context, the purinergic P2X7 receptor (P2X7R) has emerged as a putative "shared molecular platform" due to its central role in inflammation amplification, cell death and immune regulation. P2X7R is an ATP-gated ion channel with unique structural and functional features: under high extracellular ATP, it not only forms a non-selective cation channel but can also dilate into a "large pore" permeable to macromolecules, thereby triggering Ca2+overload, NLRP3 inflammasome assembly, reactive oxygen species (ROS) production and apoptotic/necrotic-like cell death. This review briefly outlines the epidemiology of RDs and the structural-functional characteristics of P2X7R, then systematically summarizes current evidence linking P2X7R to multiple rare diseases, including Charcot-Marie-Tooth disease, Guillain-Barr&#xe9; syndrome, amyotrophic lateral sclerosis, Huntington's disease, multiple sclerosis, and selected inflammatory and metabolic RDs (CAPS, familial Mediterranean fever, Systemic sclerosis, Dravet syndrome and Gaucher disease). By comparing P2X7R expression and functional alterations, downstream signaling pathways and pharmacological data from animal models across these conditions, we propose that a P2X7R-dependent network centered on a "Ca2+-NLRP3-inflammation/cell death axis" may constitute a common pathogenic backbone for diverse RDs. At the same time, disease-specific spatiotemporal expression patterns of P2X7R in central vs peripheral nervous systems and in immune vs target organ cells confer marked context dependence and "double-edged sword" properties. Finally, we discuss opportunities and challenges for P2X7R-targeted strategies, including the impact of disease stage and sex differences on therapeutic efficacy, and key bottlenecks in translating preclinical findings into clinical benefit. A deeper understanding of both shared and disease-specific roles of P2X7R may provide a conceptual framework and therapeutic entry point for precision stratification and multi-target interventions in rare diseases.

P2X7 receptor↗
PubMed2004

Effect of sodium hypochlorite treatment on the molecular composition and morphology of human coronal dentin.

PURPOSE: The aim of the present study was to evaluate the deproteination potential of 5% aqueous NaOCl solution applied by rubbing action on the molecular composition and morphology of smear-layer covered and acid-etched human coronal dentin surfaces. MATERIALS AND METHODS: Paired specimens (n = 4 x 2 per group) of acid-etched (Group A) and smear-layer covered (Group B) human coronal dentin surfaces were sequentially treated with the NaOCl solution for time intervals ranging from 5 s to 120 s and analyzed by reflectance FTIR microspectroscopy and tapping mode atomic force microscopy. The changes in the mineral (v4 P-O stretching vibrations) to matrix (C = O stretching vibrations of amide I) peak area ratios and in the Ra roughness parameter were used to quantify the effect of treatment. Two-way ANOVA and Dunn's tests were used to assess the differences within each group and between groups (a = 0.05). RESULTS: In both groups, NaOCl treatment reduced organic matrix (amide I, II, III peaks), but did not affect carbonates and phosphates. In group A, the rate of deproteination was slow, and reached a peak value after 120 s. Tubule orifices became visible after 40 s of treatment; after 120 s, excessive porosity was detected, with Ra values presenting no statistically significant difference from group B. In group B after 10 s, the extent of deproteination was enhanced, reaching a plateau between 30 s and 60 s, and attaining a maximum after 120 s. Tubule diameter, intertubular porosity, and Ra were increased; intertubular dentin area was reduced. For both groups after 40 s of treatment, the mineral to matrix ratio recorded was similar to smear-layer-free sectioned dentin. CONCLUSION: The results of the present study imply that deproteination of mineralized or acid-etched dentin surfaces within a clinically relevant time frame may provide methods for bonding to dentin alternative to conventional technique-sensitive dentin hybridization.

Acid Etching, Dental↗
PubMed2005

Self-etching adhesives: review of adhesion to tooth structure part II.

UNLABELLED: Self-etching adhesives are steadily increasing in popularity among dental practitioners with their easy handling technique and their promise of no post-op sensitivity. As with any new bonding material, in vitro and in vivo investigations are required to assess the clinical efficacy of these systems. OBJECTIVES: The current literature was reviewed to provide information on these systems, including the influence of their acidity and permeability on the quality of the bond, the role of water in long-term degradation of the bond in in vivo and in vitro studies, and the clinical efficacy of the self-etching adhesives in clinical research studies. DATA SOURCES: Published abstracts, reviews, laboratory reports and clinical research papers in the dental literature. CONCLUSIONS: Very little information is available on self-etching systems pertaining to the long-term in vitro and in vivo durability of their bond and their medium- to long-term clinical outcome. Although post-op sensitivity seems to be something of the past, short-term clinical studies show that some self-etching adhesives do not perform as well as total-etch systems.

Acid Etching, Dental↗
PubMedDate not supplied

Dentinal adhesive with composite restorations: a clinical and microstructural evaluation.

It is generally accepted that the application of dentin-enamel adhesive should involve not only the etched enamel but also the dentinal surface. For this purpose, new bonding agents requiring dentin etching and the combined use of bifunctional groups (Primers) as well as hydrophilic resins have been introduced. This study used scanning electron microscopy to analyze the relationship between dentin and fluid resin of three bonding agents. The results demonstrated that the adhesive monomers easily penetrated the etched dentin, sealing the dentinal tubules and creating a resin dentin interdiffusion zone (hybrid layer). As a result, the microleakage between dentin and resin composite restorations, responsible for postoperative tooth sensitivity, pulpal inflammatory reaction, and secondary decay, is greatly reduced.

Acid Etching, Dental↗
PubMed1989

[Histopathological study of experimental periodontitis in rats--ultrastructures, permeability, immunohistochemistry, and morphometric analysis in both pocket and long junctional epithelial].

UNLABELLED: To elucidate the biological characteristics of both pocket and long junctional epithelia in experimental periodontitis, elastic rubber was inserted between the first and second molars of the left maxilla in rats. The rubber was removed after a week. An immunohistochemical study using anti-laminin and permeability experiments using peroxidase were conducted; examinations were made of ultrastructures and lanthanum; and a morphometric analysis was made of the distribution of capillaries immediately below the epithelium. RESULTS: 1. Periodontal pockets formed from 5 days to 2 weeks after removal of the rubber. The long junctional epithelium was appearent from the fourth week after removal. Immunohistochemical study showed that laminin was located at the internal and external basal laminae in the long junctional epithelium but not on the surface of the pocket epithelium. 2. Electron microscopy showed the pocket epithelium to consist of flattened cells aligned parallel to the tooth surface in the coronal portion. The epithelium, which included numerous vacuoles, manifested especially wide intercellular spaces in which a large number of polymorphonuclear leukocytes were evident. Bacteria surrounded by neutrophils could be seen on the surface of the cementum in the pocket. Invading neutrophils split the epithelium at the central portion of the pocket. In the apical portion, the epithelium formed spindles that adhered to the cementum by means of half-desmosomes. Many neutrophils and fenestrated capillaries were observed in connective tissue immediately below the epithelium. 3. The long junctional epithelium consisted of 2 or 3 cell layers aligned parallel to the tooth surface. Intercellular spaces in the long junctional epithelium were as wide as those in the pocket epithelium and contained a small number of lymphocytes and a few neutrophils. Half-desmosomes were detected between the epithelial cells and the cementum. From the central to the apical region, epithelial tissues assumed a knife-edge form. Desmosomes and gap junctions occurred among these cells. Dense granules containing a limiting membrane and homogeneous electron-dense material were observed int he peripheral cytoplasm. Although fibroblasts aligned parallel to the epithelium occurred in them, few collagen fibers, inflammatory cells and capillaries were to be recognized in the connective tissue. 4. Permeability experiments in the pocket and the long junctional epithelium produced analogous results. Light microscopy showed that, in both epithelia, peroxidase penetrated into intercellular spaces and leaked into the pocket. Electron microscopy showed that, as an electron-dense material, lanthanum was detected in intercellular spaces and connective tissues.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Biologically active extracellular products of oral viridans streptococci and the aetiology of Kawasaki disease.

A bacteriological study of isolates from the oral cavity of patients with Kawasaki disease (KD), age-matched non-KD patients and healthy children, showed that over half the KD and control isolates had gram-positive, catalase-negative cocci. About 50% of these organisms were identified as viridans streptococci by means of an API Strep 20 kit. Further identification by fluorometric DNA-DNA hybridisation demonstrated that the predominant species were S. oralis and S. mitis, each of which accounted for 25% of the isolates of viridans streptococci; 40% of viridans strains were unidentifiable; and S. sanguis and S. parasanguis were minor components. Studies in vivo showed that insertion of culture supernates of most of the viridans streptococci increased capillary permeability and induced redness with swelling and occasional bleeding in rabbit skin. One-third of S. mitis strains and one-fifth of the unidentified strains caused aggregation of human blood platelets, whereas S. oralis and other strains had no such effect. The distribution of extracellular lipoteichoic acids and glucan produced in the presence of sucrose was also examined. There were no significant differences in the recovery rate of viridans streptococci forming these biologically active extracellular products between KD and control groups.

Adult↗
PubMed2004

The effects of water and acetone-based dentin adhesives on apical microleakage.

In this study, the aim was to assess the in vitro apical microleakage of a resin-based sealer used with two different adhesives. Thirty nine freshly extracted maxillary incisors were used. The teeth were decoronated at the cemento-enamel junction with a water-cooled fissure bur. Chemo-mechanical debridement of the root canals was accomplished with the step-back technique. The smear layer was removed by 19% ethylenediamine tetra acetic acid (EDTA). The roots were then divided into three experimental groups of thirteen teeth in each. Specimens in group 1 were filled with gutta-percha, AH Plus sealer, and water-based adhesive system (Syntac Single Component). Group 2 specimens were filled with gutta-percha, AH Plus sealer, and acetone-based dentin adhesive (Prime & Bond NT ). Specimens of group 3 were filled with only gutta-percha and AH Plus sealer (no adhesive was applied). The teeth were immersed into 2% methylene blue solution. Apical sealing qualities were assessed by measuring the linear dye penetration with a stereomicroscope. Dentin tubule penetration was observed under scanning electron microscopy (SEM). Results showed no statistically significant difference between the materials used, however, the leakage in group 2 was less than group 1 and 3.

Acetone↗
PubMed2005

[The penetration of various adhesives into early enamel lesions in vitro].

The aim of the present study was to evaluate the penetration depth (PD) and the thickness of the oxygen inhibition layer (OIL) of a fissure sealant (Helioseal, Vivadent) and various adhesives (Heliobond, Excite, Vivadent; Resulcin, Merz; Solobond M, Voco; Prompt L-Pop, 3M-Espe) applied to enamel lesions in vitro. From 27 bovine teeth 54 enamel specimens were prepared and covered with nail varnish (control) thus obtaining three windows for treatment. After demineralisation (pH 5.0, 14 d) two of the windows were etched with phosphoric acid (20%, 5 s), whereas the third area served as control. The specimens were divided randomly into six groups (n = 9) and the respective adhesive was applied (90 s), either once or twice. Light-curing followed each application. Enamel slabs (perpendicular to the surface) were cut and studied after infiltration with a fluorescent low-viscous resin using confocal microscopy (CLSM). The image of the lesion was divided into two areas with different grey values. Lesion depths were calculated (ImageJ) from the surface to that point in the lesion where the grey value clearly changed to a darker grey value. The zone with the darker grey values marked the front of demineralisation. Mean lesion depths (+/- SD) after demineralisation were measured at 105 (+/- 21) microm. After single application, Resulcin [89 (+/- 22)%] and Helioseal [98 (+/- 6)%] had almost completely penetrated the lesion. Heliobond [126 (+/- 33)%] and Excite [184 (+/- 40)%] penetrated even deeper than the defined lesion. For Excite double application decreased the OIL significantly (p = 0.03; adjusted paired t-test). Adhesives are capable to penetrate artificial initial enamel lesions completely. Follow-up studies are needed to confirm this effect for natural lesions.

Acrylates↗
PubMed2000

In vitro studies and modeling of a controlled-release device for root canal therapy.

Endodontic disease is caused primarily by bacteria that interact with periradicular host tissues. Therefore, treatment of endodontic disease aims at the exclusion of bacteria from the root canal system. This work focused on in vitro studies and modeling of a controlled-release device for delivering antimicrobial agents in root canals. A cylindrical, needle-shaped device was prepared consisting of a matrix core and a polymer coating, loaded with 30-45% chlorhexidine (CHX). The composition of the core, a blend of water-permeable polymers, and the thickness of the coating were tailored to impart various release rates. A relatively steady release rate for over 40 days after an initial burst was achieved using a formulation for long-term release, which is desirable for establishing and maintaining the necessary therapeutic levels. Mathematical models were developed for both in vitro and in vivo drug release into a liquid of limited volume, taking into account a moving boundary of the dispersed drug and a time-dependent boundary condition. A concentration-dependent effective diffusion coefficient was used to count increased porosity as the solid drug had dissolved. The finite element method and computer programs were applied to solve the differential equations and predict the in vitro and in vivo release kinetics. The model prediction agreed well with the in vitro experimental data and provided guidance for designing the device for in vivo release in root canals. The result of in vitro antimicrobial tests, performed using a bovine tooth model, suggested that the device was effective in reducing growth of microbes.

Algorithms↗
PubMed1993

The structure of dentin surfaces exposed for bond strength measurements.

The structure of dentin on three different levels, near enamel, central, and deep dentin, was examined. The solid area available for bonding was studied in a scanning electron microscope (JSM 840) connected to a computer-assisted image analysis instrument (IBAS 2). The number of tubule openings per unit area (frequency) and the area percentages of these tubule openings were recorded. Three dentin disks were obtained from both buccally and occlusally located dentin of a single tooth (third molars were used), and the two deeper levels were each 1.25 mm deeper than the level above. The disks showed an increasing number of tubules with an increasing diameter the deeper into the dentin they were cut. Disks from the occlusal part of the tooth showed, in general, a higher number and area percentage of tubule openings than the corresponding disks from the buccal part. The variation across each disk was also larger for disks from the occlusal part than from the buccal part of the tooth. This variation increased with increasing depth of dentin. The most solid dentin with the lowest variation was found in superficial disks of buccally located dentin.

Dental Bonding↗
PubMed1997

Changes in the permselectivity of human teeth during caries attack.

Previous studies have shown that enamel permselectivity can influence fluid composition within caries lesions during de- and remineralization. The permselectivity of human enamel, cementum, and dentin sections was examined, in a microwell model, by measurement of the membrane potential developed by KCl diffusion while the sections were immersed in solutions simulating resting (pH = 5.6) and cariogenic plaque fluid (pH = 4.8). In a second experiment, the effects of charged compounds (phytate and Zonyl-FSC) on the tooth permselectivity were examined. The average membrane potentials (+/- SD) in "resting plaque" solution were: sound enamel, 18.9 +/- 3.2 mV, n = 66; dentin, 0.9 +/- 9.2 mV, n = 59; and cementum, -0.8 +/- 8.2 mV, n = 42, with a positive sing indicating cation selectivity. The average membrane potentials became more negative in "cariogenic plaque" solution for all types of sections: sound enamel, 5.2 +/- 2.1 mV, n = 46; dentin, -8.1 +/- 7.4 mV, n = 45; and cementum, -14.3 +/- 8.0 mV, n = 34. In lesion enamel sections, the membrane potential was reduced from the non-lesion wells in both types of test solutions, while phytate treatment caused an increase of approximately 10 mV in potential (increased cation selectivity) in every enamel well in either "resting" or "cariogenic" solution. Treatment of enamel sections with Zonyl-FSC caused the membrane potential to become more negative in both test solutions, with many of the wells showing anion selectivity in the cariogenic "plaque-like" solution. However, the changes in enamel membrane potentials induced by Zonyl-FSC slowly increased toward the initial values after treatment, while the effects of the phytate pre-treatment persisted. Most dentin sections treated with phytate also showed an increase in potential after phytate treatment; however, Zonyl-FSC seemed to have little effect on the membrane potential of dentin. The results of this study suggest that modification of tooth permselectivity by surface-active agents may be a viable method of decreasing the rate of caries progression.

Dental Caries↗