Caries Model Research Articles

Molecular approaches for viable bacterial population and transcriptional analyses in a rodent model of dental caries.

Culturing methods are the primary approach for microbiological analysis of plaque biofilms in rodent models of dental caries. In this study, we developed strategies for the isolation of DNA and RNA from plaque biofilms formed in vivo to analyse the viable bacterial population and gene expression. Plaque biofilm samples from rats were treated with propidium monoazide to isolate DNA from viable cells, and the purified DNA was used to quantify total bacteria and the Streptococcus mutans population via quantitative polymerase chain reaction (qPCR) and specific primers; the same samples were also analysed by counting colony-forming units (CFU). In parallel, RNA was isolated from plaque-biofilm samples (from the same animals) and used for transcriptional analyses via reverse transcription-qPCR. The viable populations of both S. mutans and total bacteria assessed by qPCR were positively correlated with the CFU data (P < 0.001; r > 0.8). However, the qPCR data showed higher bacterial cell counts, particularly for total bacteria (vs. CFU). Moreover, S. mutans proportion in the plaque biofilm determined by qPCR analysis showed strong correlation with incidence of smooth-surface caries (P = 0.0022, r = 0.71). The purified RNAs presented high RNA integrity numbers (> 7), which allowed measurement of the expression of genes that are critical for S. mutans virulence (e.g. gtfB and gtfC). Our data show that the viable microbial population and the gene expression can be analysed simultaneously, providing a global assessment of the infectious aspect of dental caries. Our approach could enhance the value of the current rodent model in further understanding the pathophysiology of this disease and facilitating the exploration of novel anti-caries therapies.

Carbon dioxide laser and bonding materials reduce enamel demineralization around orthodontic brackets

Altering the structure of the enamel surface around the orthodontic bracket by reducing its content of carbonate and phosphate resulting from application of CO(2) laser may represent a more effective strategy in preventing caries in this region. This study aimed at determining whether irradiation with a CO(2) laser combined with fluoride-releasing bonding material could reduce enamel demineralization around orthodontic brackets subjected to cariogenic challenge. Ninety bovine enamel slabs were divided into five groups (n = 18): non-inoculated brain-heart infusion broth group, non-fluoride-releasing composite resin (NFRCR--control group), resin-modified glass ionomer cement (RMGIC), CO(2) laser + Transbond (L+NFRCR) and CO(2) laser + Fuji (L+RMGIC). Slabs were submitted to a 5-day microbiological caries model. The Streptococcus mutans biofilm formed on the slabs was biochemically and microbiologically analysed, and the enamel Knoop hardness number (KHN) around the brackets was determined. The data were analysed by ANOVA and Tukey tests (α = 0.05). Biochemical and microbiological analyses of the biofilm revealed no statistically significant differences among the groups. Lased groups presented the highest KHN means, which statistically differed from NFRCR; however, no difference was found between these lased groups. RMGIC did not differ from NFRCR which presented the lowest KHN mean. The CO(2) laser (λ = 10.6 μm; 10.0 J/cm(2) per pulse) use with or without F-bonding materials was effective in inhibiting demineralization around orthodontic brackets. However, no additional effect was found when the enamel was treated with the combination of CO(2) laser and an F-releasing material.

Streptococcus mutans Out-competes Streptococcus gordonii in vivo

Streptococcus gordonii and Streptococcus mutans avidly colonize teeth. S. gordonii glucosyltransferase (GtfG) and amylase-binding proteins (AbpA/AbpB), and S. mutans glucosyltransferase (GtfB), affect their respective oral colonization abilities. We investigated their interrelationships and caries association in a rat model of human caries, examining the sequence of colonization and non- vs. high-sucrose diets, the latter being associated with aggressive decay in humans and rats. Virulence-characterized wild-types of both species and well-defined mutants of S. gordonii with interrupted abpA and gtfG genes were studied. While both S. gordonii and S. mutans were abundant colonizers of rat’s teeth in the presence of either diet, if inoculated singly, S. mutans always out-competed S. gordonii on the teeth, independent of diet, strain of S. mutans, simultaneous or sequential inoculation, or presence/absence of mutations of S. gordonii’s abpA and gtfG genes known to negatively or positively affect its colonization and to interact in vitro with S. mutans GtfB. S. mutans out-competed S. gordonii in in vivo plaque biofilm. Caries induction reflected S. mutans or S. gordonii colonization abundance: the former highly cariogenic, the latter not. S. gordonii does not appear to be a good candidate for replacement therapy. These results are consistent with human data.

Potentials of Mouthwashes in Disinfecting Cariogenic Bacteria and Biofilms Leading to Inhibition of Caries

Objectives:The aim of this study was to compare the effects of certain commercially available mouthwashes on cariogenic bacteria and biofilms, following the acquisition of inhibition potentials of caries.Materials and Methods:Mouthwashes containing I) chlorhexidine gluconate (CHG; 0.0005% w/v), II) benzethonium chloride (BTC; 0.01% w/v), III) an essential oil (Listerine), and IV) povidone-iodine (PVP-I; 0.035% w/v) were tested on planktonic cariogenic bacteria, biofilms, and an ex vivo caries model. Bacterial aliquots were inoculated with each solution separately and vortexed for 10 seconds at room temperature. Bacterial viability was subsequently investigated by fluorescence microscopy (FM) after staining with a BacLight viability kit and the number of colony-forming units (CFUs) was counted. Similarly, mouthwash solutions were applied to artificial cariogenic biofilms, and bacterial viability of the biofilms was investigated as stated above. Inhibition potentials of two selected mouthwashes of carious lesions were investigated using biofilm-induced caries and a secondary caries model. In all steps, a phosphate-buffered saline (PBS) solution was included as a control.Results:Planktonic cariogenic bacteria and bacteria embedded in biofilms were killed in remarkably large numbers with Listerine and PVP-I treatment compared to PBS and other gargles. CFU counts also showed significant reduction after treatment with Listerine and PVP-I compared to other solutions (P<0.05). Listerine also displayed significant (P<0.05) inhibition effects in preventing the progression of demineralization.Conclusion:Bactericidal potencies of the mouthwashes varied significantly, suggesting that mouthwashes like Listerine can be useful for the prevention of caries and secondary caries.

Antimicrobial Photodynamic Therapy as a Strategy to Arrest Enamel Demineralization: A Short‐Term Study on Incipient Caries in a Rat Model†

In this study we developed a rat model of incipient caries to investigate the short-term effects of antimicrobial photodynamic therapy (aPDT) on oral microbiota regulation and demineralization arrestment. Twenty-nine male rats were submitted to caries induction. Early carious lesion was confirmed by optical coherence tomography (OCT) 5 days after experiment beginning in five animals. The remaining animals (n = 24) were randomly divided into two groups: control (n = 12), animals were untreated; and aPDT (n = 12), animals were treated with 100 μM of methylene blue for 5 min and irradiated by a light emitting diode at λ = 645 ± 30 nm, fluence rate of 480 mW cm(-2) and exposure time of 3 min. Bacterial burden was evaluated before, immediately after, 3, 7 and 10 days following treatment, and total number of microaerophilic bacteria was counted. OCT was also used to quantify teeth demineralization. A significant bacterial decrease of about 1.6 log was observed immediately after aPDT. Besides, bacterial load in aPDT group remained lower than control until 10 days post-treatment (P < 0.05) and variation of optical attenuation coefficient before and after aPDT was 15%, corroborating to caries arrestment. Put together, these findings suggest that aPDT was competent to reduce cariogenic bacteria and to avoid further mineral loss.

Effect of Gap Geometry on Secondary Caries Wall Lesion Development

Objective: To investigate how the size of the space between restoration and dentinal wall of the tooth affects the development of secondary caries lesions, especially wall lesions. Methods: Tooth-resin composite specimens were mounted on custom-made gap model stages and divided into 4 groups (n = 10): group 1 with a 30-µm gap throughout both enamel and dentin, group 2 with a 30-µm enamel gap and 530-µm dentinal gap, group 3 with 525-µm gaps in both enamel and dentin, and group 4 with 525-µm and 1,025-µm gaps in enamel and dentin, respectively. Specimens were gas sterilized and incubated in a cycling microbial caries model for 8 days and analyzed with confocal microscopy for lesion size at the enamel outer lesion (EOL), enamel wall lesion (EWL), dentin wall lesion A (DWL-A) next to the dentin-enamel junction (DEJ) and dentin wall lesion B (DWL-B) at 750 µm from the DEJ. Results: No difference in EOL or EWL size was found between the groups. DWL-A and DWL-B were larger in group 3 than groups 1 and 2. A larger DWL-B was found in group 3 than group 4. Conclusions: The presence of additional space at the dentinal wall area did not affect secondary caries development as long as the enamel gap was small. However, with enamel gaps of approximately 500 µm, the presence of the additional gap space at the dentinal wall led to the development of smaller dentinal wall lesions at the deeper parts of the simulated cavity. In uniform gaps, the size of the interface was positively correlated with the size of the dentinal wall lesions.

An artificial biofilm induced secondary caries model for in vitro studies

The aim of this study was to establish a new in vitro model for biofilm induced secondary caries studies using an oral biofilm reactor. An approximately 2 × 3 × 2 mm(3) sized dentino-enamel Class I cavity was prepared in the middle of a square-shaped specimen from the mid-labial portion of bovine incisors. The cavities were partially filled with either Clearfil AP-X with SE-Bond or Clearfil AP-X without any bond. Artificial biofilms were then formed on the resin composite filled surfaces using three species of oral bacteria in an oral biofilm reactor for 20 hours followed by 7- or 30-day incubation periods. The lesions were clearly visible on fluorescence microscopy and by scanning electron microscopy in the enamel at the interface of resin restorations in all samples. The data from image analysis showed that the lesion size was largest in the No-bond samples with statistically significant differences (p < 0.05). Demineralization along the cavity wall extended deeper in No-bond compared to SE-Bond samples and penetration was significantly deeper in No-bond 30-day samples. A primary artificial secondary caries model was established using biofilms for in vitro studies and the significance of using a bonding system could also be verified.

The Effects of Fractions from Shiitake Mushroom on Composition and Cariogenicity of Dental Plaque Microcosms in an In Vitro Caries Model

The aim of the current study was to investigate the anticariogenic potential of the (sub)fractions obtained from the edible mushroom shiitake (Lentinula edodes) in in vitro caries model. We used a modified constant depth film fermentor (CDFF) with pooled saliva as the inoculum and bovine dentin as a substratum. The test compounds were low molecular weight fraction (MLMW) of the shiitake extract and subfractions 4 and 5 (SF4 and SF5) of this fraction. Chlorhexidine (CHX) and water served as a positive and a negative control, respectively. Dentin mineral loss was quantified (TMR), microbial shifts within the microcosms were determined (qPCR), and the acidogenicity of the microcosms was assessed (CIA). From the compounds tested, the SF4 of shiitake showed strong inhibiting effect on dentin demineralization and induced microbial shifts that could be associated with oral health. The acid producing potential was increased, suggesting uncoupling of the glycolysis of the microbiota by the exposure to SF4. In conclusion, the results suggest that SF4 of shiitake has an anticariogenic potential.

Dentine caries inhibition through CO2 laser (10.6 μm) irradiation and fluoride application, in vitro

ObjectiveThe purpose of the study was to investigate whether dentine irradiation with a pulsed CO2 laser (10.6μm) emitting pulses of 10ms is capable of reducing dentine calcium and phosphorus losses in an artificial caries model. DesignThe 90 dentine slabs obtained from bovine teeth were randomly divided into six groups (n=15): negative control group (GC); positive control group, treated with fluoride 1.23% (GF); and laser groups irradiated with 8J/cm2 (L8); irradiated as in L8+fluoride 1.23% (L8F); irradiated with 11J/cm2 (L11); irradiated as in L11+fluoride 1.23% (L11F). After laser irradiation the samples were submitted to a pH-cycling model for 9 days. The calcium and phosphorous contents in the de- and remineralization solutions were measured by means of inductively coupled plasma optical emission spectrometer – ICP-OES. Additionally intrapulpal temperature measurements were performed. The obtained data were analysed by means of ANOVA and Tukey's test (α=0.05). ResultsIn the demineralization solutions the groups L11F and GF presented significantly lower means of calcium and phosphorous losses than the control group; and in L11F means were significantly lower than in the fluoride group. Both irradiation parameters tested caused intrapulpal temperature increase below 2°C. ConclusionIt can be concluded that under the conditions of this study, CO2 laser irradiation (10.6μm) with 11J/cm2 (540mJ and 10Hz) of fluoride treated dentine surfaces decreases the loss of calcium and phosphorous in the demineralization process and does not cause excessive temperature increase inside the pulp chamber.

Inhibition of Streptococcus mutans biofilm accumulation and development of dental caries in vivo by 7-epiclusianone and fluoride

7-Epiclusianone (7-epi), a novel naturally occurring compound isolated from Rheedia brasiliensis, effectively inhibits the synthesis of exopolymers and biofilm formation by Streptococcus mutans. In the present study, the ability of 7-epi, alone or in combination with fluoride (F), to disrupt biofilm development and pathogenicity of S. mutans in vivo was examined using a rodent model of dental caries. Treatment (twice-daily, 60s exposure) with 7-epi, alone or in combination with 125 ppm F, resulted in biofilms with less biomass and fewer insoluble glucans than did those treated with vehicle-control, and they also displayed significant cariostatic effects in vivo (p < 0.05). The combination 7-epi + 125 ppm F was as effective as 250 ppm F (positive-control) in reducing the development of both smooth- and sulcal-caries. No histopathological alterations were observed in the animals after the experimental period. The data show that 7-epiclusianone is a novel and effective antibiofilm/anticaries agent, which may enhance the cariostatic properties of fluoride.

A prediction model for root caries in an elderly population

To identify factors associated with root caries development in a 12- month period, in an elderly Mexican population, so as to develop a prediction model for the occurrence of root caries. A case-cohort study was carried out with 698 randomly selected beneficiaries of the Mexican Institute of Social Security (IMSS), residing in the southeast of Mexico City. Initially, base line (t₀) data regarding sociodemographic variables, general health, general and oral healthy habits, salivary conditions, cariogenic microorganisms and oral health clinical indicators were collected. Twelve months from the date of the first clinical evaluation (t₁), a new examination was carried out to determine the root caries increment. Variables that showed a significant association (P ≤ 0.05) with the root caries increment were included in the prediction model. Six hundred and ninety-eight elderly subjects were included in the cohort (t₀), with 76.1% (n = 531) of the elderly patients followed up at 12 months (t₁). Incidence of root caries was 21.7% (n = 115), a mean root caries increase of 0.4 (1.0) surfaces. The variables, DLBA limitations (Yes), smoking (Yes), mouthwash (No), Mutans streptococci (≥10⁵ CFU/ml), healthy root surfaces (≥6) and Root Caries Index (≥8%), showed a statistically significant association (P < 0.05). This model showed a correct classification in 80.0% (n = 425) and an area under the Receiver Operating Characteristic curve of 0.75. This is a good prediction model for the 12 months root caries increment in this population of elderly Mexicans.

Predictor Model of Root Caries in Older Adults: Reporting of Evidence to the Translational Evidence Mechanism

Compared to younger adults, older adults are at greater risk for root caries. A model of root caries may assist dentists in predicting disease outcomes. OBJECTIVES: Using the Iowa 65+ Oral Health Survey, analysis was done to model the patterns of the root caries development in older adults. Methods: The statistical analysis included Markov chain modeling, model estimation and validation. Results: The model effectively predicts root caries using an 18-month predictive cycle and is validated up to 36 months (two cycles), with no significant differences (Chi-square test p-values >0.1) between predicted and observed distributions. However, we do not have observed data for validation beyond 36 months since the model was designed to perform only at single or multiple 18-month cycles. As expected, the predicted distribution at 54-month (3 cycles) and the observed distribution at 60-month differed significantly (p<0.0001).Conclusions:The model demonstrated a high probability that a sound surface will remain caries free. However, one and multiple-surface lesions aggressively infect adjoining surfaces. Maturing of the carious lesion occurs with the 4-surface lesion, decreasing the probability of tooth loss. Thus, maintaining a sound root surface and early treatment intervention reduces the risk of tooth dysfunction (morphological destruction) and loss.DATABASE FILTERS: P: Tooth/Subject characteristics-Older adults, 65 years of age or more, male and female participants, regional rural Iowa residents, race unspecified, functional status-non-institutionalized level unspecified, risk level unspecified I: Root caries P (C-not applicable): Probability/Statistical significance for decision data only/Clinical significance-dataset over 20 years old/Utility data not included/Cost data not included/Meaning in practice undetermined. O: Each year through a three year cycle, caries progression from a sound root surface A: Data attached:■ Published manuscript□ Unpublished manuscript□ Raw dataR: Primary author contact information present

Predictor Model of Root Caries in Older Adults: Reporting of Evidence to the Translational Evidence Mechanism~!2009-09-09~!2009-10-14~!2010-07-16~!

Predictor Model of Root Caries in Older Adults: Reporting of Evidence to the Translational Evidence Mechanism~!2009-09-09~!2009-10-14~!2010-07-16~!

Nondestructive Assessment of Early Tooth Demineralization Using Cross-Polarization Optical Coherence Tomography.

New methods are needed for the nondestructive measurement of tooth demineralization and remineralization to monitor the progression of incipient caries lesions (tooth decay) for effective nonsurgical intervention and to evaluate the performance of anticaries treatments such as chemical treatments or laser irradiation. Studies have shown that optical coherence tomography (OCT) has great potential to fulfill this role since it can be used to measure the depth and severity of early lesions with an axial resolution exceeding 10 µm, it is easy to apply in vivo and it can be used to image the convoluted topography of tooth occlusal surfaces. In this paper, a review of the use of polarization-sensitive-OCT for the measurement of tooth demineralization is provided along with some recent results regarding improved methods for the detection of caries lesions in the earliest stages of development. Automated methods of analysis were used to measure the depth and severity of demineralized bovine enamel produced using simulated caries models that emulate demineralization in the mouth. Significant differences in the depth and integrated reflectivity from the lesions were detected after only a few hours of demineralization. These results demonstrate that cross-polarization-OCT is ideally suited for the nondestructive assessment of early demineralization.

Uitgangspunten van mondzorg voor kinderen

In this article the principles of child oral health care in the Netherlands and the consequences of cariological principals of oral health care delivery to children are described. First of all the age of the child plays a very significant role in decisions concerning prevention and restoration. In addition, the combination of a positive attitude on the part of the dentist and a pain-free treatment can prevent fear of treatment and avoidance behaviour of the children. In the treatment of carious lesions, moreover, the oral health care provider should consider to what extent the problem is related to behaviour and fits in the multi-factorial caries model. Restorative treatments should be considered as supporting prevention, reducing caries activity and eliminating the effects of neglected oral health care. Prevention has to be seen as an essential element of the treatment model and it should start early from the standpoint of habit formation and the rapid demineralization process in the deciduous dentition which results from failed preventive care.

Caries Inhibition by and Safety of Lactobacillus paracasei DSMZ16671

Lactobacillus paracasei DSMZ16671, even if heat-killed, sensitively co-aggregates mutans streptococci specifically. Mutans streptococci are strongly implicated in caries induction in humans and rodents. We hypothesized: (1) that S. mutans recoveries from rats’ teeth in vivo will decrease, with an associated decrease in caries, if these lactobacilli are fed to rats in an established caries model; and (2) that toxicological assays of these lactobacilli will show them to be benign. Four groups of specific-pathogen-free rats were formed: S. mutans 10449S-inoculated/16671-supplemented diet; un-inoculated/16671-supplemented diet; S. mutans 10449S-inoculated/placebo diet; and un-inoculated/placebo diet. Standard tests of toxicity and mutagenicity of heat-killed DSMZ16671 were performed. S. mutans recoveries were significantly reduced both in mid-experiment and at termination, as were caries lesion scores for the rats inoculated by S. mutans and fed the DSMZ16671 supplement, by comparison with controls. Neither toxicity nor mutagenicity of DSMZ16671 was detected. Use of heat-killed DSMZ16671 is efficacious in rats and appears safe.

Cariogenicity and Acidogenicity of Human Milk, Plain and Sweetened Bovine Milk: An In Vitro Study

The objective of the present study was to determine the acidogenicity and cariogenicity of human breast milk and plain and sweetened packaged bovine milk. First all milk specimens were inoculated with a cariogenic strain of Streptococcus mutans (SM). The culture pH and number of colony forming units (cfus) was assessed. Second, the buffer capacity of all milk specimens was evaluated by mixing with acid. Finally, enamel windows were created on extracted primary maxillary incisors and colonized with SM. Enamel demineralization and caries progression were assessed visually, histologically, and radiographically at the end of twelve weeks. Plain and sweetened packaged bovine milk (BM) supported greater bacterial growth and caused more fermentation than human breast milk (HBM). The buffer capacity values for plain and sweetened bovine milk were highest; HBM, however had poor buffering capacity. The progression of the carious lesions into the dentin was most severe for the sweetened bovine milk. HBM and plain bovine milk are relatively cariogenic in an in vitro caries model in the absence of saliva. However, supplementation with sugar exponentially enhances the cariogenic potential of the natural milk.

The Relationship Between Dental Caries and Unleaded Gasoline Usage Among Children

ISEE-0089 Background and Objective: The use of leaded gasoline can cause combustion particulates and lead emissions in air. Empirical studies found that higher lead level in air is associated with higher blood lead levels (BLLs) in human beings. In Taiwan, the use of unleaded gasoline has been completely adopted since 2000. The use of unleaded gasoline probably reduces lead emissions in air. Past literature indicates that lead emissions may increase the prevalence of dental caries. Therefore, this study investigates the relationship between dental caries and unleaded gasoline usage. Methods: Our data were collected from three official databases between 1998 and 2007:1) lead level in air was from Taiwan's Environmental Protection database; 2) the diagnoses of the dental disorders were from Taiwan's National Health Insurance database; 3) the Income Per Capita was from Taiwan's Ministry of Economic Affairs. Using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), we identified the diagnoses code with dental disorders from 520 to 529. Multiple linear regression was used to estimate the impact of dental caries on age, gender, income, lead levels in air and the number of dentists. Results: The levels of lead in air reduced steadily from 0.09 to 0.06μg/m3. In all beneficiaries, the average frequency of caries (ICD-9 code 521.0) also declined gradually from 2.38 to 2.1. However, the average frequency of dental disorders (ICD-9 code from 520 to 529) was not decreased (3.44 vs. 3.46 times). In addition, the frequency of decay was notably reduced in 5–14 years old and their caries model of linear regression revealed that caries were highly associated with the lead levels in air (β = 1.06; P = 0.01). Conclusion: The average frequency of caries was significantly related to the use of unleaded gasoline, especially in the 5–14 age-groups.

Good Manufacturing Practices production and analysis of a DNA vaccine against dental caries

To prepare a clinical-grade anti-caries DNA vaccine pGJA-P/VAX and explore its immune effect and protective efficacy against a cariogenic bacterial challenge. A large-scale industrial production process was developed under Good Manufacturing Practices (GMP) by combining and optimizing common unit operations such as alkaline lysis, precipitation, endotoxin removal and column chromatography. Quality controls of the purified bulk and final lyophilized vaccine were conducted according to authoritative guidelines. Mice and gnotobiotic rats were intranasally immunized with clinical-grade pGJA-P/VAX with chitosan. Antibody levels of serum IgG and salivary SIgA were assessed by an enzyme-linked immunosorbent assay (ELISA), and caries activity was evaluated by the Keyes method. pGJA-P/VAX and pVAX1 prepared by a laboratory-scale commercial kit were used as controls. The production process proved to be scalable and reproducible. Impurities including host protein, residual RNA, genomic DNA and endotoxin in the purified plasmid were all under the limits of set specifications. Intranasal vaccination with clinical-grade pGJA-P/VAX induced higher serum IgG and salivary SIgA in both mice and gnotobiotic rats. While in the experimental caries model, the enamel (E), dentinal slight (Ds), and dentinal moderate (Dm) caries lesions were reduced by 21.1%, 33.0%, and 40.9%, respectively. The production process under GMP was efficient in preparing clinical-grade pGJA-P/VAX with high purity and intended effectiveness, thus facilitating future clinical trials for the anti-caries DNA vaccine.

Distortional effect of beam-hardening artefacts on microCT: a simulation study based on an in vitro caries model

The aim of this study was to assess quantitatively the degrading effect of artefacts caused by beam hardening on the microscopic computerized tomography (microCT) measurements of an in vitro caries model. A simulation-based method was described, with which the degrading effect of microCT artefacts on certain parameters of the observed structure could be determined. Simulations were carried out with polychromatic and monochromatic X-ray source, and a linearization method with a second-order polynomial fit algorithm was used in specific cases to correct the beam hardening artefact. The virtual test object was a half-crown of a tooth with an artificial caries lesion. For simulation with monochromatic X-ray source, the relative error of lesion depth and thickness measurements of the remineralized layer was found to be 1%-2%. For polychromatic X-ray source, and omitting beam hardening correction, the relative error exceeded 6%. After appropriate beam-hardening correction, the relative error of the measurement could be reduced to 1%-2%. With the adjustment simulated in this study, microCT having polychromatic X-ray source resulted in the same level of error as with monochromatic source if the linearization method to correct the beam hardening was used. The presented simulation-based method is a useful way to determine artefact-caused distortions for other studies testing objects with different material and geometry.