Effect of pit and fissure sealants on caries detection by a fluorescent camera system

Objective

The aim of this study was to evaluate the effect of sealant placement on the detection of caries by a fluorescent camera (FC), the Spectra caries detector.

Materials and methods

In a laboratory study, FC images and readings were obtained from 31 extracted teeth, before and following application of clear sealants (Shofu Clear or Delton unfilled), or opaque sealants (3M Clinpro or Delton FS). Teeth were then sectioned and examined for enamel or dentine caries. Using each tooth's true caries diagnosis, the sensitivity and specificity of the FC measurements in detecting dentine caries was calculated. In the clinical study, FC readings were obtained from 41 molars in children prior to and following application of clear sealants.

Results

Following application of Shofu or Delton unfilled there were reductions in the mean FC readings of 10% (p = 0.5) and 8.2% (p = 0.009), respectively. Application of two opaque sealants, 3M or Delton FS significantly reduced mean FC readings 16.2% and 20.8% (p < 0.5), respectively. Although the carious lesions could still be observed in FC images from teeth with opaque sealants there was a significant loss of sensitivity in detecting dentinal caries. Clear sealant application caused an insignificant loss of detection sensitivity. Following application of clear sealants to children's molars there was a small (4.01%) but significant (p < 0.01) reduction in FC readings recorded from these teeth.

Conclusions

The FC can detect caries under clear sealants with little loss of sensitivity. Although lesions can be seen through opaque sealants, loss of sensitivity precludes accurate lesion assessment.     

Caries detection under composite restorations by laser fluorescence and digital radiography

Objectives

The objective of this study is to assess the potential of DIAGNOdent readings in detecting carious lesions under composite resin restorations in comparison with digital radiography.

Materials and methods

One hundred extracted third molars were visually selected: 50 with and 50 without carious lesions. Class I occlusal cavities were prepared. In the carious group, caries were left on the floor of cavities before composite resin restoration. The occlusal surface relevant to the caries position in the carious group and a counterfeit point in the non-carious group were marked for DIAGNOdent reading. Teeth were fixed in a plaster box. Digital radiographs were taken and examined by four observers. Definitive diagnosis of caries was based on a histological assessment. Diagnostic accuracy for each method was expressed by the area under the receiver operating characteristic (ROC) curve. Differences between the areas under the ROC curves were assessed using the McNemar test.

Results

The respective sensitivity (95 % confidence interval (%CI)) and specificity (95 %CI) of DIAGNOdent were 0.74 (0.66–0.83) and 0.84 (0.76–0.92). The respective average diagnostic performance values for digital radiographs assessed by four observers were 0.54 (0.36–0.72) and 0.77 (0.65–0.86). The respective ROC values for DIAGNOdent and digital radiographs based on four observers were 0.79 and 0.65. Cohen’s kappa statistic revealed a moderate to substantial agreement among interobserver reliabilities (k?=?0.60–0.77).

Conclusions

There were no statistically significant differences between DIAGNOdent and digital radiographs for the detection of dental caries under composite restoration (p value?>?0.05).

Clinical relevance

DIAGNOdent was developed to detect caries on occlusal surfaces and was tested for caries adjacent to filling materials. This study demonstrated the use of DIAGNOdent in detecting caries under old composite restorations.     

Relationship between daily habits, Streptococcus mutans, and caries among schoolboys

Objectives

The purpose of this study was to examine the associations between daily habits, Streptococcus mutans, and caries using International Caries Detection and Assessment System Caries Index (ICDAS CI); and compare it to the DMF index.

Subjects and methods

Altogether 122 children were examined and interviewed. Saliva and plaque samples were collected and analyzed by Dentocult SM^® Strip Mutans test. ICDAS CI was calculated by counting all ICDAS caries scores of all surfaces divided by total number of carious teeth.

Results

ICDAS CI was significantly (p < 0.01) and strongly associated with DMFT/dmft (ρ = 0.72), DMFS/dmfs (ρ = 0.72), total number of carious teeth (DT/dt) (ρ = 0.77), enamel caries surfaces (ρ = 0.61) and dentine caries surfaces (ρ = 0.75). Plaque S. mutans was significantly (p < 0.05) correlated with ICDAS CI and DT/dt. Children who brushed once a day or more had significantly lower ICDAS CI (p < 0.01). Children who consumed sweets or drank soft drinks more than once a day had significantly higher ICDAS CI (p < 0.05). No significant association was found between ICDAS CI and frequency of flossing, use of mouthrinse, or gum chewing.

Conclusion

ICDAS CI seems to have similar trends as DMF indices, but includes more information about the stage, severity, and progress of the caries lesions of the patient.     

Validity of caries risk assessment programmes in preschool children

Objectives

Various programmes have been developed for caries risk assessment (CRA). Nevertheless, scientific evidence on their validity is lacking. This study aimed to compare the validity of 4 CRA programmes (CAT, CAMBRA, Cariogram, and NUS-CRA) in predicting early childhood caries.

Methods

A total of 544 children aged 3 years underwent oral examination and biological tests (saliva flow rate, salivary buffering capacity and abundance of cariogenic bacteria mutans Streptococci and Lactobacilli). Their parents completed a questionnaire. Children's caries risk was predicted using the 4 study programmes without biological tests (screening mode) and with biological tests (comprehensive mode). After 12 months, caries increment in 485 (89%) children was recorded and compared with the baseline risk predictions.

Results

Reasoning-based programmes (CAT and CAMBRA screening) had high sensitivity (≥93.8%) but low specificity (≤43.6%) in predicting caries in children. CAMBRA comprehensive assessment reached a better balance (sensitivity/specificity of 83.7%/62.9%). Algorithm-based programmes (Cariogram and NUS-CRA) generated better predictions. The sensitivity/specificity of NUS-CRA screening and comprehensive models were 73.6%/84.7% and 78.1%/85.3%, respectively, higher than those of the Cariogram screening (62.9%/77.9%) and comprehensive assessment (64.6%/78.5%). NUS-CRA comprehensive model met the criteria for a useful CRA tool (sensitivity + specificity ≥ 160%), while its screening model approached that target.

Conclusions

Our results supported algorithm-based approach of caries risk modelling and the usefulness of NUS-CRA in identifying children susceptible to caries.

Clinical significance

This prospective study provided evidence for practitioners to select tools for assessing children's caries risk, so that prevention measures can be tailored and treatment plan can be optimised.     

Clinical performance of a new laser fluorescence device for detection of occlusal caries lesions in permanent molars

Objectives

To determine the clinical performance of a laser fluorescence device (DIAGNOdent pen, KaVo) to discriminate between different occlusal caries depths (D₀–D_1–4; D_0–2–D_3,4) in permanent molars.

Methods

In this prospective, randomized two-centre-study 120 sound/uncavitated carious sites in 120 patients were measured after visual and radiographic caries assessment. In cases of operative intervention (n = 86), the lesion depths after caries removal were recorded (reference). In cases of preventive intervention (n = 34), the sites were reassessed visually/radiographically after 12 months to verify the status assessed before (reference). The discrimination performance was determined statistically (Mann–Whitney test, Spearman’s rho coefficient, and areas under the receiver operating characteristic curves (AUCs)). Sensitivities (SE) and specificities (SP) were plotted as a function of the measured values and cut-off values for the mentioned thresholds suggested.

Results

Sound sites (n = 13) had significantly minor fluorescence values than carious sites (n = 107) (P < 0.0001) as had sites with no/enamel caries (n = 63) compared to dentinal caries (n = 57). The AUCs for the same discriminations were 0.92 and 0.78 (P < 0.001). For the D₀–D_1–4 threshold, a cut-off at a value of 12 (SE: 0.88, SP: 0.85) and for the D_0–2–D_3,4 threshold at 25 (SE: 0.67, SP: 0.79) can be suggested. A moderate positive correlation between the measurements and the caries depths was calculated (rho = +0.57, P = 0.01).

Conclusion

Within this study, the device’s discrimination performance for different caries depths was moderate to very good and it may be recommended as adjunct tool in the diagnosis of occlusal caries.     

Validity of MicroCT for in vitro detection of proximal carious lesions in primary molars

Objective

This study aimed to validate the MicroCT for detection of proximal carious lesions in primary molars, using histology as the gold standard.

Methods

Forty-eight proximal surfaces of primary molars were examined. Two calibrated examiners conducted the examinations independently. Proximal surfaces were visually scored, using ICDAS. Bitewing radiographs, Micro-CT and histological analyses used caries scores: 0 = sound; 1 = outer enamel; 2 = inner enamel; 3 = not spread dentine; 4 = outer dentine; 5 = inner dentine. Axial and sagital images were used for Micro-CT analysis, whilst for histology, tooth sections (400 μm) were analyzed stereomicroscopically (×15).

Results

Inter-examiner agreement ranged from 0.87 to 0.93 kappa coefficient (k). Histological analysis revealed a frequency of sound tooth surfaces (18.8%) enamel carious lesions (E1) (48%) and dentine carious lesions (D1) (33.3%). MicroCT showed high correlation with histology (r_s0.88). At both diagnostic thresholds (E1 and D1), sensitivity and accuracy were higher for MicroCT. Inter-device agreement between MicroCT and histology was k = 0.81. No difference was found between MicroCT and histology as gold standards for detecting carious lesions using ICDAS.

Conclusion

MicroCT can be used as a gold standard for detecting carious lesions in proximal surfaces in primary molars.     

Diagnostic performance of the visual caries classification system ICDAS II versus radiography and micro-computed tomography for proximal caries detection: An in vitro study

Objectives

The purpose of this study was: (a) to compare the visual caries classification system ICDAS II with conventional (CR) and digital radiography (DR) for diagnosis of non-cavitated caries on free proximal surfaces, (b) to examine the potential of micro-computed tomography (MCT) to substitute histological examination for the in vitro caries assessment.

Methods

Both proximal surfaces of 20 teeth received classification separately by two examiners by means of the diagnostic modalities examined. The teeth were sectioned and assessed for depth of the lesion. The modalities were compared in terms of degree of inter-examiner agreement, sensitivity, specificity, accuracy, positive and negative predictive value and validity. Two diagnostic thresholds were applied: no caries versus all caries scores (D1), and no dentin caries versus dentin caries (D3).

Results

The weighted kappa values for inter-examiner reproducibility for all diagnostic modalities were 0.51–0.81. Visual examination (ICDAS II) reached significant higher sensitivity (0.92–0.96) and negative predictive value (0.9–1) than radiography. Likewise, the radiographic modalities presented significantly higher specificity (0.93–1) and positive predictive values (0.92–1) than the ICDAS II criteria. The overall accuracy performance of radiographic modalities was related to the diagnostic threshold. MCT did not agree with histological validation at each disease severity scale.

Conclusions

The ICDAS II criteria are a promising tool for caries diagnosis on free proximal surfaces. DR and CR radiography present comparable performance. Furthermore, MCT is not capable of constituting a reliable alternative to histological examination for caries research.     

The prevalence and distribution of dental caries in four early medieval non-adult populations of different socioeconomic status from Central Europe

Objectives

The aim of the study was to map the dental health status in non-adult individuals and to verify whether and how the existence of caries in the non-adult age group is associated with the different socio-economic status of early medieval populations.

Material and methods

We studied the dental remains from the acropolis of the Mikul?ice settlement agglomeration, where members of the higher social classes were buried, and from the Mikul?ice hinterland. Overall, we evaluated 2544 teeth/3714 alveoli of deciduous dentition and 1938 teeth/2128 alveoli of permanent dentition. We determined the number of individuals with dental caries (i.e., caries frequency index, F-CE) and the proportion of teeth/alveoli with caries/ante-mortem tooth loss (i.e., caries intensity index, I-CE).

Results

We found no statistical significant difference in the F-CE values between the Mikul?ice hinterland and the acropolis. In addition, we found no statistically significant difference in the proportion of teeth with carious lesions (I-CE) either in the case of deciduous dentition or in the case of permanent dentition between the hinterland and the acropolis. In the case of permanent dentition, the statistically significant highest proportion of carious lesions (I-CE) was found in Mikul?ice I (p ≤ 0.05). We confirmed an increase in the rate of caries with age.

Conclusions

The level of caries at all of the studied medieval locations was very low. We presume that lifestyle and the associated dietary habits and hygienic practices of the individuals or population groups had a greater influence on dental caries than did the socio-economic status of these individuals.     

Evaluating performance of dental caries detection methods among third-year dental students

Background

Reliable caries detection is a cornerstone in the modern caries treatment schema. This study aimed to evaluate adopting traditional and new caries detection methods by third-year dental students.

Methods

Fifty-seven students were given lectures on caries detection, after which they evaluated 27 extracted carious teeth using traditional clinical assessment (CE), Nyvad’s, and ICDAS methods. On three teeth they also performed DIAGNOdent pen® (LF) scanning. Histological scores of the sectioned teeth (ICDAS, LF) and activity estimations of the lesions by the supervisors were used as golden standards (Nyvad, CE). For the ICDAS method , sensitivity and specificity were calculated using dentine caries (D3) as a cut-off point. Mean ICC and kappa values were calculated to evaluate interexaminer agreement for all lesions and methods. Spearman’s correlation coefficient evaluated LF scanning.

Results

ICDAS method presented good sensitivity ( 0.78) and specificity (0.87). The inter-examiner agreement for different methods was fair or good (CE ICC?=?0.69, κ?=?0.53; Nyvad’s method ICC?=?0.68, κ?=?0.48, ICDAS ICC?=?0.66, κ?=?0.47). Variation in LF values was the greatest with lesions extending to middle third of dentin. In that case, the Spearman’s correlation coefficient was also the weakest.

Conclusions

To follow the guidelines by the European Core Curriculum on Cariology, the third year dental students are introduced to methods for detecting lesion depth and assessing lesion activity as well as using new caries detection methods. Their performance in estimating lesion depth is good, and fair to good in estimating lesion activity even after basic training only.

     

Marginal integrity and secondary caries of selectively excavated teeth in vitro

Objectives

Selective caries removal involves sealing of carious dentine beneath restorations, which might decrease their marginal integrity and increase the susceptibility for secondary caries and microleakage. The present study compared these marginal characteristics of restorations in selectively and completely excavated teeth.

Methods

In 32 premolars, shallow and deep artificial lesions were created on pulpo-axial walls of mesial-distal-occlusal cavities, with mesial and distal margins located in enamel and dentine, respectively. Demineralised dentine was either removed or left before adhesively restoring the teeth (n = 8), which were then submitted to thermo-mechanical cycling. The integrity of gingivo-cervical margins was assessed using scanning electron microscopy. In half of each margin, caries was induced adjacent to restorations using a continuous-culture biofilm model, and resulting lesions were evaluated using transversal microradiography. The other half of each margin was used to assess microleakage.

Results

Integrity or microleakage of margins located in enamel did not differ significantly between groups, and bacterial biofilms did not induce distinct caries lesions in enamel. Dentinal margins in teeth with deep compared with shallow lesions showed a significantly higher proportion of marginal imperfections, gaps and microleakage (p ≤ 0.05, Mann–Whitney/χ²-test). In contrast, neither marginal integrity nor microleakage differed significantly between completely and selectively excavated teeth (p > 0.05). Dentinal mineral loss adjacent to restorations did not differ significantly between groups (p > 0.80).

Conclusions

The marginal characteristics of restorations were affected by the depth of sealed or excavated lesions, but not by the performed caries excavation. This study did not find selective excavation detrimental for restoration integrity in vitro.

Clinical significance

Selective excavation of deep lesions was shown to reduce pulpal risks, whilst leaving caries beneath restorations is feared to compromise the marginal characteristics of the subsequently placed restoration. Based on the present in vitro study, such assumptions cannot be supported.     

Conventional caries removal and sealed caries in permanent teeth: a microbiological evaluation

Objectives

The aim of this study was to compare microbiological infection after conventional carious dentine removal with incomplete carious dentine removal and sealing.

Methods

Eighty-seven patients (12–50 years of age) under treatment at the Dental Clinics of the Federal University of Rio Grande do Sul (UFRGS), Brazil, participated in the study. The patients presented 90 posterior permanent teeth with primary caries. The lesions were coronal, active, and reached at least the middle third of the dentine. None of the teeth exhibited spontaneous pain, sensitivity to percussion or apical pathology (detected through radiographic exams). Pulp sensibility was confirmed by the cold test. The lesions were divided into 2 experimental groups: complete caries removal (CCR) based on hardness criteria (n = 60 lesions) and incomplete caries removal (ICR) and sealing (n = 32 lesions). Microbiological samples were obtained from the initial demineralized dentine, after CCR and after ICR-Seal.

Results

The number of anaerobic and aerobic bacteria, lactobacilli, and mutans streptococci decreased at the end of treatment (p < 0.05). Significantly less anaerobic bacteria (p < 0.01), aerobic bacteria (p = 0.02), and mutans streptococci (p < 0.01) growth was observed after ICR-Seal compared to CCR. The difference in lactobacilli was insignificant (p = 0.08). The amount of bacteria detected after conventional caries removal was higher than that which remained in sealed caries lesions.

Conclusions

The results suggest it is not necessary to remove all carious dentine before the restoration is placed because over time, sealing of carious dentine results in lower levels of infection than traditional dentine caries removal.

Clinical significance

The results of this study indicate that sealed carious dentine was less infected than the remaining dentine left after conventional caries removal and sealing. Our results support treatment of deep carious lesions in one session with incomplete removal of carious dentine.     

An ex vivo study of arrested primary teeth caries with silver diamine fluoride therapy

Objectives

This ex vivo study compared the physico-chemical structural differences between primary carious teeth biannually treated with silver diamine fluoride (SDF) and carious teeth without such treatment.

Method

Twelve carious primary upper-central incisors were collected from 6-year-old children. Six teeth had arrested caries after 24-month biannual SDF applications and 6 had active caries when there was no topical fluoride treatment. The mineral density, elemental contents, surface morphology, and crystal characteristics were assessed by micro-computed tomography (micro-CT), energy-dispersive X-ray spectrometry (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).

Results

Micro-CT examination revealed a superficial opaque band approximately 150 μm on the arrested cavitated dentinal lesion. This band was limited in the active carious lesion. EDX examination detected a higher intensity of calcium and phosphate of 150 μm in the surface zone than in the inner zone, but this zone was restricted in the active cavitated dentinal lesion. SEM examination indicated that the collagens were protected from being exposed in the arrested cavitated dentinal lesion, but were exposed in the active cavitated dentinal lesion. TEM examination suggested that remineralised hydroxyapatites were well aligned in the arrested cavitated dentinal lesion, while those in the active cavitated dentinal lesion indicated a random apatite arrangement.

Conclusions

A highly remineralised zone rich in calcium and phosphate was found on the arrested cavitated dentinal lesion of primary teeth with an SDF application. The collagens were protected from being exposed in the arrested cavitated dentinal lesion.

Clinical significance

Clinical SDF application positively influences dentine remineralisation.     

In vitro performance of DIAGNOdent laser fluorescence device for dental calculus detection on human tooth root surfaces

Objective

This study assessed the reproducibility of a red diode laser device, and its capability to detect dental calculus in vitro on human tooth root surfaces.

Effect of chlorhexidine-thymol varnish on root caries in a geriatric population: A randomized double-blind clinical trial

Objectives

Little is known about the effect of Cervitec^®, a chlorhexidine-thymol varnish, on root caries. Our objective was to determine whether a 3-monthly application of Cervitec^® over 1 year would limit the progress of existing root caries lesions and reduce the incidence of dental root caries in a group of dentate institutionalized elderly, as a complement to their usual oral hygiene practices.

Methods

A double-blind randomized clinical trial was conducted in 68 subjects (34 per group) in two residences in Almería (Spain). Twenty-one subjects with 60 root caries lesions and 25 with 65 lesions, in the Cervitec^® and placebo groups, respectively, completed the study. Varnishes were applied twice in the first week, 1 month later, and every 3 months until the end of the study. Clinical parameters associated with established lesions were determined at baseline and after 6 and 12 months, as was the incidence of root caries lesions.

Results

The clinical evolution of lesions was significantly better in the Cervitec^® group as opposed to the placebo group in terms of width, height, color, and texture. The increase in root caries was significantly lower (p = 0.039) in the Cervitec^® group.

Conclusion

According to these results, Cervitec^® may help to control established root lesions and reduce the incidence of root caries lesion among institutionalized elderly.     

An in vitro evaluation of microtensile bond strengths of two adhesive bonding agents to residual dentine after caries removal using three excavation techniques

Objectives

To assess amounts of residual dentine retained after using three excavation techniques; the microtensile bond strengths (μTBS) to residual dentine, comparing etch-rinse vs. self-etching adhesives.

Methods

42 carious molars were subdivided (N = 21) dependent upon adhesive/composite system (Adper Scotchbond 1XT and Filtek Supreme vs. Filtek Silorane adhesive and composite). Dividing into three (N = 7), dependent upon caries excavation technique employed (hand vs. chemo-mechanical: Carisolv™ gel vs. experimental enzymatic gel (SFC-V)), caries removal was assessed using visual/tactile criteria and in situ autofluorescence (AF) confocal fibre-optic micro-endoscopy (CFOME). Post-restoration/four-week hydrated storage, four 0.9 mm² beams per tooth underwent μTBS testing/microscopic analysis of fractured surfaces. Three cavities from each excavation group were analysed using SEM.

Results

SEM revealed surface roughness with smear layer occluding tubule orifices in hand-excavated samples and a reduced, variable smear layer for both chemo-mechanical systems. CFOME AF assessment indicated hand excavation left sound dentine, Carisolv™ left affected dentine and SFC-V slightly under-prepared clinically. Mean μTBS values from etch-rinse samples (27 MPa (SD 3.9), hand; 22 MPa (SD 5.1), Carisolv™; 26 MPa (SD 4.4), SFC-V) showed statistical differences between hand and Carisolv™ groups. Mean μTBS data for self-etch samples (22 MPa (SD 3.3), hand; 27 MPa (SD 6.1), Carisolv™; 25 MPa (SD 4.7), SFC-V) showed significant differences between hand and Carisolv™, and hand vs. SFC-V. Failure loci distribution in etch-rinse samples was between dentine–adhesive, within adhesive and within composite whereas self-etch samples exhibited failure predominantly between adhesive and composite.

Conclusions

Data indicated that all null hypotheses were disproved.     

Is non-cavitated proximal lesion sealing an effective method for caries control in primary and permanent teeth? A systematic review and meta-analysis

Objectives

The aim of this study was to perform a systematic review and meta-analysis on the effectiveness of sealing non-cavitated proximal caries lesions in primary and permanent teeth.

Data

Only controlled clinical trials and randomized controlled clinical trials that evaluated the effectiveness of sealing on non-cavitated proximal caries with a minimum follow-up of 12 months were included in the study. The primary outcome should be arrestment/progression of proximal caries evaluated by bitewing radiographs. A risk of bias evaluation based on the Cochrane Collaboration common scheme for bias was carried out for each study. The meta-analysis was performed on the studies considered low risk of bias and with pair-wise visual reading results through RevMan software.

Sources

A comprehensive search was performed in the Systematic Electronic Databases: Pubmed, Cochrane Library, Scopus, IBI Web of Science, Lilacs, SIGLE, and on website Clinical trials.gov, through until June 2013.

Study selection

From 967 studies identified, 10 articles and 3 studies with partial results were assessed for eligibility. However three articles were excluded and our final sample included 10 studies. According to the risk of bias evaluation, six studies were considered “high” risk of bias, and four “low” risk of bias. The forest plot of the meta-analysis showed low heterogeneity (I² = 29%) and a favourable outcome for the Infiltrant. The chance of caries progression when this technique was used was significantly lower (p = 0.002) compared with Placebo.

Conclusion

Our results suggest that the technique of sealing non-cavitated proximal caries seems to be effective in controlling proximal caries in the short and medium term. Further long-term randomized clinical trials are still necessary to increase this evidence.

Clinical significance

Contemporary dentistry is focused in minimally invasive approaches that prevent the destruction of sound dental tissues next to carious lesions. This paper searches for evidence of the efficacy of sealing/infiltrating non-cavitated proximal caries in arresting caries progression both in permanent and primary teeth.     

Clinical evaluation of polypropylene glycol-based caries detecting dyes for primary and permanent carious dentin

Objective

The aim of this study was to compare the clinical efficacy of new caries detecting dye Caries Check Blue (CCB) with Caries Check (CC) and Caries Detector (CD) using a laser fluorescence device (DIAGNOdent).

Method

Primary and permanent teeth with dentin caries were stained with polypropylene glycol (MW = 300) based new caries detecting dyes CCB, CC, or propylene glycol (MW = 76) based CD. In the CCB and CC groups, stained dentin was completely removed. In the CD groups, pink-stained dentin was retained according to the manufacturers’ instructions. Cavities before and after caries removal were measured with the DIAGNOdent. Data were analyzed using ANOVA and Fisher’s PLSD multiple comparison test at α = 0.05. Regression analyses were performed between DIAGNOdent readings and scores obtained from the clinical parameters.

Results

The DIAGNOdent readings after caries removal were: primary-CCB (13.2 ± 10.4), primary-CC (14.3 ± 16.7), primary-CD (9.0 ± 5.2), permanent-CCB (22.7 ± 13.4), permanent-CC (10.6 ± 6.8) and permanent-CD (9.7 ± 9.0). Significant differences were identified between the permanent-CCB and all other groups. Correlation coefficients between DIAGNOdent readings and clinical parameters were low.

Conclusions

When dentin stained with Caries Check Blue or Caries Check was completely removed, the DIAGNOdent readings were higher than those recorded when palely-stained pink dentin was retained with the Caries Detector, with significant difference observed for the permanent-CCB group. Caries Check Blue may be used clinically to avoid excessive removal of caries-affected or sound dentin in permanent teeth but not in primary teeth.     

Incipient caries lesions on cementum by mono- and co-culture oral bacteria

Objectives

There is increasing prevalence of root caries. We hypothesized different biofilms will cause varying demineralization in cementum. This study investigated the extent of demineralization of cementum by oral biofilm formed from three major cariogenic microorganisms: Streptococcus mutans, Lactobacillus acidophilus, and Actinomyces israelii. Sound cementum tooth blocks were incubated with mono-, bi-, and tri-species combinations of the bacteria under investigation.

Materials and methods

The matrix (amide I) and phosphate content of the lesions was analyzed by Fourier-transform infrared spectroscopy (FTIR), and calcium and phosphorus levels were analyzed by scanning electron microscopy and energy-dispersive spectroscopy (SEM-EDX).

Results

The log[amide I:HPO₄²⁻ absorbance] values showed that A. israelii mono-culture caused significantly more demineralization than the other bacterial cultures. log[Ca:P] showed that all carious lesions were confined to the cementum.

Conclusions

Oral biofilm arising from bacterial species A. israelii alone was the most cariogenic of those tested and produced the most demineralization in incipient carious lesions in cementum.     

Dentine microhardness after different methods for detection and removal of carious dentine tissue

There are several methods for identifying carious dentinal tissue aiming to avoid removal of healthy dentinal tissue.

Objectives

The purpose of this study was to test different methods for the detection of carious dentinal tissue regarding the amount of carious tissue removed and the remaining dentin microhardness after caries removal.

Material and methods

The dentin surfaces of 20 bovine teeth were exposed and half of the surface was protected with nail polish. Cariogenic challenge was performed by immersion in a demineralizing solution for 14 days. After transverse cross-section of the crown, the specimens were divided into four groups (n=10), according to the method used to identify and remove the carious tissue: "Papacárie", Caries-detector dye, DIAGNOdent and Tactile method. After caries removal, the cross-sectional surface was included in acrylic resin and polished. In a microhardness tester, the removed dentin thickness and the Vickers microhardness of the following regions were evaluated: remaining dentin after caries removal and superficial and deep healthy dentin.

Results

ANOVA and Tukey''s test (α=0.05) were performed, except for DIAGNOdent, which did not detect the presence of caries. Results for removed dentin thickness were: "Papacárie" (424.7±105.0; a), Caries-detector dye (370.5±78.3; ab), Tactile method (322.8±51.5; bc). Results for the remaining dentin microhardness were: "Papacárie" (42.2±10.5; bc), Caries-detector dye (44.6±11.8; abc), Tactile method (24.3±9.0; d).

Conclusions

DIAGNOdent did not detect the presence of carious tissue; Tactile method and "Papacárie" resulted in the least and the most dentinal thickness removal, respectively; Tactile method differed significantly from "Papacárie" and Caries-detector dye in terms of the remaining dentin microhardness, and Tactile method was the one which presented the lowest microhardness values.     

Minimally invasive caries removal using bio-active glass air-abrasion

Objectives

Alumina air-abrasion has been used to clean teeth and shown to over-prepare access cavity preparation to caries. This study investigated the working hypothesis that bio-active glass air-abrasion is more self-limiting than alumina for minimally invasive caries removal.

Methods

Human extracted molars were scored visually using ICDAS II criteria, divided into sound and carious groups and air-abraded with alumina (n = 10) and bio-active glass (n = 10) in each group, using identical operating parameters. The amount of enamel removed was semi-quantitatively assessed using scanning electron microscopy. Operating time was recorded.

Results

Bio-active glass abrasion removed extrinsic stain and substantial quantities of enamel from all carious fissures but not from sound, where only minimal microscopic surface modifications were observed. Alumina air-abrasion resulted in faster extrinsic stain and clinically substantial enamel removal in both sound and carious groups equally.

Conclusions

Bio-active glass air-abrasion appeared to show a significant self-limiting tendency towards demineralised enamel and extrinsic stain removal but was slower in comparison to alumina air-abrasion. Self-limiting bio-active glass air-abrasion could be used clinically to clean teeth, detect caries and minimally prepare carious enamel as part of MI caries access or placing a sealant restoration.