Longitudinal assessment of dental erosion-abrasion by cross-polarization optical coherence tomography in vitro.

This study tested a novel in vitro dental erosion-abrasion model and the performance of cross-polarization optical coherence tomography (CP-OCT) in longitudinally monitoring the simulated lesions. Thirty human enamel specimens were prepared and randomized to receive three dental erosion-abrasion (EA) protocols: severe (s-EA, lemon juice/pH:2.5/4.25%w/v citric acid), moderate (m-EA, grapefruit juice/pH:3.5/1.03%w/v citric acid) and no-EA (water, control). EA challenge was performed by exposing the specimens to acidic solutions 4x/day and to brushing 2x/day with 1:3 fluoridated toothpaste slurry, for 14 days. Enamel thickness measurements were obtained using CP-OCT at baseline (D0), 7 (D7) and 14 days (D14) and micro-computed tomography (micro-CT) at D14. Enamel surface loss was measured with both CP-OCT and optical profilometry at D0, D7 and D14. Data was analyzed with repeated-measures ANOVA and Pearson's correlation (r) (α = 0.05). CP-OCT enamel thickness decreased over time in the s-EA group (D0 >D7 > D14, p < 0.001) and m-EA group (D0 > D14, p = 0.019) but did not change in the no-EA group (p = 0.30). Overall, CP-OCT and micro-CT results at D14 correlated moderately (r = 0.73). CP-OCT surface loss was highest for s-EA (p <0.001) but did not differ between moderate and no-EA (p = 0.25). Enamel surface loss with profilometry increased with severity (no-EA>m-EA>s-EA, p < 0.001). D14 surface loss was higher than D7 for both methods except for the no-EA group with profilometry. CP-OCT and profilometry had moderate overall correlation (r = 0.70). Our results revealed that the currently proposed in vitro dental erosion-abrasion model is valid and could simulate lesions of different severities over time. CP-OCT was a suitable method for monitoring the EA lesions.

Longitudinal assessment of dental erosion-abrasion by cross-polarization optical coherence tomography in vitro

Abstract: This study tested a novel in vitro dental erosion-abrasion model and the performance of cross-polarization optical coherence tomography (CP-OCT) in longitudinally monitoring the simulated lesions. Thirty human enamel specimens were prepared and randomized to receive three dental erosion-abrasion (EA) protocols: severe (s-EA, lemon juice/pH:2.5/4.25%w/v citric acid), moderate (m-EA, grapefruit juice/pH:3.5/1.03%w/v citric acid) and no-EA (water, control). EA challenge was performed by exposing the specimens to acidic solutions 4x/day and to brushing 2x/day with 1:3 fluoridated toothpaste slurry, for 14 days. Enamel thickness measurements were obtained using CP-OCT at baseline (D0), 7 (D7) and 14 days (D14) and micro-computed tomography (micro-CT) at D14. Enamel surface loss was measured with both CP-OCT and optical profilometry at D0, D7 and D14. Data was analyzed with repeated-measures ANOVA and Pearson's correlation (r) (α = 0.05). CP-OCT enamel thickness decreased over time in the s-EA group (D0 >D7 > D14, p < 0.001) and m-EA group (D0 > D14, p = 0.019) but did not change in the no-EA group (p = 0.30). Overall, CP-OCT and micro-CT results at D14 correlated moderately (r = 0.73). CP-OCT surface loss was highest for s-EA (p <0.001) but did not differ between moderate and no-EA (p = 0.25). Enamel surface loss with profilometry increased with severity (no-EA>m-EA>s-EA, p < 0.001). D14 surface loss was higher than D7 for both methods except for the no-EA group with profilometry. CP-OCT and profilometry had moderate overall correlation (r = 0.70). Our results revealed that the currently proposed in vitro dental erosion-abrasion model is valid and could simulate lesions of different severities over time. CP-OCT was a suitable method for monitoring the EA lesions.

Non-Biological and Biological Risk Indicators for Tooth Wear Outcomes in Adults.

This study was undertaken to estimate the prevalence and severity of tooth wear (TW), as well as to assess non-biological and biological risk indicators for TW outcomes in adults. A cross-sectional study, adhering to the reporting STROBE guidelines, was conducted and had a convenience sample of adults ≥18 years of age who had at least one bilateral posterior molar contact. A total of 570 participants, seeking consultation at the University Hospital in Brussels, Belgium, were allocated to three age groups: 18-34 years (n = 232), 35-54 years (n = 256), and ≥55 years old (n = 79). Participants answered a self-applied questionnaire regarding sociodemographics, oral hygiene, and lifestyle behavior. The questionnaire was tested-retested (intraclass correlation coefficient = 0.71). Inter-examiner reliability for clinical examinations was k = 0.76-0.80. The prevalence of TW was 75% (95% CI: 71.7-78.9). Out of these patients, 42% (95% CI: 38.0-46.3) had as the primary etiological factor the process of dental erosion, while 22% (95% CI: 18.9-25.9) and 11% (95% CI: 8.6-13.9) had the processes of dental attrition and dental abrasion, respectively. The severity of TW according to BEWE highest score was mild in 31%, moderate in 28%, and severe in 17% of participants. The hierarchical logistic regression model for the association between risk indicators and TW irrespective of the etiology was significant for age (>35-54 years: OR = 2.35 and ≥55 years: OR = 3.89; p < 0.001), gender (>male: OR = 2.03; p < 0.001), toothpaste (>sensitive teeth: OR = 2.34; p = 0.005), occlusal splint (>yes: OR = 1.62; p = 0.03), and acidic beverages (≥once per day: OR = 1.62; p = 0.044). Consumption of acidic beverages was not associated with TW having as the primary etiological factor the process of dental attrition or dental abrasion, while it was significantly associated with the process of dental erosion (>once per week: OR = 1.69; p = 0.043 and ≥once per day: OR = 1.73; p = 0.016). Medical conditions were equally associated with the latter (OR = 3.11; p < 0.001). These findings could contribute to improving the effectiveness and sustainability of awareness in contemporary adult populations. In conclusion, the prevalence and severity of TW in adults were substantial. Medical conditions and consumption of acidic beverages were risk indicators for TW having as the primary etiological factor the process of dental erosion, although associations were moderate and weak, respectively.

Tooth wear and oral-health-related quality of life in dentate adults.

OBJECTIVES: This study estimated the extent to which tooth wear, adjusted for (oral) health risk indicators, impacts adversely on the Oral-Health-Related Quality of Life (OHRQoL) of dentate adults. METHODS: A cross-sectional study was conducted and had a convenience sample of 570 adults ≥18 years old with at least one bilateral molar occlusal contact. Participants answered a self-applied questionnaire (ICC=0.71) consisting of four domains: socio-demographics, oral care attendance, (oral) health conditions and lifestyle, complaints and oral-health-related quality of life (OHIP-14). Tooth wear was clinically assessed using the Basic Erosive Wear Examination index by two examiners, whose inter-examiner reliability were k=0.76-0.80. RESULTS: The outcome was a high score on the OHRQoL (median split ≥ 7). The prevalence of tooth wear was 75.0%. Only 30.2% of adults reported impacts on at least 1 performance parameter affected 'fairly often' or 'very often'. The hierarchical logistic regression showed that participants 35-54 years old (OR=2.1), who were ever prevented from regular oral health care due to costs of care (OR=3.6), who ingested acidic beverages ≥ daily (OR=1.7), who had tooth sensitivity (OR= 2.9) and those having the impression that their teeth have changed appearance (OR= 5.9) were significantly more likely to report lower OHRQoL than their counterparts. The severity of tooth wear was not significant when considering moderate and severe cases together. CONCLUSIONS: Although the prevalence of tooth wear was high, its severity and impact on OHRQoL were limited. However, distal and proximal indicators for tooth wear were mediators for impaired OHRQoL and treatment needs. CLINICAL SIGNIFICANCE: Prevalence and severity of tooth wear had limited impact on OHRQoL in adults. Distal and proximal indicators for tooth wear were mediators for impaired OHRQoL. The understanding of these relationships offers an opportunity to assess in depth the treatment needs and quality of life of patients affected by tooth wear.

Enamel crack association with tooth age and wear severity: An optical coherence tomography study.

PURPOSE: To investigate the association of dental enamel cracks with estimated tooth age and varying tooth wear severities. METHODS: 355 premolars were sorted from a pool of extracted human teeth, based on their estimated age range: 21-40, 41-60 years old, determined by a dental forensic method and on the presence/severity of lesions: none, mild, moderate and severe wear (Basic Erosive Wear Examination Index). The buccal and lingual surfaces of the teeth were inspected for cracks under an optical coherence tomography system. Images were evaluated according to the following scores: 0= no crack; 1= crack beginning and terminating within the enamel, not reaching the outer surface; 2= crack extending from outer enamel surface terminating within the enamel; 3= crack extending from within enamel terminating at or beyond the dentin-enamel junction (DEJ); 4= crack extending from outer enamel surface terminating at or beyond the DEJ. Data were analyzed by Spearman correlations and Mantel-Haenszel chi-square tests. RESULTS: Estimated tooth age and crack score were moderately correlated. Crack scores increased between each range of estimated tooth age (P< 0.050). Occlusal surfaces showing moderate or severe wear had higher buccal crack scores than occlusal surfaces having no wear (P< 0.020) and mild wear (P< 0.001). Buccal surfaces presenting severe wear had higher buccal crack scores than buccal surfaces with no wear, mild or moderate wear (P< 0.001). Premolars having severe wear had significantly higher crack scores than premolars showing no, mild or moderate wear lesions. CLINICAL SIGNIFICANCE: Knowing that older and more severely worn teeth are more prone to enamel cracks allows clinicians to better diagnose, monitor, and prevent further damage to teeth.

Caries Detection around Restorations Using ICDAS and Optical Devices.

PURPOSE: Secondary caries is the major reason for replacement of restorations in operative dentistry. New detection methods and technology have the potential to improve the accuracy for diagnosis of secondary carious lesions. This in vitro study evaluated the performance of the ICDAS (International Caries Detection and Assessment System) visual criteria and optical devices for detecting secondary caries around amalgam and composite resin restorations in permanent teeth. MATERIALS AND METHODS: A total of 180 extracted teeth with Class I amalgam (N = 90) and resin composite (N = 90) restorations were selected. Two examiners analyzed the teeth twice using the visual criteria (ICDAS), laser fluorescence (LF), light-emitting diode device (MID), quantitative light-induced fluorescence system (QLF), and a prototype system based on the Fluorescence Enamel Imaging technique (Professional Caries Detection System, PCDS). The gold standard was determined by means of confocal laser scanning microscopy. RESULTS: High-reproducibility values were shown for all methods, except for MID in the amalgam group. For both groups the QLF and PCDS were the most sensitive methods, whereas the other methods presented better specificity (p < 0.05). CONCLUSION: All methods, except the MID device appeared to be potential methods for detecting secondary caries only around resin composite restorations, whereas around amalgam restorations all methods seemed to be questionable. CLINICAL SIGNIFICANCE: Using Internal Caries Detection and Assessment System (ICDAS), an LF device, quantitative light-induced fluorescence and a novel method based on Fluorescence Enamel Imaging technique may be effective for evaluating secondary caries around composite resin restorations.

Effect of intracanal medicaments used in endodontic regeneration procedures on microhardness and chemical structure of dentin.

OBJECTIVES: This study was performed to investigate the effects of different intracanal medicaments on chemical structure and microhardness of dentin. MATERIALS AND METHODS: Fifty human dentin discs were obtained from intact third molars and randomly assigned into two control groups and three treatment groups. The first control group received no treatment. The second control group (no medicament group) was irrigated with sodium hypochlorite (NaOCl), stored in humid environment for four weeks and then irrigated with ethylenediaminetetraacetic acid (EDTA). The three treatment groups were irrigated with NaOCl, treated for four weeks with either 1 g/mL triple antibiotic paste (TAP), 1 mg/mL methylcellulose-based triple antibiotic paste (DTAP), or calcium hydroxide [Ca(OH)2] and finally irrigated with EDTA. After treatment, one half of each dentin disc was subjected to Vickers microhardness (n = 10 per group) and the other half was used to evaluate the chemical structure (phosphate/amide I ratio) of treated dentin utilizing attenuated total reflection Fourier transform infrared spectroscopy (n = 5 per group). One-way ANOVA followed by Fisher's least significant difference were used for statistical analyses. RESULTS: Dentin discs treated with different intracanal medicaments and those treated with NaOCl + EDTA showed significant reduction in microhardness (p < 0.0001) and phosphate/amide I ratio (p < 0.05) compared to no treatment control dentin. Furthermore, dentin discs treated with TAP had significantly lower microhardness (p < 0.0001) and phosphate/amide I ratio (p < 0.0001) compared to all other groups. CONCLUSIONS: The use of DTAP or Ca(OH)2 medicaments during endodontic regeneration may cause significantly less microhardness reduction and superficial demineralization of dentin compared to the use of TAP.

Validity of caries detection on occlusal surfaces and treatment decisions based on results from multiple caries-detection methods.

The aim of this in vitro study was to evaluate whether having results available from multiple detection methods influences dentist's treatment decisions for incipient caries lesions on occlusal surfaces. The occlusal surface of 96 extracted permanent molars without frank cavitation was examined by three examiners initially by visual examination alone, following which they chose one of three treatment options: (i) no treatment, (ii) preventive or non-invasive treatment (sealants), and (iii) invasive treatment. Four weeks later the examiners again selected one of the three treatment options for the surfaces, but this time were able to refer to the results from additional caries-detection methods [bitewing radiographs, electric conductance measurement (ECM), quantitative light fluorescence (QLF), and DIAGNOdent] that had been performed in the interim time. Stereomicroscopy was used to evaluate sensitivity, specificity, accuracy, and area under the Receiver Operating Characteristic (ROC) curve (AUC) for the detection methods at the D1 diagnostic threshold. Slight improvement was obtained in the percentage of sites correctly diagnosed, and in the AUC, when referring to the results obtained from all detection methods compared with visual examination alone. However, a drastic effect on the selection of treatment options was observed by having results available from multiple methods, with the choice of invasive treatment increasing substantially. In conclusion, having data available from multiple methods did not improve the accuracy of examiners in detecting early occlusal caries lesions, but it had a great influence on the number of surfaces indicated for operative treatment. The potential decrease in overall specificity while using multiple methods of detection may be of concern in populations with a low prevalence of occlusal caries lesions.