Comparison of the accuracy of intraoral scanners, intraoral cameras, radiographs, and histological methods for the diagnosis of dental caries: a systematic review and meta-analysis

Data sourcesMedline, Embase, Cochrane Central and grey literature, complemented by cross-referencing from bibliographies. Diagnostic reviews were searched using the Medion database.Study selectionStudies reporting on the accuracy (sensitivity/specificity) of radiographic detection of primary carious lesions under clinical (in vivo) or in vitro conditions were included. The outcome of interest was caries detection using radiographs. The study also assessed the effect of the histologic lesion stage and included articles to assess the differences between primary or permanent teeth, if there had been improvements recently due to technical advances or radiographic methods, or if there are variations within studies (between examiners or applied radiographic techniques).Data extraction and synthesisData extraction was done by one reviewer first, using a piloted electronic spreadsheet and repeated independently by a second reviewer. Consensus was achieved by discussion. Data extraction followed guidelines from the Cochrane Collaboration. Risk of bias was assessed using QUADAS-2. Pooled sensitivity, specificity and diagnostic odds ratios (DORs) were calculated using random effects meta-analysis. Analyses were performed separately for occlusal and proximal lesions. Dentine lesions and cavitated lesions were analysed separately.Results947 articles were identified with the searches and 442 were analysed full text. 117 studies (13,375 teeth, 19,108 surfaces) were included. All studies were published in English. 24 studies were in vivo and 93 studies were in vitro. Risk of bias was found to be low in 23 and high in 94 studies. The pooled sensitivity for detecting any kind of occlusal carious lesions was 0.35 (95% CI : 0.31/40) and 0.41 (0.39/0.44) in clinical and in vitro studies respectively while the pooled specificity was 0.78 (0.73/0.83) and 0.70 (0.76/0.84). For the detection of any kind of proximal lesion the sensitivity in the clinical studies was 0.24 (CI 0.21/0/26) and 0.43 (0.41/0.45) and the specificity was 0.97 (0.95/0.98) and 0.89 (0.88/0.90).With regard to the dentine lesions the sensitivities were 0.36 (0.24-0.49) for proximal to 0.56 (0.53-0.59) for occlusal lesions and specificities ranged between 0.87 (0.85-0.89) and 0.95 (0.94-0.96). No reports were found for cavitated occlusal lesions. For proximal lesions sensitivities were above 0.60 and sensitivities above 0.90. Diagnostic Odds Ratios (DOR) were >1 (indicates a useful test) and were higher in proximal than in occlusal lesions. The DOR calculated for proximal lesions in vitro studies was 16.0 (11.5/22.4) and DOR 7.5 (3.4/16.5) for clinical studies). Heterogeneity calculated using I(2) test was moderate: > 50-67%.ConclusionsCaries detection determined by dental radiographs is highly accurate for proximal lesions and dentine caries lesions. For initial carious lesions the test needs to be used with other more sensitive methods in populations that present with high caries risk.

Early detection of dental caries is critical for timely intervention and prevention of disease progression. The International Caries Detection and Assessment System (ICDAS) offers a standardized approach to evaluate caries through both visual and radiographic methods. Objectives: To compare between visual and radiographic methods using ICDAS criteria in permanent molars for detection of occlusal and proximal caries Methods: This comparative cross-sectional study was conducted at Liaquat University of Medical and Health Sciences (LUMHS) after ethical approval, using non-probability consecutive sampling to recruit 378 patients. Individuals aged 16–35 years with fully erupted, clinically intact permanent molars and no signs of periodontal disease were included. Participants were assigned to Group A (occlusal caries) or Group B (proximal caries), with 189 in each group. Caries were assessed visually and radiographically using ICDAS criteria, with scores 1–2 indicating initial and 3–6 indicating advanced lesions. Two calibrated examiners performed the evaluations. Results: There were no statistically significant differences in baseline demographics between the occlusal and proximal caries groups. The mean age was comparable (25.9 ± 6.5 vs. 26.1 ± 6.2 years, p=0.753), as was gender distribution (p=0.752). When comparing diagnostic methods, no statistically significant differences were observed between visual and radiographic ICDAS assessments for detecting initial or advanced caries in either group (all p>0.05), indicating comparable diagnostic performance. Conclusions: Visual and radiographic methods based on the ICDAS system were equally effective in identifying occlusal and proximal carious lesions in permanent molars.

BackgroundThe early detection of dental caries is crucial for successful dental care. New intraoral scanners using near-infrared irradiation (NIRI) technology track preventive lesions without ionizing radiation. This study aimed to evaluate the performance of intraoral scanners (IOSs) in detecting proximal caries in primary posterior teeth, compared to conventional methods such as loupes-assisted clinical exams and bitewing (BW) radiography.MethodsFifteen examined tooth surfaces were used to produce a total of 60 scores by a restorative dentistry consultant (RDC). The tooth surfaces were categorized into caries-free (n = 5 × 4 exam methods) and carious (n = 10 × 4 exam methods) subgroups. Artificial caries lesions were created on specified surfaces and mounted on typodont in sets for evaluation using a simplified modified ICDAS visual and BW radiographic examination, DIAGNOcam device, and iTero Element 5D NIRI-assisted IOS. Reference surface scores were recorded. Investigators (RDCs and recent dental graduates (RDGs)) were trained and calibrated. Inter-examiner agreement, agreement with reference, specificity, and sensitivity were checked.ResultsThe results showed that the sensitivity and specificity differed between the diagnostic tests. The best agreement of all investigated diagnostic methods with the reference was found using the DIAGNOcam device (ĸ = 0.87) and BW radiography (ĸ = 1.00). High agreement was found for visual examination (by the RDC and RDGs (ĸ ≈ 0.85)) and iTero 5D examination (ĸ = 0.87).ConclusionsThe iTero Element 5D IOS had lower sensitivity and specificity compared to other methods. The potential use of IOSs with NIRI as a substitute for conventional diagnostic methods in primary teeth shows promise but requires further investigation.

Imaging modalities to inform the detection and diagnosis of early caries.

The purpose of this study was to evaluate the accuracy of intraoral scanners in 10 abutments (five premolars and five molars) obtained in a dental clinic and to analyze the impacts of the volume and area of abutments on scanning accuracy. Abutment casts were scanned five times with a 3D contact scanner (DS10; Renishaw plc). The five scan files were lined up and then merged, and one high-resolution computer-aided design reference model (CRM) was obtained. To obtain a computer-aided design test model (CTM), three types of intraoral scanners (CS3600 (Carestream Dental), i500 (Medit), and EZIS PO (DDS)) and one type of laboratory scanner (E1; 3Shape) were employed. Using 3D analysis software (Geomagic control X; 3D Systems), the accuracy of the scanners was evaluated, including optimal overlap by optimal alignment. The conformity of the overlapped data was calculated by the root mean square (RMS) value, using the 3D compare function for evaluation. As for statistical analysis, testing was conducted, using one-way and two-way ANOVA and the Tukey HSD test (α = 0.05) for the comparison of the groups. To analyze the correlations of the volume and area of the abutments with accuracy, Pearson’s correlation analysis was conducted (α = 0.00625). Both premolar and molar abutments showed a lower RMS value on the laboratory scanner than on the intraoral scanners, and the RMS value was lower in premolars than in molars (p < 0.001). In the intraoral scanner group, CS3600 showed the best accuracy (p < 0.001). There were significant positive correlations for the volume and area of the abutments with accuracy (p < 0.001). The type, volume, and area of the clinically applicable abutments may affect the accuracy of intraoral scanners; however, the scanners used in the present study showed a clinically acceptable accuracy range, regardless of the type of abutment.

Radiographic caries detection: A systematic review and meta-analysis

To describe and discuss the benefits and drawbacks of various dental caries diagnostic techniques, including the use of intraoral scanners for caries diagnosis based on near-infrared imaging (NIR) technology. A MEDLINE search from 1980-2023 focused on dental caries diagnostic techniques, emphasizing intraoral scanners using NIR technology. Alternative caries detection methods were also evaluated for their advantages and limitations, enabling a comparison with NIR. The review included traditional caries tools, the latest detection methods, and NIR's role in intraoral scanners, drawing from case reports and both in vivo and in vitro studies. Keywords like "caries detection," "intraoral scanners," and "Near Infrared Imaging (NIRI)" guided the search. After screening titles and abstracts for relevance, full texts with valuable insights were thoroughly analyzed. The data was grouped into three: traditional diagnostics, advanced digital methods, and intraoral scanner-based detection. This comprehensive narrative review described and discussed the current state of dental caries diagnostic methods, given the insufficient number of clinical investigations suitable for a systematic review. Traditional caries diagnosis techniques have shown variable accuracy dependent on a dentist's experience and the potential over-removal of healthy tooth structures. Intraoral scanners have emerged as a novel caries detection method, because of their integration of NIR technology. Various studies have confirmed the efficacy of NIR in detecting interproximal caries and in the early diagnosis of non-cavitated caries. Specifically, intraoral scanners have demonstrated promising results, proving comparable to established diagnostic methods like bitewing radiography. Nevertheless, while the integration of NIR into intraoral scanners seems promising, the technology still faces challenges, notably its accuracy in detecting secondary and subgingival cavities. However, with anticipated integrations of AI, NIR in intraoral scanners could revolutionize early caries detection. Intraoral scanners with NIR technology offer non-destructive imaging, real-time lesion visuals, and enhanced patient communication. Although comparable to bitewing radiography in some studies, a universally accepted diagnostic tool is lacking. Future research should compare them with existing methods, focusing on clinical outcomes, cost-effectiveness, and patient acceptance.

BackgroundThe purpose of this study was to evaluate the accuracy of intraoral scanners by comparing the trueness and precision of several types of scanners in measuring the distance between the ball abutments on pairs of multiple implants.MethodsSeven implants were placed on a fully edentulous upper jaw model. After ball abutments were attached to the implants on the master model, the three-dimensional (3D) shape of the model was evaluated using a computer numerical control 3D coordinate-measuring machine. Subsequently, the 3D shape-related data of the model were obtained using two types of intraoral scanners (3M True Definition Scanner [TDS] and 3Shape Trios3 [TR3]) and two types of laboratory scanners (KaVo ARCTICA Auto Scan [KA] and Identica Hybrid [IH]). Using the obtained 3D shape-related data, the trueness and precision in measuring the distance between the balls within seven pairs of ball abutments were compared among the scanners using 3D analysis software.ResultsIntraoral scanners produced significantly greater errors in trueness and precision than laboratory scanners in measuring the distances between the ball abutments in all the dental regions. Between the intraoral scanners, powder-requiring TDS produced significantly lower errors at inflection points than powder-free TR3.ConclusionsThese results indicate that an optical impression technique using an intraoral scanner is suitable for dental implant treatment in patients with a few missing teeth.

Mosby's comprehensive review of dental hygiene: Edited by Michele Leonardi Darby and Eleanor J. Bushee. Pp. 815. 1986. St Louis, C. V. Mosby. Softback, £22·00

Near-infrared imaging in orthodontic intraoral scanners for early interproximal caries detection

PURPOSEThis study aimed to investigate whether the accuracy of intraoral scanners is influenced by different scanning strategies in an in vitro setting, through a systematic review and meta-analysis.MATERIALS AND METHODSThis review was conducted in accordance with the PRISMA 2020 standard. The following PICOS approach was used: population, tooth impressions; intervention, the use of intraoral scanners with scanning strategies different from the manufacturer’s instructions; control, the use of intraoral scanners following the manufacturers’ requirements; outcome, accuracy of intraoral scanners; type of studies, in vitro. A comprehensive literature search was conducted across various databases including Embase, SciELO, PubMed, Scopus, and Web of Science. The inclusion criteria were based on in vitro studies that reported the accuracy of digital impressions using intraoral scanners. Analysis was performed using Review Manager software (version 5.3.5; Cochrane Collaboration, Copenhagen, Denmark). Global comparisons were made using a standardized mean difference based on random-effect models, with a significance level of α = 0.05.RESULTSThe meta-analysis included 15 articles. Digital impression accuracy significantly improved under dry conditions (P < 0.001). Moreover, trueness and precision were enhanced when artificial landmarks were used (P ≤ 0.02) and when an S-shaped pattern was followed (P ≤ 0.01). However, the type of light used did not have a significant impact on the accuracy of the digital intraoral scanners (P ≥ 0.16).CONCLUSIONThe accuracy of digital intraoral scanners can be enhanced by employing scanning processes using artificial landmarks and digital impressions under dry conditions.

This study aimed to evaluate the accuracy of an intraoral scanner with near-infrared imaging (NIRI) feature in the diagnosis of interproximal caries and to compare it with the visual-tactile method (VTM), bitewing radiography (BWR), and panoramic radiography (PR). Six hundred thirty-nine interproximal surfaces (mesial-distal) of posterior teeth from 22 volunteers were examined. Results were scored by VTM, BWR, PR, and NIRI. Lesions were scored as 0 for no-caries, 1 for early-enamel lesion (EEL), and 2 for lesions involving dentino-enamel junction (DEJ). McNemar, Kappa, and Fleis Kappa tests were used to evaluate the agreement levels. Pearson's Chi-square test was used to determine the matching rates after validation. A good level of agreement was observed between examination methods (Ƙ = 0.613; p < 0.001). In pairwise comparisons, a moderate agreement was seen between all the methods for lesions with DEJ involvement, while a statistically good agreement was observed between BWR and NIRI (Ƙ = 0.675; p < 0.001). As a result of validation, the accuracy of NIRI for molars was considered 85.2% and 75.7% for premolars in EELs, 85.2% for molars, and 70% for premolars regarding the lesions involving DEJ. Intraoral scanners with the NIRI feature may be used for diagnosing interproximal caries, especially for permanent molars. Early detection of proximal caries is one of the most essential topics forming the basis of preventive dentistry. This study investigates a caries diagnostic tool integrated into intraoral scanners to diagnose interproximal caries. A caries diagnostic tool integrated into an intraoral scanner may prevent the harmful effects of ionizing radiation in early caries diagnosis and may improve the patient's oral health status.

Radiographic methods have poor sensitivity for occlusal lesions and by the time the lesions are radiolucent they have typically progressed deep into the dentin. New more sensitive imaging methods are needed to detect occlusal lesions. In this study, cross-polarization optical coherence tomography (CP-OCT) and near-IR imaging were used to image questionable occlusal lesions (QOC's) that were not visible on radiographs but had been scheduled for restoration on 30 test subjects. Near-IR reflectance and transillumination probes incorporating a high definition InGaAs camera and near-IR broadband light sources were used to acquire images of the lesions before restoration. The reflectance probe utilized cross-polarization and operated at wavelengths from 1,500 to 1,700 nm where there is an increase in water absorption for higher contrast. The transillumination probe was operated at 1,300 nm where the transparency of enamel is highest. Tomographic images (6 × 6 × 7 mm3 ) of the lesions were acquired using a high-speed swept-source CP-OCT system operating at 1,300 nm before and after removal of the suspected lesion. Near-IR reflectance imaging at 1,500-1,700 nm yielded significantly higher contrast (P < 0.05) of the demineralization in the occlusal grooves compared with visible reflectance imaging. Stains in the occlusal grooves greatly reduced the lesion contrast in the visible range yielding negative values. Only half of the 26 lesions analyzed showed the characteristic surface demineralization and increased reflectivity below the dentinal-enamel junction (DEJ) in 3D OCT images indicative of penetration of the lesion into the dentin. This study demonstrates that near-IR imaging methods have great potential for improving the early diagnosis of occlusal lesions. Lasers Surg. Med. 49:215-224, 2017. © 2017 Wiley Periodicals, Inc.

PURPOSEThe present study aimed to evaluate the accuracy of a desktop scanner and intraoral scanners based on the volumetric dimensions of a complete arch.MATERIALS AND METHODSSeven reference models were fabricated based on the volumetric dimensions of complete arch (70%, 80%, 90%, 100%, 110%, 120%, and 130%). The reference models were digitized using an industrial scanner (Solutionix C500; MEDIT) for the fabrication of a computer-aided design (CAD) reference model (CRM). The reference models were digitized using three intraoral scanners (CS3600, Trios3, and i500) and one desktop scanner (E1) to fabricate a CAD test model (CTM). CRM and CTM were then superimposed using inspection software, and 3D analysis was conducted. For statistical analysis, one-way analysis of variance was used to verify the difference in accuracy based on the volumetric dimensions of the complete arch and the accuracy based on the scanners, and the differences among the groups were analyzed using the Tukey HSD test as a post-hoc test (α=.05).RESULTSThe three different scanners showed a significant difference in accuracy based on the volumetric dimensions of the complete arch (P<.05), but the desktop scanner did not show a significant difference in accuracy based on the volumetric dimensions of the complete arch (P=.808).CONCLUSIONThe accuracy of the intraoral scanners was dependent on the volumetric dimensions of the complete arch, but the volumetric dimensions of the complete arch had no effect on the accuracy of the desktop scanner. Additionally, depending on the type of intraoral scanners, the accuracy differed according to the volumetric dimensions of the complete arch.

(1) Background: The purpose of this study is to evaluate the full arch scan accuracy (precision and trueness) of nine digital intra-oral scanners and four lab scanners. Previous studies have compared the accuracy of some intra-oral scanners, but as this is a field of quickly developing technologies, a more up-to-date study was needed to assess the capabilities of currently available models. (2) Methods: The present in vitro study compared nine different intra-oral scanners (Omnicam 4.6; Omnicam 5.1; Primescan; CS 3600; Trios 3; Trios 4; Runyes; i500; and DL206) as well as four lab light scanners (Einscan SE; 300e; E2; and Ineos X5) to investigate the accuracy of each scanner by examining the overall trueness and precision. Ten aligned and cut scans from each of the intra-oral and lab scanners in the in vitro study were brought into CloudCompare. A comparison was made with the master STL using the CloudCompare 3D analysis best-fit algorithm. The results were recorded along with individual standard deviation and a colorimetric map of the deviation across the surface of the STL mesh; a comparison was made to the master STL, quantified at specific points. (3) Results: In the present study, the Primescan had the best overall trueness (17.3 ± 4.9), followed by (in order of increasing deviation) the Trios 4 (20.8 ± 6.2), i500 (25.2 ± 7.3), CS3600 (26.9 ± 15.9), Trios 3 (27.7 ± 6.8), Runyes (47.2 ± 5.4), Omnicam 5.1 (55.1 ± 9.5), Omnicam 4.6 (57.5 ± 3.2), and Launca DL206 (58.5 ± 22.0). Regarding the lab light scanners, the Ineos X5 had the best overall trueness with (0.0 ± 1.9), followed by (in order of increasing deviation) the 3Shape E2 (3.6 ± 2.2), Up3D 300E (12.8 ± 2.7), and Einscan SE (14.9 ± 9.5). (4) Conclusions: This study confirms that all current generations of intra-oral digital scanners can capture a reliable, reproducible full arch scan in dentate patients. Out of the intra-oral scanners tested, no scanner produced results significantly similar in trueness to the Ineos X5. However, the Primescan was the only one to be statistically of a similar level of trueness to the 3Shape E2 lab scanner. All scanners in the study had mean trueness of under 60-micron deviation. While this study can compare the scanning accuracy of this sample in a dentate arch, the scanning of a fully edentulous arch is more challenging. The accuracy of these scanners in edentulous cases should be examined in further studies.