Tooth Shade Research Articles

The influence of tooth shade on near-infrared light transmission through human dentine and enamel: an in-vitro study

This in-vitro study assessed the influence of the shade of human teeth on the transmission of near-infrared light. A total of 40 teeth were used. After cleaning the root surface and removing cementum, the teeth were sectioned into slices 3 mm thick, with each comprising a portion of the crown (enamel-dentine (ED)) and of the root (dentine only). The shade of the crown and the root was measured using a digital spectrophotometer. All samples were irradiated using 660, 808, or 904 nm diode lasers, and a multi-wavelength LED light source (700–1100 nm, Nuralyte®). Using a laser power meter, the percent transmission was calculated. Differences between Vita shade groups A, B, and C were analysed using ANOVA and post-hoc tests. Overall, dentine samples showed approximately 40% greater transmission than samples of enamel and dentine. There were significant influences for shade group and for sample thickness on the transmission of 660 nm light (P < 0.01), but not for other light sources. There was a statistically significant influence of light source on transmission. Across both crown and root samples, the ranking for light transmission from greatest to least was LED (700–1100 nm) > (904 nm = 808 nm) > 660 nm. Within the range from 660 to 1100 nm, the longer wavelengths are transmitted better by both enamel and dentine. The transmission of visible red light (660 nm) was affected by Vita tooth shade, while the transmission of near infrared light (700–1100 nm) was not affected by Vita shade.

Accuracy and Reliability of Intraoral Scanners for Tooth Shade Determination in Comparisons with Intraoral Spectrophotometer: In Vitro Study

Abstract Objective This study aimed to compare the accuracy and repeatability of shade determination using an intraoral spectrophotometer (SP) and two intraoral scanners, hypothesizing no significant differences in performance. Materials and Methods A computer-aided design/computer-aided manufacturing-designed right upper central incisor was manufactured in multiple shades using feldspathic ceramic. Shade determination was performed using the CEREC Primescan (CP), Trios V scanners, and an intraoral SP, with multiple scans taken for each. Statistical Analysis Measurement accuracy was evaluated using the Cochran Q test and pairwise comparisons with Bonferroni's correction. Reliability was assessed through Cronbach's α, with a significance level set at 0.05 for all tests. Results The SP achieved 84% accuracy, while the CP and 3Shape Trios V (T5) recorded 66 and 71%, respectively. None of the instruments reached 100% accuracy, with the SP displaying an accuracy range of 80 to 90%, and both scanners achieving between 60 and 80%. Statistically significant differences indicated that the SP outperformed the scanners (p &lt; 0.05). False shade readings showed shades 3M2 and 4M2 as having the highest erroneous results. Reliability scores ranged from 92% for the scanners to 94% for the SP, with a Cronbach's α coefficient of 0.839, indicating high reliability. Conclusion Intraoral SP displayed superior accuracy over the intraoral scanners, while their reliability in shade assessment was comparable. Thus, dental SPs are preferred for precise shade matching, suggesting potential reliability issues with intraoral scanners for consistent dental shade assessment.

ML-based tooth shade assessment to prevent metamerism in different clinic lights

The aesthetic understanding has found its place in dental clinics and prosthetic dental treatment. Determining the appropriate prosthetic tooth color between the clinician, patient and technician is a difficult process due to metamerism. Metamerism, known as the different perception of the color of an object under different light sources, is caused by the lighting differences between the laboratory and the dental clinic. The traditional trial-error color determination method, coupled with the high cost of instrumental color value determination, has prompted the need for alternative technologies. The integration of AI technologies into dental practices aims to minimize errors in tooth shade assessment, reduce equipment usage, eliminate the impact of clinic lighting on color detection, and decrease costs for patients, dentists, and laboratories. In this study, a machine learning (ML) based approach that can correctly detect tooth shade even under different clinical lights has been developed. A dataset consisting of 580 dental images taken under four different clinical lights and with five repetitions was created using the Vita color shade guide. Experimental studies were performed using the HSV color space, 6 different ML algorithms and color histograms. As a result, 97.93% accuracy rate was achieved by using cross-validation (cv = 5) in the classification of 29 color values ​​independent of clinical lights. It has been shown that the tooth colors can be determined with high accuracy using ML algorithms and metamerism can be prevented.

A Randomized Clinical Study Investigating the Stain Removal Efficacy of Two Experimental Dentifrices.

This study aims to evaluate extrinsic tooth stain removal and whitening efficacy of two experimental dentifrices containing (i) 5% sodium tripolyphosphate (STP)/1% micronized alumina or (ii) 5% STP/1% micronized alumina with abrasive silica (ED2) compared to a regular fluoride dentifrice (RFD) following 8 weeks of use. This was a single-center, randomized, controlled, blind, three-arm, stratified, parallel-group study. Eligible participants underwent clinical assessment of stain on the facial/lingual surfaces of maxillary and mandibular teeth using the modified Lobene stain index (MLSI), and shade of the facial surfaces of the central and lateral maxillary incisors using the VITA Bleachedguide 3D-Master (VITA) shade guide. Participants brushed twice daily with their assigned dentifrice and returned to the clinic for clinical assessments at weeks 4 and 8. A total of 272 participants completed the study (281 screened, 279 randomized). Both experimental dentifrices demonstrated statistically significant reduction from baseline and significant differences compared to RFD for MLSI and VITA shade scores at 4 and 8 weeks. 10 treatment-related treatment-emergent adverse events were reported in seven participants. All were resolved at the end of the study. This study demonstrated that dentifrices containing 5% STP/1% micronized alumina provide enhanced stain removal and shade improvements compared to a regular dentifrice. Study treatments were generally well tolerated. A low-abrasion daily-use fluoride dentifrice containing 1% micronized alumina and 5% STP, suitable for people at risk of erosive toothwear and/or dentin hypersensitivity, can provide clinically meaningful superior reductions in tooth stain, which translates into a visibly noticeable improvement in tooth shade.

ASSESSMENT OF TEETH COLOR BEFORE AND AFTER THE BLEACHING PROCEDURE USING DIGITAL VISUALIZATION

Dyscoloration of teeth hard tissues is a fairly common problem among the population of our country. Therefore, different methods of teeth whitening treatment are highly popular in the field of modern aesthetic dentistry. Due to a high demand of teeth whitening procedure, there is a great interest in researching the issue of color at dentistry. The main goal. Comparative assessment of tooth color (in vitro) using digital image before and after procedure with a help of a hydrogen peroxide-based whitening system. Materials and methods. The study was conducted on permanent teeth that were removed for orthodontic indications at patients aged from 18 to 39 years. Comparison of effectiveness color change after bleaching procedure was conducted on two halves of teeth divided in a half. The separation was carried out in the longitudinal direction along the axis of the tooth. Teeth whitening was performed according to the following steps: professional dental hygiene/Air Flow/application of the “Beyond” 35% H2O2 whitening gel/12 min, activation with blue light/3 times/remineralization therapy. Results. Comparing digital images of teeth before and after whitening with the “Beyond” system and E according to the CIELAB color space between the colors of two tooth parts we indicate from 22 to 40 units, E 34,0±5,9. The quality of whitening is mostly pronounced at patients with an average degree of staining, in which the tooth shade corresponds to shades from C2 to B3 according to the reorganized VITA scale. Conclusions. The usage of color science at dentistry, combined with instrumental methods of measuring tooth color, allows us for qualitative and accurate determination of shade and whiteness. Our patients experience rapid and safe improvement of tooth color after whitening with the Beyond system, according to the CIE L*a*b* system, E between the colors of two tooth particles is from 22 to 40 units, on average 34.0±5.9 units.

Influence of background color and target tooth shade on shade-matching accuracy

Aim: This study analysed the effect of background color and target tooth shade on visual shade-matching. Materials and Method: Twenty prosthodontists performed visual shade-matching on four different backgrounds (green, grey, white, black) using the Vita Classical shade guide. Two identical shade guides were used for shade-matching. One of them was blinded so that the color codes on it could not be identified. Each observer matched all 16 shade tabs using the second shade guide on four different backgrounds. The effects of background and target tooth shade factors on shade-matching accuracy were analyzed with the Chi-square test. A two-proportion z-test with Bonferroni correction was applied to pairwise comparisons. P

Simplified Composite Restorations for Fractured Young Incisors: A Clinical Review.

Tooth fractures are a common consequence of dental trauma in young patients, requiring prompt and effective restorative interventions that ensure both functional integrity and esthetic appeal. Although resin stratification (layering) is the gold standard for achieving life-like restoration of fractured teeth, many clinicians find it technically challenging due to the time and effort required for precise shade matching, concealing the fracture line, and accurate placement of resin composite layers with different levels of opacity. The more recent generation of monoshade composites, with their ability to adapt to various tooth shades, reduce the complexity of multi-layer restorations, and improve chairside efficiency. Additionally, the composite cutback technique has gained attention as an effective method for restoring fractured teeth in young patients. This method combines the benefits of monoshade composites and the precision of simple additional layering to enhance both the esthetic and functional outcomes of the restorations. This mini-review provides a comprehensive analysis of the composite cutback technique, the role of monoshade composites, and their clinical application in the restoration of fractured young teeth.

Exploring the influence of tooth, ceramic, and resin luting agent variations on laminate veneer optical characteristics: a prospective clinical investigation.

This study evaluated the influence of tooth shade, resin-based luting agent shade values, and ceramic thickness on the optical properties of CLVs. The study involved 16 participants who received 95 CLVs. CIE L*, a*, b* color coordinates were assessed with a clinical spectrophotometer. Variables considered were: luting agent value in three levels (high, medium, low); tooth shade before and after preparation in two levels (lighter and darker shades); and CLV thickness in two levels (< 1mm, ≥ 1mm). The color difference (ΔE00) was analyzed under four scenarios, utilizing statistical methods suitable for non-normal distributions. Ninety-five CLVs (n = 95) were analyzed, ceramic thicknesses mean (SD) values were 0.70 (± 0.15) for < 1mm group and 1.19 (0.20) for ≥ 1mm group. ΔE00 values ranging from 2.93 to 9.72, all exceeding the thresholds of perceptibility and acceptability. Significant variations were observed in optical outcomes based on the clinical variables studied, particularly showing that high-value luting agents are more effective over darker substrates (p = 0.043). Thicker ceramics significantly improved masking capabilities, demonstrating their critical role in esthetic treatments (p = 0.024). No significant differences were found regarding the tooth shade after preparation (p = 0.215). The study confirmed that luting agent shade values and ceramic thickness, critically influence the final optical properties of CLVs. High-value luting agents and thicker ceramics effectively achieved acceptable color differences, especially over darker tooth substrates. These findings underscore the importance of carefully selecting materials and techniques to optimize optical outcomes in CLV restorations. Luting agent's value and ceramic thickness plays a critical role in achieving natural-looking ceramic laminate veneers, especially on darker tooth substrates. These factors significantly impact the final color matching and esthetic outcome.

A Comparative Study of Tooth Shade Selection Methods Between Visual, Smartphone Camera, and Vita Easyshade Spectrophotometer.

Recently, dental esthetics have increasingly emphasized appearance, with tooth shade selection complicated by the enamel and dentin's translucency and opacity. Smartphone cameras are useful for shade matching. Currently, no study has directly compared the accuracy of this method. Therefore, the aim of this study is to compare the accuracy of the visual method, smartphone photography, and the Vita Easyshade spectrophotometer, particularly for chroma, value, and hue. This cross-sectional study involved a convenient sample of 82 dental students from the College of Dental Medicine at Umm Al-Qura University, including those in their 5th, 6th, and 7th(intern) years. The VITA classical shade guide was utilized to compare three methods of shade selection: the conventional visual method, smartphone photography, and the Vita Easyshade spectrophotometer. The percentage accuracy for each method was calculated with a 95% confidence interval (CI), using the visual method as the reference standard. Statistical comparisons of the shade selection methods, as well as gender differences, were performed using a Chi-Square test. Fisher's exact test was applied where expected cell counts were below five. Stata software was used with a significance threshold of 0.05. The current study included 82 subjects; 42 were females and 40 were males. There was no significant difference between male and female students in the measured accuracy by using the three methods except for hue when the photo method was used (p=0.015). For chroma (p=0.094), value (p=0.965), and hue (p=0.094), the photo method was comparable in accuracy to the visual method. The accuracy was slightly higher for the photo method, but this difference was not statistically significant. The Easyshade was also comparable to the visual method in chroma (p=0.674), significantly lower when assessing value (p=0.002) and not statistically lower when assessing hue (p=0.094). Comparing the results of the same method, the accuracy of shade selection was highest for chroma, followed by value, and lowest for hue. Within the limitations of this study, digital photography using a smartphone camera may serve as a reliable method for cliniciansin shade selection during clinical practice.

Comparison of tooth shade determination using two methods: visual and spectrophotometric

Introduction: Dental color determination is a crucial procedure in oral rehabilitation treatments, since with precision, aesthetically correct results will be achieved that fit the naturalness of the patient's teeth. Thanks to technological advances, new tools have emerged, such as spectrophotometers, intraoral scanners, among others, which have significantly improved the way of carrying out this process.Objective: To evaluate the effectiveness of dental color determination with the visual method compared to the spectrophotometer.Methods: A descriptive and documentary study was carried out following a systematic bibliographic search of articles in the last 10 years, which were selected according to the inclusion and exclusion criteria.Results: The study compared the effectiveness of two methods to determine the color of teeth: visual and instrumental (with a spectrophotometer). The visual method, although traditional, presents high variability due to factors such as lighting, the observer's experience and the individual perception of color. The spectrophotometer offers a more objective and reproducible measurement of color, as it is not influenced by external factors. Although both methods can achieve similar results in some cases, significant differences were generally observed in the selection of the dental shade. The spectrophotometer allows for the detection of more subtle color differences and offers greater consistency in the results.Conclusion: Dental shade measurement is more effective with a spectrophotometer, however, the authors recommend using the two methodologies together.

Comparison of the Clinical Evaluation of Digital Tooth Shade Determination Using an Intraoral Scanner with Proven Subjective and Objective Methods.

Background/Objectives: Despite the increasing use of chromatic intraoral scanners, color determination is often performed visually, offering poor reliability and validity. In this study, we aimed to compare the reliability and validity of the tooth shade determination tool of an intraoral scanner (Trios3 Color) with that of two dental spectrophotometers (VITA Easyshade Advance 4.0 and SpectroShade Micro) and with visual determination using the VITA 3D-Master shade guide. Methods: In vivo tooth shade determination was performed on 33 participants using positioning splints for the right central incisor. Repeated measurements assessed the reliability in determining the percentage agreement with VITA 3D-Master shades. VITA Easyshade measurements were used as reference values for validity. The metric value Delta E (ΔE) in the International Commission on Illumination L*a*b* color space was compared to the reference, with ΔE greater than 1 indicating visible differences and a maximum value of ΔE 6.8 being clinically acceptable. Results: The reliabilities of VITA Easyshade, the intraoral scanner, and SpectroShade Micro were 75.8%, 87.9%, and 89.9%, respectively. The visual method had an agreement rate of 20.6%. Validity values, compared with the reference value, were ΔE 3.8 (clinically acceptable), 8.3, and 7.4 (the latter two both being clinically unacceptable) for the intraoral scanner, area-measuring device, and visual method, respectively. Conclusions: The intraoral scanner is a reliable and valid tool for tooth shade determination and is superior to the visual method in both aspects.

Bleaching Gels and Light-Emitting Diodes: Comparison of Tooth Color Change.

To measure difference in tooth shade and color achieved via two different over-the-counter bleaching agents with and without their associated light-emitting diodes (LEDs). A total of 84 extracted human anterior teeth were randomly divided into seven groups. Gypsum models were made with 6 extracted teeth in an arch form (n = 12; 2 arches/group). Samples were kept hydrated throughout treatment (25°C). Bleaching treatment followed manufacturers' instructions with at least 1-h of rehydration between treatments. Control tooth arches were left untreated. L*a*b* values were measured with a Vita Easyshade (VITA North America, Yorba Linda, CA) three times per tooth using white and black backgrounds. ∆E (CIE 2000) was compared between and within treatment groups over time with ANOVA and post hoc Tukey (a = 0.05). Subgroup testing confirmed the data were normally distributed. Two-way ANOVA showed significant interaction between product (Control, Crest, Snow) and treatment (light only, product only, light and product) on ∆E values for black (p-value < 0.001, F = 15.28) and white (p-value < 0.001, F = 13.62) backgrounds. Post hoc pairwise Tukey tests showed a significant effect of light-and-product treatments in contrast to light- or product-only treatments. Repeated measures ANOVA of between-treatment change (∆E) by product showed significant interaction between time and treatment for Snow products (p < 0.001, F = 10.9) and independent effects of time and treatment for Crest products (Time: p-value < 0.001, Treatment: p-value < 0.01, F = 7.21) on a black background. On white backgrounds, only a significant effect of treatment was reported for both Snow (p-value < 0.01, F = 5.427) and Crest (p-value < 0.001, F = 5.61). Overall, a combination of light and gel produces significantly higher tooth color and shade change over time, with the highest change seen for Snow products. Many patients use over-the-counter tooth bleaching products because they are more cost effective and easier to access than in-office bleaching. However, these products may have adverse effects, such as increased sensitivity with repeated use, in addition to increased consumption of time and money. This project measured tooth shade between treatments which can help determine which product is most effective for at home use.

The relationship of tooth shade and skin tone and its influence on smile attractiveness in native South Indians: A web-based cross sectional survey

ObjectivesThis study aimed to investigate the influence of tooth shade and skin tone on smile attractiveness among native South Indians. The primary research question was whether there is a significant relationship between these variables and perceived smile attractiveness. Materials and methodsA web-based cross-sectional survey was conducted with approval from the Institutional Review Board of (Thai Moogambigai Dental College and Hospital, Chennai). Standardized smile photographs of two South Indian models (one male and one female) were digitally modified to display four different tooth shades and four different skin tones, resulting in 32 images. These images were incorporated into a Google Form along with a questionnaire and a Visual Analog Scale (VAS) for attractiveness rating. The survey was distributed to 1200 participants, including both dental professionals and the general population, with 1000 valid responses recorded. Statistical analysis was performed using IBM SPSS Statistics, employing parametric tests to evaluate the data. ResultsThe study found that lighter tooth shades were consistently rated higher in attractiveness for both genders. Lighter tooth shades such as FS1T1 and FS2T1 scored means of 6.88 and 7.27 respectively for females, while darker shades like FS1T4 scored lower with a mean of 4.95. Similarly, males showed a preference for lighter tooth shades with MS1T1 and MS2T1 scoring means of 5.57 and 5.78 respectively compared to darker shades like MS1T4 with a mean of 3.63. Significant differences were noted across age groups and genders, with younger participants and females showing a stronger preference for lighter tooth shades. ConclusionsThe study concludes that both tooth shade and skin tone significantly influence smile attractiveness, with a clear preference for lighter tooth shades among the surveyed population. These findings suggest the importance of considering these factors in aesthetic dental treatments to enhance patient satisfaction and achieve optimal results. Clinical relevanceThe results underscore the necessity for dental practitioners to take into account both tooth shade and skin tone when planning aesthetic dental treatments. This approach will help in achieving a more harmonious and natural appearance, ultimately improving patient satisfaction with the treatment outcomes. Future research should continue to explore the cultural and individual factors that contribute to these preferences in dental aesthetics.

Impact of different lighting conditions on the tooth-shade selection using intra-oral scanners: An in-vitro study

ObjectivesTo evaluate the accuracy in tooth shade selection under various lighting conditions using different devices, including a color spectrophotometer (CSP) and two intra-oral scanners (IOS: IOS-1 and IOS-2). MethodsTooth shade measurements were performed on a standardized shade guide (16 shades, A1-D4) using CSP, IOS-1 and IOS-2. These evaluations were carried out under three lighting conditions: (1) DL - device light source only, (2) RL - DL plus room light, and (3) CL - RL plus dental-chair light. Each shade was measured ten times per lighting condition with each device by a single investigator. Shade detection accuracy was defined as the percentage of matches to the known shade. Logistic regression models were used for statistical analyses (α = 0.05). ResultsA total of 1440 measurements were conducted. Lighting conditions of increasing intensity significantly decreased the shade detection accuracy of the devices (CSP: RLvsDL, p > 0.9999, Odds Ratio (OR) = 1; CLvsDL, p = 0.0726, OR = 0.6053, IOS-1: RLvsDL, p < 0.0001, OR = 0.2862; CLvsDL, p < 0.0001, OR = 0.05239 and IOS-2: RLvsDL, p = 0.0002, OR = 0.376; CLvsDL, p < 0.0001, OR = 0.1908). CSP, IOS-1, and IOS-2 had shade detection accuracies of 43.75 %, 74.38 %, and 59.38 % respectively under DL. In RL, IOS-1 and IOS-2 dropped to 50.63 % and 40.63 %, respectively; CSP remained unchanged. Under CL, the accuracy dropped for all devices (CSP: 35.63 %, IOS-1: 20.63 %, IOS-2: 28.75 %). Additionally, the devices demonstrated higher accuracy when measuring shade A compared to shades B, C, and D. ConclusionsThe findings of this in vitro study concluded that the accuracy of tooth shade detection was more reliable, particularly for individuals with shade A, when spectrophotometers and intraoral scanners were used with only their built-in light source. Further purpose-built clinical studies are required to confirm these findings in a clinical context.

A Clinical Comparison Between New and Conventional Methods for Quantification of Intended and Fabricated Dental Porcelain Color

Introduction: The accurate selection of dental porcelain shades is crucial for achieving natural-looking and aesthetically pleasing restorations. This study aimed to compare the effectiveness of various shade selection methods, including visual assessment, spectrophotometry, and intraoral scanning. Aims and Objectives: This study aims to improve the accuracy of shade selection in prosthodontics. To achieve this, it will compare digital, intraoral, and visual methods, identify factors influencing shade selection, develop educational guidelines for dentists, and minimize color discrepancies between chosen and final shades. Methods: A diverse group of 37 participants with 111 shades of teeth were involved. Three shade selection methods were employed: visual assessment using a shade guide, spectrophotometry with the VITA Easyshade Compact, and intraoral scanning with the Medit i700. The accuracy of each method was determined by comparing the selected shade to the fabricated porcelain restoration. Results: While digital methods (spectrophotometry and intraoral scanning) simplified the shade selection process, visual assessment, especially when performed by experienced dentists, consistently demonstrated higher accuracy. Factors such as lighting conditions and individual variations in color perception influenced the reliability of visual assessment. Discussion: The study emphasizes the importance of a comprehensive approach to shade selection, combining both visual and digital methods. Digital tools offer objective measurements, while visual assessment captures subtle nuances in color and ensures patient satisfaction. Conclusion: The optimal shade selection method depends on the specific clinical situation and the dentist's expertise. By incorporating both visual and digital techniques, dental professionals can enhance the accuracy and reliability of shade selection, ultimately leading to more natural-looking and aesthetically pleasing dental restorations.

Prevalence, satisfaction and preference of tooth shades and their correlation with age, gender and skin shade: A cross sectional study

Shade selection is one of the most important factors that determines the satisfaction of the patient with the dental prosthesis and thus the overall success of the treatment. Conventional methods of shade selection require the presence of existing teeth or past dental/photographic records. In the absence of these, shade selection becomes challenging and must be done subjectively and arbitrarily based on the patient’s age and sex. This study aims to assess the prevalence, satisfaction, and preference of tooth shades, investigating their correlation with age, sex, and skin shade in a diverse sample of 120 participants. Methods A total of 120 participants, evenly distributed among 60 males and 60 females, were surveyed. Participants were categorized into age groups (n=15) and asked about their satisfaction with existing tooth shades and their preferences. Results The most common existing tooth shade was Value 2 (52.5%). Statistical analysis using Chi-square tests revealed that Value 2 was the most desired shade among males and females alike, particularly in the age group of 41 to 50 years (p &lt; 0.001). Shade 2L1.5 was the most prevalent (n=26), with Value 2 (59.16%) being the most sought-after shade, followed by Shade 2L1.5 (n=21), Shade 2M1 (n=18), Shade 1M1 (n=15), and Shade 2R1.5 (n=14). Existing tooth shades of Value 0 were the least common. The highest satisfaction with existing shades was observed in males aged 41 to 50 (n=15), followed by males aged 51 to 60 (n=14) and females aged 31 to 40 (n=12) and 41 to 50 (n=12). Significant differences in satisfaction were noted among males (p &lt; 0.001). Conclusions This study reveals a consistent and strong preference among both males and females for tooth shades classified as Value 2, following the VITA Tooth-Guide 3D Master shade guide. This universal preference suggests the relevance and acceptance of this shade category across diverse patient groups.

Color Comparison Between Intraoral Scanner and Spectrophotometer Shade Matching: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis compared the accuracy of intraoral scanners and spectrophotometers in determining tooth shade. An electronic search of five databases (PubMed, Scopus, Embase, Web of Science, CENTRAL) was conducted on October 19, 2023. A total of 163 studies were identified from the databases, of which 23 articles were eligible for inclusion. In vivo and in vitro quasi-experimental studies were included. After data extraction, a quantitative analysis was performed to determine the accuracy of the intraoral scanner in subgroups using four outcomes: trueness and precision with different measurement locations. A random-effects model was used to pool effect sizes. The pooled proportion with a 95% confidence interval (CI) was used for the effect size measure. Eleven articles were included in the meta-analysis. Trueness with the intraoral scanner was between 0.28 (CI: 0.09-0.60) and 0.38 (CI: 0.24-0.53). Repeatability was between 0.81 (CI: 0.64-0.91) and 0.85 (CI: 0.74-0.92). Trueness showed low, and precision had moderate certainty of evidence. The trueness of shade matching with intraoral scanners is low compared to spectrophotometers, although the precision is considered high and is similar to spectrophotometers. Shade determination with intraoral scanners is not recommended.

Comparative Evaluation of Impact of In-office Bleaching Agents on Shade and Gloss of Permanent Teeth -An In-vitro Study

Comparative Evaluation of Impact of In-office Bleaching Agents on Shade and Gloss of Permanent Teeth -An In-vitro Study

Comparing Skin Tones to Shades of Upper Anterior Teeth: An Observational Study among Nigerian Adults.

Skin tones may be predictive of anterior tooth shade. An analysis of the relationship of skin tone to anterior tooth shade within a population may facilitate the prescription of complete dentures with optimal esthetics and realism. This study aimed to assess the relationship between skin tones and shades of upper anterior teeth among a diverse Nigerian adult population. The study was conducted between February and December 2022 among consecutive healthy adults recruited from dental clinics of five teaching hospitals in four cities located across four geopolitical zones of Nigeria. Skin tones were recorded using the National Immigration Service (NIS) Skin Color scale. The Vitapan Classic® shade guide was used to record the tooth shade of the upper central incisors and canines. Bivariate and multivariate tests of associations were performed, and predictive probabilities were developed. A total of 1070 adults with a mean age of 30.8 ± 10 years participated in the study. NIS skin tones 6 (29.8%) and 5 (27.7%) were the most common, while hues A (48.7% in incisors and 48.4 % in canines) and B (41.1% in incisors and 40.1% in canines) were predominant. The values of the incisors and canines were positively related to skin tone (P = 0.001) and age (P = 0.001 for incisors and P = 0.003 for canines). Hue was also significantly associated with skin tone for canines (P = 0.01) and gender (P = 0.001). Regression models showed increasingly darker skin tones were positively related to duller values for incisor teeth (β = 0.173, OR =1.19, P < 0.001). The values for canines were more likely to be >2 (β = 0.118, OR =1.12, P = 0.01), but without significant positive relationship to increasingly darker skin tones (β = -0.99, OR =0.91, P = 0.22). Skin tones were associated with upper anterior tooth shade. There was a positive relationship between skin tones and the shades of upper anterior teeth. Skin tones could guide the clinician in shade selection during complete denture prescriptions.

Perception of dental appearance and aesthetic analysis among patients, laypersons and dentists.

Current concepts of beauty are increasingly subjective, influenced by the viewpoints of others. The aim of the study was to evaluate divergences in the perception of dental appearance and smile esthetics among patients, laypersons and dental practitioners. The study goals were to evaluate the influence of age, sex, education and dental specialty on the participants' judgment and to identify the values of different esthetic criteria. Patients sample included 50 patients who responded to a dental appearance questionnaire (DAQ). Two frontal photographs were taken, one during a smile and one with retracted lips. Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from (0-10), where 0 represent (absolutely unaesthetic) and 10 represent (absolutely aesthetic). One-way analysis of variance (ANOVA) and t-test analysis were measured for each group. Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance. Among laypersons (including 488 participants), 47 pictures "with lips" out of 50 had higher mean aesthetic scores compared to pictures "without lips". Among the dentist sample, 90 dentists' perception towards the esthetic smile and dental appearance for photos "with lips" and "without lips" were the same for 23 out of 50 patients. Perception of smile aesthetics differed between patients, laypersons and dentists. Several factors can contribute to shape the perception of smile aesthetic. To compare the perception of dental aesthetic among patients, laypersons, and professional dentists, to evaluate the impact of age, sex, educational background, and income on the judgments made by laypersons, to assess the variations in experience, specialty, age, and sex on professional dentists' judgment, and to evaluate the role of lips, skin shade and tooth shade in different participants' judgments. Patients sample included 50 patients who responded to DAQ. Two frontal photographs were taken: one during a smile and one with retracted lips. Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from (0-10), where 0 represent (absolutely unaesthetic) and 10 represent (absolutely aesthetic). One-way ANOVA and t-test analysis were measured for each group. Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance. Among laypersons (including 488 participants), 47 pictures "with lips" out of 50 had higher mean aesthetic scores compared to pictures "without lips". Whereas among the dentist sample, 90 dentists' perception towards the esthetic smile and dental appearance for photos "with lips" and "without lips" were the same for 23 out of 50 patients. Perception of smile aesthetics differed between patients, laypersons and dentists. Several factors can contribute to shape the perception of smile aesthetic.