BACKGROUND: To evaluate the effect of staining beverages on the color-changing of resin-infiltrated artificial white spot lesions (WSLs).
METHODS: Thirty-five artificial WSLs were created by pH cycling on flat bovine teeth specimens. The WSLs were treated with resin infiltration and were divided into five groups based on staining beverages: artificial saliva, coffee, wine, green tea, and Coca-Cola. These specimens were subjected to a 28-day exposure to the respective beverages. Color stability was assessed using a spectrophotometer at different time points: baseline, after 7, 14, 21, and 28 days of exposure, and repolishing. The color difference (∆E) between each time point and the baseline was calculated. Statistical analysis was performed using two-way measures ANOVA with a significance level of p = 0.05.
RESULTS: All resin-infiltrated specimens exposed to staining beverages for 7 days exhibited more significant color changes than those exposed to artificial saliva. The color change patterns varied based on the type of beverage. The color alterations intensified with extended immersion in the wine and Coca-Cola groups, while there were no significant differences in the color of specimens after 28 days of immersion in the coffee and green tea groups. However, after cleaning with pumice powder, all specimens showed significantly reduced color changes compared to those observed after 28 days of immersion, except those immersed in coffee.
CONCLUSIONS: Exposure of resin-infiltrated bovine tooth specimens to staining beverages resulted in a significant color alteration as the immersion time increased. However, the staining effect could be minimized by cleaning with pumice powder, except for the coffee group.
CONCLUSIONS: After resin infiltration treatment, patients should be advised to minimize the consumption of colored beverages to prevent staining that could impact esthetic appearance.

The second paper in this two-part review series aims to outline the long-term complications of dental trauma in the adult patient in relation to discoloured, displaced or missing teeth. A brief overview of the cause of discolouration is outlined, followed by assessment and management options. These can include bleaching, veneers, or crown restorations to mask the discolouration. Displacement of teeth from the socket can occur due to luxation injuries. Management can include simple digital manipulation, surgical repositioning, or orthodontic extrusion based on the severity of extrusion and the time from injury. Teeth can be lost early or in the long-term following dental trauma and associated hard and soft tissues deficiencies may also ensue. Replacement options can include a removable partial prosthesis, resin-retained bridge or dental implants. Often, hard and soft tissue augmentation procedures may be required to address any defects and rebuild lost anatomical contours. A thorough assessment followed by the development of a sound management plan which takes patients\' general and local factors into account can ensure a predictable and successful treatment outcome. This would end in an aesthetically pleasing and a functionally stable result for the patient.

Black stain (BS) and caries are common oral issues in children worldwide. This study aimed to reveal the prevalence of BS and caries in primary dentition of children in Qingdao, China and evaluate the potential association between them. A total of 672 preschool children aged 3-5 years old from 12 kindergartens in Qingdao, northern China were enrolled in the study. The prevalences of BS and caries were counted, and their distributions across different ages and genders were analyzed. The potential protective role of BS (independent variable) on caries (dependent variable) was analyzed via binary logistic regression analysis. BS was observed in 103 children (15.33%), including 3 severe- (0.45%), 28 moderate- (4.17%), and 72 mild (10.71%) forms. Caries was observed in 374 children (55.65%) and it was positively associated with age. Notably, the prevalence of caries was lower in children with BS than in those without BS (42.72% vs. 58.00%, respectively). Children with BS were less likely to suffer from caries than those without BS. BS in mild or moderate/severe forms was associated with a low risk of caries. In summary, the prevalence of BS in primary dentition in Qingdao, China is at a relatively high level worldwide. BS is a protective factor for caries in primary dentition.

BACKGROUND: Regenerative endodontics involves the use of various root canal medicaments and scaffolds, which may cause crown discoloration.
OBJECTIVE: This study aimed to investigate the combined crown discoloration of scaffolds [platelet-rich fibrin (PRF) and blood clot] applied after administration of different medicaments [modified triple antibiotic paste including doxycycline (mTAPd), modified double antibiotic paste (mDAP), calcium hydroxide (CH), and propolis].
METHODS: In total, 100 human mandibular premolar teeth were selected and prepared. The teeth were apically resected to simulate immature teeth. The positive and negative control groups (n = 10) consisted solely of blood-only and serum-only samples. The remaining 80 teeth were used for the experimental groups with four different medicaments. Three weeks later, either blood or PRF was applied as a scaffold after removing the medicaments (n = 10). Color changes were assessed before medication placement and at the end of the first, second, and third weeks, as well as on days 0, 1, 30, 60, and 90 after scaffold application. Analysis was carried out using repeated measures of variance, Friedman, one-way ANOVA, Kruskal-Wallis, the dependent paired t-test, and Wilcoxon test.
RESULTS: Statistical significance was determined at P = 0.05. All groups including blood and the group including propolis and PRF combination, resulted in a significant increase in discoloration (P < 0.05) and discoloration exceeding clinically acceptable thresholds.
CONCLUSIONS: CH and the modified versions of TAP (mTAPd) and DAP (mDAP) demonstrated an acceptable level of discoloration when used with a combination of PRF at day 90.

BACKGROUND: Silver diamine fluoride (SDF) is becoming more widely recognized as a simple, cost-effective approach to minimize sensitivity and arrest caries. However, SDF results in caries that are stained black. Potassium iodide (KI) treatment with SDF may minimize or lessen the staining. However, the effectiveness of KI on staining has not been investigated. Studies demonstrating that potassium iodide reduces the black staining are still insufficient. This paper presents the study protocol for Healthy Smiles, a randomized controlled trial implemented to compare the staining propensity of SDF and SDF+KI.
OBJECTIVE: This study, Healthy Smiles, aims to evaluate the staining propensity of SDF and SDF+KI using a Nix Mini color sensor among children aged 4 to 6 years. Another objective of the study is to evaluate the caries-arresting effect of SDF and SDF+KI in the treatment of carious primary teeth.
METHODS: This study is a randomized controlled trial. A total of 60 children with caries that meet the criteria of the International Caries Detection and Assessment System (code 1 or above) will be randomly assigned to treatment groups, where group 1 will be treated with SDF and group 2 will be treated with SDF+KI. Discoloration of treated lesions will be assessed digitally using a Nix Mini color sensor. Participants will be followed up at 1, 3, and 6 months after treatment to digitally record the ∆L and ∆E values using the Nix Mini color sensor. Data will be analyzed using SPSS (version 28; IBM Corp). Independent sample t tests and the Mann-Whitney U test will be used to compare the 2 groups.
RESULTS: Enrollment started in October 2023. It is estimated that the enrollment period will be 12 months. Data collection is planned to be completed in 2024.
CONCLUSIONS: The presented paper describes Happy Smiles, a project that provides an opportunity to address the aesthetic inconvenience of patients without compromising the effectiveness of the SDF treatment. The trial findings will contribute to the limited evidence base related to discoloration after SDF intervention to improve aesthetic appearances in child oral health. If the results from the trial are promising, it will lead to the development of a model for child oral health and pave the way for further research in child oral health.
UNASSIGNED: PRR1-10.2196/51087.

OBJECTIVE: This study aims to compare and evaluate the changes in color caused by four different biomaterials utilized as intracanal coronal barriers in the regenerative endodontic procedure at varying intervals of time.
METHODS: A total of 100 extracted mandibular single-rooted premolars were taken. Samples were standardized, and access cavity preparation was done. All the canals were instrumented and irrigated thoroughly. They were divided into five groups: A, B, C, D, and E (n=20), i.e., the control group, gray mineral trioxide aggregate (MTA), white MTA, Biodentine, and calcium hydroxide. Each group was further subdivided into two subgroups (n=10), where one subgroup was prepared with normal saline and the other was prepared with platelet-rich fibrin (PRF). Digital photographs were taken at baseline, immediately after the placement of biomaterials, after 72 hours, seven days, and six months, using a DSLR camera. The color evaluation was done using the Adobe Photoshop 2021 software using the CIE L*a*b color system. The data obtained were recorded and statistically analyzed using IBM SPSS Statistics for Windows, Version 23 (Released 2015; IBM Corp., Armonk, New York). Continuous variables were analyzed using a one-way ANOVA test and post-hoc analysis. The P-value was set to be significant at <0.05.
RESULTS: Statistically significant variation was obtained in all four experimental groups regarding change in color (ΔE) over periods of 72 hours, seven days, and six months. At six months, all the experimental groups presented with a perceptible color variation (ΔE>3.3).
CONCLUSIONS: The color change was significant after six months in all groups. Biodentine produced the least color alteration, whereas gray MTA produced the highest.

OBJECTIVE: To explore the efficacy of iRoot BP plus in the treatment of adult carious pulp exposure and its impact on pulp blood flow.
METHODS: A total of 126 cases of 156 permanent teeth from adult patients with carious pulp exposure who were treated from January 2020 to January 2022 were selected, the patients were divided into experimental group(63 cases with 79 permanent teeth) and control group(63 cases with 77 permanent teeth) by the envelope method. The experimental group was treated with iRoot BP plus, while the control group was treated with mineral trioxide polymer. The differences in treatment effectiveness, operation time, and tooth discoloration between the two groups were observed. Statistical analysis was performed with SPSS 22.0 software package.
RESULTS: There was no significant difference in treatment success rates between the experimental group and the control group at 3, 6, and 12 months after surgery(P＞0.05). The operating time for each capsule in the experimental group was (2.53±0.41) min, which was significantly shorter than that in the control group(P＜0.05). The incidence of tooth discoloration in the experimental group at 12 months after surgery was 3.80%, which was significantly lower than that in the control group (P＜0.05). The bite force quotient and masticatory efficiency of the experimental group 12 months after operation were (16.65±1.14) Ibs and (94.45±5.65)%, which were significantly higher than those of the control group(P＜0.05).
CONCLUSIONS: IRoot BP plus has good efficacy in the treatment of adult carious pulp exposure, with advantages such as convenient operation, less tooth discoloration, less inflammatory reactions and stable pulp blood flow after decline.

OBJECTIVE: to investigate whether baseline mineral distribution modulates the ability of silver diammine fluoride (SDF) to remineralize and stain enamel caries lesions.
METHODS: This laboratory study followed a 3 [treatment: SDF/fluoride varnish (FV)/deionized water (DIW)] ×3 [lesion protocol: methylcellulose (MeC)/hydroxyethylcellulose (HEC)/Carbopol 907 (C907)] factorial design. Lesions were created in bovine enamel specimens (n = 20). Treatments were applied and lesions remineralized in artificial saliva. Digital transverse microradiography (TMR-D) was used to analyze lesions. Lesion color was monitored spectrophotometrically. The effects of lesion protocol and treatment on changes in lesion depth (ΔLD), mineral loss (ΔΔZ), maximum mineral density at the surface zone (ΔSZmax), and color changes related to remineralization (ΔL*remin) were analyzed using two-way ANOVA.
RESULTS: The treatment×lesion protocol interaction was significant for ΔΔZ (p < 0.01) and ΔL*remin (p < 0.01), however not for ΔLD (p = 0.23) or ΔSZmax (p = 0.91). There were no differences in ΔΔZ between treatments in HEC and C907 lesions. However, DIW resulted in more remineralization than both SDF (p < 0.01) and FV (p = 0.01) in MeC lesions. Considering changes from lesion baseline after remineralization in MeC lesions, SDF treatment resulted in the highest mineral gain in the surface zone. However, DIW revealed the highest mineral gain after remineralization in the lesion body. SDF stained lesions with the intensity increasing after remineralization in C907 lesions, whereas staining decreased in MeC and HEC lesions.
CONCLUSIONS: High fluoride treatments can interfere with continuous remineralization of caries lesions due to partial arrest. Baseline lesion mineral distribution affects SDF\'s ability to enhance remineralization and the staining caused by SDF.
CONCLUSIONS: SDF is being used to arrest active caries lesions extending into dentin and to treat dentin hypersensitivity. This study shed light on SDF\'s effect on an isolated process in dental caries only, remineralization. It achieved this by examining enamel caries lesions with differing mineral distributions and assessing their staining properties.

BACKGROUND: The black staining effect of silver-containing solutions for use to arrest caries can have a negative aesthetic impact on children and parents. This study aims to assess the staining effects of Silver Diamine Fluoride/Potassium Iodide (SDF/KI), SDF and Nanosilver Fluoride (NSF).
METHODS: Forty-four extracted carious primary molars were collected and randomly divided into four groups (n = 11). The carious tissue in all teeth was removed using a chemo-mechanical caries removal agent with an excavator. After caries removal in all groups, SDF, SDF/KI, and NSF were applied to the different groups, while no solution was applied to the control group. Subsequently, the teeth in all groups were restored with compomer. Color values L*, a* and b* were measured using a spectrophotometer at three time points: immediately after compomer restoration (T0), one week later (T1), and four week later (T2). Changes in brightness (ΔL) and color (ΔE) over time were calculated and comparisons among groups were made.
RESULTS: The SDF solution induced statistically significant black staining (p = 0.013) and a decrease in L* value (p < 0.001) on the compomer material compared to the other groups over time.
CONCLUSIONS: It was observed that SDF/KI has the potential to reduce the black staining effect of SDF, though not entirely. Novel experimental solutions like NSF may offer an alternative to counteract the staining effect of SDF.

The objective of this work is to report a restorative approach with composite resin applied in reverse in the aesthetic resolution of darkened anterior teeth. A 27-year-old female patient presented with the main complaint of dissatisfaction with the aesthetics of her smile due to dental darkening, a result of childhood trauma, without painful symptoms, pathological clinical signs or change in care. In the intraoral examination, a darkening of teeth 11 and 21 was observed, which radiographically showed thickening of the periodontal ligament, with disharmonious configuration of the marginal gingiva. From the clinical and radiographic characteristics, we opted for periodontal intervention for recovery and gingival levelling, followed by endodontic intervention and aesthetic restorative restoration. The restorative step was carried out sequentially by internal tooth bleaching, removal of dentin still pigmented after bleaching and enamel preservation. Soon after, it was restored in an alternative way and layered using a technique called reverse, using strips of polyethylene fiber over the dentin resin. The technique preserved the remaining enamel with the maintenance of the original remaining guides, proving to be a viable conservative alternative since of the diagnosis to the restorative conclusion in view of the longitudinal confirmation of the restorative efficacy after 1 year.