Background and Aim: The appearance of teeth plays a key role in human social interactions. TOOTH DISCOLORATION is one of the most frequent causes for patients to visit the dentist. TOOTH DISCOLORATION is usually aesthetically unpleasant for patients and has a negative psychological effect on them. Orthodontic treatment, despite its well-known benefits, is a risk factor for TOOTH DISCOLORATION, ranging from imperceptible changes and loss of transparency to white and brown spot lesions. The current review study investigates the etiology of TOOTH DISCOLORATION after fixed orthodontic treatment and also describes its different treatment options. Material and Method: In this review study, articles published in reputable databases, including PubMed/Medline, Scopus, and Web of Science, were reviewed without time limits until 2024. The articles were searched using the keywords Teeth DISCOLORATION and fixed orthodontics. Initially, 153 articles were reviewed, of which 31 were excluded due to similarity and 96 were excluded due to inconsistency with the topic. The abstracts of other articles were reviewed, and finally, 14 articles were included in the study. Conclusion: TOOTH DISCOLORATION after orthodontic treatment is multifactorial, and various etiological factors can directly or indirectly contribute to its development. The debonding process, type of adhesive system, finishing and polishing techniques, and type of brackets used are all factors that contribute to DISCOLORATION. Dentists must first diagnose the cause of the DISCOLORATION, educate the patient about its cause, and adopt appropriate management techniques.

Objectives The present experimental study aimed to assess the in vitro effect of sodium bicarbonate (SB) on TOOTH discolouration. Methods Forty-five extracted anterior teeth were decoronated 2 mm apical to the cementoenamel junction. The crowns were immersed in tea solution for 7. 5 days. The teeth were divided into three groups (n = 15 per group) on a random basis. The groups were exposed to either SB paste 94%, hydrogen peroxide (HP) 40%, or carbamide peroxide (CP) 45%. Then, teeth were bleached according to the manufacturers' instructions. Next, all TOOTH samples were immersed again in tea solution for 10 min. The CIE L*a*b* colour parameters of the teeth were evaluated at baseline (T1), after primary staining (T2), after bleaching (T3), and after re-staining (T4) using a spectrophotometer. The enamel surface morphology of one sample from each group was evaluated pre-and post-bleaching using scanning electron microscopy (SEM). Within-group and between-group comparisons were made using repeated measures ANOVA and Tukey’s test. Results 94% of cases had color change(∆E) more than 3. 5 with no enamel surface wear after Applying SB. HP showed a maximum bleaching effect of ∆E = 8. 77. After re-staining, the SB group showed minimal staining (∆E = 3. 77) compared to the HP and CP groups. Conclusion The present findings show that SB can chemically resolve TOOTH discolouration and prevent re-staining. Considering its low abrasiveness, optimal safety, low cost, antimicrobial activity, and availability, it seems to be ideal for use at home.

Introduction: A desirable quality of any endodontic sealer is its ability to be TOOTH color friendly. Therefore the aim of the present study was to evaluate the TOOTH DISCOLORATION potential of a nano zinc oxide-eugenol (NZOE) sealer. Methods and Materials: In order to evaluate TOOTH DISCOLORATION, the pulp chamber of 60 human maxillary central and lateral incisors were filled with one of the sealers, naming AH-26 (resin-based sealer), Pulpdent sealer (ZOE-based) and a NZOE experimental sealer. Color measurements was assessed at the baseline (before placement of sealers) (T0), 24 h (T1) and 72 h (T2) h, 1-week (T3), and 1-month (T4) after the placement of sealers using the Easy Shade spectrophotometer. Data were analyzed in SPSS software using one-way ANOVA, and repeated measured ANOVA. Results: No significant differences were observed when the paired comparison test was performed (P>0. 05). Conclusion: The tested NZOE sealer had similar TOOTH DISCOLORATION potential in comparison with AH-26 and ZOE sealer.

Objective: Selection of an appropriate shade of composite is critical in achieving an esthetic restoration. Different systems are used to assess and describe color parameters. This study aimed to assess the effect of color and thickness of Filtek Supreme (FS) and Premise (P) composite resins on correction of TOOTH DISCOLORATION.Methods: In this in vitro experimental study, 10 anterior teeth with Vita A2 color shade were selected. Composite specimens were fabricated in 0.5 and 0.75 mm thicknesses of FS and P composites. Intact teeth, prepared teeth, prepared teeth with enamel and dentin composite discs on their buccal surfaces, stained teeth and stained teeth with composite discs were photographed using a digital camera under standard conditions and color change (DE) at different phases was calculated.Results: The L*, a* and b* color parameters in prepared and unstained teeth were not significantly different from those of intact teeth. In stained teeth, the L* parameter only in prepared and stained teeth with 0.75mm P composite was not significantly different from the L* parameter in intact teeth. Significant differences were seen in other stained teeth. The a* and b* parameters only in prepared and stained teeth with 0.5 mm FS composite were significantly different from those in intact teeth. By increasing the thickness of composite, the color change in comparison with intact teeth decreased in both groups.Conclusion: The results showed that the effect of type of composite, its thickness and their interaction on the color change was significant when using FS and P composites in 0.5 and 0.75mm thicknesses in comparison to intact teeth and the lowest color difference with intact teeth was achieved using 0.75mm thickness of P composite (enamel and dentin).

Objectives: This study aimed to investigate the impact of three different bleaching protocols on TOOTH DISCOLORATION caused by tea. Materials and Methods: Forty extracted sound premolars were cleaned, disinfected, and their initial color parameters were measured (T1). The teeth were then immersed in boiled tea solution for 24 hours, and their color was measured again (T2). The samples were divided into four groups of 10 teeth each. Group A was treated with an in-office bleaching gel followed by 30 seconds of light curing. Groups B, C, and D were respectively treated with 0. 24M oxalic acid followed by bleaching gel, 5. 25% sodium hypochlorite followed by bleaching gel, and a combination of 0. 24M oxalic acid, 5. 25% sodium hypochlorite, and bleaching gel. The color was measured once more after the interventions (T3). Data were analyzed using two-way repeated measures ANOVA, paired sample t-test, and Tukey's test. Results: The mean color change (∆E2) between T2 and T3 was significantly higher in group D compared to group A (P<0. 05). However, there was no significant difference in color change between groups A, B, and C. Additionally, there was no significant difference in color change between groups B, C, and D. The groups also showed significant differences in ∆L (P=0. 007), with the only significant difference found between groups B and C (P=0. 001). Conclusion: The combined use of sodium hypochlorite and oxalic acid followed by in-office bleaching gel is more effective than bleaching alone in correcting TOOTH DISCOLORATION caused by tea. This protocol can further reduce yellow coloration.

Statement of the Problem: The endodontically treated teeth usually suffer from the DISCOLORATION induced by endodontic materials, which can adversely affect the esthetical outcome of a treatment. Purpose: This study aimed to compare the DISCOLORATION caused by the silver nano-particles coated with imidazolium as an irrigant, sodium hypochlorite (NaOCl), and chlorhexidine gluconate (CHX). Materials and Method: The root tips of 65 single-rooted human teeth were resect-ed and root canal systems were chemomechanically prepared from the apical as-pect. The specimens were randomly divided into three experimental (n=15) and two control groups (n=10). In the experimental groups, the substance was placed in the root canal for 30 minutes, and then washed with normal saline. Saline or blood alone was used in the control groups. The DISCOLORATION was assessed spectropho-tometrically right after substance placement (T1), 1 week (T2), and 1 (T3) and 3 months (T4) after and color change values were calculated. Statistical analysis was performed using multi-sample repeated measures analysis of variance, Tukey's HSD, and Sidak tests. Results: In T1, there was no significant difference in color change between silver nano particle, blood and CHX (p> 0. 05); but these three groups had significantly more Δ E value than NaOCl and Normal Saline (p< 0. 05). NaOCl and normal saline had no significant difference in T1 (p> 0. 05). In T2, T3 and T4 results were the same and showed blood and silver nano particle had significantly higher color change in comparison with NaOCl, CHX and normal saline (p< 0. 05). There was no significant difference between NaOCl, CHX, and normal saline in TOOTH discol-oration (p> 0. 05). There was no significant difference between silver nano particle and blood in ability of TOOTH DISCOLORATION (p> 0. 05). Conclusion: Within the limitation of this study, silver nano particle material could not be suggested as an intra-canal irrigant regarding its unfavourable TOOTH discol-oration.

Introduction: There are numerous factors that can lead to TOOTH DISCOLORATION after endodontic treatment, such as penetration of endodontic materials into the dentinal tubules during root canal treatment. The aim of thisin vitro study was to compare DISCOLORATION induced by TOOTH colored mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement in extracted human teeth.Methods and Materials: Thirty two dentin-enamel cuboid blocks (7×7×2 mm) were prepared from extracted maxillary central incisors. Standardized cavities were prepared in the middle of each cube, leaving 1 mm of enamel and dentin on the labial surface. The specimens were randomly divided into two study groups (n=12) and two positive and negative control groups (n=4). In either study groups the cavities were filled with MTA or CEM cement.The positive and negative control groups were filled with blood or left empty, respectively. The cavities were sealed with composite resin and stored in normal saline. Color measurement was carried out by spectrophotometry at different time intervals including before (T0), and 1 week (T1), 1 month (T2) and 6 months (T3) after placement of materials. Repeated-measures ANOVA was used to compare the DISCOLORATION between the groups; the material type was considered as the inter-subject factor. The level of significance was set at 0.05.Results: No significant differences were detected between the groups in all time intervals (P>0.05).Conclusion: TOOTH DISCOLORATION was similarly detectable with both of the two experimental materials.