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Background: One of the drawbacks of tooth-colored dental restorations is their discoloration over time. The present study aimed to determine the effect of four categories of pediatric medications, including analgesics, antibiotics, anticonvulsants, and multivitamins, on two types of tooth-colored dental materials, namely, composite resins and glass ionomer cements. Materials and Methods: In this in vitro study, a total of 40 specimens with disc shapes (with a diameter of 5 mm and thickness of 2 mm) were prepared from each material and immersed in eight different drugs for 2 min three times a day for 1 week. The values of the baseline color were calculated based on the CIE (International Commission on Illumination) L*a*b* system. After 7 days, ΔE values were calculated. Two-way analysis of variance was employed for statistical analysis. Statistical significance was defined at 0.05. Results: Statistical analysis showed that there were significant differences between ΔE and different restorative materials as well as ΔE and drug types (P < 0.001). Conclusion: According to the results of this in vitro study, all the four types of drugs caused the discoloration in all the restorative materials, and the color change values were affected by the type of used drug and restorative material.

Background. The effect of keratinized tissue width on the peri-implant health has not been well elucidated. The results of previous studies on this topic are controversial and the role of keratinized tissue width in the long-term success of dental implants has not been confirmed. This cross-sectional study aimed to assess the correlation of keratinized tissue width with periodontal indices around implant-supported fixed partial dentures (FPDs). Methods. This cross-sectional study evaluated 73 implants. Patients underwent periodontal examinations, including measurement of plaque index (PI), gingival index (GI), clinical probing depth (PD), bleeding on probing (BOP), marginal gingival recession, keratinized mucosa width and radiographic marginal bone level. Data were analyzed using SPSS. Results. The mean GI, PI and marginal gingival recession around implants with <2 mm width of keratinized gingiva were greater than the corresponding values around implants with keratinized tissue width of ≥2 mm. However, this difference was not statistically significant (P>0.05). No significant differences were noted in PD and radiographic marginal bone level between the two implant groups with keratinized tissue width <2 mm and ≥2 mm. Thus, no correlation was found between the keratinized tissue width and the measured indices. Conclusion. Although this study did not show a significant correlation between the keratinized tissue width and peri-implant tissue health and consequently the implant success rate, long-term interventional studies are required to make a final judgment in this respect.