Background/Objectives: Multilayer zirconia restorations can feature a shade gradient or a strength gradient, with layers differing in color or phase composition within the same material. The aim of this in vitro study was to evaluate the color stability in all layers of multilayer zirconia after exposure to staining solutions and artificial aging. Methods: Square-shaped specimens (N = 120) of color A2 were fabricated from 4Y-PSZ and 3Y/4Y-PSZ multilayer zirconia—Katana STML, DD Cube One ML, and Katana YML—and their baseline color values (T0) were measured with a clinical spectrophotometer (VITA Easyshade V). The specimens were randomly divided into four groups (n = 10/gp) and immersed in physiologic solution, 0.2% chlorhexidine gluconate (CHX) mouth rinse, and staining coffee solution. Then, they were measured continuously for 7 (T1), 14 (T2), and 21 days (T3). The last group of specimens underwent accelerated aging in a steam autoclave at 134 °C and 2 bar pressure and measured after 1 (T1), 3 (T2), and 5 h (T3). After the immersion process and artificial aging, discoloration values (ΔE) were calculated using the formula ΔE = [(ΔL*)² + (Δa*)² + (Δb*)²]^1/2 and analyzed with the SPSS v 23.0 software with a p value < 0.05. Results: All specimens showed significant color differences in the T3 measurements after exposure to coffee and CHX, with the highest ΔE values in the enamel layers. Katana YML showed the most significant differences in ΔE in the cervical layers after exposure to artificial aging. Conclusions: Multilayer zirconia exhibited dependent optical changes, with the enamel layers being the most affected after exposure to staining solutions. Gradient pigmentation and differences in phase composition caused differences in color to the multilayer zirconia layers after exposure to staining solutions and artificial aging.

Background/Objectives: Diabetes mellitus is associated with significant health complications, including challenges in periodontal health. Gingival inflammation is especially common among diabetic patients and can significantly impact overall diabetes management. This study aims to investigate the correlation between glycosylated hemoglobin (HbA1c) levels, an established marker of glycemic control, and gingival inflammation using the Quantitative Gingival Bleeding Index (QGBI) among hospitalized diabetic patients, thereby placing the question within a broader clinical context. Methods: The study enrolled 671 hospitalized patients with diabetes complications at “Mother Theresa University Hospital” in Tirana, AL, USA. Glycemic control was assessed through glycosylated hemoglobin (HbA1c) levels, and gingival health was evaluated using the Quantitative Gingival Bleeding Index (QGBI). Behavioral variables were also documented, including smoking habits and routine oral care practices. Spearman’s correlation coefficient (r_s) was applied to determine the relationship between HbA1c levels and QGBI scores. Results: Our findings revealed a strong positive correlation between glycemic control (HbA1c) and gingival inflammation (QGBI) among the participants (Spearman’s coefficient r_s = 0.868, p < 0.001). Additionally, significant positive associations were observed between behavioral factors, such as smoking habits and regular oral care practices, further underscoring their role in periodontal health in diabetic patients. Conclusions: The study highlights a significant positive relationship between poor glycemic control and increased gingival inflammation, emphasizing the importance of periodontal health in the comprehensive management of diabetes mellitus. Our results support integrating periodontal evaluation and management into standard diabetes care, which could improve patient outcomes and overall well-being.

Background As the prevalence of systemic co-morbidities and polypharmacy increases among dental patients, the risk of clinically significant drug-drug interactions (DDIs) has become a critical concern in outpatient care. In this narrative review, we evaluated the pharmacological risks associated with the most common dental prescriptions, including analgesics, antimicrobials, and local anesthetics, in patients with underlying systemic conditions under long-term treatment. Materials and methods A comprehensive literature search was conducted across PubMed, Scopus, and Google Scholar using MeSH terms related to “dental drug interactions”, “pharmacovigilance in dentistry”, and “adverse drug reactions”. We synthesized data from clinical trials, systematic reviews, and pharmacological guidelines published over the last 16 years. Results Analysis revealed that common dental therapeutics are not always “low-risk” interventions. Interactions can range from decreased treatment efficacy to potential severe complications. Furthermore, the review highlights the lower levels of pharmacovigilance and Adverse Drug Reaction reporting among dental professionals. Conclusions The findings underscore significant “underlying risks” in routine dental practice. To ensure patient safety, dental practitioners must shift toward an evidence-based prescribing model that prioritizes pharmacological literacy, systematic pharmacovigilance, and proactive reporting of Adverse Drug Reactions (ADRs).