Surface Microhardness of Microhybrid and Nanocomposite After Storage in Mouth Washes

Abstract

Background: Dental composites are aesthetic direct restorative material. However, the effect of mouthwashes on the durability of the material is controversial. This study evaluated and compared the influence of mouthwash composition on the surface hardness of nanofilled (Z350XT) and microhybrid (P60) resin composites. Methods: Comparative in-vitro study was conducted over 6 months at Multan Medical & Dental College. Sixty-four disc-shape specimens of each {nanofilled (Z350XT) and microhybrid (P60)} resin composite were prepared and stored in distilled water at 37°C for 24 hours. The baseline microhardness reading (To) was recorded by Vickers micro-hardness tester. Samples were then randomly divided into four groups (n=16) and stored in Listerine Cool Mint, Colgate Plax, Clinica and distilled water (control). The hardness test was repeated after 12 hours and 24 hours of storage. Results: Nanocomposite (Z350XT) had statistically (p<0.01) higher surface hardness. A significant reduction (p≤0.05) in microhardness was observed after immersion of samples in mouthwashes. The reduction in surface hardness was dependent on the immersion time and composition of mouthwashes. Listerine Cool Mint (alcohol-based mouthwash) had greatest degradation effect. Conclusion: Mouth rinses negatively impacted the surface microhardness of the tested resin-based materials. Alcohol-based mouthwashes had greater potential for reducing microhardness. Microhybrid composite appears to be a more suitable material for restoring teeth in patients accustomed to using regular mouthwashes.

Role of Follicle-stimulating Hormone, Inhibin B, and Anti-Müllerian Hormone in Predicting Sperm Retrieval from Men with Nonobstructive Azoospermia Undergoing Microdissection Testicular Sperm Extraction: A Systematic Review and Meta-analysis

“…The role of AMH in adult males is not completely understood, but it is believed to correlate with spermatogenesis. As for InhB, AMH may be considered as a marker of Sertoli cell maturation, whereby more immature cells produce more AMH than less immature cells, possibly reflecting the degree of spermatogenesis [21] , [33] , [34] , [35] , [36] . This led to the hypothesis that AMH levels could predict SR at mTESE.…”

Mouthwashes: Surface Hardness and Accuracy of Dual-cured Visible Light-Cured Composite

“…Following many studies, the hardness of some types of the composite was found highly affected by using Listerine mouthwash. This softening effect was found to directly adhere to the alcohol percentage (25,27,28) . On the other hand, in a study by Spuldaro et.…”

“…Several studies suggested that Listerine as one of the commonly used mouthwashes may adversely affect the hardness of composite resin. This may relate to the high alcohol-content percentage of either ethanol or methanol (12,25) . Material hardness is related directly to its strength and rigidity, and the clinical durability may be implicated due to chemical softening resulting from the use of some mouthwashes (26) .…”

Comparação da microdureza da resina composta com a técnica de índice convencional e modificada com moldeira impressa em dois tempos de fotopolimerização

“…En diversos estudios sobre la microdureza de las resinas compuestas polimerizadas, se hace referencia a que en la cara superior de la resina se encontró mayor microdureza que en la cara inferior, variando según la distancia a la que se coloque la unidad emisora de luz que le permitirá fotopolimerizar (19)(20)(21)(22)(23)(24)(25). Al ser así, las resinas son resistentes a las cargas y a la abrasión, y aumenta sus valores mientras más próxima se encuentre la fuente emisora de luz a la resina, siendo esto positivo (25)(26)(27)(28)(29)(30)(31)(32).…”