Influence of filling materials on the fracture resistance of resin composite used for sealing screw access hole

Abstract

Introduction Screw-retained restorations have a screw access hole (SAH) sealed with resin composite aiming at safe-guarding the aesthetic features of the ceramic veneer. The loss or wear of the resin composite applied in sealing the SAH is among the most common complications in implant prosthodontics, as the fracture of ceramic veneer. Objective Evaluate the influence of sealant materials on the fracture resistance of resin composite applied in sealing screw access hole in screwed (SAH) implants. Material and method The samples were produced from UCLA abutments in metallic NiCr alloy with subsequent application of ceramic. After asperisation and conditioning ceramic surface, was applied silane and dentin adhesive, before sealing the conduits with resin composites Z100 and P60. Nine groups (n=10) were evaluated: sealing with Z-100 (ZNC) and P-60 (PNC) without obturation of SAH; sealing with Z100 (ZCP) and P-60 (PCP) with absorbent cotton; Z100 (ZPT) and P60 (PPT) with polytetrafluoroethylene; Z100 (ZGP) and P60 (PGP) with gutta-percha and a cemented ceramic crown (ICS). After the fracture resistance test, the data were analyzed using two-way ANOVA and Tukey HSD tests (p<.05). Result The fracture mode was evaluated by scanning electron microscope. Irrespective of the filling material, the highest mean values of fracture resistance were observed in the sealing with P60 (p=.002). When combined with resins composed of a sealing material, the results obtained were: ZGP: 805.5N/ PGP: 929.5N<ZPT: 1079.1N/ PPT: 1149.5N=ZNC 1183.1N/ PNC: 1350.6N<ZCP: 1403.6N/ PCP: 1641.3N<ICS: 2645.0N. Conclusion The use of P60 with cotton wool exhibited the highest fracture resistance.

Water Absorption Behavior of Dual-Sponge Structure Sealing Elastomers Assisted by Machine Learning

“…The resulting product was washed with anhydrous ethanol and dried for 12 h, yielding an AA/AM/ACM composite super absorbent polymer (C-SAP). 10 2.3. Preparation of C-SAP@NaHCO 3 /FKM Composite.…”

“…Once the dripping was complete, the mixture was kept at a constant temperature for 1 h. Then, the temperature was raised to 70 °C, and the stirring rate was increased for 3 h. During this period, pore-forming agents including 3.5 g of sodium bicarbonate and 5 mL of acetone were added. The resulting product was washed with anhydrous ethanol and dried for 12 h, yielding an AA/AM/ACM composite super absorbent polymer (C-SAP) …”

“…By adding water-absorbent resin, the polar nature of FKM enhances its interactions with both water-absorbent resin and water molecules, surpassing those of other common elastomers such as PU and NR. 10 Furthermore, FKM, as a material with two-stage vulcanization characteristics, can better preserve its mechanical strength unaffected by the water-absorbent resin. 11,12 Currently, common super absorbent polymer (SAP) have the drawback of having a high water absorption rate but poor water retention performance, 13,14 making them prone to leaching.…”

“…With an inherent strength exceeding 10 MPa, it can meet the requirements of the vast majority of applications. By adding water-absorbent resin, the polar nature of FKM enhances its interactions with both water-absorbent resin and water molecules, surpassing those of other common elastomers such as PU and NR . Furthermore, FKM, as a material with two-stage vulcanization characteristics, can better preserve its mechanical strength unaffected by the water-absorbent resin. , …”