Taymour Noha, Hussein Abdel Kader Sanaa, Aboushelib Moustafa N, Gad Mohammed M
Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia.
Department of Conservative Dentistry, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
Saudi Dent J. 2024 Apr;36(4):603-609. doi: 10.1016/j.sdentj.2024.01.016. Epub 2024 Feb 4.
Impressions that maintain their dimensional stability after autoclaving effectively control cross-infection and contamination resulting from a patient's oral secretions.
The study aimed to assess the dimensional stability of autoclavable polyvinyl siloxanes after disinfection and sterilization.
A stainless steel metal model containing three full veneer crown preparations was fabricated according to ANSI/ADA specification No. 19. Reference grooves were established on the occlusal and axial surfaces of the abutments for accurate measurements. Forty impressions were created from the master model using single-step impression technique monophase polyvinyl siloxane material (AFFINIS, Coltene/Whaledent, Altstatten, Switzerland). The impressions were categorized into four groups: Group A (control, ten untreated impressions), Group B (ten disinfected impressions with 5.25 % sodium hypochlorite [NaOCl]), Group C (ten disinfected impressions with 2 % glutaraldehyde), and Group D (ten autoclaved impressions at 134 °C for 18 min). Subsequently, stone casts were produced using type IV gypsum products (Gelstone , BK Giulini Chemie, Ludwigshafen/Rh., Germany). The dimensional accuracy of the obtained casts was assessed by measuring the inter-abutment measurements (between the abutments) and the intra-abutment measurements (diameter and height of the abutments). These measurements were performed using a universal measuring microscope (Olympus stereomicroscope B061 Imaging Corp. Tokyo, Japan) with a precision of 0.001 mm. The dimensions of the stone casts from the study groups were then compared to those of the control group. Data analysis was performed using a one-way ANOVA with a significance level of α = 0.05.
AFFINIS impressions subjected to chemical disinfection in 5.25 % NaOCl and 2 % glutaraldehyde with different immersion times showed slight expansion in the intra- and inter-abutment measurements. The impressions autoclaved at 134 °C for 18 min showed slight shrinkage in the intra- and inter-abutment measurements. The dimensional change was statistically non-significant, and the percent of dimensional changes within the experimental groups was within the clinically accepted limit (α < 0.5).
AFFINIS polyvinyl siloxanes retain dimensional stability suitable for clinical use when subjected to chemical disinfection and steam autoclaving.
在高压灭菌后仍能保持尺寸稳定性的印模能有效控制患者口腔分泌物导致的交叉感染和污染。
本研究旨在评估可高压灭菌的聚乙烯基硅氧烷在消毒和灭菌后的尺寸稳定性。
根据美国国家标准学会/美国牙科协会第19号规范制作一个包含三个全冠预备体的不锈钢金属模型。在基牙的咬合面和轴面上设置参考凹槽以进行精确测量。使用单步印模技术和单相聚乙烯基硅氧烷材料（AFFINIS，库尔齿科/维他登，阿尔特施泰滕，瑞士）从主模型制作40个印模。将印模分为四组：A组（对照组，10个未处理的印模），B组（10个用5.25%次氯酸钠[NaOCl]消毒的印模），C组（10个用2%戊二醛消毒的印模），D组（10个在134°C下高压灭菌18分钟的印模）。随后，使用IV型石膏产品（Gelstone，BK Giulini Chemie，路德维希港/莱茵，德国）制作石膏模型。通过测量基牙间测量值（基牙之间）和基牙内测量值（基牙的直径和高度）来评估所得模型的尺寸精度。这些测量使用精度为0.001毫米的万能测量显微镜（奥林巴斯体视显微镜B061成像公司，东京，日本）进行。然后将研究组的石膏模型尺寸与对照组的尺寸进行比较。使用显著性水平α = 0.05的单因素方差分析进行数据分析。
在不同浸泡时间下，用5.25% NaOCl和2%戊二醛进行化学消毒的AFFINIS印模在基牙内和基牙间测量值上显示出轻微膨胀。在134°C下高压灭菌18分钟的印模在基牙内和基牙间测量值上显示出轻微收缩。尺寸变化在统计学上无显著意义，且实验组内尺寸变化百分比在临床可接受范围内（α < 0.5）。
AFFINIS聚乙烯基硅氧烷在进行化学消毒和蒸汽高压灭菌后仍保持适合临床使用的尺寸稳定性。
