Paknahad Maryam, Dehghani Ali, Khaleghi Iman, Eghildespour Mahsa, Mortazavi Ghazal, Mortazavi Seyed Mahammad Javad
Oral and Dental Research Center, Oral and Maxillofacial Radiology Department, Dental Faculty, Shiraz University of Medical Sciences, Shiraz, Iran.
Department of Oral and Maxillofacial Pathology, Biomaterial Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
J Biomed Phys Eng. 2025 Jun 1;15(3):263-270. doi: 10.31661/jbpe.v0i0.2210-1551. eCollection 2025 Jun.
Dental amalgam is a popular restorative material used in posterior teeth. Hair dryers can emit electromagnetic fields (EMFs) that may affect the microleakage of the amalgam-tooth interface.
The aim of this experimental study was to investigate whether the EMFs produced by commercial hair dryers could cause microleakage in amalgam restorations.
In this experimental study, a total of 100 human extracted teeth without cavities were selected and prepared for class V preparations on their buccal aspects. The teeth were divided into five groups (G1-G5), each containing 20 teeth. Group 1 served as the control group and was not subjected to any treatment. Groups 2 to 5 were exposed to EMFs of a hair dryer (2000 W, 220 V, and 50 Hz). Groups 2 and 3 were exposed to "EMFs +Hot Air" for 20 min at 10 cm and 30 min at 5 cm, respectively. Groups 4 and 5 were exposed to "EMFs +Cool Air" for 20 min at 10 cm and 30 min at 5cm, respectively. After preparation, the sectioned teeth were evaluated for microleakage using dye penetration measurement.
The microleakage scores showed a significant difference among the three exposure groups (G2, G3, and G5) and the control group (=0.001, 0.002, and 0.01, respectively). However, there was no significant difference between G4 and G1. The microleakage score in G2 was higher than that in G4.
This study suggests that the common use of hair dryers can lead to damage in amalgam restorations.
牙科汞合金是一种常用于后牙的修复材料。吹风机可发射可能影响汞合金与牙齿界面微渗漏的电磁场（EMF）。
本实验研究旨在调查商用吹风机产生的电磁场是否会导致汞合金修复体出现微渗漏。
在本实验研究中，共选取100颗无龋的人离体牙，并在其颊面制备V类洞形。将牙齿分为五组（G1 - G5），每组20颗牙。第1组作为对照组，不进行任何处理。第2至5组暴露于吹风机的电磁场（2000W、220V和50Hz）。第2组和第3组分别在距离10cm处暴露于“电磁场 + 热风”20分钟，在距离5cm处暴露30分钟。第4组和第5组分别在距离10cm处暴露于“电磁场 + 冷风”20分钟，在距离5cm处暴露30分钟。制备完成后，使用染料渗透测量法评估切片牙齿的微渗漏情况。
三个暴露组（G2、G3和G5）与对照组之间的微渗漏评分存在显著差异（分别为=0.001、0.002和0.01）。然而，G4组和G1组之间无显著差异。G2组的微渗漏评分高于G4组。
本研究表明，经常使用吹风机可能会导致汞合金修复体受损。
