_Applied_  
_sciences_  
_Article_  
**Influence of 17% EDTA and _Sapindus mukorossi_ on the Surface Property of Protaper Gold**  
**Priority of Protaper Gold Rotary Endodontic Instruments**  
**[PERSON] 1, [PERSON] 2, [PERSON] 1, [PERSON] 3, [PERSON] 1, [PERSON] 4, [PERSON] 5, [PERSON] 5, [PERSON] 6, [PERSON] 7\({}^{\copyright}\)6, [PERSON] 8, [PERSON] 9,\({}^{\copyright}\)7 and [PERSON] 9\({}^{\copyright}\)7**  
Footnote 1: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 2: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 3: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 4: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 5: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 6: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 7: [[https://www.mdpi.com](https://www.mdpi.com)]([https://www.mdpi.com](https://www.mdpi.com))  
resistance compared to conventional stainless steel (SS) files [3]. Apart from having various benefits, unexpected fractures of NiTi rotary instruments can occur during clinical use due to flexural fatigue and torsional stress [4]. Among various NiTi systems used, Protaper NiTi rotary instruments have been used most commonly in clinical dentistry [5]. The files of the Protaper NiTi rotary system possess different tapers and file lengths, along with passive tips and a convex triangular design. The geometry of the ProTaper Universal system (Dentsply, Sirona, York, PA, USA) and that of the ProTaper Gold rotary system (Dentsply, Sirona, York, PA, USA) are the same with advancement in the metallurgy in the layer system [6]. ProTaper Gold allows greater flexibility and cyclic fatigue, thus respecting the initial anatomy of the S-shaped canals [6]. The aim of root canal treatment (RCT) is to clean and shape the root canals by considering mechanical, chemical and biological objectives [7]. Microorganisms are the key contributing factors in periapical and pulpal diseases. In order to eliminate bacteria from root canal system, the mechanical instrumentation is required which leads to production of layer of debris called the \"smear layer\" [8]. The literature has reported that the smear layer is critical to root canal treatment failure [9; 10]. The presence of a smear layer creates a barrier for the disinfectants to penetrate within dentine chips leading to root canal treatment failure [11]. During canal shaping and cleaning, endodontic files are in continuous contact with the root canal irrigants. However, short-term interaction with these irrigants can influence the surface properties of the NiTi rotary instruments used [12]. Various therapeutic and chemical products for endodontic irrigation include QMix, MTAD, 17% ethylene diamine tetra acetic acid (EDTA), calcium hydroxide, chlorweldine gluconate, sodium hypochlorite (NaOCI), and saline [13; 14]. EDTA acts as a decalcifying agent and removes the inorganic component of the smear layer. However, it does not remove the organic debris attached to the canal surface [15]. Although EDTA is effective in removing the smear layer, there are concerns about dentin erosion. Moreover, the previous literature has revealed that EDTA can cause damaging effects on the NiTi rotary files used for canal preparation due to its low pH, resulting in surface roughness (Ra) and change in root mean square (RMS) [12; 16; 17].