A New Approach for Controlling Hemostasis During Canal Treatment

A new device (HYBENX®, EPIEN Medical, Saint Paul, MN, USA) has been developed with the purpose of destroying dental biofilm. The material is a mixture of hydroxybenzenesulfonic acid (37%) and hydroxymethoxybenzene acids (23%), sulfuric acid (28%), and water (12%).

This device has been successfully used in periodontology. Recent studies (Pini-Prato et al. 2016a, Isola et al. 2017) have demonstrated the effectiveness of the oral tissue decontaminant material in the treatment of clinical cases showing acute periodontal abscess without the use of systemic or local antibiotics. Similar favorable effects were obtained in the treatment of peri-implant mucositis and peri-implantitis (Pini-Prato et al. 2016b, Lopez et al. 2016). In addition, a randomized controlled trial (RCT) also demonstrated beneficial effects of the material in the treatment of oral aphthae (Porter et al. 2009).

Based on this scientific information, a clinical and microbiological study has been planned using the decontaminant device in cases of teeth with necrotic pulp with the aim to destroy the dental biofilm of root canals. The ability of the decontaminant device to immediately stop bleeding during canal instrumentation was found out accidentally during the procedures of this still unpublished trial.

Due to this fact, the authors were interested in evaluating the coagulation property of the material. The purpose of this study was to test the reduction of root canal bleeding in terms of significant percentage change for millimeters of blood in the canal at 2 different time points (before and after treatment with HybenX ) A single center, participants and data analyst blind, two-arm, randomized, placebo controlled clinical trial study was performed following the CONSORT statement in the Endodontics Department, University Hospital Florence Careggi, Florence, Italy.

The study population consisted of patients that were treated by Endodontics Department of the University Hospital of Florence Careggi, Italy. Subject inclusion criteria were: patients aged between 20 and 60 years, able and willing to sign a consent form, single-rooted teeth with necrotic pulp confirmed by electric vitality test, associated with healthy periodontium, physiologic sulcus depth (\<3 mm), and absence of bleeding on probing of the involved teeth.

Exclusion criteria were: patients with systemic diseases using anticoagulants, antibiotics, or anti-inflammatory therapies in the last 30 days, patients with allergy to sulfur in any form, and pregnancy. All subjects were informed of the nature and potential risks and benefits of their participation in the study. They also received information on the duration of the procedure, and the possible intraoperative and postoperative complications.

Treatment The root canal therapy procedure was standardized and limited to one experienced endodontist (R.P.). Treatments were performed at the Endodontics Departments of the University Hospital of Florence Careggi, Italy, under local anesthesia using 1.8 mL mepivacaine hydrochloride (Optocaine; Molteni Dental SRL, Scandicci, Italy), and the teeth were isolated with rubber dams. After preparing the access cavity, the working length was determined with an electronic apex locator (Propex II Dentsply Maillefer Instruments, Ballaigues, Switzerland) with a size 10 k-file. Root canals were shaped using ProTaper Universal NiTi files (Dentsply Maillefer Instruments, Ballaigues, Switzerland) in the following sequence: S1, S2, F1, F2, F3 until each instrument reached the working length. After each instrument, the root canals were rinsed with NaClO (Niclor 5, Ogna, Italy) using a syringe with a side-vented 30 G needle. ProTaper NiTi instruments were driven with an endodontic motor (XSmart Endo Motor, Dentsply Maillefer Instruments, Ballaigues, Switzerland) with a 16:1 contrangle set up as suggested by the manufacturer.

After the root canal, shaping was performed, and a first sterile paper point was introduced in the root canal, up to the working length, for 10 seconds to detect blood presence.

With a caliber, on the sterile paper cone, the millimeters of blood present within the root canal were measured.

Only the teeth that at this point showed 1 or more millimeters of blood within the root canal were included in the present study and randomized to the two experimental groups.

Before further treatment, the teeth were allocated to an experimental (HybenX) or a control group (sterile saline solution) according to an uneven block randomization designed by the statistician (A.N.). For each tooth, a closed envelope was opened in a consecutive order, assigning the tooth to either the experimental or the control group HybenX was approved as a Class I CE medical device by the Italian Ministry of Health (no. 483768) on February 7, 2012.

HybenX Group The material was introduced inside the root canal using the pre-dosed syringe for 20 seconds with a sterile paper point with and up and down movement up to the working length.

Finally, the canal was rinsed with sterile water using a syringe with a side-vented 30 G needle 1 mm shorter than the working length.

A second sterile paper point was introduced in the root canal, up to the working length, for 10 seconds to detect the presence of blood and the millimeters of blood inside the root canal was measured again according the previous criteria.

Statistical Analysis Data were analyzed using SAS Version 9.3 software (SAS Institute, Inc., Cary, NC). A preliminary Levene's test was performed to verify the homogeneity of variance for the percentage change in the two groups.

Since the two groups showed homogeneity of the variance a t-test was performed to verify the null hypothesis by using a type I error equal to 0.05.

In order to confirm the firmness of the results a Wilcoxon non-parametric test was also carried out.