Effects of Different Irrigation Activation Techniques on the Healing of Large Periapical Lesions: A Prospective Clinical Study
Phase: NA
Conditions: Periapical Periodontitis, Irrigation Activation, Lasers
Sponsor: Recep Tayyip Erdogan University

Effects of Different Irrigation Activation Techniques on the Healing of Large Periapical 
Lesions: A Prospective Clinical Study 
Clinical Trial Number: NCT06991803 
Date: 30.06.2024 
 
Study Protocol 
MATERIALS AND METHODS 
 
Local ethics committee approval was obtained from the Recep Tayyip Erdoğan University Ethical 
Committee (No: 2023/136). All the participants were informed about the study protocol, and 
written informed consent was obtained. Sample size calculation The G Power 3.1.9.4 (University 
Kiel, Germany) program was used to calculate the effect size. The effect size was calculated on 
the basis of the data of Verma et al. (14), who compared the success of different irrigation 
techniques in healing after one year. On the basis of the chi-square test data, an effect size of 
0.388 was found to be sufficient for significance, and it was calculated that a total of at least 110 
samples were required with a type 1 error of 0.05 and 90% power. 
Patient selection 
 
Vertucci Class I single-rooted mandibular premolars with asymptomatic apical periodontitis and 
a periapical index (PAI) score of 3 or higher were included in the study. Patients with systemic 
diseases, bone metabolism diseases and/or drugs that affect bone metabolism (steroids and 
bisphosphonates) were excluded from the study. Immunocompromised patients, patients with 
a history of radiotherapy, pregnant patients, teeth with Miller 2 or more mobility, teeth with a 
periodontal pocket depth of ≥5 mm, teeth with internal and external resorption, and teeth with 
vertical and horizontal root fractures were excluded. Out of 150 patients aged 18 years and over, 
a total of 18 patients who refused to participate or did not meet the inclusion criteria were 
excluded from the study, and 132 patients were included. Pretreatment panoramic radiographs 
were obtained with a Planmeca Promax 2D S2 device (Planmeca Romexis, Helsinki, Finland). The 
patients were positioned so that the sagittal plane was parallel to the vertical plane of the dental 
panoramic machine and the Frankfurt plane was parallel to the floor. The same radiographic 
exposure settings (66 kVp, 8 mA and 16.6 second exposure time) were used for all patients.  
 
 
 
 

For 2 each tooth, the vertical, horizontal and diagonal dimensions passing through the center of 
the lesion were measured via ImageJ v1.52 software (National Institutes of Health, Bethesda, 
United States), and the largest dimension obtained was recorded as the preoperative lesion 
diameter (15). 
Clinical Procedure 
 
Figure 1 shows the flow diagram of the study, summarizing the treatment methodology. After the 
teeth were isolated with a rubber dam, the endodontic access cavity was opened with a sterile 
diamond rond bur under water cooling. Then, #10-15 K-type hand files (Dentsply Maillefer, 
Ballaigues, Switzerland) were inserted into the canals, and after determining point 0.0 with the 
Root ZX mini electronic apex locator (J. Morita Co., Tokyo, Japan), the working length was 
determined to be 0.5 mm shorter than this point and confirmed radiographically. When a 
discrepancy was observed, the apex locator was considered correct. After the initial apical 
diameter with the largest K-type file trapped in the working length was determined, the root 
canals were prepared with ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland) up to 
3 sizes larger than the initial diameter via a torque-controlled endodontic motor (SybronEndo, 
Glendora, CA, USA) in 300 rpm/2–5.2 Ncm rotation mode. Between each file, the canals were 
irrigated with 5 ml of 2.5% NaOCl. In retreatment cases, after opening the access cavity under 
rubber dam isolation, the guta percha was removed with RT files (EndoArt RT, İnci Dental, 
Turkey), and the rest of the procedure was performed in the same manner as for primary root 
canal treatment. After the preparation was completed, final irrigation was applied via the 
irrigation method. 
Control Group (Conventional Syringe Irrigation) 
In this group, the traditional syringe method was used for final irrigation of the root canals. The 
canals were irrigated with 6 mL of 17% EDTA solution, 2 mL of saline and, finally, 6 mL of 2.5% 
NaOCl, and a 30-gauge perforated irrigation needle placed 1–2 mm shorter than the working 
length was used. During irrigation, 1–2 mm up-down movements were made with a constant low 
pressure. 
Group 1 (MDA) 
After the root canal was filled with irrigation solution, a gutta-percha cone compatible with the 
master file was positioned 1 mm behind the working length and moved up and down with 100 
strokes/minute for activation. 
 
 

Group 2 (Sonic Activation) 
Sonic activation was performed via the Easydo Activator device (EA; Easyinsmile (Weixiaomeichi, 
Changsha, China). While the solution was present in the canal, the needle t ip of the device was 
placed in the canal 2 mm behind the determined working length, and the solutions were 
activated at the recommended power setting. 
Group 3 (PUI) 
Solutions were activated via ultrasonic tips (mode:E, setting:6) (DTE, Guilin Woodpecker Co., 
Guilin, Guangxi, China) and an ultrasonic device (DTE S6 Led, Guilin Woodpecker Co., Guilin, 
Guangxi, China). An ultrasonic tip one size smaller than the master apical file was used 2 mm 
behind the working length without contacting the walls. 
Group 4 (PIPS) 
A Fotona Er:YAG laser device (LightWalker Fotona, Ljubljana, Slovenia) was used for activation. 
A special conical and radial fiber tip (PIPS 300/14, Fotona) was placed in the coronal part of the 
pulp chamber, and the irrigation solutions in the canal were activated in SSP mode (50 μs, 0.3 W, 
15 Hz and 20 mJ) with the air and water settings turned off. 
Group 5 (SWEEPS) 
A Fotona Er:YAG laser device (SWEEPS 600, Fotona) with an 8.5 mm long and 600 µm diameter 
tapered fiber tip was used for activation. The device was set to SWEEPS mode with two ultrashort 
micropulses (25 μs) continuously changing at 0.3 W, 20 mJ, and 15 Hz. The tip was placed in the 
pulp chamber, and the solution was activated with the air and water settings turned off. In all the 
activation groups, 2 mL of 17% EDTA solution (SAVER, Prime Dental, Turkey) was activated for 20 
s, and this process was repeated 3 times for a total of 6 mL of EDTA activation in 1 min. Then, 2 
mL of saline was applied to the canals for 20 s to prevent the chemical interaction of NaOCl and 
EDTA. Afterward, 2 mL of 2.5% NaOCl solution (MICROVEM, Turkey) was activated for 20 s, and 
this procedure was repeated 3 times for a total of 6 mL of NaOCl solution activation in 1 minute. 
After the final irrigation, the canals were dried with paperpoint (DiaDent, Heungdeok-gu, Korea) 
and obturated via the cold lateral compaction method via an ADSeal (Meta Biomed, Cheongju, 
South Korea) sealer and gutta-percha. The gutta-percha was cut 1 mm below the cemento- 
enamel junction, and coronal restoration was performed with composite resin (Llis, FGM, 
Joinville, Brazil). All procedures were performed by a single operator (M.Ç.). 
 
 
 

Healing evaluation 
PAI score and lesion diameter At the 12-month follow-up, panoramic radiographs were taken 
using the same settings as those used for pretreatment radiography. PAI scores of the treated 
teeth were recorded, and patients were classified as "healed" (PAI<3) or "unhealed" (PAI≥3). PAI 
scoring was performed by 2 endodontists, and in cases of disagreement, a consensus was 
reached by discussion. Additionally, the widest diameter of the lesion at the follow-up session 
was measured by an endodontist (M.Ç.) The same method was used for the preoperative 
measurements. The researchers who conducted the PAI and lesion size evaluations were blinded 
to the irrigation method and preoperative measurements. 
Fractal analysis 
 
Fractal analysis (FA) was performed by an experienced oral and maxillofacial radiologist (D.N.G.) 
who was blinded to the activation method and used the fractal box counting method on 
panoramic radiographs with ImageJ. The program was downloaded from the internet at 
https://imagej.nih.gov/ij/download.html. To standardize the size and location of the ROI, a 
parallel line forming a right angle to the apical and long axes of the tooth was placed 1 mm apical 
to the root apex (Figure 1). The sequence of steps followed when FD analysis was performed was 
as follows (Figure 2): All digital images were opened in ImageJ v. 1.52 software (National 
Institutes of Health), and 30x30 pixel sections were taken from the determined regions and saved 
in 'tif' format. After the area of interest to be analyzed was cropped, it was saved in 8-bit format 
and copied. A Gaussian filter (sigma= 35 pixels) was applied to the duplicated image. The blurred 
image was subtracted from the original image via subtraction. A value of 128 was added to each 
pixel location, and 128 was set as the threshold value regardless of the initial brightness of the 
image. The 128 brightness threshold image was converted to binary format. An erosion and 
dilatation process was applied. The inverted image was skeletonized, and FD analysis was applied 
to the skeletonized image via the 'box-counting' function. To assess intraobserver reliability, the 
lesion diameter and fractal measurements were conducted twice with 2-week intervals by the 
same researchers in 20% of the teeth involved in the study. 
 
 
 
 
 
 

Effects of Different Irrigation Activation Techniques on the Healing of Large 
Periapical Lesions: A Prospective Clinical Study 
 
Clinial Trial Number: NCT06991803 
Date: 30.06.2024 
 
Statistical analysis  
The Jamovi 2.3.28 statistical program was used for statistical analysis. Normal distribution in the 
comparisons was evaluated by the Shapiro‒Wilk test, Kolmogorov‒ Smirnov test, Anderson‒ 
Darling test and Q‒Q graph. Homogeneity between variances was analyzed by Levene's test. 
Since sex data were categorical, the differences between the groups were analyzed via the chi-
square test. Since the distribution of age between groups was found to be normal, it was analyzed 
by Welch's one-way ANOVA test. Although a normal distribution was obtained in fractal analysis, 
Welch's one-way ANOVA test was preferred for the comparison of irrigation groups because the 
variances were not homogeneously distributed, and pairwise comparisons were made with the 
Games‒Howell test. Before and after comparisons within each group, paired sample t tests were 
used. 
Since a normal distribution could not be obtained, the Kruskal‒Wallis test was preferred for the 
comparison of irrigation groups for lesion size, and pairwise comparisons were made with the 
Dwass-Steel-Critchlow-Fligner test. Before and after comparisons within each group, the 
Wilcoxon rank test was used. The significance level for the statistical analysis was set to p<0.05. 
Additionally, intraobserver reliability was evaluated for fractal and lesion size measurements via the 
concordance correlation coefficient (CCC). 

 
 
 
 
Name of the Study: Effects of Different Irrigation Activation Techniques on 
the Healing of Large Periapical Lesions: A Prospective Clinical Study 
   Clinical Trial Number: NCT06991803 
Date: 30.06.2024 
 
PLEASE READ CAREFULLY! 
 
You are invited to participate in our research. Before deciding to take part, you need to 
understand the purpose of the study and make a free and informed decision. Please read this 
information carefully and feel free to ask any questions you may have. 
Participation in this study is entirely voluntary. You have the right to refuse participation or 
withdraw from the study at any time. Your participation will be interpreted as your consent to 
join the research. Do not feel any pressure while answering the questions on the forms. All 
information gathered will be used solely for research purposes. 
PURPOSE OF THE STUDY: This study aims to compare the healing rates of single-rooted 
mandibular teeth with large periapical lesions of endodontic origin using different irrigation 
activation methods (sonic, ultrasonic, Er:YAG laser, manual dynamic activation), through 
fractal analysis of panoramic radiographs taken before treatment and one year after 
treatment. 
• WHAT ARE THE CONDITIONS OF PARTICIPATION? 
 
To be eligible for participation, the following criteria must be met: 
RECEP TAYYIP ERDOGAN UNIVERSITY FACULTY OF 
MEDICINE NON-INTERVENTIONAL CLINICAL RESEARCH 
ETHICS BOARD 

Patients examined at Recep Tayyip Erdoğan University Faculty of Dentistry, Department of 
Endodontics 
Patients aged 18 and over 
Have accepted the Endodontic Consent Form and Study Participation Form 
Diagnosed with apical periodontitis requiring primary endodontic treatment with a PAI 
(periapical index score) of 3 or higher in single-rooted mandibular teeth 
Diagnosed with apical periodontitis requiring retreatment with a PAI score of 3 or higher in 
single-rooted mandibular teeth 
Having good oral hygiene 
Participants will be included based on the irrigation activation technique used during routine 
endodontic treatment. 
• WHAT KIND OF APPLICATION WILL BE DONE? 
 
Routine root canal or retreatment procedures will be applied. If necessary, irrigation 
activation techniques will be used. 
• WHAT ARE MY RESPONSIBILITIES? 
 
You must regularly attend treatment and follow-up appointments as part of the study. 
• WHAT IS THE NUMBER OF PARTICIPANTS? 
 
A total of 132 participants are planned to be included in the study. 
• HOW LONG WILL MY PARTICIPATION LAST? 
 
Endodontic treatment is expected to take approximately 1 hour. You will be asked to 
participate in a follow-up one year after treatment.. 
• WHAT ARE THE POSSIBLE BENEFITS EXPECTED BY 
PARTICIPATION IN THE STUDY? 
Observing the effect of endodontic treatment and irrigation activation techniques on the 
healing of teeth with large lesions. 
• WHAT ARE 
THE 
POSSIBLE 
RISKS 
EXPECTED 
BY 
PARTICIPATION IN THE STUDY? 
No risks beyond routine root canal treatment complications are expected. 

• WHAT ARE THE DRUGS/NUTRIENTS KNOWN TO BE 
CONTROLLED TOGETHER DURING THE RESEARCH 
PROCESS? 
There are no known medications or foods that pose a risk. 
 
 
• UNDER WHAT CONDITIONS CAN I BE EXCLUDED FROM 
THE RESEARCH? 
You may be excluded if tooth extraction, apical surgery, or similar indications arise during 
treatment. 
 
• WHO IS LIABLE/RESPONSIBLE IN CASE OF ANY DAMAGE 
AND WHAT WILL BE DONE? 
The treating physician and their supervisor are responsible for any harm that may occur. 
• WHO SHOULD I CALL FOR PROBLEMS THAT MAY 
ARISE DURING THE RESEARCH PROCESS? 
If you have any questions or require additional information, please contact: 
Name: Medine ÇİÇEK 
Position: Research Assistant 
   Phone: +905442745525 
• WILL THE EXPENSES IN THE SCOPE OF THE STUDY BE 
COVERED? 
There is no cost to the patient for procedures covered in this study. 
• IS THERE AN INSTITUTION SUPPORTING THE STUDY? 
 
The study will be conducted within the Faculty of Dentistry at Recep Tayyip Erdoğan 
University. 
• WILL ANY PAYMENT BE MADE DUE TO MY PARTICIPATION 
IN THE STUDY? 
No payment will be provided. 

• WHAT SHOULD I DO IF I DO NOT AGREE TO PARTICIPATE 
IN THE STUDY OR LEAVE THE STUDY? 
Participation is entirely voluntary. Patients who do not agree to participate will not be 
included in follow-up measurements after routine treatment. You can withdraw at any time 
without having to state a reason, and without facing any negative consequences. 
• CAN CONFIDENTIALITY BE PROVIDED REGARDING 
INFORMATION REGARDING MY PARTICIPATION? 
Participant identity information will be kept confidential. Age, gender, and radiograph data 
will be used for statistical analysis. 
 
 
Consent to Participate in the Study: 
I have read the information provided above and understand the purpose and scope of the 
study, as well as my responsibilities as a volunteer. The researcher named below has 
explained the study to me both in writing and verbally, and I had the opportunity to ask 
questions and received satisfactory answers. I was also informed verbally of the possible 
risks and benefits. I understand that I may withdraw from the study at any time without having 
to give a reason and that doing so will not result in any negative consequences. 
Under these conditions, I voluntarily agree to participate in this study without any pressure or 
coercion. I understand that refusing to sign this form will not affect any legal rights I may have. 
A signed and dated copy of this form has been provided to me. 
 
 
VOLUNTEER 
NAME & SURNAME 
SİGNATURE 
ADDRESS 
PHONE & FAX 
DATE 

RESPONSIBLE RESEARCHER 
NAME & SURNAME 
R.A. Medine Çiçek 
SİGNATURE 
ADDRESS 
Recep Tayyip Erdoğan University 
Faculty of Dentistry, Department 
of Endodontics 
PHONE & FAX 
(0464) 222 00 00 
DATE