Apical PeriodontitisNCT07903285
Laser-Activated Versus Passive Ultrasonic Irrigation in Endodontic Retreatment
A study testing Photon-Induced Photoacoustic Streaming, Shock Wave Enhanced Emission Photoacoustic Streaming and Passive Ultrasonic Irrigation in people with Apical Periodontitis, run by Inonu University at 1 site in Turkey (Türkiye).
Trial summary
This study will compare three methods of activating the final irrigation solution in reducing living bacteria inside the root canals of teeth that require root canal retreatment because of apical periodontitis, an inflammatory condition of the tissues around the root tip. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Apical Periodontitis
- What is being tested?
- Photon-Induced Photoacoustic Streaming, Shock Wave Enhanced Emission Photoacoustic Streaming and Passive Ultrasonic Irrigation
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 90 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- Nov 2026to May 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults aged 18-65 years who are systemically healthy (American Society of Anesthesiologists physical status classification I).
- A previously root canal-treated, single-rooted tooth with a single root canal requiring nonsurgical root canal retreatment.
- Persistent or secondary apical periodontitis with a Periapical Index (PAI) score of at least 3.
- Root canal filling material considered completely removable by nonsurgical means.
- Sufficient coronal tooth structure to allow rubber dam isolation.
- Only one tooth per participant will be included.
Who cannot join
- Antibiotic use within the preceding 3 months.
- Pregnancy or breastfeeding.
- American Society of Anesthesiologists physical status classification II or higher.
- Periodontal probing depth greater than 4 mm in the study tooth.
- Root fracture, perforation, or root resorption in the study tooth.
- A calcified or non-negotiable root canal.
- Acute abscess or active drainage.
- A non-removable post or a separated instrument in the root canal.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site
Inonu University, Faculty of Dentistry, Department of Endodontics
Malatya, 44280
Ebru Ozcan, +90 536 706 7925, ebru_ozcan@inonu.edu.tr
About this study
Official title: Comparison of the Efficacy of PIPS and SWEEPS Laser-activated Irrigation Versus Passive Ultrasonic Irrigation in Reducing Viable Intracanal Bacteria During Endodontic Retreatment of Teeth With Apical Periodontitis: a Culture-based Randomized Controlled Trial
This study will compare three methods of activating the final irrigation solution in reducing living bacteria inside the root canals of teeth that require root canal retreatment because of apical periodontitis, an inflammatory condition of the tissues around the root tip. The three methods are photon-induced photoacoustic streaming (PIPS), shock wave-enhanced emission photoacoustic streaming (SWEEPS), and passive ultrasonic irrigation (PUI). Ninety adults requiring retreatment of a single-rooted, single-canal tooth will be randomly assigned to three groups; all treatment steps other than the activation method will be identical. Root canal samples will be collected at several stages of the single-visit treatment, and living bacteria will be counted using laboratory cultures. In addition, real-time PCR will be used to measure the relative amount of Enterococcus faecalis DNA compared with total bacterial DNA. Because PCR cannot distinguish living from dead bacteria, these molecular results will be interpreted as complementary to the culture findings.
Read the detailed description
Background: The main cause of persistent or secondary apical periodontitis in root canal-treated teeth is the persistence of bacteria in difficult-to-access areas of the root canal system. Irrigation activation aims to improve the delivery of irrigating solutions to these areas. PIPS and SWEEPS techniques using an Er:YAG laser generate pressure waves within the irrigating solution without placing the laser tip inside the root canal. A clinical study in teeth with primary apical periodontitis found no difference in bacterial reduction between SWEEPS and passive ultrasonic irrigation (PUI); however, that study used a molecular method that can also detect DNA from dead bacteria. The effects of these three methods on viable bacterial load in root canal retreatment cases have not been compared using culture.
Objective: To compare the efficacy of final irrigant activation with PIPS or SWEEPS versus PUI in reducing viable total intracanal bacteria and viable Enterococcus faecalis during single-visit nonsurgical root canal retreatment of single-rooted, single-canal teeth with apical periodontitis. A secondary objective is to evaluate changes in the relative quantity of E. faecalis DNA, normalized to total bacterial 16S rRNA, across sampling stages using real-time PCR.
Materials and Methods: Ninety patients will be allocated to the PIPS, SWEEPS, and PUI groups (n = 30 per group) using block randomization. Root canal filling material will be removed without solvents, and chemomechanical preparation will be performed using Reciproc Blue R40 and 5% NaOCl. A sterility control sample (S0) will be collected, and intracanal samples will be obtained after removal of the root canal filling (S1), after chemomechanical preparation (S2), and after final irrigant activation (S3). Group allocation will be revealed only after S2 sampling. In all groups, the type, concentration, volume, sequence, and total activation time of the irrigants will be identical (3 x 2 mL of 5% NaOCl, 20 seconds of activation each; total 60 seconds).
Samples will be transported to the microbiology laboratory in reduced transport fluid and processed within 2 hours. S1, S2, and S3 samples will be divided into culture and molecular aliquots; S0 will be analyzed by culture only. Viable total bacterial load and viable E. faecalis levels will be determined by culture and reported as CFU/mL. In the molecular aliquots, an E. faecalis-specific gene region and the universal bacterial 16S rRNA gene region will be targeted by real-time PCR; relative quantity will be calculated using the 2^(-delta Ct) and 2^(-delta delta Ct) methods. Laboratory personnel and the statistician will be blinded to group allocation.
Outcomes and Analysis: The primary outcome is the reduction in viable total bacterial load during final irrigant activation, calculated as log10 CFU/mL (S2) minus log10 CFU/mL (S3). This reduction will be compared among groups using the Kruskal-Wallis test, followed by Dunn's test with Holm correction. Secondary outcomes include the proportion of negative cultures at S3, reductions from S1 to S2 and from S1 to S3, changes in viable E. faecalis, and changes in the relative quantity of E. faecalis DNA determined by real-time PCR. Molecular findings will be interpreted as complementary to culture results, as real-time PCR cannot distinguish between viable and dead bacteria.
- Conditions
- Apical Periodontitis
- Being tested
- Photon-Induced Photoacoustic Streaming, Shock Wave Enhanced Emission Photoacoustic Streaming, Passive Ultrasonic Irrigation
- Keywords
- Endodontic Retreatment, Laser-Activated Irrigation, PIPS, SWEEPS, Passive Ultrasonic Irrigation, Er:YAG Laser, Bacterial Culture, Enterococcus faecalis, Quantitative Real-Time PCR
- Medical subject headings
- Periapical Periodontitis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Photon-Induced Photoacoustic StreamingDevice
Also called PIPS
After S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia) in PIPS mode at 20 mJ, 15 Hz, 0.3 W and 50-microsecond pulse duration, with water and air spray off. A tapered PIPS 600/9 tip (600 micrometers, 9 mm) will be held stationary in the access cavity above the canal orifice without insertion into the canal. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout.
Shock Wave Enhanced Emission Photoacoustic StreamingDevice
Also called SWEEPS
After S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia) in AutoSWEEPS mode at 20 mJ, 15 Hz and 0.3 W, with water and air spray off. A Radial SWEEPS 600/9 tip (600 micrometers, 9 mm) will be held stationary in the access cavity above the canal orifice without insertion into the canal. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout.
Passive Ultrasonic IrrigationDevice
Also called PUI
After S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with a Woodpecker DTE S6 ultrasonic device (Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, China) and an ED60 tip in Endo mode at power level 2. The tip will be positioned 2 mm short of the working length and activated without contacting the root canal walls. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout.
| Study group | Role | What they receive |
|---|---|---|
| PIPS Laser-Activated Irrigation | Experimental | Thirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using photon-induced photoacoustic streaming (PIPS) with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia). Receives: Device: Photon-Induced Photoacoustic Streaming |
| SWEEPS Laser-Activated Irrigation | Experimental | Thirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using shock wave-enhanced emission photoacoustic streaming (SWEEPS) with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia). Receives: Device: Shock Wave Enhanced Emission Photoacoustic Streaming |
| Passive Ultrasonic Irrigation | Active comparator | Thirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using passive ultrasonic irrigation (PUI) with an ultrasonic device (Woodpecker DTE S6, Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, China). Receives: Device: Passive Ultrasonic Irrigation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Reduction in Viable Total Cultivable Intracanal Bacterial Load From S2 to S3
Viable total cultivable intracanal bacteria will be quantified by culture as colony-forming units per milliliter (CFU/mL). For each participant, the reduction will be calculated as log10 CFU/mL at S2 minus log10 CFU/mL at S3 and reported in log10 CFU/mL. The reduction will be compared among the PIPS, SWEEPS and passive ultrasonic irrigation groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from completion of chemomechanical preparation (S2) to immediately after final irrigant activation (S3).)
Secondary outcomes (6)
Reduction in Viable Total Cultivable Intracanal Bacterial Load From S1 to S2
Viable total cultivable intracanal bacteria will be quantified by culture as CFU/mL. For each participant, the reduction will be calculated as log10 CFU/mL at S1 minus log10 CFU/mL at S2 and reported in log10 CFU/mL. This outcome reflects bacterial reduction during the common chemomechanical preparation phase and will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from root canal filling removal (S1) to completion of chemomechanical preparation (S2).)
Overall Reduction in Viable Total Cultivable Intracanal Bacterial Load From S1 to S3
Viable total cultivable intracanal bacteria will be quantified by culture as CFU/mL. For each participant, the overall reduction will be calculated as log10 CFU/mL at S1 minus log10 CFU/mL at S3 and reported in log10 CFU/mL. The overall reduction will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from root canal filling removal (S1) to immediately after final irrigant activation (S3).)
Reduction in Viable Intracanal Enterococcus faecalis Load From S1 to S2
Viable Enterococcus faecalis will be quantified by culture on selective medium (Enterococcosel agar), with suspected colonies confirmed by biochemical tests, and expressed as CFU/mL. For each participant, the reduction will be calculated as log10 CFU/mL at S1 minus log10 CFU/mL at S2 and reported in log10 CFU/mL. The reduction will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from root canal filling removal (S1) to completion of chemomechanical preparation (S2).)
Reduction in Viable Intracanal Enterococcus faecalis Load From S2 to S3
Viable Enterococcus faecalis will be quantified by culture on selective medium (Enterococcosel agar), with suspected colonies confirmed by biochemical tests, and expressed as CFU/mL. For each participant, the reduction will be calculated as log10 CFU/mL at S2 minus log10 CFU/mL at S3 and reported in log10 CFU/mL. The reduction will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from completion of chemomechanical preparation (S2) to immediately after final irrigant activation (S3).)
Overall Reduction in Viable Intracanal Enterococcus faecalis Load From S1 to S3
Viable Enterococcus faecalis will be quantified by culture on selective medium (Enterococcosel agar), with suspected colonies confirmed by biochemical tests, and expressed as CFU/mL. For each participant, the overall reduction will be calculated as log10 CFU/mL at S1 minus log10 CFU/mL at S3 and reported in log10 CFU/mL. The overall reduction will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (During the single treatment visit, from root canal filling removal (S1) to immediately after final irrigant activation (S3).)
Percentage of Participants With Culture-Positive Enterococcus faecalis After Final Irrigant Activation (S3)
A sample will be considered positive if at least one colony is detected on Enterococcosel agar and confirmed as Enterococcus faecalis by biochemical tests. The outcome is reported as the percentage of participants with an E. faecalis-positive S3 sample and will be compared among the three groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
Measured: Day 1 (Immediately after final irrigant activation (S3), during the single treatment visit.)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Oct 2026
- Study startNov 2026 (estimated)
- Primary completionMay 2027 (estimated)
- Study completionMay 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Apical PeriodontitisStudies of the same condition, open and under way.
- More trials run by Inonu UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This is a single-center, three-arm, parallel-group randomized controlled clinical trial. Ninety participants will be assigned in a 1:1:1 ratio to PIPS, SWEEPS, or passive ultrasonic irrigation using block randomization, with 30 participants per group.
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 90 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Inonu University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Elcin Tekin Bulut, Inonu University
- Investigators
- Elçin Tekin Bulut, DDS, PhD, Principal investigator, Inonu University, Faculty of Dentistry, Department of Endodontics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07903285
- Sponsor's protocol ID
- INU-ENDO-2026-01
- Status last verified
- Oct 2026
- First submitted
- 22 Oct 2026
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be made publicly available because participants' informed consent and the ethics committee approval do not cover data sharing with third parties. Aggregated results will be reported in the publication. De-identified data may be made available by the corresponding author upon reasonable request, subject to approval by the institutional ethics committee.
Publications
Meire M, De Moor RJG. Principle and antimicrobial efficacy of laser-activated irrigation: A narrative review. Int Endod J. 2024 Jul;57(7):841-860. doi: 10.1111/iej.14042. Epub 2024 Feb 10.
PubMed 38340037Siqueira JF Jr, Rocas IN. A critical analysis of research methods and experimental models to study the root canal microbiome. Int Endod J. 2022 Mar;55 Suppl 1:46-71. doi: 10.1111/iej.13656. Epub 2021 Nov 16.
PubMed 34714548Barbosa-Ribeiro M, Arruda-Vasconcelos R, Mendes Louzada L, Rodrigues Lima A, Marciano M, Affonso de Almeida JF, De-Jesus-Soares A, Zaia AA, Ferraz C, Gomes BP. Microbiological Investigation in Teeth with Persistent/Secondary Endodontic Infection in Different Stages of Root Canal Retreatment. Eur Endod J. 2020 Dec;5(3):219-225. doi: 10.14744/eej.2020.73626.
PubMed 33353920Hepsenoglu YE, Ersahan S, Erkan E, Gundogar M, Ozcelik F. Is SWEEPS better than PUI in reducing intracanal bacteria and inflammation in cases of apical periodontitis? Lasers Med Sci. 2024 Jul 16;39(1):182. doi: 10.1007/s10103-024-04117-9.
PubMed 39012553
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Efficacy of PIPS and SWEEPS Laser-activated Irrigation Versus Passive Ultrasonic Irrigation in Reducing Viable Intracanal Bacteria During Endodontic Retreatment of Teeth With Apical Periodontitis: a Culture-based Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT07903285
- Acronym / sponsor ID
- INU-ENDO-2026-01
- Conditions
- Apical Periodontitis
- Keywords
- Endodontic Retreatment, Laser-Activated Irrigation, PIPS, SWEEPS, Passive Ultrasonic Irrigation, Er:YAG Laser, Bacterial Culture, Enterococcus faecalis
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 90 participants (estimated)
- Lead sponsor
- Inonu UniversityUniversity, hospital or other
- Study start
- Nov 2026 (estimated)
- Primary completion
- May 2027 (estimated)
- Study completion
- May 2027 (estimated)
- First posted
- 29 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will compare three methods of activating the final irrigation solution in reducing living bacteria inside the root canals of teeth that require root canal retreatment because of apical periodontitis, an inflammatory condition of the tissues around the root tip. The three methods are photon-induced photoacoustic streaming (PIPS), shock wave-enhanced emission photoacoustic streaming (SWEEPS), and passive ultrasonic irrigation (PUI). Ninety adults requiring retreatment of a single-rooted, single-canal tooth will be randomly assigned to three groups; all treatment steps other than the activation method will be identical. Root canal samples will be collected at several stages of the single-visit treatment, and living bacteria will be counted using laboratory cultures. In addition, real-time PCR will be used to measure the relative amount of Enterococcus faecalis DNA compared with total bacterial DNA. Because PCR cannot distinguish living from dead bacteria, these molecular results will be interpreted as complementary to the culture findings.
Detailed description
Background: The main cause of persistent or secondary apical periodontitis in root canal-treated teeth is the persistence of bacteria in difficult-to-access areas of the root canal system. Irrigation activation aims to improve the delivery of irrigating solutions to these areas. PIPS and SWEEPS techniques using an Er:YAG laser generate pressure waves within the irrigating solution without placing the laser tip inside the root canal. A clinical study in teeth with primary apical periodontitis found no difference in bacterial reduction between SWEEPS and passive ultrasonic irrigation (PUI); however, that study used a molecular method that can also detect DNA from dead bacteria. The effects of these three methods on viable bacterial load in root canal retreatment cases have not been compared using culture.
Objective: To compare the efficacy of final irrigant activation with PIPS or SWEEPS versus PUI in reducing viable total intracanal bacteria and viable Enterococcus faecalis during single-visit nonsurgical root canal retreatment of single-rooted, single-canal teeth with apical periodontitis. A secondary objective is to evaluate changes in the relative quantity of E. faecalis DNA, normalized to total bacterial 16S rRNA, across sampling stages using real-time PCR.
Materials and Methods: Ninety patients will be allocated to the PIPS, SWEEPS, and PUI groups (n = 30 per group) using block randomization. Root canal filling material will be removed without solvents, and chemomechanical preparation will be performed using Reciproc Blue R40 and 5% NaOCl. A sterility control sample (S0) will be collected, and intracanal samples will be obtained after removal of the root canal filling (S1), after chemomechanical preparation (S2), and after final irrigant activation (S3). Group allocation will be revealed only after S2 sampling. In all groups, the type, concentration, volume, sequence, and total activation time of the irrigants will be identical (3 x 2 mL of 5% NaOCl, 20 seconds of activation each; total 60 seconds).
Samples will be transported to the microbiology laboratory in reduced transport fluid and processed within 2 hours. S1, S2, and S3 samples will be divided into culture and molecular aliquots; S0 will be analyzed by culture only. Viable total bacterial load and viable E. faecalis levels will be determined by culture and reported as CFU/mL. In the molecular aliquots, an E. faecalis-specific gene region and the universal bacterial 16S rRNA gene region will be targeted by real-time PCR; relative quantity will be calculated using the 2^(-delta Ct) and 2^(-delta delta Ct) methods. Laboratory personnel and the statistician will be blinded to group allocation.
Outcomes and Analysis: The primary outcome is the reduction in viable total bacterial load during final irrigant activation, calculated as log10 CFU/mL (S2) minus log10 CFU/mL (S3). This reduction will be compared among groups using the Kruskal-Wallis test, followed by Dunn's test with Holm correction. Secondary outcomes include the proportion of negative cultures at S3, reductions from S1 to S2 and from S1 to S3, changes in viable E. faecalis, and changes in the relative quantity of E. faecalis DNA determined by real-time PCR. Molecular findings will be interpreted as complementary to culture results, as real-time PCR cannot distinguish between viable and dead bacteria.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 3
- Model description
- This is a single-center, three-arm, parallel-group randomized controlled clinical trial. Ninety participants will be assigned in a 1:1:1 ratio to PIPS, SWEEPS, or passive ultrasonic irrigation using block randomization, with 30 participants per group.
| Arm | Type | Receives |
|---|---|---|
| PIPS Laser-Activated Irrigation | Experimental | Device: Photon-Induced Photoacoustic StreamingThirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using photon-induced photoacoustic streaming (PIPS) with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia). |
| SWEEPS Laser-Activated Irrigation | Experimental | Device: Shock Wave Enhanced Emission Photoacoustic StreamingThirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using shock wave-enhanced emission photoacoustic streaming (SWEEPS) with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia). |
| Passive Ultrasonic Irrigation | Active comparator | Device: Passive Ultrasonic IrrigationThirty participants will undergo standardized single-visit nonsurgical root canal retreatment. Following chemomechanical preparation, the final 5% NaOCl irrigant will be activated using passive ultrasonic irrigation (PUI) with an ultrasonic device (Woodpecker DTE S6, Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, China). |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Adults aged 18-65 years who are systemically healthy (American Society of Anesthesiologists physical status classification I).
- A previously root canal-treated, single-rooted tooth with a single root canal requiring nonsurgical root canal retreatment.
- Persistent or secondary apical periodontitis with a Periapical Index (PAI) score of at least 3.
- Root canal filling material considered completely removable by nonsurgical means.
- Sufficient coronal tooth structure to allow rubber dam isolation.
Key exclusion criteria (8 listed)
- Antibiotic use within the preceding 3 months.
- Pregnancy or breastfeeding.
- American Society of Anesthesiologists physical status classification II or higher.
- Periodontal probing depth greater than 4 mm in the study tooth.
- Root fracture, perforation, or root resorption in the study tooth.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Photon-Induced Photoacoustic StreamingAlso: PIPSAfter S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia) in PIPS mode at 20 mJ, 15 Hz, 0.3 W and 50-microsecond pulse duration, with water and air spray off. A tapered PIPS 600/9 tip (600 micrometers, 9 mm) will be held stationary in the access cavity above the canal orifice without insertion into the canal. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout. | Device | PIPS Laser-Activated Irrigation |
| Shock Wave Enhanced Emission Photoacoustic StreamingAlso: SWEEPSAfter S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with an Er:YAG laser (2940 nm; LightWalker ST-E Pro, Fotona d.o.o., Ljubljana, Slovenia) in AutoSWEEPS mode at 20 mJ, 15 Hz and 0.3 W, with water and air spray off. A Radial SWEEPS 600/9 tip (600 micrometers, 9 mm) will be held stationary in the access cavity above the canal orifice without insertion into the canal. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout. | Device | SWEEPS Laser-Activated Irrigation |
| Passive Ultrasonic IrrigationAlso: PUIAfter S2 sampling, 3 mL of 17% EDTA will be delivered with the needle 2 mm short of the working length and left for 3 minutes without activation, then aspirated, and the canal will be rinsed with 5 mL of sterile saline. The canal and pulp chamber will be filled with 2 mL of 5% NaOCl and activated for 20 seconds with a Woodpecker DTE S6 ultrasonic device (Guilin Woodpecker Medical Instrument Co., Ltd., Guilin, China) and an ED60 tip in Endo mode at power level 2. The tip will be positioned 2 mm short of the working length and activated without contacting the root canal walls. This will be repeated three times with fresh 2 mL of NaOCl (total 6 mL, 60 seconds of activation), keeping the pulp chamber filled throughout. | Device | Passive Ultrasonic Irrigation |
Primary outcome
Reduction in Viable Total Cultivable Intracanal Bacterial Load From S2 to S3
Time frame: Day 1 (During the single treatment visit, from completion of chemomechanical preparation (S2) to immediately after final irrigant activation (S3).)
Viable total cultivable intracanal bacteria will be quantified by culture as colony-forming units per milliliter (CFU/mL). For each participant, the reduction will be calculated as log10 CFU/mL at S2 minus log10 CFU/mL at S3 and reported in log10 CFU/mL. The reduction will be compared among the PIPS, SWEEPS and passive ultrasonic irrigation groups. S1 denotes sampling after removal of the root canal filling material and before chemomechanical preparation; S2, after chemomechanical preparation and before final irrigant activation; S3, immediately after final irrigant activation.
6 secondary outcomes
Reduction in Viable Total Cultivable Intracanal Bacterial Load From S1 to S2
Time frame: Day 1 (During the single treatment visit, from root canal filling removal (S1) to completion of chemomechanical preparation (S2).)
Overall Reduction in Viable Total Cultivable Intracanal Bacterial Load From S1 to S3
Time frame: Day 1 (During the single treatment visit, from root canal filling removal (S1) to immediately after final irrigant activation (S3).)
Reduction in Viable Intracanal Enterococcus faecalis Load From S1 to S2
Time frame: Day 1 (During the single treatment visit, from root canal filling removal (S1) to completion of chemomechanical preparation (S2).)
Reduction in Viable Intracanal Enterococcus faecalis Load From S2 to S3
Time frame: Day 1 (During the single treatment visit, from completion of chemomechanical preparation (S2) to immediately after final irrigant activation (S3).)
Overall Reduction in Viable Intracanal Enterococcus faecalis Load From S1 to S3
Time frame: Day 1 (During the single treatment visit, from root canal filling removal (S1) to immediately after final irrigant activation (S3).)
Percentage of Participants With Culture-Positive Enterococcus faecalis After Final Irrigant Activation (S3)
Time frame: Day 1 (Immediately after final irrigant activation (S3), during the single treatment visit.)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
- Results publication: PubMed 38340037Meire M, De Moor RJG. Principle and antimicrobial efficacy of laser-activated irrigation: A narrative review. Int Endod J. 2024 Jul;57(7):841-860. doi: 10.1111/iej.14042. Epub 2024 Feb 10.
- Results publication: PubMed 34714548Siqueira JF Jr, Rocas IN. A critical analysis of research methods and experimental models to study the root canal microbiome. Int Endod J. 2022 Mar;55 Suppl 1:46-71. doi: 10.1111/iej.13656. Epub 2021 Nov 16.
- Results publication: PubMed 33353920Barbosa-Ribeiro M, Arruda-Vasconcelos R, Mendes Louzada L, Rodrigues Lima A, Marciano M, Affonso de Almeida JF, De-Jesus-Soares A, Zaia AA, Ferraz C, Gomes BP. Microbiological Investigation in Teeth with Persistent/Secondary Endodontic Infection in Different Stages of Root Canal Retreatment. Eur Endod J. 2020 Dec;5(3):219-225. doi: 10.14744/eej.2020.73626.
- Results publication: PubMed 39012553Hepsenoglu YE, Ersahan S, Erkan E, Gundogar M, Ozcelik F. Is SWEEPS better than PUI in reducing intracanal bacteria and inflammation in cases of apical periodontitis? Lasers Med Sci. 2024 Jul 16;39(1):182. doi: 10.1007/s10103-024-04117-9.
- Individual participant dataSharing planned: No. Individual participant data will not be made publicly available because participants' informed consent and the ethics committee approval do not cover data sharing with third parties. Aggregated results will be reported in the publication. De-identified data may be made available by the corresponding author upon reasonable request, subject to approval by the institutional ethics committee.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Elçin Tekin Bulut, DDS, PhD principal investigator
Inonu University, Faculty of Dentistry, Department of Endodontics
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Photon-Induced Photoacoustic Streaming, Shock Wave Enhanced Emission Photoacoustic Streaming and Passive Ultrasonic Irrigation in people with Apical Periodontitis, run by Inonu University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ebru Özcan, DDS (+90 536 706 79 25, ebru_ozcan@inonu.edu.tr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Reduction in Viable Total Cultivable Intracanal Bacterial Load From S2 to S3 (time frame: Day 1 (During the single treatment visit, from completion of chemomechanical preparation (S2) to immediately after final irrigant activation (S3).)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07903285, which also lists 4 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.