Efficacy of 810 nm Diode Laser Disinfection on Inflammatory Cytokines and Postoperative Pain After Endodontic Retreatment

NCT07141459 | Recruiting DMC

• 1 other identifier: P-PD-25-26
• Study Type: interventional
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

The main cause of endodontic disorders is microbial infection. From the infected pulp tissue, microorganisms can penetrate into the deeper layers of root dentine and propagate a periapical tissue through the apical foramen and lateral canals causing apical periodontitis. Apical periodontitis is an inflammatory condition affecting the periapical area of teeth with a global prevalence of 52% among individuals and 5% at tooth level. At the periapical region, microbes and their products encounter the host immune defense. Innate immune cells combat bacteria through phagocytosis and release anti-microbial substances, while adaptive immune cells initiate both cell-mediated and humoral immune responses. This immune activation also stimulates osteoclasts, leading to bone resorption and creating space for the inflammatory cells' infiltration. During pulpal and periapical inflammation, neutrophils are the predominant immune cells that migrate to the affected area. The main molecules involved in guiding and activating these neutrophils to the site of infection is interleukin-8 (IL-8). This cytokine is locally produced at the site of inflammation and has been linked to pulpal breakdown and apical periodontitis. It promotes the release of tissue-destructive enzymes by neutrophil degranulation. In addition, it affects other leukocyte types such as T cells, B cells, IL-2 activated natural killer cells, and basophils. It has been shown that IL-8 expression is closely related to both infection and inflammation. IL-1β stimulates destruction of periapical tissues which appears to be strongly linked to high microbial load present within the root canal system. It has been identified in teeth exhibiting periapical lesions and root canals containing exudate. Particularly, high levels of IL-1β appear to be related to the presence of clinical signs/ symptoms and destruction of periapical bone Eliminating microorganisms is the primary objective of root canal therapy in order to create an environment as free of bacteria as possible. However, not all root canal treatments are completely successful, and in some cases, the infection persists leading to development of secondary apical periodontitis in previously treated teeth. Disinfecting the root canal during retreatment is significantly more challenging due to the presence of persistent microorganisms that have settled in the root canal system. These microbes are often resistant to standard irrigations and antimicrobial agents leading to the formation of periradicular lesions. Such bacteria can survive for extended periods around the previously filled root canals. Sodium hypochlorite (NaOCl) is the most widely used irrigant in root canal therapy due to its strong antibacterial effect and its ability to dissolve organic substances. Effective canal cleaning is difficult to achieve without the use of NaOCl at a sufficiently high concentration. However, NaOCl has several drawbacks, including its cytotoxicity which can lead to tissue damage and patient symptoms. Additionally, its strong oxidizing nature negatively affects the mechanical properties of dentin such as microhardness and elastic modulus. NaOCl should be used with caution in endodontic procedures to prevent hypochlorite accidents. Calcium hydroxide (Ca (OH)2) is the most widely utilized intracanal medication. It has the potential to dissolve tissue, acts as a physical barrier and generates hydroxyl ions, creating an extremely alkaline environment. It has been shown to be quite effective in the treatment of teeth with persistent periapical lesions. To provide optimal endodontic treatment, the root canal system should be thoroughly cleaned of soft-tissue debris, smear layer, and bacteria. However, it is impossible to completely disinfect and clean debris that build up. That is why, adjunctive aids, such as the use of passive ultrasonic and sonic activation of the irrigant and lasers with varying wave lengths, have been introduced during conventional endodontic therapy in cleaning maneuvers. Laser therapy for root canal disinfection has gained popularity since laser-assisted root canal treatment aims to remove the smear layer, penetrate deep into dentin and eliminate bacteria up to 1000 μm . Laser types have been shown to reduce bacterial load when used as an adjunct to conventional root canal treatment such as Nd:YAG , Er:YAG and diode laser .

Conditions

Previous Endodontic Treatment Failure and Radiographically Confirmed Periapical Radiolucency

Keywords

810 nm diode laser; inflammatory cytokines

Outcome Measures

Primary Outcomes (1)

• IL-8 and IL-1β expression

  IL-8 and IL-1β levels will be quantified using ELISA kit according to manufacturer instructions

  1week

Secondary Outcomes (1)

• Postoperative pain assessment

  • Pre-treatment (baseline). • 6 hours post-treatment. • 12 hours post-treatment. • 1st day post-treatment. • 2nd day post-treatment. • 3rd day post-treatment. • 7th day post-treatment.

Study Arms (2)

Group I (Diode laser group)

EXPERIMENTAL

Laser activated disinfection will be performed using 810 nm diode laser (Elexxion clarosdental laser, Singen Deutschland, Germany) in a continuous wave mode with a power of 1.5 Watts in 4 cycles of 5 seconds with 20 seconds intervals in between each. Prior to irradiation, all the individuals in the room will wear protective laser safety eye glasses. A 200 μm fiber optic tip (Lite medics, Italy) will be inserted 1 mm from the working length, activated and moved in slow helical motion from the apex to the cervical third with alternating between clockwise and counterclockwise direction at speed of about 2 mm/s(30). 5 ml saline solution will be used for each application and finally before taking post-irradiation sample (S3) using #40 paper points. The teeth will be restored with light cure glass ionomer resin cement temporarily. Finally, the root canal system will be obturated using ADSEAL resin-based sealer (Meta Biomed Co, Cheongju, Korea) and gutta-percha.

Device: 810 nm diode laser disinfection

Group II (Calcium hydroxide group)

EXPERIMENTAL

Calcium hydroxide paste (MetaBiomed, Chungcheongbuk-do, Korea) will be placed inside the root canal and left for 1 week. The access cavity will be temporarily sealed with light cure glass ionomer resin cement. After 1 week, the temporary filling will be removed following local anaesthesia and isolation, the root canal will be irrigated with 20 ml saline and gently filed using H file corresponding to the master apical file size. The last sample (S3) will be collected using #40 paper points. Root canal obturation and final coronal restoration will be completed as in group I

Drug: Calcium Hydroxide Intracanal medication

Interventions

810 nm diode laser disinfection DEVICE

810 nm diode laser (Elexxion clarosdental laser, Singen Deutschland, Germany) in a continuous wave mode with a power of 1.5 Watts in 4 cycles of 5 seconds with 20 seconds intervals in between each. A 200 μm fiber optic tip (Lite medics, Italy) will be inserted 1 mm from the working length, activated and moved in slow helical motion from the apex to the cervical third with alternating between clockwise and counterclockwise direction at speed of about 2 mm/s

Group I (Diode laser group)

Calcium Hydroxide Intracanal medication DRUG

Calcium hydroxide paste (MetaBiomed, Chungcheongbuk-do, Korea) will be placed inside the root canal and left for 1 week.

Group II (Calcium hydroxide group)

Eligibility Criteria

• Age: 20 Years - 40 Years
• Gender Eligibility Details: cytokine levels varies greatly depending on gender
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Patients have single-rooted teeth with root canal form type I.
• Have previous endodontic therapy with failure.
• Have periapical radiolucency (PAI score of 3 or 4).
• Asymptomatic patients who had no pain or swelling had a negative response to palpation and percussion.
• Patients who provide written informed consent.

You may not qualify if:

• Patients who had received antibiotic therapy within the past 3 months. Pregnancy and lactation.
• Systemic disease.
• Physical or mental disability.
• Non restorable teeth.
• Any signs of resorption, immature roots, fracture, sinus tract and dental anomaly

Sponsors & Collaborators

• Al-Azhar University: lead

Study Sites (1)

from the outpatient clinic of Endodontic Department, Faculty of Dental Medicine for Girls, Al-Azhar University

Cairo, Egypt

RECRUITING

Related Publications (3)

• Morsy DA, Shaker OG, ElKhodary SA. Effect of diode laser (980 nm) on IL-8 expression in failed endodontic cases: Randomised control trial. Aust Endod J. 2025 Apr;51(1):17-25. doi: 10.1111/aej.12914. Epub 2024 Dec 10.

  PMID: 39659152 BACKGROUND

• Ozlek E, Kadi G, Shoshaa N, Saed Y, Meydan I. Interleukin-8 (IL-8) levels in gingival crevicular fluid during root canal treatment of molar teeth with symptomatic irreversible pulpitis: impact of varying sodium hypochlorite concentrations. BMC Oral Health. 2024 Mar 27;24(1):392. doi: 10.1186/s12903-024-04128-6.

  PMID: 38539133 BACKGROUND

• Tiburcio-Machado CS, Michelon C, Zanatta FB, Gomes MS, Marin JA, Bier CA. The global prevalence of apical periodontitis: a systematic review and meta-analysis. Int Endod J. 2021 May;54(5):712-735. doi: 10.1111/iej.13467. Epub 2021 Jan 22.

  PMID: 33378579 BACKGROUND

Central Study Contacts

Sabah M. Sobhy, PHD

CONTACT

01096529143; sabamorad@yahoo.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: statician
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Endodontic department, al azhar university. principal investigator

Study Record Dates

• First Submitted: August 19, 2025
• First Posted: August 26, 2025
• Study Start: August 18, 2025
• Primary Completion (Estimated): September 15, 2026
• Study Completion (Estimated): October 20, 2026
• Last Updated: September 4, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

EG (1)