Histopathological Evaluation of the Periodontal Ligament Subjected to Laser Ablation.

Histopathological Evaluation of the Periodontal Ligament and Cementum of Extracted Teeth Subjected to Laser Ablation With Indocyanine Green.

Laser Ablation therapy (LA) using an 810nm diode laser and Indocyanine Green (ICG) solution, which efficiently absorbs laser energy and increases the effectiveness of tissue removal. Intracanal heating can potentially cause damage to structures outside the tooth root. The study was to observe possible changes in the periodontal ligament and cementum resulting outside the root using this treatment. Histological and morphological examination of extracted cementum, ligament, and collagen post-exposure showed no difference in these structures vs. non-treated controls.

Study Overview

• Status: Completed
• Conditions: Pulp Necroses
• Intervention / Treatment: Device: Laser and ICG solution.

Detailed Description

Laser Ablation therapy (LA) using 810nm diode laser and Indocyanine Green (ICG) solution which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Intracanal heating can potentially cause damage to cementum structure and periodontal tissues. The objective of this study is to observe possible changes in the periodontal ligament and cementum resulting from the use of LA with ICG as an adjuvant therapy to endodontic treatment. Ten patients with lower incisors requiring extraction will be selected. Before extraction, chemical-mechanical root canal preparation will be carried out with a single file reciprocating system (35/04) and 2.5% sodium hypochlorite solution. Then, the canals will be dried and filled with 0.05% ICG, which will remain in place for 1 minute (pre-irradiation time). For the test group, a #20 laser fiber will be inserted into the root canal to the working length. The 810 nm wavelength infrared diode laser is activated with a power of 2.5W, an interval of 300 ms, and a duration of 100 ms. After activation commences, circular movements are made for a period of 30 seconds together with the fiber removal movement. After the first activation, there is a 30-second pause and a new 30-second activation cycle will then be performed in the same way as the previous one. After treatment, the tooth element will be extracted and the apical third of the root with the periodontal ligament is processed for histological analysis using hematoxylin-eosin and picrosirius red staining to evaluate the morphological structures. Two teeth extracted without treatment will be used as controls.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • Parana
    • Maringá, Parana, Brazil, 87050-900
      • Unicesumar Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age 18 years or older.
• Requiring at a least one mandibular incisor to be extracted.

Exclusion Criteria:

• Evidence of periodontal disease anywhere in the mouth beyond the apical third of any tooth.
• Mandibular canines that do not require extraction.
• Presence of other dental or oral conditions of any type that require immediate intervention.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: All Study Participants.; Single study group that requires extraction of mandibular incisors for other reasons. Teeth are accessed, subject to filing, pulp extirpation, and treated with endodontic solutions. Some teeth of the participants are then subject to study intervention consisting of an ICG solution into the root followed by laser exposure of the solution in situ. After laser exposure, the pulp chamber and roots are rinsed then mechanically extracted. Other teeth of some participants will not be subject to the ICG and laser intervention, but will proceed to the final rinse and extraction. After extraction, specimens are fixed, stained, and mounted for visual examination under a microscope. Images of tissue are captured for documentation. Samples are examined for histological and morphological condition of the periodontal ligament, cementum, and collagen attached to the external surface of the extracted tooth root.

Device: Laser and ICG solution.; Intervention consists of addition of a combined laser absorption solution and infrared diode laser. The solution is introduced into the prepared pulp chamber and root canals, allowed to dwell for 1 minute, followed by exposure to the laser energy delivered via a fiber optic introduced into the root canal, and while activating the laser at 2.5 watts of optical output with a pulse duration of 100 msec and a pulse gap of 300 msec, the solution and residual structures in the root and pulp chamber are exposure over the course of 30 seconds, moving and relocating the fiber tip throughout the canals and chamber during that time. The laser is halted and a wait time of 30 seconds is applied. The laser fiber is then reintroduced and another 30 second exposure, repeating the same settings and technique.; Other Names: Leonardo Diode Laser and LEAP Laser Absorption Solution

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cell Count of Inflammatory Infiltrate Per Cross-Sectional Area at 400X Magnification	Count the number of inflammatory cells within a cross-sectional area viewed under 400X magnification, comparing the difference in the quantity of inflamed cells reacting to injury to the tissues resulting from the investigational treatment, as compared a count of inflamed cells reacting to the control treatment.	28 days after intervention.
Gap Distance of Inflammatory Resorption Between Inflamed Tissue and Root Surface	Measurement of the gap between the edge of the inflamed tissue and the root surface, measured in microns using computer software to measure the gap of magnified tissue samples, comparing samples from teeth treated with the intervention compared to teeth receiving the control treatment.	28 days after intervention.
Mean Ligament Thickness of the Periodontal Ligament	Measurement of the thickness of the periodontal ligament, measured in microns using computer software to measure the thickness of periodontal ligament within the magnified tissue samples, comparing samples from teeth treated with the intervention compared to teeth receiving the control treatment.	28 days after intervention.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gap Distance of Inflammatory Resorption Between Cementum and Alveolar Bone	Measurement of the gap between the edge of the tooth cementum and the adjacent alveolar bone, measured in microns using computer software to measure the gap of magnified tissue samples, comparing samples from teeth treated with the intervention compared to teeth receiving the control treatment.	28 days after intervention.

Collaborators and Investigators

• Sponsor: CAO Group, Inc.
• Collaborators: Sao Paulo State University, School of Dentistry at Aracatuba, Sao Paulo, Brazil

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2023
• Primary Completion (Actual): October 23, 2023
• Study Completion (Actual): October 31, 2023

Study Registration Dates

• First Submitted: November 16, 2023
• First Submitted That Met QC Criteria: December 7, 2023
• First Posted (Actual): December 18, 2023

Study Record Updates

• Last Update Posted (Estimated): February 29, 2024
• Last Update Submitted That Met QC Criteria: February 27, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Stomatognathic Diseases; Tooth Diseases; Dental Pulp Diseases; Necrosis; Dental Pulp Necrosis; Pharmaceutical Solutions
• Other Study ID Numbers: 70009423.2.0000.5539

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes