Pulp Necroses
Conditions
Brief summary
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.
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.
Interventions
DEVICELaser 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.
Sponsors
São Paulo State University
CAO Group, Inc.
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Masking description
Blinding occurred when analyzing the histological and morphological results. Blinded assessor provided a rating of the samples on an individual basis, not knowing if the sample was from a treated or control tooth.
Intervention model description
Single study group requiring extraction of mandibular incisors for other reasons. Controls selected from among the extraction candidates were not subject to exposure to the laser and ICG solution, but to all other aspects of the pulpectomy procedure. Remaining teeth had the laser and ICG exposure added to the treatment regimen. Treated and control specimens then extracted, prepared, stained, and examined for histological morphological condition of the periodontal ligament, cementum, and collagen attached to the external surface of the extracted tooth root.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cell Count of Inflammatory Infiltrate Per Cross-Sectional Area at 400X Magnification | 28 days after intervention. | 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. |
| Gap Distance of Inflammatory Resorption Between Inflamed Tissue and Root Surface | 28 days after intervention. | 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. |
| Mean Ligament Thickness of the Periodontal Ligament | 28 days after intervention. | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Gap Distance of Inflammatory Resorption Between Cementum and Alveolar Bone | 28 days after intervention. | 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. |
Countries
Brazil
Participant flow
Pre-assignment details
There were no issues with participant wash-out after initial acceptance into the study.
Participants by arm
| Arm | Count |
|---|---|
| Teeth Exposed to Laser and ICG Solution. Single study group that requires extraction of mandibular incisors for other reasons. Teeth will be accessed, subject to mechanical file, pulp extirpation, and treated with endodontic solutions. Teeth will then be exposed to the ICG solution followed by laser exposure of the ICG solution in situ. After laser exposure, the pulp chamber and roots will be rinsed and then the tooth mechanically extracted. After extraction, tissue specimens will be prepared of the root portion of the extracted tooth, fixed, stained, and mounted for visual examination under a microscope. Images of the microscopic images will be captured for documentation. The samples will be examined for the histological and morphological condition of the periodontal ligament, cementum, and collagen attached to the external surface of the extracted tooth root. These tissue types were graded based on the extent of damage or destruction observed.
Laser and ICG solution.: Intervention consists of addition of laser absorption solution and infrared diode laser. The solution is introduced into pulp chamber and root canals, dwells for 1 minute, followed by exposure to the laser delivered via optical fiber introduced into the root canal, activating the laser at 2.5W optical output, pulse duration of 100msec and pulse gap of 300msec, with laser emissions totaling 30s, moving and relocating the fiber during the exposure. The laser is halted, a 30s wait, then solution and laser is repeated. | 10 |
| Teeth Exposed to Laser and ICG Solution. Single study group that requires extraction of mandibular incisors for other reasons. Teeth will be accessed, subject to mechanical file, pulp extirpation, and treated with endodontic solutions. Teeth will then be exposed to the ICG solution followed by laser exposure of the ICG solution in situ. After laser exposure, the pulp chamber and roots will be rinsed and then the tooth mechanically extracted. After extraction, tissue specimens will be prepared of the root portion of the extracted tooth, fixed, stained, and mounted for visual examination under a microscope. Images of the microscopic images will be captured for documentation. The samples will be examined for the histological and morphological condition of the periodontal ligament, cementum, and collagen attached to the external surface of the extracted tooth root. These tissue types were graded based on the extent of damage or destruction observed.
Laser and ICG solution.: Intervention consists of addition of laser absorption solution and infrared diode laser. The solution is introduced into pulp chamber and root canals, dwells for 1 minute, followed by exposure to the laser delivered via optical fiber introduced into the root canal, activating the laser at 2.5W optical output, pulse duration of 100msec and pulse gap of 300msec, with laser emissions totaling 30s, moving and relocating the fiber during the exposure. The laser is halted, a 30s wait, then solution and laser is repeated. | 12 |
| Total | 22 |
Baseline characteristics
| Characteristic | Teeth Exposed to Laser and ICG Solution. |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 10 Participants |
| Region of Enrollment Brazil | 10 participants |
| Sex: Female, Male Female | 6 Participants |
| Sex: Female, Male Male | 4 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 12 | 0 / 2 |
| other Total, other adverse events | 0 / 10 | 0 / 2 |
| serious Total, serious adverse events | 0 / 10 | 0 / 2 |
Outcome results
Primary
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.
Time frame: 28 days after intervention.
Population: Mandibular incisor teeth
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Teeth Exposed to Laser and ICG Solution. | Cell Count of Inflammatory Infiltrate Per Cross-Sectional Area at 400X Magnification | Intervention | 10.3 Cells / 0.1 mm^2 | Standard Deviation 1.79 |
| Teeth Exposed to Laser and ICG Solution. | Cell Count of Inflammatory Infiltrate Per Cross-Sectional Area at 400X Magnification | Control | 10.5 Cells / 0.1 mm^2 | Standard Deviation 0.2 |
Primary
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.
Time frame: 28 days after intervention.
Population: Mandibular incisor teeth
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Teeth Exposed to Laser and ICG Solution. | Gap Distance of Inflammatory Resorption Between Inflamed Tissue and Root Surface | Intervention | 0 micrometer | Standard Deviation 0 |
| Teeth Exposed to Laser and ICG Solution. | Gap Distance of Inflammatory Resorption Between Inflamed Tissue and Root Surface | Control | 0 micrometer | Standard Deviation 0 |
Primary
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.
Time frame: 28 days after intervention.
Population: Mandibular incisor teeth
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Teeth Exposed to Laser and ICG Solution. | Mean Ligament Thickness of the Periodontal Ligament | Intervention | 173.55 micrometer | Standard Deviation 14.33 |
| Teeth Exposed to Laser and ICG Solution. | Mean Ligament Thickness of the Periodontal Ligament | Control | 178.8 micrometer | Standard Deviation 6.66 |
Secondary
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.
Time frame: 28 days after intervention.
Population: Mandibular incisor teeth
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Teeth Exposed to Laser and ICG Solution. | Gap Distance of Inflammatory Resorption Between Cementum and Alveolar Bone | Intervention | 0 micrometer | Standard Deviation 0 |
| Teeth Exposed to Laser and ICG Solution. | Gap Distance of Inflammatory Resorption Between Cementum and Alveolar Bone | Control | 0 micrometer | Standard Deviation 0 |