Low-level laser therapy as an alternative for pulpotomy in human primary teeth

The application of lasers in vital pulp therapy: a review of histological effects

Vital pulp therapy (VPT) is primarily intended to preserve the vitality of pulp tissues, which have been exposed for any reason. Various materials and techniques have been proposed to improve treatment outcomes, including the use of lasers. This study aimed to review the histological results of different dental lasers including low-level lasers, carbon dioxide (CO2), erbium-doped yttrium aluminum garnet laser (Er:YAG), neodymium-doped yttrium aluminum garnet (Nd:YAG), erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers, and diode lasers for VPT. This focused review included a comprehensive electronic search of Scopus, MEDLINE, Web of Science, and Google Scholar databases from 2000 to 2022 by two independent investigators. Different combinations of keywords were used, and reference mining of related papers was done. The review included studies related to histologic evaluation of laser-assisted vital pulp therapy that stated the laser parameters that were used. Articles with radiographic or clinical assessments or articles lacking necessary data were excluded. Non-English articles were excluded unless their abstract was in English and encompassed the necessary data. Most studies indicated the efficacy of lasers for reduction of inflammation, acceleration of healing, and increasing the thickness of dentinal bridge. According to the evidence, lasers used in combination with pulp capping agents are beneficial to enhance the success rate of VPT.

Dentists' Self-evaluated Ability in Diagnosing and Updating About Pulpotomy

OBJECTIVE

This study aimed to self-evaluate the knowledge of different dental professionals' profiles in Brazil on diagnosing and indicating pulpotomy in primary teeth and how these groups updated on this theme.

METHODS

Three groups (G1: professors, G2: specialists, and G3: professionals) answered an online questionnaire containing 20 questions and returned 416 questionnaires. Data were subjected to Chi-square associative tests and t tests, with P < .05.

RESULTS

G1 and G2 reported to indicate pulpotomy, highlighting the tendency of these groups towards seeking updates on this subject. All 3 groups used academic materials for updating. However, G2 had a high demand for updates through congresses, whilst G3 had a high demand for updates through social media (Google and Google Scholar). The most cited indication by G1 and G2 was "accidental pulp exposure" and by G3 was "teeth with extensive carious lesions that have involved the pulp with radiographic confirmation." All 3 groups opted for pulpotomy to keep the tooth in the arch. Thus, G1 and G2 are the groups who are more updated on the subject, using mainly academic materials, which can be associated with the fact that such groups indicated pulpotomy in primary teeth. The lower interest in searching about pulpotomy in G3 can be understood as a nonclinical application of the topic for this group.

CONCLUSIONS

Professionals who work directly with paediatric dentistry (professors or specialists) felt more capable of diagnosing and treating cases of pulpotomy. In addition, most of the professionals used scientifically based sources for getting information and actualisation on the subject of pulp therapies.

The comparison of calcium hydroxide + biostimulation, calcium hydroxide, formocresol, and MTA pulpotomies without biostimulation in primary teeth: 12-months clinical and radiographic follow-up

This study has aimed to evaluate the clinical and radiographic success rates of calcium hydroxide pulpotomy (CH) with biostimulation (PBMT) and compare them to that of CH, formocresol (FC), mineral trioxide aggregate (MTA) pulpotomies without PBMT in primary molars. A total of 172 pulpotomies were performed on primary first or second mandibular molars in 94 children who were 5-8 years old. The pulpotomy procedure was performed with four different techniques. In the PBMT group, before the CH placement, 820-nm diode laser radiation was applied to each pulp-stump for 12 s (10 mW, 2.5 J/cm²). The clinical (lack of spontaneous pain, abscess or fistula, and pathological mobility) and radiographic success (lack of periapical/furcal lesions and internal/external resorption) were recorded at 6 and 12 months. The data was statistically evaluated. p value < 0.05 was considered as significant. After 12 months, the clinical and radiographic success rate (a tooth with at least one of the findings was considered unsuccessful) was 97%/92% for FC and 97%/95%, 87%/73%, and 71%/45% for MTA, CH + PBMT, and CH, respectively. There was no significant difference between the CH + PBMT and the other groups in clinical success, while a significant difference was found between CH and FC, MTA groups. In radiographic success, there was a significant difference between the CH and the other groups. No significant difference was found between the 6th- and 12th-month results in clinical success for all the groups. A decrease in success over time was seen only in the CH group for radiographic results. CH without PBMT showed the worst clinical and radiographic results among the groups. CH + PBMT showed similar clinical success compared to the MTA and FC groups. In radiographic success, CH + PBMT showed higher success compared to CH, but this success was not high as compared to MTA and FC.

Clinical and radiographic effectiveness of mineral trioxide aggregate (MTA) partial pulpotomy with low power or high power diode laser irradiation in deciduous molars: a randomized clinical trial

This study investigated the clinical and radiographic effectiveness of MTA partial pulpotomy with low power or high power diode laser irradiation in primary molars. In this randomized single-blind clinical trial, 63 mandibular second molars were assigned into three groups (n = 21). After pulp amputation and achieving hemostasis, MTA was placed over pulp stumps in group 1 (MTA). The patients in groups 2 (LLLT-MTA) and 3 (DL-MTA) underwent low level (660 nm, 200 mW) and high power (810 nm, 1 W) diode laser radiation prior to MTA placement, respectively. The occurrence of clinical failure (spontaneous pain, tenderness upon percussion, swelling, fistula, mobility) and radiographic failure (periodontal ligament widening, external or internal root resorption, periapical or furcal radiolucency) was recorded up to 18 months after therapy. MTA and LLLT-MTA groups showed clinical success rate of 100% throughout the experiment. The clinical success rate of DL-MTA group was 95.2%, 95.2%, and 87.5% after 6, 9, and 18 months. The radiographic success rates were 90.5%, 90.5%, and 87.5% in the MTA group; 100%, 95.2%, and 88.2% in the LLLT-MTA group, and 85.7%, 76.2%, and 68.7% in the DL-MTA group, at 6-, 9-, and 18-month follow-ups, respectively. No significant differences were found in the frequency of clinical or radiographic failure among the groups at any interval (p > 0.05). MTA partial pulpotomy was a suitable technique for vital pulp therapy in deciduous teeth. The addition of low power or high power diode laser radiation to the procedure did not cause a significant difference in success rate values.

Efficacy of Mineral Trioxide Aggregate and Photobiomodulation on Pulp Capping of Dogs’ Teeth

AIM: The present study assessed the effect of mineral trioxide aggregate (MTA) and photobiomodulation (PBM) on pulp capping of exposed pulp of dogs’ teeth. METHODS: Forty-eight teeth in three mongrel dogs were randomly divided into two major study groups; Group I where MTA was used as a pulp capping agent and Group II in which both MTA+PBM were used. The groups were equally subdivided according to the observation period following completion of pulp capping into Subgroup (A) 1 week, Subgroup (B) 2, and Subgroup (C) 16 weeks. The teeth were examined for histological inflammatory response as well as dentine bridge formation. RESULTS: With regard to inflammatory response at 1 week significantly, less intense inflammation was observed in MTA+PBM (Group II) compared to the MTA (Group I) for the same time period with no significant difference for between Group I and Group II for other time intervals. As for dentin bridge formation, PBM+MTA groups showed statistically significant thicker dentine bridge formation at 16 weeks than MTA alone group for the same time period with no significant difference for between Group I and Group II for other time intervals. CONCLUSIONS: Under the conditions of this study, PBM appeared to be a beneficial adjunct in dental pulp capping procedures in which MTA was the pulp capping material.

Photobiomodulation reduces inflammation but does not influence the hypoxia-inducible factor-1α in pulp tissue of rats after bleaching

Objectives:

To evaluate the influence of photobiomodulation with infrared laser (IRL) in the rat pulp tissue after bleaching, considering the immunolabeling of interleukin (IL)-23 and hypoxia-inducible factor (HIF)-1α.

Methodology:

The right and left molars of forty rats were divided into groups: Control – with placebo gel and Bleached – with 35% hydrogen peroxide (H₂O₂). Half of the rats received one IRL application on both sides, establishing a split-mouth design, which resulted in 4 groups with 20 hemi-maxillae each: Control, Bleach, IRL, and Bleached-IRL. Rats (n=10) from each group were euthanized, at 2- and 30-days mark, and the pulp tissue was evaluated using inflammation and immunolabeling scores. Wilcoxon and Mann-Whitney statistical tests were performed (p<0.05).

Results:

At the 2-days mark, the Bleached group had severe inflammation and necrosis in the occlusal thirds of the pulp, and moderate to severe inflammation in cervical third, whereas the Bleached-IRL had mild to moderate inflammation (p<0.05). At the 30-days mark, there was no inflammation, but tertiary dentine formation in the bleached groups. Regarding IL-23, severe immunolabeling was observed in the Bleached group (p<0.05) at the 2-days mark; at the 30-days mark, there was a reduction in immunolabeling, in which the Bleached group had moderate and the Bleached-IRL group had mild immunolabeling (p>0.05). HIF-1α was more evident at the 2-days mark in the Bleached group, without significant difference with the Bleached-IRL (p>0.05). The difference was observed between the bleached and control groups, without immunolabeling (p<0.05); at the 30-days mark, the Bleached group had reduction in HIF-1α immunolabeling, while the Bleached-IRL had an increase; the difference remained between the bleached and the controls groups (p<0.05)

Conclusion:

Photobiomodulation using IRL minimized the inflammation and IL-23 immunolabeling in the pulp tissue of rats after dental bleaching, but did not influence significantly the HIF-1α immunolabeling.

Efficacy of laser photobiomodulation pulpotomy in human primary teeth: A randomized controlled trial

BACKGROUND

Laser photobiomodulation (LPBM), also called Low Level Laser Therapy (LLLT), has shown potential to reduce the pulpal inflammation and to preserve the dental pulp vitality, thereby improving healing. Lasers being minimally invasive, safe, and patient friendly prompt its application in pediatric dentistry.

AIM

The aim of this study was to evaluate and compare the clinical and radiographic success rates of LPBM and formocresol pulpotomy at 9 months post intervention in human primary molars.

MATERIALS AND METHODS

A randomized controlled, split-mouth study design was followed involving children aged 4-7 years with at least two primary molars indicated for pulpotomy. Sixty-eight eligible primary molars were randomly allocated to two interventions - formocresol pulpotomy (Group I) and LPBM pulpotomy (Group II).

STATISTICAL ANALYSES

Chi-square test was used for statistical analysis fixing significance level at P ≤ 0.05.

RESULTS

There was no statistically significant difference in the clinical success rates between the formocresol group (97.05%) and the photobiomodulation group (94.1%) (χ² = 0.34, P = 0.55); however, the radiographic success rate was significantly high in the laser group (94.1%) compared to the formocresol group (58.82%) (χ² = 11.76, P = 0.001).

CONCLUSION

LPBM could be a viable nonpharmaceutical alternative for formocresol pulpotomy in human primary teeth.

Evaluation of the bond strengths of restorative materials to primary tooth dentin treated with different pulpotomy techniques

The aim of this study was to investigate the changes of different pulpotomy techniques on the primary tooth dentin and to evaluate the effects of these pulpotomy methods on the shear bond strength of restorative materials to primary tooth dentin. Two hundred and forty dentin specimens were distributed randomly to the study groups as; control, ferric sulphate, Biodentine® , Nd:YAG laser, photobiomodulation, and atmospheric pressure cold plasma (APCP). After the application of pulpotomy methods, samples were again randomly divided to two restorative materials (glass hybrid and composite resin) (n = 20) and shear bond strength (SBS) test was performed. Then, 12 new dentin specimens were prepared for all groups for surface analysis. Surface examination (n = 12) and fracture analyses (n = 240) were carried out with scanning electron microscope (SEM). Statistical significance range was accepted as α <.05 for all data. A statistically significant difference was obtained among all study groups for glass hybrid material as well as composite material (p <.05). While the highest mean SBS value was obtained with Nd:YAG laser (7.58 ± 0.60 MPa), the lowest value was observed with Biodentine® (6.70 ± 0.91 MPa; p = .001) for glass hybrid material. For composite material, the highest mean SBS value was calculated for Nd:YAG laser (13.79 ± 1.24 MPa), while the lowest value was obtained with ferric sulphate (10.17 ± 1.45 MPa; p = .001). Fracture modes were mainly adhesive and mixed type according to SEM analysis. Moreover, morphological changes were observed with SEM on the dentin surfaces of ferric sulphate, Biodentine® and Nd:YAG laser. Within the limitations of this study, Nd:YAG laser increased the shear bond strength values in groups of composite resin. RESEARCH HIGHLIGHTS: In this article, we report the results of the shear bonding strength test of two restorative materials (glass-hybrid vs. composite resin) to primary tooth dentin following the application of five different pulpotomy techniques (ferric sulfate, Biodentine® , Nd:YAG laser, photobiomodulation, and atmospheric pressure cold plasma) were reported. This article will contribute to the literature that there are considerably limited researches concerning the bond strength of glass hybrid to primary dentin and also atmospheric pressure cold plasma in pulpotomies. The SEM examination was performed in two stages in this study; the morphological changes in both treated dentin surfaces and the surfaces of the samples subjected to the shear bond strength test.

Photobiomodulation effect of red LED (630 nm) on the free radical levels produced by pulp cells under stress conditions

The aim of this study was to assess the ability of red light emitting diodes (LED) to modulate oxidative stress in human dental pulp fibroblasts (HDPFs) when different irradiation parameters are employed. Cells from primary teeth were seeded (100,000 cells/well) in 24-well plates in culture medium (DMEM). At 24 h after incubation, the culture medium was replaced with DMEM containing 10 μg/mL lipopolysaccharide (LPS). Thereafter, the cells were irradiated (LED 630 nm, 0.04 W/cm² and 0.08 W/cm²) at 0 J/cm² (control group), 4 J/cm², 15 J/cm², and 30 J/cm²; and their viability (MTT assay), number (Trypan Blue), synthesis of nitric oxide (NO) (Griess reagent), and reactive oxygen species (ROS) (fluorescence probe, DCFH-DA) were assessed. The Kruskal-Wallis and Mann-Whitney statistical tests using Bonferroni correction were employed (significance level of 5%). Compared to that in control fibroblasts, increased viability was observed in HDPFs exposed to LPS and irradiated with 15 J/cm² and 30 J/cm² at 0.04 W/cm² and 4 J/cm² and 15 J/cm² at 0.08 W/cm² (p < 0.05). Exposure to 4 J/cm² at 0.04 W/cm² and 15 J/cm² and 30 J/cm² at 0.08 W/cm² modulated the oxidative stress in cells relative to that observed in non-irradiated LPS-treated pulp cells (p < 0.05). It was concluded that the irradiation strategies of using red LED with radiant exposures of 15 J/cm² and 30 J/cm² at 0.04 W/cm² and 15 J/cm² at 0.08 W/cm² were the best parameters to decrease NO and ROS concentration and to stimulate viability of HDPFs exposed to LPS challenge.

Could the photobiomodulation therapy induce angiogenic growth factors expression from dental pulp cells?

This study aimed to evaluate the effect of different photobiomodulation (PBM) radiant exposures on the viability, proliferation, and gene expression of pulp fibroblasts from human primary teeth (HPF) involved in the pulp tissue repair. HPF were irradiated with Laser InGaAlP (Twin Flex Evolution, MMOptics®) at 660-nm wavelength (red); single time, continuous mode, 0.04-cm² laser tip area, and 0.225-cm laser tip diameter, keeping the distance of 1 mm between the laser beam and the cell culture. The doses used were between 1.2 and 6.2 J/cm² and were evaluated at the 6 h, 12 h, and 24 h after PBM. MTT and crystal violet assays evaluated the cell viability and proliferation. RT-PCR verified VEGF and FGF-2 mRNA expression. A blinded examiner analyzed the data through two-way ANOVA followed by Tukey test (p < 0.05). The groups with higher powers (10 mW, 15 mW, 20 mW, and 25 mW), shortest application periods (10 s), and radiant exposures between 2.5 and 6.2 J/cm² exhibited statistically higher viability than that of the groups with small power (5 mW), longer application period (50 s), and radiant exposure of 6.2 J/cm² (p < 0.05). VEGF and FGF-2 mRNA expression were observed at the three evaluated periods (6 h, 12 h, and 24 h) and the highest expression was in the shortest period (p < 0.05). All radiant exposures maintained HPF viable. The period of 6 h after irradiation showed statistically greater gene expression for both growth factors than other periods. VEGF mRNA had no differences among the dosimetries studied. The best radiant exposures for FGF-2 gene expression were 2.5 J/cm² and 3.7 J/cm².

Pulp repair response after the use of a dentin-pulp biostimulation membrane (BBio) in primary teeth: study protocol for a randomized clinical trial

Background

Vital pulp therapy aims at maintaining the pulp tissue injured but vital. Thus, the use of capping materials that induce tissue regeneration is a great current trend. This study aims to evaluate clinically and radiographically the pulp repair after the use of dentin-pulp biostimulation membrane in primary teeth.

Methods

Four hundred and sixty-eight teeth from children aged between 5 and 9 years old, both genders, with deep caries lesion with pulp involvement, but no furcal impairment and any sign of necrosis will be selected. The vital pulp therapy will be performed with mineral trioxide aggregate (control group) and dentin-pulp biostimulation chitosan membrane (BBio group). The clinical and radiographic outcomes will be assessed at 12 and 24 months after treatment. The thickness of the dentin barrier will be verified through Image J2 software. The Wilcoxon signed rank test and Mann-Whitney test will respectively compare the intra- and intergroup clinical and radiographic outcomes. Paired t test and independent t test will respectively compare the intra- and intergroup radiographic measurements. The logistic regression will be applied, and the degrees of this association will be measured using odds ratio (OR) and 95% confidence interval (95% CI).

Discussion

Therefore, this study protocol aims at new perspectives of vital pulp therapy of primary teeth by employing new easy-handling, low-cost material to keep viable the pulp tissue capable of regenerating and maintain the physiological process of deciduous tooth exfoliation.

Trial registration

Brazilian Registry of Clinical Trials RBR-6vr58b. Registered on 17 February 2019.

Outcome comparison between diode laser pulpotomy and formocresol pulpotomy on human primary molars

Background/purpose

Diode laser is widely used in dentistry, especially on treating soft tissues. Currently neither the effect of diode laser pulpotomy nor its comparison with formocresol (FC) pulpotomy has been fully investigated. Therefore the purpose of this study was to investigate the clinical and radiographic outcomes of diode laser pulpotomy and formocresol pulpotomy on human primary molars.

Materials and methods

Healthy two-to eight-year-olds were treated with pulpotomies on primary molars as part of their regular dental treatment. The pulpotomy teeth were randomly assigned into one of two groups. The experimental group was treated with diode laser; the control group was treated with 1:5 dilution FC.

Results

Forty-five teeth with diode laser and 45 teeth with FC in 70 healthy children were studied. In 12 months follow-up, the clinical success rates were 92.9%, and 90.9% for laser and FC respectively, and the radiographic success rates were 78.6%, and 72.7% for laser and FC respectively. Conclusion: There is no significant difference of clinical and radiographic success rate between diode laser and FC pulpotomy in human primary molars followed for 12 months.

Photobiomodulation effect on angiogenic proteins produced and released by dental pulp cells

OBJECTIVE

To verify the photobiomodulation effect on angiogenic proteins produced and released by dental human pulpal fibroblasts (HPFs).

MATERIAL AND METHODS

HPFs were irradiated with 660-nm low-level laser at fluences of 2.5 J/cm² and 3.7 J/cm². The control group was not irradiated. MTT, crystal violet, and ELISA assays respectively verified viability, proliferation, and angiogenic protein (supernatant/lysate) at 6 h, 12 h, and 24 h after photobiomodulation. Capillary-like structure formation assay verified functional role. Two-way ANOVA/Tukey's test and ANOVA/Bonferroni's multiple comparisons test respectively verified cell viability/proliferation and intragroup and intergroup comparisons of protein synthesis (p < 0.05).

RESULTS

Irradiated and non-irradiated HPFs showed statistically similar cell viability and proliferation pattern. Intragroup comparisons showed similar patterns of protein synthesis for all groups: VEGF-A, VEGF-C, and vascular endothelial growth factor receptor 1 (VEGFR1) increased significantly in the supernatant, while FGF-2 and VEGF-A increased significantly in the lysate. The lower fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (6 h and 12 h) and VEGF-D (24 h) in the lysate, while the higher fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (12 h) in the lysate. Regardless of the time, both fluences statistically downregulated placental growth factor (PLGF) and PDGF secretion. Both fluences statistically decreased VEGF-A secretion (24 h) and PLGF production (6 h).

CONCLUSION

Photobiomodulation produced stimulatory effects on angiogenic protein secretion by pulp fibroblasts. In terms of photobiomodulation, over time, both fluences significantly increased the secretion of VEGF-A, VEGF-C, and VEGFR1 and significantly upregulated BMP-9 (6 h) in the supernatant; for capillary-like structure formation, the fluence of 2.5 J/cm² was better than the fluence of 3.7 J/cm².

CLINICAL RELEVANCE

This study results addressed effective photobiomodulation parameters tailored for pulp angiogenesis.

Effect of single and multiple doses of low-level laser therapy on viability and proliferation of stem cells from human exfoliated deciduous teeth (SHED)

The present study aimed to evaluate in vitro whether the low-level laser (LLL) delivering fractionated total energy (multiple irradiation) or single irradiation stimulates regeneration-associated events (viability and proliferation) in stem cells from human exfoliated deciduous teeth (SHED). Cells received LLL irradiation (InGaAlP-660 nm), according to the following experimental groups: G1 (single irradiation 2.5 J/cm², 10 mW, 10 s, 0.10 J), G2 (single irradiation 5.0 J/cm², 10 mW, 20 s, 0.20 J), G3 (single irradiation 7.5 J/cm², 10 mW, 30 s, 0.30 J), G4 (two irradiations 2.5 J/cm², 10 mW, 10 s; total energy 0.20 J), G5 (three irradiations 2.5 J/cm², 10 mW, 10 s; total energy 0.30 J), and G6 (non-irradiated). Cell viability was assessed by MTT and trypan blue exclusion (TBE) methods, while cell proliferation was evaluated by crystal violet (CV) and sulforhodamine B (SRB) assays after 24, 48, and 72 h after the first irradiation. By MTT, there was no difference between groups at 24 and 72 h. At 48 h, the groups subjected to multiple irradiation (G4 and G5) presented higher cell viability rates. The average percentages of viable cells for all groups by TBE method were 91.04%, 96.63%, and 97.48% at 24, 48, and 72 h, respectively. By CV, there was no significant difference between groups at 24 and 48 h; at 72 h, G2, G3, and G4 presented higher cell proliferation. By SRB, G1 and G4 presented lower proliferation rates in all the periods. When the groups presenting the same total energy were compared, G2 (0.20 J) presented lower cell viability rates and higher cell proliferation rates in comparison with G4; G3 (0.30 J) presented similar results to those of G5, with higher cell viability and proliferation. The application of laser delivering fractionated total energy (two or three applications of 2.5 J/cm²) induced higher cell viability at 48 h, while the single irradiation with 2.5 J/cm² did not stimulate metabolic activity in such period and the proliferation over time. The 5.0 and 7.5 J/cm² single doses and the three applications of 2.5 J/cm² maintained cell viability and stimulated proliferation of SHED at 72 h.

Comparison between calcium hydroxide mixtures and mineral trioxide aggregate in primary teeth pulpotomy: a randomized controlled trial

OBJECTIVES

To evaluate the effect of calcium hydroxide (CH) associated with two different vehicles as a capping material for pulp tissue in primary molars, compared with mineral trioxide aggregate (MTA).

METHODOLOGY

Forty-five primary mandibular molars with dental caries were treated by conventional pulpotomy using one of the following materials: MTA only (MTA group), CH with saline (CH+saline group) and CH with polyethylene glycol (CH+PEG group) (15 teeth/group). Clinical and periapical radiographic examinations of the pulpotomized teeth were performed 3, 6, and 12 months after treatment. Data were tested by chi-squared analysis and a multiple comparison post-test.

RESULTS

The MTA group showed both clinical and radiographic treatment success in 14/14 teeth (100%), at all follow-up appointments. By clinical evaluation, no teeth in the CH+saline and CH+PEG groups had signs of mobility, fistula, swelling or inflammation of the surrounding gingival tissue. However, in the CH+saline group, radiographic analysis detected internal resorption in up to 9/15 teeth (67%), and inter-radicular bone resorption and furcation radiolucency in up to 5/15 teeth (36%), from 3 to 12 months of follow-up. In the CH+PEG group, 2/11 teeth (18%) had internal resorption and 1/11 teeth (9%) presented bone resorption and furcation radiolucency at all follow-up appointments.

CONCLUSION

CH with PEG performed better than CH with saline as capping material for pulpotomy of primary teeth. However, both combinations yielded clinical and radiographic results inferior to those of MTA alone.

Clinical, Radiographic and Histological Evaluation of Primary Teeth Pulpotomy Using MTA And Ferric Sulfate

The aim of this study was to evaluate the clinical, radiographic and histological outcomes of the dentin-pulp complex from primary molars after pulpotomy with mineral trioxide aggregate (MTA) and 15.5% ferric sulfate (FS). Thirty-one primary molars were randomly allocated into MTA or FS groups. Clinical and radiographic evaluations were recorded at 3-, 6-, 12- and 18-month follow-up. Teeth at the regular exfoliation period were extracted and processed for histological analysis. Clinical and radiographic data were tested by statistical analysis (p≤0.01). Histological outcomes were analyzed descriptively. All of the treated teeth presented clinical success over the experimental periods. Both groups exhibited 100% of radiographic success at 3, 6 and 12 months. At the 18-month follow-up, one tooth from FS group presented inter-radicular radiolucency (p>0.01). Histologically, the treated teeth presented pulp vitality and absence of inflammatory infiltrate into the connective tissue. Only MTA group showed hard tissue barrier surrounded by odontoblasts over the pulp stumps. Both MTA and 15.5% FS are effective for pulpotomies of primary teeth. Although MTA is considered the first-choice material, FS may be a suitable alternative when treatment cost is an issue.

Clinical and Histological Study on Direct Pulp Capping With CO2 Laser Irradiation in Human Teeth

The study aimed to histologically evaluate wound healing of exposed human pulp on direct pulp capping using super-pulsed CO₂ laser preirradiation. In this single-blind clinical trial, 28 third molar teeth of 17 volunteers were randomly capped with either CO₂ laser irradiation (n=14) or Dycal (calcium hydroxide cement; n=14) and restored using resin composite. The laser was operated in super-pulsed mode (pulse duration, 0.2 ms; interval, 5.8 ms; 0.003 J/pulse). The irradiation conditions were a power output of 0.5 W, an irradiation time of 15 seconds, repeat mode (10-ms irradiation and 10-ms intervals, for a total beam exposure time of 7.5 seconds), total applied energy of 3.75 J, and an activated air-cooling system. Each tooth was extracted at six or 12 months posttreatment and prepared for histological evaluation. We evaluated the parameters of pulp tissue disorganization, inflammatory cell infiltration, reparative dentin formation (RDF), and bacterial penetration. There were no significant differences between groups for all parameters at each postoperative period (Mann-Whitney U-test, p>0.05). CO₂ laser irradiation completely controlled bleeding and exudate from the exposed pulp. The CO₂ laser group had a tendency to delay RDF compared with the Dycal group, but 4 of 7 teeth from the CO₂ laser group showed a complete dentin bridge at 12 months posttreatment.

Laser treatment contributes to maintain membrane integrity in stem cells from human exfoliated deciduous teeth (shed) under nutritional deficit

This study aimed to analyze the effects of laser irradiation on the membrane integrity and viability of stem cells from human exfoliated deciduous teeth (SHED) that were kept in serum starvation. Nutritional deficit was used to mimic the cellular stress conditions of SHED isolation for regenerative dental approaches, where laser therapy could be beneficial. SHED were cultured under serum starvation (MEMα + 1%FBS) for 1 or 24 h pre-irradiation (protocols A and B, respectively). Then, cells received low-level laser therapy (LLLT; 660 nm) at 2.5 J/cm² (0.10 W; groups I and V), 5.0 J/cm² (0.20 W; groups II and VI), 7.5 J/cm² (0.30 W; groups III and VII), or remained non-irradiated (groups IV and VIII). During irradiation, cells were maintained in 1% FBS (groups I-IV) or 10% FBS (normal culture conditions; groups V-VIII). Membrane integrity was evaluated by quantifying lactate dehydrogenase (LDH) release (immediately after irradiation), and cell viability was assessed by the MTT assay (24, 48, and 72 h post-irradiation). Serum starvation did not alter LDH release by non-irradiated SHED, while LDH release decreased significantly in groups irradiated in 1% FBS (I and III), but not in groups irradiated in 10% FBS (V-VII), regardless the pre-irradiation conditions (protocols A/B). Cell viability was significantly higher 24 h after irradiation, in most protocol A groups. In contrast, cell viability remained mostly unaltered in protocol B groups. LLLT contributed to maintain membrane integrity in SHED subjected to nutritional deficit before and during irradiation with 0.10 or 0.30 W. Short serum starvation before irradiation improved SHED viability at 24 h post-irradiation.

Clinical and Radiographic Success of Selective Caries Removal to Firm Dentin in Primary Teeth: 18-Month Follow-Up

The selective caries removal is increasingly spreading in daily clinical practice because this minimally invasive technique treats deep carious lesion and decreases the risk of pulp exposure. This case report was aimed at describing the selective removal to firm dentin on the primary mandibular left first molar of a girl aged 7 years and 6 months. The Mineral Trioxide Aggregate (MTA Angelus™) was used as liner, and the tooth was definitively restored with resin-modified glass ionomer cement (Vitremer™). The clinical and radiographic following-up was performed at 6, 12, and 18 months after treatment. The treatment showed satisfactory results after 18-month following-up, suggesting that this minimally invasive approach for carious lesion removal can replace the total removal, when properly indicated. Notwithstanding, further randomized clinical trials with longer following-up periods are still necessary.

The Effect of Low Level Laser Therapy on Direct Pulp Capping in Dogs

Introduction: The aim of this study was to determine the histologic effect of low level laser therapy (LLLT) with or without the use of mineral trioxide aggregate (MTA) on exposed pulp tissues of dogs. Methods: Twenty-five premolar teeth in three healthy mature dogs were randomly divided into five groups. In group 1, the pulp tissue was capped with MTA. In groups 2 and 3, before capping with MTA, the exposure site was irradiated by low power lasers at 630 nm (20 mW, 150 seconds, 7.5 J/cm²) and 810 nm (peak power 80 W, average power 50 mW, 1500 Hz, 50 seconds, 6.25 J/cm²) wavelengths, respectively. In groups 4 and 5, the exposure site was irradiated similar to that described in groups 2 and 3, but the pulp tissue was covered by gold foil instead of MTA. After 2 months, the animals were sacrificed and the samples were prepared for histologic evaluation. Results: There were differences in pulpal response and dentinal barrier formation among the study groups. The morphology of pulpal tissue and the integrity of dentinal barrier and formation of odontoblastic layer were more favorable in the first three groups. The occurrence of extensive and intense inflammation and necrosis was more frequent in groups 4 and 5. Conclusion: Under the conditions used in this study, the presence of MTA as a pulp capping material was more important than laser therapy in the success of direct pulp capping (DPC) treatment. MTA proved to be an effective material either alone or in combination with laser irradiation in vital pulp therapy.

Clinical Evaluation of Low Level Diode Laser Application For Primary Teeth Pulpotomy

INTRODUCTION

Inspite of latest advances in the materials and techniques practiced for the treatment of pulpally infected teeth with better reported success rate, still the question arises for safety and effectiveness of these medicaments.

AIM

The objective of the present study was to compare the effectiveness of the Low Level Laser Therapy to Mineral Trioxide Aggregate (MTA) when used for pulpotomy in vital human primary molars.

MATERIALS AND METHODS

The sample consisted of 40 primary molars from 29 children aged four to seven years. The teeth were selected based on clinical, radiographic criteria and randomly allocated to two groups. All the 40 primary molars were subjected to standard pulpotomy procedure, where in 20 molars received MTA (Group I) and 20 molars received LLLT (Group II) pulpotomy. Children were recalled at 3, 6 and 12 months intervals and pulpotomised molars were examined clinically and radiographically. Data was analysed using chi-square test.

RESULTS

MTA showed 94.7% success rate at all the three intervals, where as LLLT showed a success of 95% at three months, which decreased gradually to 85% at six months and 80% at 12 months. Intergroup comparisons were not significant.

CONCLUSION

Low level laser therapy can be considered for primary teeth pulpotomy and its success is comparable to MTA pulpotomy technique.

The use of lasers for direct pulp capping

Direct pulp capping helps extend the life of a diseased tooth by maintaining tooth vitality. Nowadays, lasers are more frequently used during direct pulp capping in the clinic, but their use has not been previously reviewed. This review presents the basic properties of currently available lasers, scientific evidence on the effects of laser application on direct pulp capping, and future directions for this technology. An extensive literature search was conducted in various databases for articles published up to January 2015. Original in vitro, in vivo, and clinical studies, reviews, and book chapters published in English were included. Various laser systems have been increasingly and successfully applied in direct pulp capping. Lasers offer excellent characteristics in terms of hemostasis and decontamination for field preparation during direct pulp capping treatment; however, the sealing of exposed pulp with one of the dental materials, such as calcium hydroxide, mineral trioxide aggregates, and bonded composite resins, is still required after laser treatment. Clinicians should consider the characteristics of each wavelength, the emission mode, irradiation exposure time, power, type of laser tip, and the distance between the laser tip and the surface being irradiated.