Systematic Review on the Role of Lasers in Endodontic Therapy: Valuable Adjunct Treatment?

Antimicrobial photodynamic therapy effects mediated by methylene blue in surfactant medium as an adjuvant treatment of teeth with apical periodontitis and presence of fistula-Protocol for randomized, controlled, double-blind clinical trial

OBJECTIVE

This study aims to evaluate the efficacy of photodynamic therapy as an adjunct to conventional endodontic treatment in patients with apical periodontitis and fistulas. In this study, a fistula is characterized as a pathological conduit originating from the infected region at the root apex of the tooth, traversing the oral mucosa, and extending to the external surface of the gingiva. This pathological condition frequently complicates the management of endodontic infections, thereby necessitating the evaluation of supplementary therapeutic interventions. The standard treatment for endodontic infections involves thorough disinfection of the root canal system to remove microbial contamination from the canal and surrounding tissues. To potentially augment the efficacy of conventional treatment, aPDT is proposed as a supplementary, non-invasive technique. This innovative technique uses a photosensitizer, which is a light-sensitive dye, in combination with a light source to produce reactive oxygen species. Reactive oxygen species can effectively target and eliminate bacteria in the root canal system, potentially enhancing treatment outcomes.

METHODS

The study will involve 140 teeth with apical periodontitis and fistulas. The teeth will be randomly assigned to one of two treatment groups. Group I will receive only the conventional endodontic treatment, which includes root canal cleaning, shaping, and obturation. Group II will undergo the same conventional endodontic treatment, but with an additional step of aPDT. The aPDT procedure involves applying a photosensitizer to the root canal and irradiating it with light to produce reactive oxygen species. Each group will consist of 70 teeth to ensure adequate statistical power. The primary outcome is fistula resolution, assessed clinically at 15 and 30 days post-treatment. The secondary outcome is the comparison of apical radiolucency from periapical radiographs to evaluate healing and reduction of periapical pathology.

CONCLUSIONS

The study aims to determine if adding aPDT significantly improves the management of apical periodontitis and overall success rates of endodontic treatment. The results will provide insights into the effectiveness of aPDT as an adjunctive treatment and its potential benefits in clinical practice.

Possibilities of Application of Cold Atmospheric Pressure Plasmas in Dentistry—A Narrative Review

According to the World Human Organization (WHO), dental and periodontal diseases are common among the human population. Traditional dentistry offers a wide range of methods for treating oral diseases and performing esthetic procedures. In contrast, cold atmospheric pressure plasma (CAPP) has been found to be a promising technology in multiple fields, particularly in medical sciences such as dentistry. In this study, CAPP might be a promising adjunct to conventional dental treatments. A substantial number of studies have confirmed the effectiveness of both direct and indirect CAPP applications in dentistry. Because CAPP technology is fast, inexpensive, and noninvasive, we aim to review recent literature focused on the application of this methodology in dentistry.

Efficacy of antimicrobial photodynamic therapy in endodontics of primary teeth: a scoping review

The objective of this study was to identify, describe and synthesize the data published about the effectiveness of antimicrobial photodynamic therapy (aPDT) in the pulpectomy of primary teeth. A search was conducted in six electronic databases and the gray literature in June and July 2023, without restrictions on language or date of publication. The search strategy included indexed terms (MeSH terms) and your synonyms. Clinical trials, in vitro studies, case reports and retrospective studies that used photodynamic therapy in primary teeth pulpectomies were considered eligible. Among the 1,674 articles retrieved, 15 were included, published between 2014 and 2022, comprising six in vitro studies, five clinical trials, and four case reports. The sample consisted of children aged 2 to 8 years of both sexes, and included 1 to 62 teeth, mostly anterior. In two in vitro studies, the sample was taken from root canals. Most studies used a diode laser, methylene blue, and optical fiber. The pre-irradiation time ranged from 1 to 5 min. All protocols demonstrated microbial reduction before and after using aPDT, with no statistical difference among the groups. Furthermore, six studies demonstrated treatment success. Despite the divergence in methodology and protocols, aPDT is an effective method for reducing microorganisms, and is a promising adjunct treatment in primary teeth pulpectomies.

Efficacy of laser adjuvant therapy in the management of post-operative endodontic pain: A systematic review and meta-analysis

BACKGROUND

Postoperative endodontic pain (PEP) is crucial in clinical practice. Recently, the effects of various laser adjuvant therapies in endodontic treatments have been widely evaluated. However, as a virtually side-effect-free treatment, its effect on postoperative pain management during endodontic treatment remains controversial.

OBJECTIVES

This review aimed to compare the efficacy of laser adjuvant therapy for pain management after endodontic treatment.

METHOD

The Cochrane Library, PubMed, Embase, Scopus and Web of Science databases were systematically searched for articles published until 12 February 2023. The risk of bias in the included studies was evaluated based on the Cochrane risk-of-bias assessment tool. Data on continuous outcomes of visual analogue scale pain scores are expressed as standard mean difference (SMD) and dichotomous outcomes of pain prevalence as relative risk (RR).

RESULTS

We included 22 studies, of which 15 enrolled 892 patients with visual analogue scale pain scores and 7 enrolled 422 patients with pain prevalence. Of the 22 studies, seven studies had a low risk of bias, 10 had a moderate risk of bias and 5 had a high risk of bias. For pain level, the pooled outcomes indicated reduced pain scores in all laser adjuvant therapy, including low-level laser therapy (SMD = -0.86 [95% CI: -1.16, -0.55] in 24 h and SMD = -0.64 [95% CI: -0.84, -0.43] in 48 h), diode laser therapy (SMD = -0.27 [95% CI: -0.50, -0.04] in 48 h) and photodynamic therapy (SMD = -1.12 [95% CI: -2.18, -0.05] in 24 h). For postoperative pain incidence, a significant correlation was observed with reduced pain incidence rates in the photodynamic therapy group (pooled RR = 0.47 [95% CI: 0.31, 0.72]) but not in the low-level laser therapy group (RR = 0.89 [95% CI: 0.30, 2.70] at 12 h and RR = 0.57 [95% CI: 0.09, 3.72] at 24 h).

CONCLUSIONS

High-quality evidence suggests that laser adjuvant therapies such as low-level laser therapy, diode laser therapy and photodynamic therapy have a positive impact on reducing postoperative endodontic pain intensity. However, the differences in PEP management effects between laser therapies are unknown, and no significant differences were observed among the subgroups.

REGISTRATION

CRD 42023402872 (PROSPERO).

Photothermal Effect of 970 nm Diode Laser Irradiation on Enterococcus faecalis Biofilms in Single-Rooted Teeth Ex Vivo

Objective: The aim of this study was to evaluate the photothermal effect of a 970 nm diode laser on Enterococcus faecalis biofilms. Methods: 72 extracted human single-rooted teeth were prepared, sterilized, and inoculated with Enterococcus faecalis to establish a two-week-old biofilm. The specimens were divided into six groups (n = 12): Group 1 (G1)-negative control (PBS-no laser), Group 2 (G2)-positive control (1% NaOCl rinse-no laser), Group 3 (G3)-a 970 nm laser in 1.5 W pulse mode, Group 4 (G4)-a 970 nm laser in 2 W pulse mode, Group 5 (G5)-a 970 nm laser in 1.5 W continuous mode, Group 6 (G6)-a 970 nm laser in 2 W continuous mode. Bacterial viability was evaluated using the LIVE/DEAD BacLight kit and analyzed by flow cytometry (FCM). Temperature changes on the root surface during irradiation were analyzed using a K-type thermocouple. Data were statistically analyzed using one-way ANOVA and Tukey's multiple comparison test (α = 0.05). Results: Bacterial viability was significantly reduced after laser irradiation in continuous mode using 1.5 W (21% of live bacteria) and 2 W (14% of live bacteria). When the pulsed mode was applied, the reduction in bacterial viability was less, with a mean survival of 53% (1.5 PF, whereas 29% of bacteria survived after 2 W irradiation). Conclusions: The 970 nm diode laser at 2 W continuous mode effectively reduced the viability of E. faecalis biofilms in root canals without causing unacceptable temperature rises at the root surface.

The influence of laser-activated irrigation on post-operative pain following root canal treatment: A systematic review

OBJECTIVES

Synthesise evidence on post-endodontic pain (PEP) in adult teeth undergoing primary root canal treatment with the adjunctive use of laser-activated irrigation (LAI) as compared with conventional needle irrigation (CNI) during the first post-operative week.

DATA

An electronic search was performed; no language constraints or restriction on the year of publication were applied.

SOURCES

Medline, Scopus, Cochrane and PubMed on 04 June 2023 STUDY SELECTION: Randomised clinical trials (RaCTs) that evaluated PEP after LAI of endodontic irrgants were included. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used. PEP was analysed at various time intervals until 1 week after treatment, related to the type of LAI used and the need for analgesia.

REULTS

Of the 793 articles identified through the electronic database search, 6 RaCTs were included. Qualitative review was favoured over meta-analysis due to substantial methodological heterogeneity between studies. Five studies were at high risk for bias determined by the Cochrane Risk-of-Bias 2 tool. Diode LAI demonstrated superior efficacy to needle irrigation in reducing pain 6-48 h post-treatment. The impact of LAI by photon-induced photoacoustic streaming (PIPS) was unclear and no difference was observed between PIPS and needle irrigation. However, PIPS mitigated PEP better than manual dynamic activation, sonic and ultrasonic activation. There was no difference in analgesia intake between LAI and needle irrigation groups.

CONCLUSIONS

LAI may help reduce PEP in the first 48 h. Methodological standardisation of future RaCTs on LAI would be beneficial in allowing a more accurate review with the possibility of quantitative synthesis.

CLINICAL SIGNIFICANCE

This unique synthesis used stringent criteria to reduce confounding factors and provided valuable evidence regarding PEP with different types of LAI. It helps clinicians choose an appropriate LAI technique as compared with CNI and predicts a time frame for reducing PEP.

Influence of extracellular matrix scaffolds on histological outcomes of regenerative endodontics in experimental animal models: a systematic review

BACKGROUND

Decellularized extracellular matrix (dECM) from several tissue sources has been proposed as a promising alternative to conventional scaffolds used in regenerative endodontic procedures (REPs). This systematic review aimed to evaluate the histological outcomes of studies utilizing dECM-derived scaffolds for REPs and to analyse the contributing factors that might influence the nature of regenerated tissues.

METHODS

The PRISMA 2020 guidelines were used. A search of articles published until April 2024 was conducted in Google Scholar, Scopus, PubMed and Web of Science databases. Additional records were manually searched in major endodontic journals. Original articles including histological results of dECM in REPs and in-vivo studies were included while reviews, in-vitro studies and clinical trials were excluded. The quality assessment of the included studies was analysed using the ARRIVE guidelines. Risk of Bias assessment was done using the (SYRCLE) risk of bias tool.

RESULTS

Out of the 387 studies obtained, 17 studies were included for analysis. In most studies, when used as scaffolds with or without exogenous cells, dECM showed the potential to enhance angiogenesis, dentinogenesis and to regenerate pulp-like and dentin-like tissues. However, the included studies showed heterogeneity of decellularization methods, animal models, scaffold source, form and delivery, as well as high risk of bias and average quality of evidence.

DISCUSSION

Decellularized ECM-derived scaffolds could offer a potential off-the-shelf scaffold for dentin-pulp regeneration in REPs. However, due to the methodological heterogeneity and the average quality of the studies included in this review, the overall effectiveness of decellularized ECM-derived scaffolds is still unclear. More standardized preclinical research is needed as well as well-constructed clinical trials to prove the efficacy of these scaffolds for clinical translation.

OTHER

The protocol was registered in PROSPERO database #CRD42023433026. This review was funded by the Science, Technology and Innovation Funding Authority (STDF) under grant number (44426).

The Effect of Lasers on the Healing of Periapical Lesion: A Systematic Review

Introduction: Endodontic treatment of teeth with periapical lesions presents more clinical difficulty. Various lasers in several methods are used in endodontics, and most of them are utilized as an adjunctive protocol in order to reduce the bacterial load of the root canal system. Improved disinfection plays a crucial role in enhanced and accelerated healing of periapical lesions. This review aims to summarize studies assessing the effect of lasers on periapical lesion healing. Methods: PubMed/MEDLINE, Scopus, Embase, and Web of Science (ISI) online databases were searched, with no publication year or status restriction, for relevant articles on April 2023. Clinical studies evaluating the effect of laser application on the periapical lesion of patients using radiographic assessment were considered eligible for inclusion. Results: Eight studies were included after carefully screening the obtained articles, first by their title and abstract and then by their full texts. Diode (4), Er, Cr: YSGG (3), and Nd: YAG (1) lasers were used with output powers that varied from 0.75 to 2 watts. Photodynamic therapy was employed in two studies, and in other studies, the root canal system was directly irradiated. Irradiation of the root canal system was adjunctive to standard preparation in all studies. The healing of the teeth treated with lasers was not inferior to those conventionally treated. In all of the included studies, laser application outperformed the standard cleaning and shaping protocol; however, this improved or faster healing was not statistically significant in most studies. Conclusion: Lasers might expedite and improve the healing process of periapical lesions. Since lasers enhance the quality of cleaning of the root canal system, it is hard to point out the exact mechanism of it. Further investigations are needed to realize the effectiveness of this treatment modality and to discover the underlying biological concepts.

Effect of Laser Therapy on Postoperative Pain and Endodontic Retreatment: A Systematic Review and Meta-Analysis

BACKGROUND

Root canal re-treatment (RCR) cases are considered some of the most challenging cases in the field of endodontics, as they are mostly associated with various iatrogenic errors such as ledge formation, incomplete biomechanical preparation, file separation, and incomplete obturation. These iatrogenic errors lead to defective niches within root canals that may act as reservoirs for various viable microorganisms. Such residual microbial niches may cause postoperative pain even after thorough debridement and reshaping the canals, ultimately leading to a poor prognosis for the tooth. Nowadays, prevention of postoperative pain in re-treatment cases and prognosis are effectively managed by photobiomodulation therapy (PBMT).

METHOD

Relevant studies in the English language published before November 2022 were identified using electronic databases like PubMed, SCOPUS, and EBSCO to conduct bibliographic research. This systematic review is based on 3 studies that were found eligible as per the inclusion and exclusion criteria. This systematic review is in accordance with PRISMA guidelines.

RESULTS

The systematic review indicated a positive impact by significantly decreasing postoperative pain in RCR cases when treated with PBMT. The variation was statistically significant at 24 hours (P = .0002), 48 hours (P = .03), and 72 hours (P = .02). The mean difference at 24 hours was 0.65 (95% CI, 0.32-0.99), at 48 hours was 0.46 (95% CI, 0.05-0.87), and at 72 hours was 0.40 (95% CI, 0.07-0.74). There was no statistical heterogenicity at 24 hours (P > .05), but a medium heterogenicity was observed at 48 hours and 72 hours.

PRACTICAL IMPLICATION

PBMT or low-level laser therapy has shown superior results as compared to the conventional pharmacologic approach in postoperative pain management in RCR cases.

Review of Approaches to the Management of Vertical Dental Root Fractures and Tooth Preservation

A vertical root fracture (VRF) is a complex condition in which the fracture lines can be partial or complete and extend along the long axis of the tooth. Considering the nature of the damage and the low likelihood of a successful outcome, such fractures can be difficult to manage. Their management typically involves complex endodontic or surgical procedures, which can be technically challenging for general dentists. Recent advancements introduce promising techniques, such as intentional replantation, adhesive methodologies, and regenerative procedures, showcasing potential in salvaging teeth affected by VRFs. Nonetheless, the imprecise nature of symptoms necessitates meticulous case evaluation by clinicians. Comprehensive patient counseling regarding diverse treatment options and potential ramifications remains crucial to preserving the affected tooth. Preserving a vertically fractured tooth aids in improving both function and aesthetics while safeguarding the arch's integrity by maintaining the height of the alveolar bone. It is important to note that the success of the treatment procedures depends on the extent and location of the fracture, the condition of the tooth and fragment, and the skill of the dental professional performing the treatment. This review highlights the complexity of VRF management, emphasizing the necessity for precise evaluation, patient education, and the exploration of innovative techniques. It aims to review the treatment of VRFs, ranging from classical to contemporary methods, with a focus on tooth preservation. The establishment of standardized protocols and conduct of further research to ascertain long-term efficacy are imperative in optimizing outcomes and retaining natural dentition in cases of VRFs.

Effect of photobiomodulation on postoperative endodontic pain: A systematic review of clinical trials

Background

This review aims to perform a complete evaluation of the impact of photobiomodulation (PMB) on postoperative endodontic pain.

Materials and Methods

The PRISMA checklist was used to perform this systematic review. The electronic databases were searched, including Google Scholar, PubMed, and Embase. Sixty-three papers were obtained through a main electronic search and a hand search. Nine trials met the criteria after screening the titles, abstracts, and/or full texts.

Results

Seven out of nine studies showed that PMB has a significant impact on relieving postoperative endodontic pain, with no statistically significant difference in the severity of pain between the laser and control groups in the two remaining studies. In addition, eight studies showed no adverse effects, indicating that we can remove the adverse effects of drugs such as nonsteroidal anti-inflammatory drugs. However, one study showed evidence of the consequences of PMB application on teeth with symptomatic irreversible pulpitis. Therefore, it can be concluded that PMB should not be used in teeth with pain because of irreversible pulpitis.

Conclusion

Although there is some understanding from a cellular viewpoint of the effects of PMB, there is still some uncertainty about whether these cell-level modifications impact reducing the postendodontic pain.

Comprehensive Strategies in Endodontic Pain Management: An Integrative Narrative Review

This narrative review comprehensively examines the current and emerging strategies for pain management in endodontics, encompassing a wide range of pharmacological and non-pharmacological approaches. Through an extensive exploration of 20 distinct parts, the review discusses traditional analgesics, antibiotics, the use of corticosteroids, and the role of novel treatments such as platelet-rich fibrin (PRF) and cryotherapy. The review also delves into the intricacies of clinical methods, such as trephination and occlusal reduction, and discusses the potential of advanced techniques such as GABAergic signaling, acupuncture, in silico modulation, and low-level laser therapy (LLLT) for the effective management of endodontic pain. The analysis reveals a trend toward integrative methods that combine established practices with cutting-edge research, highlighting the importance of a tailored approach in endodontic pain management. The findings underscore the significance of understanding the complex nature of dental pain and the need for multifaceted treatment strategies. The review emphasizes that while traditional pharmacological methods remain foundational, emerging therapies offer promising adjuncts or alternatives, especially in cases where conventional treatments may be inadequate or unsuitable. This review aims to serve as a comprehensive resource for endodontic practitioners and researchers, offering insights into the multifarious aspects of pain management in endodontics. It underscores the ongoing evolution in the field and suggests directions for future research, particularly in refining and validating new pain management techniques.

Comparison of postoperative pain reduction following laser, ultrasonic activation and conventional needle irrigation after root canal treatment - A randomized clinical trial

Background

To compare the incidence of postoperative pain and analgesic intake on the administration of passive ultrasonic irrigation (PUI) using IrriSafeTM, laser-activated irrigation (LAI) using Er:Cr: YSGG in comparison to conventional needle irrigation (CNI) in participants diagnosed with symptomatic irreversible pulpitis (SIP).

Material and Methods

In this randomised double-blinded parallel trial, 75 participants requiring root canal treatment in mandibular first molars diagnosed with SIP were enrolled. A 10 cm visual analogue scale (VAS) was used for pain assessment and patients presented with a preoperative pain score of 5 cm and above were only selected. After biomechanical preparation, the final irrigation protocols varied based on the irrigation protocol employed. In CNI, intracanal irrigation was conducted without agitation using a 31G side vented needle. In PUI, irrigant activation was conducted using IrriSafeTM and in LAI, irrigant activation was conducted using a pulsed Er:Cr: YSGG (2940 nm) laser with radial firing tip (RFT - 2). The pain scores and analgesic intake were assessed postoperatively after obturation at 6, 24 and 48 h.

Results

A significant reduction in postoperative pain levels and analgesic intake was seen among all groups at assessed time intervals (p<0.05). Overall, mean postoperative pain scores and analgesic intake were CNI>LAI>PUI (p<0.05) respectively.

Conclusions

Participants diagnosed with SIP receiving PUI and LAI showed low and comparable levels of postoperative pain scores. Based on the analgesic intake, PUI showed the least analgesic intake when compared to LAI and CNI respectively. Key words:Endodontics, Root canal irrigants, Postoperative Pain, Passive ultrasonic activation, Laser ultrasonic activation.

Evaluation the antibacterial efficacy of sodium hypochlorite in combination with two different photodynamic therapy protocols against Enterococcus Faecalis in Infected root canals: An in-vitro experiment

BACKGROUND

Photodynamic therapy (PDT) is an antimicrobial approach that can be used as an adjunctive safe technique for root canal disinfection. In this study, we aimed to evaluate the antibacterial efficacy of PDT with indocyanine green and toluidine blue in combination with sodium hypochlorite (NaOCl) in compared with NaOCl alone against Enterococcus faecalis in infected root canals.

METHODS

Sixty five root canals of sound human premolars were collected. First, the teeth were sterilized, then 60 root canals were inoculated with the E. faecalis, and 5 samples served as negative control remained uncontaminated. The contaminated root canals were randomly assigned into 4 experimental groups (n=15): (1) NaOCl, (2) NaOCl+ PDT-1 (toluidine blue + 630nm LED), (3) NaOCl+ PDT-2 (indocyanine green + 808nm diode laser), and (4): positive control (no treatment). Then, the colony-forming units (CFU/mL) of E. faecalis were calculated in all the groups. Moreover, 5 samples from each group were examined under a scanning electron microscope. The data were analyzed by independent T-test and the Mann-Whitney U test at the significance level of 0.05.

RESULTS

The CFU count was significantly lower in the indocyanine green-PDT group in comparison with other groups (p˂0.05). The mean of CFU in the positive control group was significantly higher than the other groups (p˂0.05). No significant difference was detected between NaOCl and toluidine blue -PDT group (p=1.00).

CONCLUSION

Indocyanine green- PDT improved the antibacterial effects of NaOCl against E. faecalis, while toluidine blue - mediated PDT had no significant additional effect on NaOCl.

Irrigation - does it affect post-operative pain?

DESIGN

A randomised control trial involving eighty patients who were blindly allocated into four different groups for different disinfection and irrigation methods on lower permanent molars. The patients were treated by one experienced endodontist across two visits. The four methods of irrigation used were: 1. Conventional irrigation 2. Sonic irrigation activation system 3. Irradiation with a 980 nm diode laser and conventional irrigation 4. Irradiation with a 980 nm diode laser and sonic irrigation activation system Pain levels were then assessed postoperatively at 8 h, 24 h, 48 h and 7 days following access and chemomechanical preparation at the first visit.

CASE SELECTION

Eighty patients who visited the Endodontic Department at Biruni University were included in the study. Those who were included were healthy adults, experiencing moderate to severe pain (self-scored from 4 to 10, based on a 0 to 10 pain scale) at the start of treatment and those who were given a dental diagnosis of 'symptomatic apical periodontitis' with a negative cold test in a mandibular molar.

DATA ANALYSIS

Qualitative data was analysed using a chi-square test, Fisher's exact chi-square test and Fisher-Freeman-Halton exact test. The Kruskal-Wallis test and Willcoxon test were used to assess inter-group and intra-group parameters.

RESULTS

The study found that patients in all groups experienced a statistically significant decrease in pain levels postoperatively. However, different irrigation methods resulted in no statistically significant differences in pain levels. There were also no statistically significant differences based on gender or age. Statistical significance was reached when p < 0.05.

CONCLUSIONS

The use of sonic irrigation activation and irradiation with a 980 nm diode laser did not significantly reduce post-operative pain in adult mandibular molars undergoing endodontic treatment when compared to conventional irrigation methods.

Analysis of Temperatures Generated during Conventional Laser Irradiation of Root Canals-A Finite Element Study

The success of endodontic treatment is dependent on the removal of bacteria. A modern strategy to reduce bacterial load is laser irradiation. During this procedure, there is a local increase in temperature with possible side effects. The aim of this study was to determine the thermal behavior of a maxillary first molar when performing the conventional irradiation technique using a diode laser. For this study, a 3D virtual model of a maxillary first molar was created. The preparation of the access cavity, the rotary instrumentation of the palatal root canal and the laser irradiation protocol were simulated. The model was exported in a finite element analysis program where the temperature and heat flux were studied. Temperature and heat flux maps were obtained, and the temperature increase on the internal wall of the root canal was analyzed. The maximum temperature value exceeded 400 °C and was maintained for less than 0.5 s. The obtained temperature maps support the bactericidal effect of diode laser and the limitation of damage to surrounding tissues. On internal root walls, the temperature reached several hundred degrees Celsius, but for very short durations. Conventional laser irradiation is an adjuvant method of decontamination of the endodontic system.

Regenerative endodontic therapy in mature teeth with necrotic pulp and apical periodontitis using two disinfection protocols

OBJECTIVE

This study compared the effect of diode laser (DL) 980 nm and double antibiotic paste (DAP) on response of mature teeth with necrotic pulp and apical periodontitis to regenerative endodontic therapy in a dog model.

METHODS

Pulp necrosis and periapical pathosis were induced in 40 mature double rooted premolars in four 2-year-old mongrel dogs. These teeth were randomly divided according to disinfection protocol into four equal groups (10 teeth each/20 roots), group I: DAP; group II: DL980 nm; group III: positive control (without treatment) and group IV: negative control (untouched teeth). These groups were further subdivided into 2 subgroups (5 teeth each/10 roots) according to evaluation period, subgroup (A): one month and subgroup (B): three months. Revascularization techniques were performed using bleeding induction and application of platelet rich fibrin (PRF). The coronal cavities were sealed with mineral trioxide aggregate (MTA) and glass ionomer cement. The inflammatory response, vital tissue in-growth, new hard tissue formation and bone resorption were assessed. Statistical analysis was done utilizing ANOVA, Tukey's post hoc and paired t tests.

RESULTS

In both subgroups, there were no significant differences between DAP and DL980 in terms of inflammatory cell count, vital tissue in-growth, new hard tissue formation and bone resorption (P ≤ 0.05).

CONCLUSION

Diode laser 980 nm can alternate DAP as a disinfection method of the root canal during RET for mature necrotic teeth, therefore it may accelerate regenerative endodontic therapy for both the patient and dentist and allows for RET in a single appointment.

Current Applications and Future Directions of Lasers in Endodontics: A Narrative Review

The utilization of lasers has been regarded as a novel technique for the purposes of clinical use in the dental field. Recently, numerous studies have been conducted on the potential applications of laser therapy in endodontics. Moreover, due to their ablation, penetrability, and disinfection capabilities, lasers have performed well with respect to endodontic treatments, including root canal treatment, vital pulp therapy (pulp capping and pulpotomy), dentinal hypersensitivity treatment, and management of dental pain related to pulp and periradicular disease. In particular, the superiorities of laser-aided pulp therapy are emphasized through condensed clinical controlled trials, and histological studies, in this review. Moreover, the ingenious use of laser applications with respect to aiding in the acceleration of root development and the extraction of foreign matters (i.e., broken files and fiber posts) in canals has quickly become the cutting-edge trend of current research. This review offers a summary and discussion of the current literature on all the aforementioned laser applications. Moreover, the characteristics of laser devices, including erbium lasers, neodymium-doped lasers, CO2 lasers, and diode lasers, are detailed and discussed here, providing useful references for laser application in endodontics. We also focus on the different wavelengths with respect to the lasers that are applied in endodontics. High-power lasers perform well as operative instruments; in addition, low-level lasers lead to the regulation of pulp inflammation, and the promotion of pulp healing. This narrative review provides a summary of the advanced applications of lasers in conjunction with various devices in the practice of endodontics, and aims to inspire innovative perspectives on lasers in the context of the treatment of dental diseases, especially pulp diseases, in the future.

Global research trends on photodynamic therapy in endodontics: A bibliometric analysis

BACKGROUND

Photodynamic therapy (PDT) is an adjunctive treatment that aims to inactivate microorganisms through an oxidative reaction produced by irradiating a photosensitizing agent. The quest for improved root canal disinfection has sought supplementary methods when performing chemomechanical procedures. From this perspective, PDT protocols were proposed as an auxiliary approach in endodontics. Thus, the aim of this study was to investigate publication metrics and research trends related to this scope.

METHODS

This review is reported in accordance with the PRISMA 2020 recommendations. Two blinded and independent reviewers systematically searched five electronic databases until December 2021. The acquired bibliometric parameters were analyzed through descriptive statistics and graphical mappings with VOSViewer software.

RESULTS

The search retrieved 342 studies from 84 journals originating from 33 countries. About 85% of the included studies were published over the last decade. Most of the available evidence is laboratory-based (74.5%), and the main clinical outcomes evaluated were microbiological load reduction and postoperative pain. Mayram Pourhajibagher is the researcher with the most publications as the first author (n = 16). Tehran University of Medical Sciences carried out the highest number of studies (n = 29), and Photodiagnosis and Photodynamic Therapy is the journal that most published on the theme (n = 111).

CONCLUSIONS

This bibliometric analysis mapped and discussed the scientific progress and publication metrics in PDT in endodontic research. Additionally, future perspectives were highlighted and should focus on discovering new photosensitizer agents, standardizing optimal photoactivation protocols, and conducting more clinical-oriented research.

Essential oils as adjuvants in endodontic therapy: myth or reality?

To enhance endodontics, the search for new antibacterials that can improve infected tooth root canal treatment is ongoing. As potent antibacterial and antibiofilm agents, essential oils (EOs) have been suggested as novel endodontic materials. Several studies indicate that EO-based irrigants and medicaments show promising reductive potential against the most important intracanal pathogen, Enterococcus faecalis, and notably contribute to intracanal biofilm eradication. In terms of additional benefits that EO-based endodontic materials can provide, their antioxidant and anti-inflammatory potential are also important, but they have only scarcely been explored in research. Investigations into the benefits of EO-based endodontic materials together with their biocompatibility are needed. The results presented in this review strongly encourage further research on this topic.

Outcomes reporting in systematic reviews on non-surgical root canal treatment: A scoping review for the development of a core outcome set

BACKGROUND

Studies related to non-surgical root canal treatment are amongst the most frequently performed clinical studies in endodontics. However, heterogeneity in reporting outcomes and lack of standardization is a significant challenge to evidence synthesis and guideline development.

OBJECTIVES

The aims of the present scoping review were to (a) identify outcomes reported in systematic reviews evaluating non-surgical root canal treatment; (b) identify how and when the reported outcomes were measured; (c) assess possible selective reporting bias in the included studies. The information obtained in this study should inform the development of a core outcome set (COS) for non-surgical root canal treatment.

METHODOLOGY

Structured literature searches were performed to identify systematic reviews on non-surgical root canal treatments published in English between January 1990 and December 2020. Two reviewers undertook study selection and data extraction. Outcomes were categorized according to a healthcare taxonomy into five core areas (survival, clinical/physiological changes, life impact, resource use, and adverse events). The outcome measurement tools and length of follow-up were recorded.

RESULTS

Seventy-five systematic reviews were included, of which 40 included meta-analyses. Most reviews reported on physiological and clinical outcomes, primarily pain and/or radiographic assessment of periapical status, and a variety of measurement tools and scales were used. Few reviews focused on tooth survival, life impact, resources, and adverse events. The heterogeneity amongst the reviews was large on all parameters. Less than 40% of the reviews assessed the risk of selective reporting.

DISCUSSION

Overall aims of the included reviews were highly heterogenic; thus, outcomes and how they were measured also varied considerably. Patient-centred outcomes and the use of resources were rarely reported on.

CONCLUSIONS

Most studies reported on physiological and clinical outcomes, in particular pain and/or radiographic healing. Measurement tools, scales, thresholds, and follow-up periods varied greatly within each outcome, making comparison across studies complicated. Less than 40% of the reviews assessed risk of selective reporting; thus, selective bias could not be ruled out. The presented information on reported outcomes, measurement tools and scales, and length of follow-up may guide the planning of future research and inform the development of a COS for non-surgical root canal treatment.

Microrobotics for Precision Biofilm Diagnostics and Treatment

Advances in small-scale robotics and nanotechnology are providing previously unimagined opportunities for new diagnostic and therapeutic approaches with high precision, control, and efficiency. We designed microrobots for tetherless biofilm treatment and retrieval using iron oxide nanoparticles (NPs) with dual catalytic-magnetic functionality as building blocks. We show 2 distinct microrobotic platforms. The first system is formed from NPs that assemble into aggregated microswarms under magnetic fields that can be controlled to disrupt and retrieve biofilm samples for microbial analysis. The second platform is composed of 3-dimensional (3D) micromolded opacifier-infused soft helicoids with embedded catalytic-magnetic NPs that can be visualized via existing radiographic imaging techniques and controlled magnetically inside the root canal, uninterrupted by the soft and hard tissues surrounding the teeth in an ex vivo model. These microrobots placed inside the root canal can remove biofilms and be efficiently guided with microscale precision. The proof-of-concept paradigm described here can be adapted to target difficult-to-reach anatomical spaces in other natural and implanted surfaces in an automated and tether-free manner.

Influence of Laser Irradiation Settings, during Diode-Assisted Endodontics, on the Intraradicular Adhesion of Self-Etch and Self-Curing Luting Cement during Restoration-An Ex Vivo Study

Background: Diode-assisted endodontics is nowadays utilized for pulp space disinfection, but little is known on the bonding potential of this lased root dentin when the tooth is restored with an intracanal polymer post. Objectives: to investigate the influence of diode laser irradiation settings, in laser-assisted endodontics, on the intraradicular bonding of composite materials. Methods: Sixteen two-rooted, maxillary first premolars were collected, prepared up to F4 (Protaper Universal. Dentsply-Maillefer, Ballaigues, Switzerland), and randomly assigned in two groups: group A (chopped mode or short pulse), diode irradiated according to protocol, pulse 25 ms, power 2.5 W, and group B (microchopped mode or ultrashort pulse), pulse 25 μs, peak power 12 W (both groups GentleRay. KaVo Dental, Biberach an der Riss, Germany). Buccal canals were irradiated, palatal ones served as controls. Canals were then obturated, post space was created in all canals, and quartz-fiber posts (ICE light Danville. Danville Materials, San Ramon, CA, USA) were cemented by self-etch self-curing cement (Max Cem Elite. Kerr, West Collins Orange, CA, USA) (Max Cem Elite. Kerr, Brea, CA, USA). A week later, teeth were sectioned horizontally in 1 mm increments. Push-out test was conducted in a Zwick testing machine (Zwick Roell, Ulm, Germany) at 1 mm/min speed, and the force required to dislodge the post from each specimen (F-max) was recorded. Weibull regression models were applied for statistical analyses. Results: Differences in F-max by group (control vs. chopped mode vs. microchopped mode) and height (meaning the apical-to-coronal position of each specimen along the root) were statistically significant (p < 0.05 in all cases). Conclusions: Short pulses (or chopped mode) had a profound positive effect on the quality of intraradicular bonding, while Ultrashort pulses (or microchopped mode) affected it negatively. In addition, apically positioned bonding proved weaker compared with more coronally located specimens.

Protocol for the clinical practice of photodynamic therapy in endodontics: assessment of guideline quality using the AGREE II instrument

BACKGROUND

The choice of parameters in Photodynamic Therapy for endodontic treatment, such as wavelength, energy, application time, and number of sessions can vary based on the characteristics of the procedure and the patient. Providing information supported by scientific evidence in an accessible way to clinicians who are unfamiliar with the literature is necessary. Thus, this study aimed to synthesize a clinical protocol for the use of photodynamic therapy in endodontics in permanent teeth.

METHODS

Protocols with high methodological quality were identified using a literature search and the Appraisal of Guidelines Research and Evaluation Instrument (AGREE II), a validated tool for assessing quality. The recommendations of these studies were synthesized and submitted to a group of experts for evaluation and adaptation, and consensus was assessed using the Delphi methodology.

RESULTS

The analysis of the literature on the application of antimicrobial photodynamic therapy in endodontics showed that clinical trials with good levels of evidence and clinical recommendations have been reported previously, with two studies identified as having a clinical recommendation level of A1A and an evidence level of A.

CONCLUSION

The written protocol was considered to be satisfactory and as having appropriate content validity during the second round of evaluation by the experts. The studies included in this research were predominantly explanatory in nature, highlighting the need for pragmatic designs to increase the degree of clinical applicability.

Effect of Chemical Debridement and Irrigant Activation on Endodontic Treatment Outcomes: An Updated Overview

Chemical debridement is considered one of the most important steps during root canal treatment to target unreached areas and provide thorough disinfection of the canals. The efficiency of this step efficiency can be increased using different agitation and irrigation techniques/devices. This comprehensive review aimed to summarize the effect of various irrigant activation and agitation techniques/devices on endodontic treatment outcomes. Using mechanical active irrigation, which enables the activation or agitation of the irrigating solution, is beneficial in root canal treatment by increasing the efficiency of delivering the irrigant up to working length and ensuring isthmus cleanliness. However, considerable variation was noticed between the protocols used in each technique with a lack of well-designed randomized clinical trials to focus on the long-term outcome. Moreover, a low level of evidence was noticed regarding the effectiveness of certain activation techniques over others. Therefore, each study needs to be carefully weighed before using its results and embracing its conclusion. Future studies need to focus more on the antimicrobial effect of each technique and its effect on the healing of apical periodontitis. Also, recent advances, such as multisonic and laser activation, are promising tools that need more clinical investigations to show their efficiency.

The influence of delivery power losses and full operating parametry on the effectiveness of diode visible-near infra-red (445-1064 nm) laser therapy in dentistry-a multi-centre investigation

The development of protocols for laser-assisted therapy demands strict compliance with comprehensive operating parametry. The purpose of this investigation was to examine the accuracy of correlation between laser control panel and fibre emission power values in a selection of diode dental lasers. Through retrospective analysis using successive systematic review and meta-analysis, it is clear that there is inconsistency in the details, and possible inaccuracies in laser power applied and associated computed data. Through a multi-centre investigation, 38 semi-conductor ("diode") dental laser units were chosen, with emission wavelengths ranging from 445 to 1064 nm. Each unit had been recently serviced according to manufacturer's recommendations, and delivery fibre assembly checked for patency and correct alignment with the parent laser unit. Subject to the output capacity of each laser, four average power values were chosen using the laser control panel-100 mW, 500 mW, 1.0 W, and 2.0 W. Using a calibrated power meter, the post-fibre emission power value was measured, and a percentage power loss calculated. For each emission, a series of six measurements were made and analysed to investigate sources of power losses along the delivery fibre, and to evaluate the precision of power loss determinations. Statistical analysis of a dataset comprising % deviations from power setting levels was performed using a factorial ANOVA model, and this demonstrated very highly significant differences between devices tested and emission power levels applied (p < 10-142 and < 10-52 respectively). The devices × emission power interaction effect was also markedly significant (p < 10-66), and this confirmed that differences observed in these deviations for each prior power setting parameter were dependent on the device employed for delivery. Power losses were found to be negatively related to power settings applied. Significant differences have emerged to recommend the need to standardize a minimum set of parameters that should form the basis of comparative research into laser-tissue interactions, both in vitro and in vivo.