Enhancing Wetland Mapping: Integrating Sentinel-1/2, GEDI Data, and Google Earth Engine.

Wetlands are amongst Earth's most dynamic and complex ecological resources, serving productive and biodiverse ecosystems. Enhancing the quality of wetland mapping through Earth observation (EO) data is essential for improving effective management and conservation practices. However, the achievement of reliable and accurate wetland mapping faces challenges due to the heterogeneous and fragmented landscape of wetlands, along with spectral similarities among different wetland classes. The present study aims to produce advanced 10 m spatial resolution wetland classification maps for four pilot sites on the Island of Newfoundland in Canada. Employing a comprehensive and multidisciplinary approach, this research leverages the synergistic use of optical, synthetic aperture radar (SAR), and light detection and ranging (LiDAR) data. It focuses on ecological and hydrological interpretation using multi-source and multi-sensor EO data to evaluate their effectiveness in identifying wetland classes. The diverse data sources include Sentinel-1 and -2 satellite imagery, Global Ecosystem Dynamics Investigation (GEDI) LiDAR footprints, the Multi-Error-Removed Improved-Terrain (MERIT) Hydro dataset, and the European ReAnalysis (ERA5) dataset. Elevation data and topographical derivatives, such as slope and aspect, were also included in the analysis. The study evaluates the added value of incorporating these new data sources into wetland mapping. Using the Google Earth Engine (GEE) platform and the Random Forest (RF) model, two main objectives are pursued: (1) integrating the GEDI LiDAR footprint heights with multi-source datasets to generate a 10 m vegetation canopy height (VCH) map and (2) seeking to enhance wetland mapping by utilizing the VCH map as an input predictor. Results highlight the significant role of the VCH variable derived from GEDI samples in enhancing wetland classification accuracy, as it provides a vertical profile of vegetation. Accordingly, VCH reached the highest accuracy with a coefficient of determination (R2) of 0.69, a root-mean-square error (RMSE) of 1.51 m, and a mean absolute error (MAE) of 1.26 m. Leveraging VCH in the classification procedure improved the accuracy, with a maximum overall accuracy of 93.45%, a kappa coefficient of 0.92, and an F1 score of 0.88. This study underscores the importance of multi-source and multi-sensor approaches incorporating diverse EO data to address various factors for effective wetland mapping. The results are expected to benefit future wetland mapping studies.

Long-Term Outcome of Horizontal Root Fractures in Permanent Teeth: A Retrospective Cohort Study.

INTRODUCTION: Horizontal root fracture (HRF) is a complex traumatic dental injury that affects the pulp, dentin, cementum, and periodontal ligament. This retrospective cohort study evaluated treatment outcomes in permanent teeth with HRF. METHODS: We analyzed clinical and radiographic data from a dental trauma center (2006-2022). Permanent teeth with HRF with a follow up of ≥12 weeks were considered for outcome assessment (defined as clinical normalcy and radiographic healing at the fracture line). Prognostic factors were identified through multivariable logistic regression analyses (P value ≤ .05). RESULTS: 125 teeth from 103 patients were included. After a median follow-up of 79 weeks, the overall favorable outcome was 92%. This includes teeth that received emergency splinting/repositioning at baseline (62.2%) and those that received subsequent endodontic intervention for the coronal fragment (baseline: 85%; subsequent follow-ups: 91.8%). Being male and incomplete root development were both significantly associated with a better outcome of splinting/repositioning (OR = 2.58; 95% CI, 1.06-6.24 and OR = 4.37; 95% CI, 1.16-16.41, respectively) and a reduced likelihood of requiring endodontic treatment (OR = 0.44; 95% CI, 0.20-0.96 and OR = 0.24; 95% CI, 0.08-0.76, respectively). Treatment delays surpassing one week were significantly associated with an increased likelihood of requiring endodontic treatment compared to timely presentations within 24 hours (OR = 3.06; 95% CI, 1.07-8.77; P value < .05). CONCLUSION: With timely diagnosis and treatment, and close monitoring, HRF cases can achieve a 92% favorable outcome. Male sex and incomplete root development correlate with improved baseline outcomes and a reduced need for endodontic treatment. Conversely, delayed presentation increases the likelihood of requiring endodontic intervention.

Endodontic treatment of a C-shaped mandibular second molar with narrow dentinal thickness: A case report.

Formulating an effective root canal treatment plan necessitates clinician awareness of the complexities of the root canal system and possible anatomic challenges. The C-shaped canal variation accompanying the radicular lingual groove makes the lingual dentinal wall so thin that cleaning and shaping of canals require accurate management. This report presents endodontic treatment of a C-shaped mandibular second molar diagnosed with pulpal necrosis and asymptomatic apical periodontitis, that initial radiographic assessment revealed extremely thin (0.3 mm) width of the lingual wall of the canals prone to perforation. Mechanical preparation was performed through the anti-curvature technique and basically by chemical irrigation rather than mechanical instrumentation. The C-shaped isthmus was prepared up to 25/02 rotary system without dentinal defect while maintaining adequate dentin thickness so as to not significantly reduce the strength of the root. Follow-up radiographs showed normal periodontal ligament and lamina dura indicating significant healing of the periapical lesion.

Tooth Discoloration and Solubility of Zinc Oxide Eugenol Combined with Different Concentrations of Nano-Curcumin: An in vitro Study.

Statement of the Problem: Due to the unfavorable properties of eugenol, the eugenol content can be reduced to improve the properties of zinc oxide eugenol (ZOE) by making a new combination of nanocurcumin called curcumin pulpal paste (CPP). Purpose: The aim of this in vitro study was to evaluate the solubility and tooth discoloration of three concentrations of CPP compared to ZOE, and Metapex. Materials and Method: In this in vitro study for evaluating of the solubility, five groups including ZOE, Metapex, and three concentrations of CPP (5%, 10%, and 20%) were tested. For evaluating the solubility, the changes in of the weight of samples were measured at 1, 3, 7 and 30 days after initial setting. In order to evaluate the tooth discoloration, 75 bovine maxillary anterior teeth were filled with one of five pulpal pastes. The changes in tooth color were evaluated at 1 hour, 1 week, 1 and 3 months after material placement. Results: The solubility increased by increasing the nano-curcumin percentage in CPPs. After 30 days, the solubility of the 5%CPP, and ZOE was not significantly different (p= 1.000). According to the colorimetric test, after 3 months, the highest discoloration was recorded for 20% CPP (8.45), and the smallest discoloration was registered for Metapex (4.06). The discoloration of 5% CPP, and 10% CPP was similar to ZOE's color change (p> 0.05). Conclusion: The results of the present study showed that the solubility of pulpal paste has increased with increasing curcumin concentrations. Therefore, pulpal paste with different nanocurcumin concentrations can be used considering the patient's age and the desired time of deciduous tooth loss, and dissolution of pulpal paste. Concerning the discoloration after 3 months, Metapex was the best material and the most discoloration rate was related to 20% CPP, and there was no difference between the 5% CPP, and 10% CPP with ZOE.

Bone Regeneration Effect of Nanochitosan with or without Temporally Controlled Release of Dexamethasone.

INTRODUCTION: Chitosan is a cationic biopolymer, and its modification as a nanoparticle as well as loading a corticosteroid on it may enhance its bone regenerative effect. The aim of this study was to investigate the bone regenerative effect of nanochitosan with or without dexamethasone. METHODS: Under general anesthesia, 4 cavities were created in the calvarium of 18 rabbits and filled with nanochitosan, nanochitosan with a temporally controlled release of dexamethasone (nanochitosan + dexamethasone), an autograft, or left unfilled (control). The defects were then covered with a collagen membrane. The rabbits were randomly divided into 2 groups and were sacrificed at 6 or 12 weeks after surgery. The new bone type, osteogenesis pattern, foreign body reaction, and the type and severity of the inflammatory response were evaluated histologically. The amount of new bone was determined using histomorphometry and cone-beam computed tomographic imaging. One-way analysis of variance with repeated measures was performed to compare results between the groups at each interval. A t test and chi-square test were also conducted to analyze changes in variables between the 2 intervals. RESULTS: Nanochitosan and the combination of nanochitosan and dexamethasone significantly increased the combination of woven and lamellar bone (P = .007). No sample showed a foreign body reaction or any acute or severe inflammation. Chronic inflammation was significantly decreased in number (P = .002) and severity (P = .003) over time. There was no significant difference between the extent and pattern of osteogenesis among the 4 groups, as evaluated by histomorphometry and cone-beam computed tomographic imaging at each interval. CONCLUSION: Nanochitosan and nanochitosan + dexamethasone were comparable with the gold standard of autograft regarding the type and severity of inflammation as well as the level and pattern of osteogenesis; yet, they induced more woven and lamellar bone.

Optic nerve head optical coherence tomography angiography findings in patients with thyroid eye disease: a case-control study.

BACKGROUND: To evaluate changes in the vessel density (VD) of the optic nerve head (ONH) microvasculature in thyroid eye disease (TED) using optical coherence tomography angiography (OCTA). This study aimed to applicate the OCTA as a noninvasive modality in screening TED patients to assess sub-clinical changes. METHODS: In a cross-sectional study, the control group patients were healthy individuals with no ocular abnormalities and were euthyroid. All patients with TED had clinical features of the disease. We divided them into two groups using the clinical activity score (CAS). Patients with CAS scores 0-2 were categorized as group A, and scores three or more as group B. All vessels (AV) and small vessels (SV) VD inside disc and radial peripapillary capillary network were measured using the ONH-OCTA. RESULTS: We evaluated 29 patients with TED and 28 healthy controls. The mean whole image AV VD (mean ± SD: 56.33 ± 2.56, p-value = 0.17) and the mean whole image SV VD (mean ± SD: 49.94 ± 2.56, p-value = 0.16) in the TED group had no statically significant difference compared with the control group (AV mean ± SD: 57.20 ± 20.22, SV mean ± SD: 50.84 ± 2.23). We found a non-significant decrease in AV and SV radial peripapillary capillary VD in the TED group. There was a significant decrease in the mean whole image AV VD (mean ± SD: 54.83 ± 3.07, p-value = 0.005) and the mean whole image SV VD (mean ± SD: 48.60 ± 3.18, p-value = 0.013) in CAS group B compared to group A (AV mean ± SD: 57.45 ± 1.33, SV mean ± SD: 50.95 ± 1.37). CONCLUSION: Our study showed non-significant ONH vascular alterations in patients with TED, including reduced VD of ONH in the radial peripapillary capillary. Patients with higher CAS scores had a more noticeable decrease in ONH microvasculature.

The Outcome of Endodontic Regeneration in a Delayed Replanted Immature Permanent Incisor: A TurboReg Analysis of a Case.

OBJECTIVES: The aim of this case report is to address a delayed replantation and successful regenerative endodontic procedure of an avulsed immature permanent incisor which was confirmed by TurboReg analysis. STUDY DESIGN: In this case, regenerative endodontic procedure was performed on an avulsed tooth with a delayed replantation in a 7 year old boy. In the emergency visit after the avulsion accident in February 2017, the tooth was replanted and one week later regenerative endodontic procedure began. After 17 months follow up, in July 2018, root wall thickness and length increase was confirmed by TurboReg analysis. CONCLUSION: The outcome of this treatment was evaluated by TurboReg analysis which was a remarkable increase in root length and dentinal wall thickness, despite of the delayed replantation. CLINICAL SIGNIFICANCE: This case report helps to add to the literature for treatment plan in avulsion traumatic injuries.

Preventive practice, vaccine acceptance, and knowledge toward coronavirus disease-19: An online cross-sectional questionnaire-based report in Iranian dentists.

BACKGROUND: The coronavirus disease (COVID) is predicted to cause serious mental health problems among healthcare providers (HCPs) especially dentists. Also understanding the influencing factors of the acceptance of COVID-19 vaccination among HCPs are important aspects in the design of effective strategies to improve the vaccine coverage rate. Therefore, this study aimed to assess the knowledge, vaccination acceptance, fear, and obsession, as well as the preventive practice behaviors of Iranian dentists and dental students in late 2020 toward COVID-19. MATERIALS AND METHODS: A descriptive, web-based cross-sectional survey was conducted among Iranian dental students and dentists (general practitioners and specialists). All Iranian dentists and dental students living in the Islamic Republic of Iran regardless of their city and workplace were invited to participate in the study. The total number of dentists in Iran was estimated to be 54,927. The sample size was calculated 380. The questionnaires used in this study were adapted from previously published studies based on the authors' permission. The questionnaire consisted of four sections that sought to collect information on the respondents' vaccination acceptance, knowledge, preventive practice, fear, and obsession toward COVID-19. The relationship between the study variables was assessed using Pearson's correlation coefficient and also multiple linear regression tests. RESULTS: Overall, 394 dentists were filled the questionnaire (65 dental students, 151 general dentists and 178 specialists). There were no differences in terms of vaccination acceptance, knowledge and also fear score in different designation groups. Dentists had significantly higher obsession and also preventive practice scores than other designation groups (P < 0.05). The majority of respondents had good knowledge (more than 9), acceptable preventive practice (more than 19), low fear-obsession (<2.7), and high acceptance of COVID-19 vaccination (more than 8.8). CONCLUSIONS: Although obsession and fear scores were low in all designation groups, dentists had higher obsession and also preventive practice scores than other designation groups. More than half of respondents preferred imported COVID-19 vaccines. Finally, organizations such as the World Health Organization and the Ministry of Public Health in Iran should increase vaccine convenience and accessibility in terms of vaccine importing, distribution, supply, and immunization service.

A Scoping Review of Four Decades of Outcomes in Nonsurgical Root Canal Treatment, Nonsurgical Retreatment, and Apexification Studies: Part 3-A Proposed Framework for Standardized Data Collection and Reporting of Endodontic Outcome Studies.

INTRODUCTION: Despite initiatives to standardize and improve reporting of rapidly growing endodontic outcome research studies, issues related to missing and ambiguous information are still of great concern. In this article, we propose a framework for standardized data collection and a compiled checklist for reporting of various study designs on endodontic outcome. METHODS: A comprehensive search was carried out to locate randomized controlled trials, cohorts, case-control studies, or case series of >100 patients that reported on endodontic outcomes. We reviewed these articles to develop a Data Collection Template and compiled a checklist for reporting of future endodontic outcome research. RESULTS: Out of 354 eligible articles previously reported in our scoping review on endodontic outcome studies, 109 articles were selected and screened for study variables or levels of categorization. Our complied Data Collection Template was developed in 19 domains to highlight important demographic, preoperative, intraoperative, and postoperative variables. Because of the specific needs for endodontic outcome literature, we also proposed a compiled checklist (consisting of 4 main domains) to facilitate the reporting of various study designs on endodontic outcome studies. This checklist included simple descriptions of the required items and examples on reporting from published endodontic studies. CONCLUSIONS: By facilitating the collection and reporting of relevant research data by investigators in private practice and academia, we hope that the proposed Data Collection Template and reporting guideline can highlight the importance of standardization among clinicians and researchers while producing valid scientific information that will support evidence-based treatment decisions.

A Scoping Review of 4 Decades of Outcomes in Nonsurgical Root Canal Treatment, Nonsurgical Retreatment, and Apexification Studies-Part 2: Outcome Measures.

INTRODUCTION: Inconsistencies in the definitions of endodontic outcome terminology jeopardize evaluations of proposed interventions and patient care quality. This scoping review aimed to provide groundwork to develop a set of basic outcomes in endodontics. METHODS: We performed a comprehensive literature search for randomized controlled trials, cohort studies, case-control studies, and case series (≥10 patients) published after 1980 with patients ≥10 years of age with any preoperative pulpal and periapical diagnosis in permanent teeth requiring nonsurgical root canal treatment, retreatment, or apexification. Abstracted data on outcome assessment methods, assessors, and domains were reported after univariate and bivariate analyses. RESULTS: Treatment outcomes were evaluated radiographically (88%) or clinically (73%). Although 2-dimensional radiography exceeded 3-dimensional radiography, the use of the latter has increased since 2010, mostly for nonsurgical retreatments. Of 19 identified outcomes, 5 were most frequent: success (168 studies, 40%), radiographic healing (128 studies, 30%), survival (of an asymptomatic tooth [48 studies, 12%] or of a procedure code in administrative databases [31 studies, 7%]), pain assessment (14 studies, 3%), and quality of life (11 studies, 3%). Clinician-centered outcomes have been most frequently studied since the 1980s (71%), in academic settings (76%), and using a prospective design (45%). Patient-centered outcomes were reported in 19% of studies before 2010 and 30% since 2010. They were more common among retrospective studies (49%). CONCLUSIONS: Patient-centered outcome measures are lacking in endodontic studies. The state of available research can provide a baseline for the development of a core outcome set in endodontics, which should represent the important patient-centered outcomes in conjunction with well-validated clinician-centered outcomes.

A Scoping Review of 4 Decades of Outcomes in Nonsurgical Root Canal Treatment, Nonsurgical Retreatment, and Apexification Studies-Part 1: Process and General Results.

INTRODUCTION: Despite initiatives to standardize reports, variances in study design, outcomes assessed, and tools used are persistent in the literature. This review scoped the existing literature on endodontic outcome studies for future development of core outcome sets. METHODS: A comprehensive literature search of randomized controlled trials, cohort studies, case-control studies, and case series (≥10 patients) published after 1980 including patients ≥10 years of age with any preoperative pulpal and periapical diagnosis in permanent teeth requiring nonsurgical root canal treatment (NS-RCT), retreatment (NS-ReTx), or apexification was performed. Abstracted data were reported through descriptive statistics. RESULTS: Of the 9957 studies screened, 354 were included. An increase in the quantity of endodontic outcome publications and levels of evidence in their study design was noted over the past 4 decades. Although 41% of the studies included participants 26-50 years of age, literature including participants >50 years old has increased since 2000. Apexification and NS-ReTx were mostly provided by specialists and postgraduate students. The most common follow-up period was 2-5 years (35%), and most randomized controlled trials (58%) reported follow-up times <1 year. Multiple-visit treatment was most common in apexification studies (85%). Deficiency, inconsistency, and ambiguity were observed across many reports. CONCLUSIONS: NS-ReTx and NS-RCT/NS-ReTx studies have increased over the past 2 decades, particularly those focusing on molars and patients >50 years old. Despite the progress in endodontic research, heterogeneity in reporting styles yields considerable limitations, particularly data standardization challenges and inconsistencies in methods and results reporting. This scoping review highlighted the state of available research and supported the development of standardized guidelines for future investigations.

Evaluation of the outcome of apexogenesis in traumatised anterior and carious posterior teeth using mineral trioxide aggregate: a 5-year retrospective study.

The purpose of this study was to evaluate the outcome of apexogenesis with mineral trioxide aggregate (MTA) in traumatised anterior and carious posterior teeth over 5 years. A comprehensive chart review was performed to obtain a retrospective of sequential previously completed cases with recalls. Clinical and radiographic data were collected for 97 vital immature teeth (40 traumatised anterior and 57 carious posterior teeth) pulpotomised (partial or full pulpotomy) using MTA with an average follow-up time of 5 years. Chi-squared test and Fisher's exact test were implemented to analyse data. The success rate in anterior teeth and posterior teeth was 82.5% and 96.4% respectively. Crown discolouration was observed in 25 (62.5%) anterior teeth. There was a significant difference between the number of successful and unsuccessful cases (P < 0.05) and there was no correlation between type of treatment and success/failure (P > 0.05). The success rate of apexogenesis using MTA in immature teeth was relatively high.

Intentional Replantation of a Mandibular Premolar as Treatment for Lower Lip Paresthesia: A Case Report.

Paresthesia can result from some post-endodontic problems, including bacterial infections or mishaps which occur during the cleaning, shaping, and filling of the root canal. There are pharmacological and instrumental methods for the treatment of paresthesia; however, if presenting symptoms are suggestive of nerve injury, surgical approaches, such as intentional replantation, could be considered. In this case report study, we treated paresthesia that had occurred after endodontic treatment using intentional replantation. This case report describes the use of intentional replantation of a mandibular premolar as a successful technique to treat paresthesia involving the lower lip.

Endodontic Management of a Maxillary Premolar with a Rare Configuration (Three Buccolingually Positioned Canals in a Single Root) as Confirmed by Cone Beam Computed Tomography: a Case Report.

Missed canals pose a potential risk in the treatment of teeth with anatomical variations, even when multi-angled radiographs have been used. Incomplete mechanical and chemical debridement of the root canal system can lead to treatment failure. Therefore, clinicians must have adequate knowledge of normal root canal systems as well as any possible variations in order to prevent any failure during or after the treatment of teeth with anatomical variations. Any case report of such rare variations would add to this critically required body of knowledge. The current case report presents the diagnosis and endodontic treatment of a maxillary first premolar with one root and three canals (one palatal and two buccal canals, all buccolingually positioned, bifurcating in the apical region), which was different from premolars with 3 canals reported up to now. This configuration describes an unusual root canal system for the maxillary first premolar and does not fit into any of the well-known root canal classification systems.

Treatment Outcomes of Permanent Immature Teeth with Crown Fracture: A Retrospective Cohort Study.

INTRODUCTION: Crown fractures are a common type of traumatic dental injury. Various factors may affect the outcome of crown fractures. This study aimed to evaluate the treatment outcomes of immature teeth with a crown fracture. METHODS: This retrospective cohort study included patients who presented to a dental trauma center from 2008-2018 with a history of a crown fracture of immature teeth and at least 6 months of follow-up. Outcomes of primary endodontic or restorative interventions as well as reinterventions were evaluated. Kaplan-Meier curves were used to compare the unadjusted differences in survival time. Logistic and Cox regression analyses were performed to identify potential predictors for complication and survival time, respectively. RESULTS: The success rates of the primary interventions for 99 teeth (72 patients) after a median follow-up of 22 months were as follows: cervical pulpotomy (90.4%), partial pulpotomy (85.2%), mineral trioxide aggregate apical barrier (80.0%), root canal treatment (66.6%), and only restoration (47.2%). Teeth that received vital pulp therapy were less prone to complications (adjusted hazard ratio = 0.21; 95% confidence interval, 0.09-0.53; P < .05), whereas those with concomitant luxation injuries were more susceptible to complications (adjusted odds ratio = 2.90; 95% confidence interval, 1.01-8.29; P < .05). CONCLUSIONS: Crown fractures had a relatively high favorable prognosis. Vital pulp therapy (partial or cervical pulpotomy) had the highest success rate, whereas cases that received only restoration had the lowest success rate. Teeth with concomitant luxation injuries had more odds and hazards of complications.

Evaluating Vitality and Sensitivity of Teeth Adjacent to the Site of Closed Sinus Lift Surgery before and after Treatment.

The aim of this study was to evaluate the effect of closed sinus lift surgery on dental vitality and periodontal sensitivity of teeth adjacent to the surgery area. Thirty patients undergoing closed sinus lift surgery by osteotomes were evaluated for dental vitality and periodontal sensitivity of adjacent teeth. Dental vitality and sensitivity were evaluated using the electric pulp tester (EPT) and cold spray once before surgery and one week, one month, and six months after surgery. In order to increase the validity of the study, one contralateral tooth in each patient was considered the control. In the test group, the number of teeth that did not respond to EPT and cold stimuli increased from baseline to six months after surgery and showed a significant difference between the four time intervals (P = 0.015 for EPT; P = 0.007 for cold stimuli). Thus, the vitality of teeth adjacent to the closed sinus lift area was lost over time. There was no significant difference between the two groups at any time for either stimuli. According to this research, tooth sensitivity to EPT and cold stimuli was not significantly different between test subjects and controls. For both cold and electrical stimulation, the number of teeth that did not respond was highest at one week after surgery and significantly different from baseline. However, after six months postsurgery, this number decreased, indicating recovery. However, some teeth were considered necrotic in the sixth month. It can be concluded that closed sinus lift surgery may cause necrosis in adjacent teeth, but more studies are required.

Clinical comparison of sensitivity and specificity between sensibility and vitality tests in determining the pulp vitality of mandibular premolars.

This clinical study was designed to compare cold pulp testing (CPT), heat pulp testing (HPT) and electric pulp test (EPT) with pulse oximetry (PO), flowmetry (FM) and thermometry (TM) in terms of sensitivity and specificity. Twenty premolar teeth in need of root canal treatment were included in the study. Pulp sensibility tests (CPT, HPT and EPT) along with vitality tests (PO, FM and TM) were performed. As the gold standard, the teeth were endodontically treated and pulp vitality was determined by direct visual observation. Sensitivity, specificity and accuracy values for each test were as follows: HPT 1, 1, 100%; CPT 1, 0.818, 90%; EPT 1, 0.909, 95%; PO 1, 0.545, 75%; TM 0.111, 0.272, 20%; and FM 0.444, 0.272, 35%, respectively. The most accurate test among all was HPT. PO was the most accurate vitality test.

Does dental fluorosis affect electric pulp test response and/or optimum probe placement site?

The placement site of electric pulp tester (EPT) probe on the tooth affects the threshold values obtained. The aim of this study was to determine and compare threshold levels and appropriate placement sites for EPT probe on fluorotic and normal teeth. Equal numbers of fluorotic and non-fluorotic maxillary central incisors of 40 subjects were assessed. The mean of three threshold readings from an EPT was taken from the labial surface at the incisal edge, incisal third, middle third and cervical third. Kruskal-Wallis and Friedman ANOVA followed by post hoc tests were used to compare threshold scores. Significantly higher thresholds were recorded for fluorotic teeth at the incisal edge and incisal third. The lowest thresholds were obtained for the incisal edge in both fluorotic and non-fluorotic teeth when compared to the cervical third. There was no statistically significant difference among corresponding test sites between the genders and age groups.

Does the application of GaAlAs laser and platelet-rich plasma induce cell proliferation and increase alkaline phosphatase activity in human dental pulp stem cells?

Blood extracts containing platelet products are gaining popularity in promoting healing and pulp regeneration. This study was designed to evaluate the effect of platelet-rich plasma (PRP) and gallium-aluminum-arsenide (GaAlAs) laser on proliferation and differentiation of human dental pulp stem cells (hDPSCs). In this ex vivo study, hDPSCs isolated from impacted mandibular third molars were cultured in Dulbecco's Modified Eagle's medium )DMEM(with 10% fetal bovine serum (FBS). After reaching the desired confluence, the cells were distributed into 4 groups, namely, control, PRP, laser, and PRP+laser for MTT assay and alkaline phosphatase (ALP) test. In the PRP and PRP+laser groups, 10% PRP was added to each well on the plate. In the laser and PRP+laser groups, as for the proliferation test, laser irradiation was carried out for 45 s, while 135 s was designated for ALP test. After 1, 3, and 5 days, cell proliferation and ALP activity were assessed using MTT and ALP colorimetric assay, respectively. Two-way ANOVA was utilized to analyze data. In PRP and PRP+laser groups, cell proliferation and viability increased until day 3 but began to decline afterwards until the 5th day. In the laser group, the increase in proliferation and viability was observed till day 5 which was less than the control group. Laser and control groups exhibited significantly higher cell viability and proliferation than both PRP and PRP+laser groups. ALP activity was more pronounced in PRP+laser, PRP, and laser in descending order; however, all were less than that of the control group. Only in the control group did the ALP activity augment during the 5-day period. Laser irradiation could induce pulp cell proliferation and demonstrated a better performance than PRP in this regard.

Endodontic Treatment of C-shaped Mandibular Premolars: A Case Report and Review of Literature.

Our article aimed to present a curious case of a mandibular premolar with a C-shaped root canal and to review the available literature on this anatomical variation. Mandibular premolar teeth account for the greatest endodontic challenges in the course of treatment on account of the morphological variations in their root canal systems, including extra root(s)/canal(s) or a C-shaped configuration. A 20-year-old female patient was referred to the Department of Endodontics of Mashhad Faculty of Dentistry, suffering from abscess, and pain while chewing. On examination the culprit was found to be the left mandibular first premolar. Following special tests and periapical radiography, we found an amalgam restoration proximate to the non-vital pulp chamber, as well as an unusually complex root canal anatomy with periapical radiolucency. A non-surgical root canal treatment with the aid of a dental operating microscope was considered as the treatment plan. Clinicians should always anticipate the presence of a C-shaped configuration in mandibular premolars, and make use of all the available tools to locate and treat such cases. A substantial knowledge of root canal anatomy would be prudent to ensure a successful outcome ensuing surgical and non-surgical root canal treatments.