Pulp Tissue Research Articles

Histological Evaluation of Polyacid-Modified Composite Resin and Conventional Composite Resin Used for Primary Molars Restoration

Background: The present study evaluated the histological outcomes of two dental restorative materials, polyacid-modified composite resin (compomer) and conventional composite resin, in the primary molars of puppies. Materials and Methods: Twenty sound primary molars in four puppies were used. The puppies were rendered unconscious using general anesthesia. Similar cylindrical Class V cavities were prepared in 16 of the 20 selected primary molars. The teeth were divided into three groups: Group I: Eight cavities were restored with compomer; Group II: Eight cavities were restored with conventional composite resin; Group III: Four teeth remained untreated and were used as controls. In Groups I and II, four teeth were examined histologically after 2 weeks and the other four after 6 weeks. The histological findings were analyzed and compared to determine the effects of each type of resin material on the dentine and the pulp. Results: At 6 weeks, the specimens tested for compomer showed obvious destructive changes in the central region and the region of the pulp adjacent to the cavity. The specimens tested for conventional composite resin revealed, at 6 weeks, massive destruction of the pulp tissues and abscess formation was observed. All the specimens tested in the control group showed normal cellularity, normal vascularity, and proper alignment of odontoblast cells. Conclusions: The teeth restored with compomer demonstrated more favorable pulpal reactions when compared with the teeth restored with conventional composite resin after 6 weeks.

Preparation and characterization of bovine dental pulp-derived extracellular matrix hydrogel for regenerative endodontic applications: an in vitro study

BackgroundThe use of biological scaffolds in regenerative endodontics has gained much attention in recent years. The search for a new biomimetic scaffold that contains tissue-specific cell homing factors could lead to more predictable tissue regeneration. The aim of this study was to prepare and characterize decellularized bovine dental pulp-derived extracellular matrix (P-ECM) hydrogels for regenerative endodontic applications.MethodsFreshly extracted bovine molar teeth were collected. Bovine dental pulp tissues were harvested, and stored at -40º C. For decellularization, a 5-day protocol was implemented incorporating trypsin/EDTA, deionized water and DNase treatment. Decellularization was evaluated by DNA quantification and histological examination to assess collagen and glycosaminoglycans (GAGs) content. This was followed by the preparation of P-ECM hydrogel alone or combined with hyaluronic acid gel (P-ECM + HA). The fabricated scaffolds were then characterized using protein quantification, hydrogel topology and porosity, biodegradability, and growth factor content using Enzyme-linked immunosorbent assay (ELISA): transforming growth factor beta-1(TGF-β1), basic fibroblast growth factor (bFGF), bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF).ResultsDecellularization was histologically confirmed, and DNA content was below (50 ng/mg tissue). P-ECM hydrogel was prepared with a final ECM concentration of 3.00 mg/ml while P-ECM + HA hydrogel was prepared with a final ECM concentration of 1.5 mg/ml. Total protein content in P-ECM hydrogel was found to be (439.0 ± 123.4 µg/µl). P-ECM + HA showed sustained protein release while the P-ECM group showed gradual decreasing release. Degradation was higher in P-ECM + HA which had a significantly larger fiber diameter, while P-ECM had a larger pore area percentage. ELISA confirmed the retention and release of growth factors where P-ECM hydrogel had higher BMP-2 release, while P-ECM + HA had higher release of TGF-β1, bFGF, and VEGF.ConclusionsBoth P-ECM and P-ECM + HA retained their bioactive properties demonstrating a potential role as functionalized scaffolds for regenerative endodontic procedures.

Bovine pulp extracellular matrix hydrogel for regenerative endodontic applications: in vitro characterization and in vivo analysis in a necrotic tooth model

BackgroundRegenerative endodontic procedures (REPs) offer the promise of restoring vitality and function to a previously necrotic and infected tooth. However, the nature of regenerated tissues following REPs remains unpredictable and uncontrollable. Decellularized extracellular matrix scaffolds have gained recent attention as scaffolds for regenerative endodontics.ObjectivesPreparation and characterization of a bovine dental pulp-derived extracellular matrix (P-ECM) hydrogel for regenerative endodontic applications. Biocompatibility and regenerative capacity of the prepared scaffold were evaluated in vivo in a canine animal model.MethodsFifteen freshly extracted bovine molar teeth were used to prepare P-ECM hydrogels following approval of the institutional review board of the faculty of dentistry, Alexandria University. Decellularization and lyophilization of the extracted pulp tissues, DNA quantification and histological examination of decellularized P-ECM were done. P-ECM hydrogel was prepared by digestion of decellularized pulps. Prepared scaffolds were evaluated for protein content and release as well as release of VEGF, bFGF, TGF-β1 and BMP2 using ELISA. Rabbit dental pulp stem cells’ (rDPSCs) viability in response to P-ECM hydrogels was performed. Finally, proof-of-concept of the regenerative capacity of P-ECM scaffolds was assessed in an infected mature canine tooth model following REPs versus blood clot (BC), injectable platelet-rich fibrin (i-PRF) or hyaluronic acid (HA). Statistical analysis was done using independent t test, the Friedman test and chi-square tests (p value ≤ 0.05).ResultsDNA was found to be below the cut-off point (50 ng/mg tissue). Histological evaluation revealed absence of nuclei, retention of glycosaminoglycans (GAGs) and collagen content, respectively. P-ECM hydrogel had a total protein content of (493.12 µg/µl) and protein release was detected up to 14 days. P-ECM hydrogel also retained VEGF, bFGF, TGF-β1 and BMP2. P-ECM hydrogel maintained the viability of rDPSCs as compared to cells cultured under control conditions. P-ECM hydrogel triggered more organized tissues compared to BC, i-PRF and HA when used in REPs for necrotic mature teeth in dogs. Periapical inflammation was significantly less in HA and P-ECM groups compared to blood-derived scaffolds.ConclusionBovine dental pulp-derived extracellular matrix (P-ECM) hydrogel scaffold retained its bioactive properties and demonstrated a promising potential in regenerative endodontic procedures compared to conventional blood-derived scaffolds.

Efficacy of vital pulp therapy for carious pulp injury in permanent teeth: a study protocol for an open-label randomized controlled noninferiority trial.

Vital pulp therapy (VPT) has recently been reported as an effective approach for preventing and treating carious pulp injury in permanent teeth. Compared with root canal treatment (RCT), which involves complete removal of the pulp tissue, VPT effectively maintains pulp vitality and retains the physiological functions of the pulp. In the research pool, large-scale randomized controlled trials evaluating the treatment outcome of VPT using calcium silicate cements and RCT in cariously exposed permanent teeth are lacking. Here, we present a monocentric clinical protocol to compare the effects of VPT using iRoot BP Plus (Innovative Bioceramix, Vancouver, BC, Canada) as a pulp-capping material with RCT. The proposed trial is an open-label, single-centre, randomized, controlled, noninferiority trial. In total, 462 patients will be included in this trial according to the following criteria: adult patients (18-50years old), pulp exposure during the treatment of deep caries in mature permanent teeth, a diagnosis of reversible or partially irreversible pulpitis without apical translucency on X-ray, without periodontitis or systemic disease. Patients with signed informed consent forms will be enrolled and randomly divided into two groups (VPT and RCT) with a balanced treatment allocation (1:1). Clinical evaluations will be conducted at baseline and at 3, 6, 12, and 24months after treatment, with the potential for extension. The primary outcome measure will be the duration of success. The secondary outcomes will include the success rate at the 1-year follow-up and any adverse reactions. The Kaplan‒Meier method and log-rank test will be used to compare the duration of success of both treatments. For other outcomes, the χ2 test or Fisher's exact test will be used for categorical variables, and the t test or Mann‒Whitney U test will be used for continuous variables to assess the differences between groups. The results of this trial will provide a clinical reference for selecting treatments for carious pulp injuries in permanent teeth. ClinicalTrials.gov ChiCTR2100051369. The study has been registered in the Chinese Clinical Trial Registry (ChiCTR) ( www.chictr.org.cn ). Registered on 21 September 2021.

Evaluation of hard tissue characteristics and calcifications in pulp tissue of hypomineralized permanent molars using micro-computed tomography

ObjectivesTo determine and compare pulp volume, dentin mineral density, presence of microcracks, pulp stones, and accessory canals, as well as their localizations in root regions for hypomineralized and healthy teeth. DesignThis study included 60 extracted permanent molar teeth, categorized into hypomineralized and healthy groups (n = 30 each). The hypomineralized group comprised molar teeth with limited white, yellow, or brown opacities, post-eruptive breakdown, or extensive restoration or crown damage. The healthy group included caries-free molar teeth without these characteristics. Using 3D micro-computed tomography images pulp volume, dentin mineral density, and the presence and locations of microcracks, pulp stones, and accessory canals were determined for each group. Statistical analyses were conducted using Independent T-test and Chi-square test, with significance set at p < 0.05. ResultsThere was no statistically significant difference between the groups regarding pulp volume and microcracks (p ≥ 0.05). The number of accessory canals was significantly greater in the cervical (p = 0.011; p < 0.05) and middle (p = 0.010; p < 0.05) regions of the hypomineralized teeth than healthy teeth. Dentin mineral density was statistically higher in the apical, middle, and cervical root regions (p < 0.001; p < 0.05); however, the number of pulp stones was found to be greater in the cervical regions of healthy teeth compared with those with hypomineralization (p = 0.026; p < 0.05). ConclusionThere were lower dentin mineral density measurements, a decreased number of pulp stones in the cervical region, and a greater number of accessory canals in the middle and cervical regions of hypomineralized teeth compared with healthy teeth.

Total Pulpotomy with MTA in Young Permanent Teeth: Case Series

Vital pulp therapy is a way to preserve the vitality and function of pulp damaged by trauma, caries or restorative procedures. Vital pulp therapy procedures include direct pulp capping, indirect pulp capping, partial and coronal pulpotomy treatments where diseased pulp tissue is removed. Over the years, the focus of vital pulp therapy has been on the preservation of the radicular pulp in immature permanent teeth to ensure the completion of root formation (apexogenesis). Today, it has been reported that vital pulp therapy can be considered as an alternative to root canal treatment, including in teeth with certain conditions that are considered to have irreversibly inflamed pulp. Coronal amputation therapy, a vital pulp treatment, involves complete removal of the coronal pulp, placement of a biologically acceptable material into the pulp chamber and restoration. The covering material must be able to relieve inflammation and initiate healing of the pulp tissue and allow new dentin tissue to form. The oldest material used in pulpotomy is calcium hydroxide. Mineral trioxide aggregate, which is a more recent material, is frequently preferred today due to its biocompatible and bioactive properties. In this case report, the results of 4 cases of coronal pulpotomy with mineral trioxide aggregate in young permanent teeth with a follow-up of 18 months are presented.

Efficacy of proinflamatory cytokines in the clinical and radiograpic outcomes of different primary molar pulpotomy agents: a comperative randomised study featuring a novel biomarker for pulpal diagnosis

BackgroundWhile the effect of biomaterials covering the pulp tissue is considered in the success of pulpotomy treatment, the level of pulpal inflammation is still very important for treatment success. The aim of this study was to compare IL-6 and IL-8 levels, known as good indicators of pulpal inflammation, with a new biomarker, presepsin, and to evaluate the impact of biomarker levels along with the pulp capping agents used in the treatment on the one-year success of pulpotomy treatment.MethodsThe study included 120 primary second molar teeth with pulpotomy indications from 75 children. To determine the pulpal inflammation status, pulpal bleeding samples were taken during treatment, and the levels of IL-6, IL-8, and presepsin were measured. During the pulpotomy treatment, MTA, NeoMTA™, and Biodentine™, and ZOE were randomly applied to groups of thirty teeth each. Patients were monitored for a period of 12 months post-treatment.ResultsIL-8, IL-6, and presepsin levels were significantly higher in teeth with pathology (p < 0.001). Biomarker levels were found to be higher in the NeoMTA and Biodentine groups, but this did not result in a statistically significant difference. (p > 0.05) Following pulpotomy treatment, the most successful material groups in order were MTA, ZOE, NeoMTA™, and Biodentine™.ConclusionPresepsin may be a usable indicator in predicting the level of inflammation. At the end of the one-year follow-up of pulpotomy treatment, more pathology was observed in the NeoMTA and Biodentine groups, where biomarker levels were higher, while no pathology was found in the MTA group, where biomarker levels were lower.Trial registrationNCT06398327/ 20,240,503.

Integrating Phosphate Enhances Biomineralization Effect of Methacrylate Cement in Vital Pulp Treatment with Improved Human Dental Pulp Stem Cells Stimulation.

Vital pulp treatment (VPT) is crucial for preserving the health and function of the tooth in cases where the pulp tissue remains vital despite exposure. Various materials are introduced for this purpose. However, challenges such as low strength, high solubility, and tooth discoloration persist. Methylmethacrylate-based cement (MC) offers excellent sealing ability, feasibility, and mechanical properties, making it a promising alternative for VPT. Phosphate-based glass (PBG) has the potential to promote hard tissue regeneration by releasing key inducers, phosphorus (P) and calcium (Ca), for reparative odontogenesis. This study investigates PBG-integrated MC (PIMC) by characterizing its properties, assessing human dental pulp stem cell activity related to initial inflammatory adaptation and odontogenic differentiation, and evaluating hard tissue formation using an in vivo dog pulpotomy model. Results indicate that a 5% PBG-integrated MC (5PIMC) maintains the physicochemical properties of MC. Furthermore, 5PIMC demonstrates cytocompatibility, excellent expression of osteo/odontogenic markers, and resistance to inflammatory markers, significantly outperforming MC. Enhanced hard tissue formation is observed in the dental pulp of mongrel dog teeth treated with 5PIMC. These findings suggest that 5PIMC could be an optimal and suitable material for reparative odontogenesis through VPT.

Tri-Lineage Differentiation Potential of Stem Cells from Human Exfoliated Deciduous Teeth - An In-Vitro Study

ABSTRACT Background: The use of SHED might bring advantages for tissue engineering over the use of stem cells from adult human teeth as SHEDs were reported to have higher proliferation rate and increase cell population doublings as compared with stem cells from permanent teeth. Objective: The study’s objective was to assess the growth kinetics and tri-lineage differentiation capacity of stem cells derived from human exfoliated deciduous teeth. Material and Method: After being propagated through multiple sequential subcultures, adherent fibroblastic cells in the pulp tissue culture from human exfoliation teeth were evaluated to assess their tripotent differentiation potential into bone, cartilage, and adipose cell lineages. Result: The stem cells derived from dental pulp had a comparatively high ability for proliferation and successfully differentiated into chondrocytes and osteocytes while less significant for adipocytes. Conclusion: Stem cells from Human Exfoliated Deciduous teeth are mesenchymal stem cells which are multipotent and can serve as a promising incentive for therapeutic and future research purposes.

Melanoma-inhibiting activity promotes the migration and odontoblastic differentiation of stem cells of apical papilla

ObjectiveMelanoma Inhibitory Activity (MIA) has been predominantly studied in the context of melanoma and cartilage development. However, its role in dental pulp development and stem cell behavior remains largely unexplored. This study investigates the expression pattern of MIA in dental pulp tissues and its potential role in the proliferation, migration, and odontoblastic differentiation of stem cells from the apical papilla (SCAPs). Design:MIA expression in human pulp tissue was demonstrated by immunohistochemistry. SCAPs were cultured in normal and mineralization induction media, with MIA levels monitored via RT-qPCR and Western blot. Cell proliferation was evaluated using the CCK8 assay, while transwell and cell scratch assays were conducted to examine cell migration. The effect of MIA on odontoblastic differentiation was examined by qRT-PCR, Alkaline phosphatase activity assay, and Western blot. siRNA was used to knock down MIA to investigate its effect. A mouse subcutaneous implantation model was used to assess whether MIA promotes odontoblastic differentiation in vivo. Results:MIA expression was observed in the papilla and odontoblasts layer of the developing pulp. In vitro, MIA expression increased during SCAPs differentiation and was found to significantly enhance migration, and odontoblastic differentiation but not proliferation. Gene knockdown experiments confirmed MIA’s pivotal role in promoting SCAPs migration and differentiation. In vivo, MIA facilitated the formation of dentin-like structures and enhanced pulp-dentin complex regeneration. Conclusion:MIA plays a crucial role in SCAPs’ migration and differentiation, suggesting its potential application in pulp-dentin regeneration therapies. Further studies are required to fully elucidate the underlying mechanisms.

Regenerative Endodontic Procedures With Minced Pulp Tissue Graft in Mature Permanent Teeth: A Clinical Study

IntroductionRegenerative endodontic procedures (REPs) using cell-based approaches have emerged as novel treatment modalities. This clinical study aimed to present the outcomes and explore factors influencing REPs with minced pulp tissue (MP) grafts in a mature tooth. MethodsSix healthy male patients aged 20–27 requiring nonsurgical root canal treatment were enrolled in this study. MP tissue obtained from third molars was introduced into the instrumented, disinfected, and blood-filled root canal. The canal was sealed with bioceramic cement, and the coronal access cavity was restored. ResultsFollow-ups for 6 cases ranged from 19 to 42 months. Radiographically, all the teeth showed favorable outcomes. Among the 6 teeth, 2 showed neither intracanal calcification nor recovery in sensibility tests, and one had no intracanal calcification with an inapplicable sensibility test evaluation. In 2 teeth, intracanal calcification was observed in the apical third; however, there was no recovery in the sensibility tests. One tooth exhibited intracanal calcification in the apical third and showed recovery in the sensibility tests. Considering these outcomes and clinical variables, the size of the apical foramen and the composition of the transplanted pulp tissue were identified as tentative influencing factors. ConclusionsThis study on simplified cell-based therapy using autologous MP for pulp/dentin regeneration in adult teeth not only enhances our understanding of REPs but also suggests its potential as an alternative treatment option to conventional endodontic treatment.

Effect of lateral extent of pulp tissue removal on the outcome of partial pulpotomy for managing cariously exposed mature permanent molars with symptomatic irreversible pulpitis: A randomized clinical trial.

The aim of this study is to compare the outcomes of restricted partial pulpotomy (R-PP) versus extended partial pulpotomy (E-PP) for managing cariously exposed mature permanent molars with symptomatic irreversible pulpitis (SIP). This double-arm, parallel designed randomized clinical trial was registered at clinicaltrials.gov (registration number: NCT05406557). Following random allocation, 43 participants of each group received the designated intervention. In the R-PP group, 2-3 mm of superficial pulp tissue was removed only from the exposure site, while chamber was completely de-roofed and 2-3 mm of superficial pulp tissue from entire chamber was removed in the E-PP group. Haemostasis was achieved using 3% sodium hypochlorite-soaked cotton pellets. Upon haemostasis, ProRoot mineral trioxide aggregate (ProRoot MTA) was placed over the pulpal wound, overlaid with a resin-modified glass ionomer liner, and restored with composite resin in the same visit. Outcome measures included clinical and radiographic success evaluation at 6 and 12 months, and pain assessment using the visual analogue scale pre-operatively and daily for 7 post-operative days. Nonparametric tests were used for variables including patient's age, pain intensities, mean analgesic consumption, and haemostasis time. Categorical variables including gender, caries type, analgesic intake, hard tissue barrier formation, clinical and radiographic success, and pulp sensibility responses were assessed using Chi-square or Fisher's exact test. Tooth survival was analysed using Kaplan-Meier analysis. A total of 81 cases were analysed at 12 months follow-up. Comparable success was observed in both groups (97.6% in E-PP & 97.5% in R-PP; p > .05). The R-PP group reported significantly lower pain scores on the 1st and 2nd post-operative days than E-PP (p < .05) and required significantly less analgesic intake (p < .05). Hard tissue barrier formation was significantly lower in the R-PP group (p < .05). No significant differences were observed between groups regarding haemostasis time, pulp sensibility responses, and tooth survival (p > .05). Both the PP approaches exhibited comparable success for managing cariously exposed mature permanent molars with SIP. Given the conservative nature of R-PP, it may be used as preferred PP approach for managing such cases. Being the first study of this kind, further work is necessary to draw definitive conclusions.

Decellularized extracellular matrix derived from dental pulp stem cells promotes gingival fibroblast adhesion and migration

BackgroundDecellularized extracellular matrix (dECM) has been proposed as a useful source of biomimetic materials for regenerative medicine due to its biological properties that regulate cell behaviors. The present study aimed to investigate the influence of decellularized ECM derived from dental pulp stem cells (DPSCs) on gingival fibroblast (GF) cell behaviors. Cells were isolated from dental pulp and gingival tissues. ECM was derived from culturing dental pulp stem cells in growth medium supplemented with ascorbic acid. A bioinformatic database of the extracellular matrix was constructed using Metascape. GFs were reseeded onto dECM, and their adhesion, spreading, and organization were subsequently observed. The migration ability of the cells was determined using a scratch assay. Protein expression was evaluated using immunofluorescence staining.ResultsType 1 collagen and fibronectin were detected on the ECM and dECM derived from DPSCs. Negative phalloidin and nuclei were noted in the dECM. The proteomic database revealed enrichment of several proteins involved in ECM organization, ECM–receptor interaction, and focal adhesion. Compared with those on the controls, the GFs on the dECM exhibited more organized stress fibers. Furthermore, cultured GFs on dECM exhibited significantly enhanced migration and proliferation abilities. Interestingly, GFs seeded on dECM showed upregulation of FN1, ITGB3, and CTNNB1 mRNA levels.ConclusionsECM derived from DSPCs generates a crucial microenvironment for regulating GF adhesion, migration and proliferation. Therefore, decellularized ECM from DPSCs could serve as a matrix for oral tissue repair.

Nail Reconstruction Using an Osteo-onychocutaneous Flap with the Dorsal Digital Artery of the Hallux as the Pedicle: Techniques and Anatomical Insights

Nail reconstruction with preserved pulp tissue can be challenging due to the use of oversized flaps and nail deformities often resulting from bone resorption. This study describes a novel technique using the dorsal digital artery of the hallux as a pedicle for an osteo-onychocutaneous flap. A preoperative handheld Doppler was used to identify the course of the dorsal digital artery, and intraoperatively, the flap was elevated without disturbing the plantar tissue, thereby minimizing the risk of foot complications. A prospective study was conducted on all partial toe transplantation cases between September 2020 and March 2023 to analyze the anatomical variations of the dorsal digital artery. Thirty-one patients were included in the study. The dorsal digital artery was successfully identified preoperatively and confirmed intraoperatively in all cases. It branched from the first dorsal metatarsal artery in 24 cases and from the plantar digital artery in seven cases. The branching location was found to be 24.3 ± 4.5mm proximal to the web in the former group and 3.9 ± 3.9mm (p < 0.001) in the latter group. The vascular diameter at the branching site was measured to be 0.8 ± 0.2mm, with no significant difference based on the location. Nail reconstruction procedures were successfully performed using this flap for defects in the thumb, index finger, and little finger. Stable nails were reconstructed in all cases with minimal foot complications. In conclusion, this technique offers a reliable approach to nail reconstruction, minimizing donor site morbidity and preserving natural nail morphology.

Surgical Endodontic Management Of Maxillary Incisors: A Case Report

In the root canal system, infection of the pulp tissue caused by caries or other pathways is the primary cause of apical periodontitis. The ultimate goal of the endodontic treatment is to create adequate conditions for periradicular tissue healing. Nonsurgical endodontic treatment is a highly predictable treatment option in most cases, but surgery may be indicated for teeth with persistent periradicular pathosis unresponsive to nonsurgical approaches. The aim of this article is to highlight the possibility of the successful outcome of surgical endodontic treatment following failed non-surgical treatment of right maxillary central incisor. With proper case selection and operator skill, periradicular surgery can be considered predictable, cost-effective alternative to tooth extraction and tooth replacement.

Investigation of Apoptosis in Healthy and Inflamed Pulp Tissue

Investigation of Apoptosis in Healthy and Inflamed Pulp Tissue

Non-Surgical Endodontic Management of Teeth with Aberrant Anatomy: A Case Series

The root canal therapy aims to remove the necrotic and vital pulp tissue remnants from the root canal to treat the periradicular inflammation. The knowledge of the tooth anatomy is essential to ensure a successful treatment. However, the deviation of the tooth anatomy complicates the diagnostic and treatment processes. Effective management of such complexities requires a tailored approach, utilizing detailed imaging and precise endodontic techniques to achieve successful outcomes and restore patient function and comfort. This case series presents the endodontic management of three different anatomic variations of permanent teeth that include taurodontism in the mandibular molar, two rooted mandibular canine and dilacerated maxillary central incisor and underscores the importance of personalized treatment planning and advanced diagnostic tools in managing complex dental anomalies.

The construction of an inflammation classification model for HDPCs applied in guiding pulpotomy based on single-cell Raman spectroscopy

The immune defense and the repair function of the pulp tissue serve as the biological foundation of pulpotomy. The precise evaluation of the pulp inflammation extent and determining its reversibility are essential for the success of pulpotomy. The objective of this study was to classify the molecular-level of dental pulp cell physiology and inflammatory state based on the biochemical changes obtained by single-cell Raman spectroscopy. Firstly, we differentiated the growth of HDPCs (human dental pulp cells) under physiological states by employing Raman spectroscopy with multivariate statistical analysis. Raman spectroscopy reflected the biochemical changes at different growth phases, including the lag phase, log phase, and stationary phase. Secondly, we evaluated the optimal concentration and duration of Porphyromonas gingivalis lipopolysaccharide (P.g.LPS) stimulation to establish a six-level inflammation classification model of HDPCs. Thirdly, we performed label-free characterization of biological component changes in cells of different inflammation grades by Raman spectroscopy. As a result, the differences of peaks in the region 600–1800 cm−1 demonstrated the biochemical molecular alterations in the different inflammation grades of HDPCs. As inflammation progresses in steps, protein peaks increased first and then decreased, while lipid and nucleic acid peaks gradually decreased compared to unstimulated cells. However, when the inflammatory stimulation reached grade V, the changes in the biological properties were characterized by a recovery in protein and lipid content, and a decrease in nucleic acid content. We then established the diagnostic model using the Raman spectra of HDPCs in physiological and inflammatory states, which had a prediction accuracy of 100 % and 97.4 %, respectively. Finally, we determined the reversibility threshold of HDPCs at different grades of inflammation. We observed that the inflammation of grade I and II cells had potential reversibility and could be attempted to be retained. In conclusion, Raman spectroscopy combined with multivariate statistical analysis has potential possibility to effectively distinguish the degree of inflammation in the dental pulp, thus providing new tools and perspectives on pulpotomy in clinical practice.

Hospital Visits Associated With Oral Infections in Patients With Neurofibromatosis Type 1: A Register-Based Analysis.

Various forms of oral involvement have been reported in patients with neurofibromatosis 1 (NF1). Here, we analyze register-based associations between NF1 and hospital visits related to oral infections. The Finnish NF1 cohort encompasses all individuals with verified NF1 who have visited the Finnish central and university hospitals in 1987-2011. The Finnish Care Register for Health Care allowed the follow-up of 1349 individuals with NF1, their 1894 siblings without NF1, and 13,870 matched controls for diagnoses related to oral infections in 1998-2014. We observed clearly increased hazards for hospital visits associated with dental caries (ICD-10 K02; NF1 vs. controls, hazard ratio [HR] 4.42, 95% CI 3.23-6.04), diseases of pulp and periapical tissues (K04; HR 3.85, 95% CI 2.68-5.54), and gingivitis and periodontal diseases (K05; HR 3.63, 95% CI 2.37-5.56). In contrast, hospital visits related to diseases of salivary glands (K11), and stomatitis and related lesions (K12) did not show significantly increased hazard in NF1 compared with the controls or the non-NF1 siblings. In conclusion, the findings suggest that hospital visits related to oral infections are relatively common among individuals with NF1. The results highlight the need for early detection, proactive prevention, and timely treatment of oral infections in individuals with NF1.

Assessment of Risk Factors and Prognostic Predictors for Endo-Perio Lesions in Indian Cohorts: An Observational Study.

Endodontic and periodontal tissues exhibit a significant interrelationship, whereby pathologies affecting one tissue can precipitate the involvement of the other. The primary objective of this study was to assess the risk factors associated with endo-perio lesions (EPLs). The secondary objective was to assess the prognostic predictors for such lesions and the prevalence rate of EPLs involving both pulpal and periodontal tissues in Indian cohorts. A prospective observational study was conducted on 2170 teeth with EPLs in Indian adults aged > 18 years. A detailed history of smoking, tobacco chewing, and the development of EPLs was obtained from all patients. Detailed periodontal and endodontic examinations were conducted by two calibrated examiners. Intraoral periapical radiographs (IOPAs) were obtained to diagnose EPLs. The chi-square test of association was used to analyze the association between independent and dependent variables, and the strength of association was presented by Pearsoncontingency coefficient (r). Logistic regression analysis was performed to identify reliable factors for diagnosing EPLs. A statistical significance threshold of 0.05 was established. The prevalence of EPLs involving pulpal and periodontal tissues was 29.49%. Type 1 lesions (EPLs involving only pulpal tissue) were most commonly seen at 41-45 years of age, type 2 lesions (EPLs involving primary pulpal and secondary periodontal tissue), and type 3 lesions (EPLs involving only periodontal tissue) at 26-30 years of age, and type 4 lesions (EPLs involving primary periodontal and secondary pulpal tissue) at 31-35 years of age. The pulp was found to be non-vital in all cases of type 3 lesions, and faulty restoration or improper root canal treatment (RCT) was the main risk factor for such lesions. Occupational trauma was found to be the most common risk factor for type 3 and type 4 lesions. Smoking, age, tooth type, occlusal trauma, faulty restorations and RCT, presence of caries, periapical pathology, periodontitis, bone loss, and pulp vitality were significantly associated with EPLs. Pulp vitality and bone loss were two prognostic predictors of EPLs.