Search

Angiogenesis is the determining factor during dental pulp regeneration. Six-twelve leukemia (STL) is identified as a key regulatory factor on the biological function of dental pulp stem cells (DPSCs) under hypoxic conditions, but its effect on angiogenesis is unclear. Co-culture of DPSCs and human umbilical vein endothelial cells (HUVECs) is used to detect tubule formation ability in vitro and the angiogenesis ability in vivo. RNA-seq and bioinformatic analyses are performed to screen differentially expressed genes. Seahorse Cell Mito Stress Test is proceeded to exam mitochondrial respiration. STL decreased tubule formation and mitochondrial respiration of DPSCs in vitro and restrained the number of blood vessels and the expression of VEGF in new formed tissue in vivo. Furthermore, pretreating STL-depleted DPSCs with rotenone, a mitochondrial respiration inhibitor, counteracted the promoting effect of STL knockdown on tubule formation. Then, RNA-seq and bioinformatic analyses identified some angiogenesis relevant genes and pathways in STL-depleted DPSCs. And STL enhanced expression of mRNA-ring finger protein 217 (RNF217), which inhibited the tubule formation and mitochondrial respiration of DPSCs. STL inhibited the angiogenesis of DPSCs through depressing mitochondrial respiration by enhancing RNF217, indicating that STL is a potential target for angiogenesis of DPSCs., (© 2024 The Author(s). Advanced Biology published by Wiley‐VCH GmbH.)

Introduction: Determining the health the status of the pulp is crucial in treatment planning. Both sensibility and vitality testing techniques may be employed. Sensibility testing may be inaccurate in teeth with incomplete root apices. This study intends to compare the accuracy of cold testing (CT), electric pulp testing (EPT) and pulse oximetry (PO) in determining pulpal status of mature and immature anterior teeth., Methods: 20 mature and 20 immature maxillary permanent incisors of healthy 6-12-year-olds were included. Teeth were categorised as mature permanent central incisors, immature permanent central incisors, and a negative control group with endodontically treated incisors. Vitality and sensitivity tests were performed using EPT, CT, and PO, with measurements taken thrice per tooth. PO was measured with infant pulse oximetry probe sensors placed on the tooth surfaces and fingers. Descriptive statistics were computed, and data distribution was assessed using the Shapiro-Wilk test. The Spearman correlation coefficient analysed correlations between dental and finger SpO 2 measurements, while the Kruskal-Wallis test with Dunn post-hoc analysis compared SpO2 and EPT measurements across tooth development stages, with a significance threshold set at p < 0.05., Results: SpO 2 values were significantly higher in immature teeth compared to mature teeth (p < 0.05), and both were significantly higher than in the negative control group. There was no significant correlation between SpO 2 values measured from fingers and teeth. EPT values were significantly higher in immature teeth compared to mature teeth (p < 0.001). The accuracy rate of PO, EPT, and cold tests was 100% in this study, with no false positive or negative responses in the control group. The SpO 2 values in mature and immature vital teeth ranged between 80-92%., Conclusions: PO is a reliable and non-invasive method for determining pulp vitality in both mature and immature teeth, comparable to traditional sensitivity tests like EPT and CT. PO can be considered an alternative vitality test, especially useful in paediatric dental patients due to its atraumatic and objective nature. Further studies with larger sample sizes and additional vitality tests like doppler flowmetry are recommended to enhance the clinical diagnosis of pulp vitality in anterior and posterior teeth., (© 2024. The Author(s), under exclusive licence to British Dental Association.)

Successful dental pulp regeneration is closely associated with rapid revascularization and angiogenesis, processes driven by the Jagged1(JAG1)/Notch signaling pathway. However, soluble Notch ligands have proven ineffective in activating this pathway. To overcome this limitation, a Notch signaling hydrogel is developed by indirectly immobilizing JAG1, aimed at precisely directing the regeneration of vascularized pulp tissue. This hydrogel displays favorable mechanical properties and biocompatibility. Cultivating dental pulp stem cells (DPSCs) and endothelial cells (ECs) on this hydrogel significantly upregulate Notch target genes and key proangiogenic markers expression. Three-dimensional (3D) culture assays demonstrate Notch signaling hydrogels improve effectiveness by facilitating encapsulated cell differentiation, enhancing their paracrine functions, and promoting capillary lumen formation. Furthermore, it effectively communicates with the Wnt signaling pathway, creating an odontoinductive microenvironment for pulp-dentin complex formation. In vivo studies show that short-term transplantation of the Notch signaling hydrogel accelerates angiogenesis, stabilizes capillary-like structures, and improves cell survival. Long-term transplantation further confirms its capability to promote the formation of pulp-like tissues rich in blood vessels and peripheral nerve-like structures. In conclusion, this study introduces a feasible and effective hydrogel tailored to specifically regulate the JAG1/Notch signaling pathway, showing potential in advancing regenerative strategies for dental pulp tissue., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Objectives: During caries progression, dental pulp is increasingly pathologically affected. Since the accurate assessment of pulp is of vital importance in clinical decision-making, this study aimed to evaluate pulpal condition in the early stages of caries via laser Doppler (LD) flowmetry and histologic analysis and determine their agreement., Methods: Fourteen patients with severe dental crowding were included. Prior to extractions and orthodontic treatment, dental pulp condition of 52 premolars was evaluated via LD flowmetry. Teeth were assessed for the presence of caries and lesions were graded according to the International Caries Detection and Assessment System (ICDAS). After extractions, teeth were split and histologically stained for endothelial cells with anti-von Willebrand factor and Movat pentachrome for collagen. Volume densities of vessels (V vasc ) and collagen were calculated., Results: There was a significant negative correlation between LD flow and V vasc of the dental pulp with ICDAS grade. Pulpal LD flow and V vasc in teeth with the initial lesion were increased, decreasing with progressing stages of caries. A significant positive correlation between the the pulpal LD flow and V vasc , and a negative correlation of LD flow with collagen fibre density were noted., Conclusions: Caries affects the physiology of the dental pulp, initially with increasing vascularity, and decreasing vascularity at later stges of caries progression. Collagen contents increase with grades of ICDAS. LD flow shows good agreement with the histologic constitution of the dental pulp. Use of clinical measurements of pulpal LD flow could provide a good noninvasive indication of pulpal vascular state and its health., Competing Interests: Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Aim: Angiogenesis is a key event in the successful healing of pulp injuries, and hypoxia is the main stimulator of pulpal angiogenesis. In this study, we investigated the effect of hypoxia on the proangiogenic potential of human dental pulp stem cells (hDPSCs) and the role of miR-143-5p in the process., Methodology: Human dental pulp stem cells were isolated, cultured and characterized in vitro. Cobalt chloride (CoCl 2 ) was used to induce hypoxia in hDPSCs. CCK-8 and Transwell assays were used to determine the effect of hypoxia on hDPSCs proliferation and migration. Quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting (WB) and ELISA were performed to assess the mRNA and protein levels of HIF-1α and angiogenic cytokines in hDPSCs. The effect of hypoxia on hDPSCs proangiogenic potential was measured in vitro using Matrigel tube formation and chick chorioallantoic membrane (CAM) assays. Recombinant lentiviral vectors were constructed to stably overexpress or inhibit miR-143-5p in hDPSCs, and the proangiogenic effects were assessed using qRT-PCR, WB, and tube formation assays. miR-143-5p target genes were identified and verified using bioinformatics prediction tools, dual-luciferase reporter assays and RNA pull-down experiments. Finally, a subcutaneous transplantation model in nude mice was used to determine the effects of hypoxia treatment and miR-143-5p overexpression/inhibition in hDPSCs in dental pulp regeneration., Results: Hypoxia promotes hDPSCs proliferation, migration and proangiogenic potential. The in vivo experiments showed that hypoxia treatment (50 and 100 μM CoCl 2 ) promoted pulp angiogenesis and dentine formation. In contrast to the levels of proangiogenic factors, miR-143-5p levels decreased with increasing CoCl 2 concentration. miR-143-5p inhibition significantly promoted proangiogenic potential of hDPSCs, whereas miR-143-5p overexpression inhibited angiogenesis in vitro. Dual-luciferase reporter assay identified retinoic acid receptor-related orphan receptor alpha (RORA) as an miR-143-5p target gene in hDPSCs. RNA pull-down experiments demonstrated that HIF-1α and RORA were pulled down by biotin-labelled miR-143-5p, and the levels of HIF-1α and RORA bound to miR-143-5p in the hypoxia group were lower than those in the normoxia group. Inhibition of miR-143-5p expression in hDPSCs promoted ectopic dental pulp tissue regeneration., Conclusions: CoCl 2 -induced hypoxia promotes hDPSCs-driven paracrine angiogenesis and pulp regeneration. The inhibition of miR-143-5p upregulates the proangiogenic potential of hDPSCs under hypoxic conditions by directly targeting HIF-1α and RORA., (© 2024 British Endodontic Society. Published by John Wiley & Sons Ltd.)

Introduction: Diagnostic procedures for pulp vitality assessment are a crucial aspect of routine dental practice. This review aims to provide a comprehensive overview of nontraditional techniques and methodologies for assessing pulp vitality, specifically exploring promising approaches that are currently not used in dental practice., Methods: The study protocol was registered a priori (https://osf.io/3m97z/). An extensive electronic search was conducted across multiple databases, including MEDLINE via PubMed, Scopus, Web of Science, and Embase. Inclusion criteria were guided by the research question based on the PCC model as follows: "What are the potential nontraditional techniques (Concept) for assessing pulp vitality (Population) in the field of endodontics or clinical practice (Context)?" Studies were included that explored possible approaches to pulp vitality assessment, utilizing a range of techniques, whilst any studies using traditional pulp tests (cold, heat, and electric stimulation) or well-known methods (pulse oximetry and laser Doppler flowmetry) were excluded. Reviewers independently screened articles and extracted data. A patent search was also performed., Results: Of 3062 studies, 65 were included that described nontraditional approaches for assessing pulp vitality. These included a range of optical diagnostic methods, ultrasound Doppler flowmetry (UDF), magnetic resonance imaging (MRI), terahertz imaging, tooth temperature measurements, as well as invasive methodologies, including 133 xenon washout, radioisotope-labelled tracers, hydrogen gas desaturation, intravital microscopy and fluorescent microspheres isotope clearance. The patent search included artificial intelligence and biomarkers methods., Conclusions: This review provides details for potential innovative tests that may directly describe pulp vitality. Importantly, these methods range from clinically impractical through to promising methods that may transform clinical practice. Several nontraditional techniques have the potential to enhance diagnostic accuracy and could provide valuable insights into the assessment of pulp vitality in challenging clinical scenarios., (© 2024 The Authors. International Endodontic Journal published by John Wiley & Sons Ltd on behalf of British Endodontic Society.)

Introduction: Heparan sulfate (HS) is a major component of dental pulp tissue. We previously reported that inhibiting HS biosynthesis impedes endothelial differentiation of dental pulp stem cells (DPSCs). However, the underlying mechanisms by which exogenous HS induces DPSC differentiation and pulp tissue regeneration remain unknown. This study explores the impact of exogenous HS on vasculogenesis and dentinogenesis of DPSCs both in vitro and in vivo., Methods: Human-derived DPSCs were cultured in endothelial and odontogenic differentiation media and treated with HS. Endothelial differentiation of DPSCs was investigated by real-time polymerase chain reaction and capillary sprouting assay. Odontogenic differentiation was assessed through real-time polymerase chain reaction and detection of mineralized dentin-like deposition. Additionally, the influence of HS on pulp tissue was assessed with a direct pulp capping model, in which HS was delivered to exposed pulp tissue in rats. Gelatin sponges were loaded with either phosphate-buffered saline or 10 1 -10 2  μg/mL HS and placed onto the pulp tissue. Following a 28-day period, tissues were investigated by histological analysis and micro-computed tomography imaging., Results: HS treatment markedly increased expression levels of key endothelial and odontogenic genes, enhanced the formation of capillary-like structures, and promoted the deposition of mineralized matrices. Treatment of exposed pulp tissue with HS in the in vivo pulp capping study induced formation of capillaries and reparative dentin., Conclusions: Exogenous HS effectively promoted vasculogenesis and dentinogenesis of DPSCs in vitro and induced reparative dentin formation in vivo, highlighting its therapeutic potential for pulp capping treatment., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: The evaluation of pulp status is crucial for avulsed immature permanent teeth after replantation. In addition to commonly used clinical and radiographic examinations providing clinical evidence, the oxygen saturation test may offer valuable assistance. The aim of this study was to analyze the efficacy of a pulse oximeter in evaluating pulp status in avulsed and replanted immature permanent teeth., Methods: A prospective observational study was performed including 51 avulsed and replanted immature permanent teeth. Routine clinical and radiographic examinations were performed and used as the basis for the diagnosis of pulp status during the 1-year follow-up period. Meanwhile, the oxygen saturation values of these teeth were recorded using a modified pulse oximeter at each visit., Results: Seven teeth completed pulp revascularization (success group), whereas 44 teeth failed to revascularize (failure group). Abnormal clinical and/or radiographic manifestations in the failure group were observed at an average period of 42.7 days, which was too late because a high incidence of inflammatory root resorption (43.18%) had occurred. For oxygen saturation tests, teeth in the success group showed an immediate postreplantation oxygen value of 70.71 ± 3.35, then an upward trend starting from the 2-week postreplantation visit, and a significantly increased final value of 81.86 ± 2.34 at the 1-year visit. In contrast, no increase trend was found for teeth in the failure group because abnormal clinical and/or radiographic manifestations emerged., Conclusions: The oxygen saturation test is a reliable diagnostic method to evaluate pulp status of avulsed teeth as early as 2 weeks after replantation., (Copyright © 2024 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: Orthognathic surgery has the potential to compromise the vitality of the teeth. This paper aims to assess changes in pulp blood flow (PBF) and pulp sensibility (PS) of the anterior dentition following orthognathic surgery and to assess the influence of the proximity of the surgical osteotomy on the PBF and/or PS., Methods: Twenty-six patients undergoing orthognathic surgery (Le Fort I or bilateral sagittal split osteotomy [BSSO]) were compared to sixteen control patients treated by fixed appliances only using Laser Doppler flowmeter (LDF) and thermal testing (CO2 snow). Surgery patients were tested at T1 (presurgery), T2 (4-5 weeks postsurgery), T3 (3 months postsurgery), and T4 (6 months postsurgery). Control patients were tested at T1 (pretreatment), T2 (6 months posttreatment), T3 (12 months posttreatment), and T4 (18 months posttreatment). Differences between the maxilla and mandible were assessed., Results: No differences in PBF or PS were recorded in the control group. In the surgery group, both jaws followed the same pattern after surgery, an initial decrease at T2 followed by a gradual recovery to pretreatment PBF levels with no significant difference between T1 versus T4 in both jaws. No difference in PBF was observed between the maxilla and mandible at any testing time interval., Conclusions and Clinical Implications: PBF and PS of the anterior dentition was severely affected immediately postsurgery, followed by a gradual increase to full recovery. This pattern of recovery was exhibited in both jaws. A negative sensibility response or discoloration should not be seen as an indication of irreversible ischemic pulp changes. Monitoring for at least 6 months or using LDF as a confirmatory test is required before any irreversible endodontic treatment is to be considered., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

The process of neovascularization during cell-based pulp regeneration is difficult to study. Here we developed a tube model that simulates root canal space and allows direct visualization of the vascularization process in vitro. Endothelial-like cells (ECs) derived from guiding human dental pulp stem cells (DPSCs) into expressing endothelial cell markers CD144, vWF, VEGFR1, and VEGFR2 were used. Human microvascular endothelial cells (hMVECs) were used as a positive control. DPSC-ECs formed tubules on Matrigel similar to hMVECs. Cells were mixed in fibrinogen/thrombin or mouse blood and seeded into wells of 96-well plates or injected into a tapered plastic tube (14 mm in length and 1 or 2 mm diameter of the apex opening) with the larger end sealed with MTA to simulate root canal space. Cells/gels in wells or tubes were incubated for various times in vitro and observed under the microscope for morphological changes. Samples were then fixed and processed for histological analysis to determine vessel formation. Vessel-like networks were observed in culture from 1 to 3 d after cell seeding. Cells/gels in 96-well plates were maintained up to 25 d. Histologically, both hMVECs and DPSC-ECs in 96-well plates or tubes showed intracellular vacuole formation. Some cells showed merged large vacuoles indicating the lumenization. Tubular structures were also observed resembling blood vessels. Cells appeared healthy throughout the tube except some samples (1 mm apical diameter) in the coronal third. Histological analysis also showed pulp-like soft tissue throughout the tube samples with vascular-like structures. hMVECs formed larger vascular lumen size than DPSC-ECs while the latter tended to have more lumen and tubular structure counts. We conclude that DPSC-ECs can form vascular structures and sustained in the 3-dimensional fibrin gel system in vitro. The tube model appears to be a proper and simple system simulating the root canal space for vascular formation and pulp regeneration studies., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: One of the most important steps in deciding on the treatment of a tooth is to determine the vitality and health status of the pulp. Since immature teeth innervation is not completed, the response to sensitivity tests may not yield definite results. Pulse oximetry (PO) which is considered as a vitality test, measures the arterial oxygen saturation (SpO 2 ). This study aims to compare PO, electric pulp test (EPT) and cold test in mature and immature permanent teeth., Methods: 20 immature and 20 mature permanent incisors of 6-12-year-old ASA1 children who did not use any analgesics, were included in the study. Pulp vitality of the teeth was determined by EPT, cold test and PO. An infant probe of PO device (CMS60D, Contec Medical Systems Co. Ltd, China) was used to determine the SpO 2 of the teeth. The SpO 2 level is controlled on the patient's finger by a children's probe and an infant probe of PO. Shapiro-Wilk, Spearman rank correlation test and Kruskal-Wallis test/Dunn post-hoc analysis were used for statistical comparisons., Results: There was no significant correlation between finger SpO 2 and the mature/immature teeth SpO 2 (r=-0.026, r = 0.253). Arterial oxygen saturation values in the immature teeth were significantly higher than in the mature teeth (p = 0.002). There was a high correlation between the vitality response of the EPT, cold test and PO., Conclusions: Pulse oximetry can be used as an effective vitality test compared to sensitivity tests in both immature and mature permanent incisors., (© 2024. The Author(s).)

To explore a new method to implant deciduous tooth pulp into the canal of young permanent teeth with necrotic pulps and apical periodontitis for the regenerative endodontic treatment of tooth no: 41 in a 7-year-old male. Briefly, 1.5% Sodium Hypochlorite (NaOCl) irrigation and calcium hydroxide-iodoform paste were used as root canal disinfectant at the first visit. After 2 weeks, the intracanal medication was removed, and the root canal was slowly rinsed with 17% Ethylene Diamine Tetraacetic Acid (EDTA), followed by flushing with 20 mL saline and then drying with paper points. Tooth no: 72 was extracted, and its pulp was extracted and subsequently implanted into the disinfected root canal along with induced apical bleeding. Calcium hydroxide iodoform paste was gently placed over the bleeding clot, and after forming a mineral trioxide aggregate (MTA) coronal barrier, the accessed cavities were restored using Z350 resin composite. The root developments were evaluated via radiographic imaging at 6 months, 1 year and 5 years after treatment. Imaging and clinical analysis showed closure of the apical foramen, thickening of the root canal wall, and satisfactory root length growth. Autologous transplantation might be useful to regenerate dental pulp in necrotic young permanent teeth., Competing Interests: The authors declare no conflict of interest., (©2024 The Author(s). Published by MRE Press.)

Purpose: To explore the efficacy of iRoot BP plus in the treatment of adult carious pulp exposure and its impact on pulp blood flow., Methods: A total of 126 cases of 156 permanent teeth from adult patients with carious pulp exposure who were treated from January 2020 to January 2022 were selected, the patients were divided into experimental group(63 cases with 79 permanent teeth) and control group(63 cases with 77 permanent teeth) by the envelope method. The experimental group was treated with iRoot BP plus, while the control group was treated with mineral trioxide polymer. The differences in treatment effectiveness, operation time, and tooth discoloration between the two groups were observed. Statistical analysis was performed with SPSS 22.0 software package., Results: There was no significant difference in treatment success rates between the experimental group and the control group at 3, 6, and 12 months after surgery(P＞0.05). The operating time for each capsule in the experimental group was (2.53±0.41) min, which was significantly shorter than that in the control group(P＜0.05). The incidence of tooth discoloration in the experimental group at 12 months after surgery was 3.80%, which was significantly lower than that in the control group (P＜0.05). The bite force quotient and masticatory efficiency of the experimental group 12 months after operation were (16.65±1.14) Ibs and (94.45±5.65)%, which were significantly higher than those of the control group(P＜0.05)., Conclusions: IRoot BP plus has good efficacy in the treatment of adult carious pulp exposure, with advantages such as convenient operation, less tooth discoloration, less inflammatory reactions and stable pulp blood flow after decline.

The Aim of the Study: To assess the effectiveness of pulp revascularization procedure in children with external inflammatory root resorption (EIRR) after constant teeth injury., Materials and Methos: The study comprised 17 children aged 6-10 years diagnosed with EIRR as a long-term complication of dental trauma in 19 teeth. EIRR was diagnosed with periapical radiographs and CBCT was performed to further assess the pathology extension. Pulp revascularization was carried out in all 19 teeth., Results: There was no resorption progression in all cases. EIRR areas were substituted by bone. In 10 from 19 teeth with early stages of root development bone or cement-like tissue ingrowth into the root canal was observed radiologically. In cases of severe EIRR this ingrowth may partially compensate for lost tissues which is confirmed by a high percentage (94.7%) of functional teeth during mean follow up time of 38±10 months., Conclusion: Pulp revascularization is an effective method for retaining teeth with EIRR for a relatively long period of time and allows maintaining alveolar bone volume both due to functional tooth preservation and healing of bone lesions in periapical and resorption areas.

The dental pulp is a highly vascularized and innervated loose connective tissue surrounded by hard dental tissues - enamel and dentine. With the primary dentin formation and the closure of the root apex, the conditions in the dental pulp change and pulp tissue compliance are reduced. Endothelial cells of pulpal blood vessels are highly differentiated and are capable of adaptation to changes in the environment. We aimed to evaluate the phenotypic plasticity of endothelial cells of pulpal blood vessels in permanent premolars with open (N = 6) or closed root apex (N = 30). The pulp tissue was stained with hematoxylin-eosin (HE) for the histological analysis, and immunohistochemically for a cluster of differentiation 31 (CD31), a cluster of differentiation 34 (CD34), and for smooth muscle actin (SMA) to detect vessels with CD31, CD34, and SMA positive endothelial cells. We used the student's t-test and Pearson correlation test for the statistical analysis. We found a significantly higher percentage of the vessels with CD31 (P = 0.005) and CD34 (P = 0.000) positive endothelial cells in the group of teeth with closed root apex compared to the group with open apex. A significant positive correlation between SMA positive and CD31 positive vessels (P = 0.003) and between CD31 positive and CD34 positive vessels (P = 0.031) was also found. We conclude that the endothelial cells of dental pulp vessels express a small amount of CD31, but have a pronounced expression of SMA and CD34, which indicates their progenitor potential and contractile ability.

The aim of this study is to provide criteria for the choice of the surgical approach for extraction of high inverted mesiodens. The operation statistics, life quality of postoperative patients, and the operative injury/recovery were compared and analysed. The laser Doppler blood flowmetry, laser speckle contrast imaging, and electric pulp testing were explored to detect the postoperative pulp and gingiva blood supply of adjacent teeth. For the clinician's primary concerns, the surgical time, the volume of osteotomy, and the amount of bleeding in the labial approach group (The p values are 0.0001, <0.0001, and 0.0131, respectively.) and intranasal approach group (All p values were <0.0001.) were significantly less than that in the palatal approach group. However, from the patient's perspective, the postoperative swelling in the labial approach was far more than that in the intranasal approach group (p =0.0044), with unsurprisingly lower satisfaction (p <0.0001). There were no significant differences in pulp and gingival blood supply of adjacent teeth and jaw development. Trauma was manageable in all patients. Within the limitations of the study it seems that extraction of mesiodens by the intranasal approach achieves a delicate balance between reducing surgical trauma and optimizing postoperative recovery., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: A laser doppler flowmetry (LDF) test can reflect the pulp vitality caused by the change in pulp blood flow (PBF). This study aimed to investigate the PBF of the permanent maxillary incisors using LDF and to calculate the clinical reference range and coincidence rate for pulp vitality using PBF as an indicator., Methods: School-age children (7-12 years) were recruited randomly. A total of 455 children (216 female and 239 male) were included in this study. An additional 395 children (7-12 years) who attended the department due to anterior tooth trauma from October 2015 to February 2018 were included to assess the clinical occurrence rate. The PBF was measured using LDF equipment and an LDF probe., Results: The clinical reference range of PBF values for the permanent maxillary incisors (teeth 11, 12, 21, and 22) in children were from 7 to 14 perfusion units (PU), 11 (6.016; 11.900 PU), 12 (6.677; 14.129 PU), 21 (6.043;11.899 PU), and 22 (6.668; 14.174 PU). There was a statistically significant correlation between PBF and children's age (p < 0.000) without any significant gender discrimination (p = 0.395). For all incisors, for any age group, the PBF detection value of the lateral incisors was significantly higher than that of the central incisors (p < 0.05). The clinical coincidence rate of detecting PBF in the traumatic teeth was 90.42% and the sensitivity and specificity were 36.99% and 99.88%, respectively., Conclusions: The determination of the PBF clinical reference range and clinical coincidence rate for the permanent maxillary incisors in children using LDF provided a promising theoretical basis for clinical applications., (© 2023. The Author(s).)

Data Sources: Electronic databases PubMed, Scopus and Embase were systematically searched and restricted to articles published between February 2009 and 2022., Study Selection: Studies were categorized using the modified method by the Swedish Council of Technology Assessment in Health Care. 20 studies were included, one of which was categorized as high quality (Grade A) and 19 of which were of moderate quality (Grade B). Exclusion criteria included articles with insufficient descriptions of reliability and reproducibility testing, review articles and case reports, and studies including traumatised teeth., Data Extraction and Synthesis: Three independent authors examined titles, abstracts and full texts of relevant articles against the inclusion criteria. Disagreements were resolved by discussion. Retrieved studies were assessed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data extracted included tooth movement performed, the appliance and force used, follow-up of subjects, changes in pulpal blood flow (PBF), tooth sensibility, expression of inflammation-related proteins, along with pulpal histology and morphology changes during tooth movement (intrusion, extrusion and tipping). Overall risk of bias was unclear., Results: A reduction in pulpal blood flow and tooth sensibility due to the application of orthodontic forces was reported by studies included in the review. Increases in the activity of proteins and enzymes related to inflammation of the pulp was reported. Two studies reported histological changes of the pulpal tissues related to orthodontic treatment., Conclusions: Orthodontic forces cause multiple temporary detectable changes in the dental pulp. The authors conclude there are no clear signs of permanent pulpal damage to healthy teeth due to the application of orthodontic forces., (© 2023. The Author(s), under exclusive licence to British Dental Association.)

Objective: This study aims to determine and compare the dental pulp and gingival blood flow in patients referred for oropharyngeal radiotherapy (RT) at three different time points: before the start, immediately after, and six months following the completion of RT. The aim is also to evaluate the dependence of the pulp and gingival blood flow on the radiation dose., Methodology: A prospective study included 10 patients referred for intensity-modulated RT (IMRT) in the oropharyngeal region, with at least one intact tooth surrounded by a healthy gingiva. The dose received by each selected tooth and adjacent gingiva was determined according to the map of treatment planning and computer systems. The blood flow measurements were performed using the laser Doppler flowmetry (LDF) method., Results: Comparing vascular flows at three different time points, the median blood flow in the dental pulp showed no statistically significant difference (p=0.325), contrary to gingiva (p=0.011). Immediately after RT completion, the gingival flow significantly increased compared to its starting point (p=0.012). The pulp flow correlated negatively with the radiation dose, whereas a strong correlation was noted 6 months following the RT completion., Conclusions: RT caused a significant acute gingival blood flow increase, followed by a long-term (over six months) tendency to return to the starting levels. The dental pulp blood flow is differently affected by higher radiation doses (over 50Gy) in comparison to lower doses (below 50Gy). During RT planning, considering the possibility of protecting the teeth localized near the Gross Tumor Volume as a sensitive organ is recommended.

Background: Previous studies of pulpal blood flow (PBF) changes in anterior teeth have been limited in the early phase of orthodontic treatment; less is known about the blood supply of anterior teeth in bimaxillary protrusion patients after orthodontic retraction., Methods: Fifty bimaxillary protrusion patients (25 orthodontic patients ready for debonding and 25 non-orthodontic patients) were selected as study participants. The PBF of maxillary and mandibular anterior teeth were measured using laser Doppler flowmetry. For orthodontic patients, the PBF was measured at 1 day (T1), 1 month (T2), and 3 months (T3) after fixed appliance removal. Non-orthodontic patient PBF was measured as a control. Cone-beam computed tomography (CBCT) examinations before and after orthodontic treatment were performed for orthodontic patients to measure the root resorption. The anterior teeth in orthodontic group were further divided into subgroups according to root resorption and patient age., Results: At T1 and T3, PBF changes did not differ significantly between the orthodontic and non-orthodontic groups. Maxillary lateral incisor, maxillary central incisor, and mandibular lateral incisor PBFs at T2 were significantly higher in the orthodontic group (P = 0.048, P = 0.04, and P = 0.021). No significant difference in PBF was found between the root resorption and non-resorption subgroups at any time point. Adolescent patients showed a higher PBF in the maxillary lateral incisor at T2 (12.23 ± 3.48) relative to that at T1 (9.10 ± 3.76) and T3 (9.81 ± 2.80) with statistically significant difference (P = 0.020)., Conclusion: For bimaxillary protrusion patients with four premolars extraction, PBF in the maxillary anterior teeth increased transiently after orthodontic appliance removal and then returned to non-orthodontic levels 3 months later. This effect was more pronounced in adolescents. The PBF of anterior teeth after orthodontic retraction may not be influenced by root resorption., (© 2022. The Author(s).)

Introduction: Orthodontic force triggers a sequence of biological responses that can affect dental pulp. The aim of this study was to systematically evaluate the clinical and radiographic findings of orthodontic force application on dental pulp., Methods: Two reviewers comprehensively and systematically searched 6 electronic databases (Latin American and Caribbean Health Sciences [LILACS], Embase, Cochrane Library, MEDLINE/PubMed, Scopus, and Web of Science) and the gray literature (Google Scholar, OpenGrey, and ProQuest) until April 2021. According to the PICOS criteria, randomized clinical trials and observational studies that evaluated clinical or radiographic findings compatible with dental pulp changes due to orthodontic force were included. Studies in open apex or traumatized teeth, case series or reports, and laboratory-based or animal studies were excluded. The Newcastle-Ottawa Scale and Cochrane Risk of Bias 2.0 tool were used to determine the risk of bias assessment. The overall certainty level was evaluated with the Grading of Recommendations, Assessment, Development and Evaluations tool., Results: Twenty-six studies were included. Among the clinical findings, orthodontic force promoted an increased pulp sensibility response and decreased pulp blood flow. Changes in pulp cavity volume and increased incidence of pulp stones were the radiographic findings observed. The studies presented a moderate risk of bias for most of the domains. The certainty of the evidence was considered very low., Conclusions: Orthodontic force promoted changes in the dental pulp, generating clinical and radiographic findings. It is crucial to know these changes so that orthodontic mechanics can be safely performed. The clinician has effective noninvasive methods to assess the health and possible pulp changes during orthodontic treatment., (Copyright © 2021 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Since the discovery of dental pulp stem cells, a lot of teams have expressed an interest in dental pulp regeneration. Many approaches, experimental models and biological explorations have been developed, each including the use of stem cells and scaffolds with the final goal being clinical application in humans. In this review, the authors' objective was to compare the experimental models and strategies used for the development of biomaterials for tissue engineering of dental pulp with stem cells. Electronic queries were conducted on PubMed using the following terms: pulp regeneration, scaffold, stem cells, tissue engineering and biomaterial. The extracted data included the following information: the strategy envisaged, the type of stem cells, the experimental models, the exploration or analysis methods, the cytotoxicity or viability or proliferation cellular tests, the tests of scaffold antibacterial properties and take into account the vascularization of the regenerated dental pulp. From the 71 selected articles, 59% focused on the "cell-transplantation" strategy, 82% used in vitro experimentation, 58% in vivo animal models and only one described an in vivo in situ human clinical study. 87% used dental pulp stem cells. A majority of the studies reported histology (75%) and immunohistochemistry explorations (66%). 73% mentioned the use of cytotoxicity, proliferation or viability tests. 48% took vascularization into account but only 6% studied the antibacterial properties of the scaffolds. This article gives an overview of the methods used to regenerate dental pulp from stem cells and should help researchers create the best development strategies for research in this field.

Objectives: The present study aimed firstly, to investigate whether pulpal circulatory changes elicited by innocuous tooth cooling and foot heating can be monitored with transmitted-light plethysmography (TLP), which detects pulpal blood volume changes, and secondly, to assess the effect of autonomic nervous control on TLP values., Design: Thirty sound permanent maxillary incisors in 30 healthy volunteers (age: 25-35 years) were examined. The photodiode and 525-nm light-emitting diode of a prototype TLP system (J. Morita) were fixed onto the palatal and labial side, respectively, of each tooth with a custom-made acrylic cap. The subjects were stimulated for 10 min by cold (0 °C) water application to the experimental tooth or 30 min by foot heating with a footbath (43 °C). TLP and finger plethysmography were simultaneously recorded before (baseline), during and after stimulation. TLP values and autonomic nerve activity were statistically analyzed using a repeated measures one-way ANOVA followed by Tukey post-hoc test and partial correlation analysis., Results: TLP values decreased significantly after both innocuous stimuli (P < 0.05), and returned to their baseline levels shortly after the removal of the stimuli. There was no significant serial correlation between the autonomic nervous activity and TLP values (P > 0.05)., Conclusion: TLP was able to monitor the pulpal circulatory changes evoked by innocuous stimuli. Systemic autonomic nervous control mechanisms were not associated with the pulpal circulatory changes, suggesting the involvement of other mechanisms, such as somatosensory-sympathetic nervous control., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose/Aim : The aim of this study was to explore whether dentinogenesis imperfecta (DGI)-related aberrations are detectable in odontogenic tissues. Materials and Methods : Morphological and histological analyses were carried out on 3 teeth (two maxillary 1 st molars, one maxillary central incisor) extracted from a patient with DGI Type II. A maxillary 2 nd molar teeth extracted from a healthy patient was used as control. A micro-computed tomographic (μCT) data-acquisition system was used to scan and reconstruct samples. Pentachrome and picrosirius red histologic stains were used to analyze odontogenic tissues and their collagenous matrices. Results : Our findings corroborate DGI effects on molar and incisor root elongation, and the hypo-mineralized state of DGI dentin. In addition to these findings, we discovered changes to the DGI pulp cavity: Reactionary dentin formation, which we theorize is exacerbated by the early loss of enamel, nearly obliterated an acellular but still-vascularized DGI pulp cavity. We also discovered an accumulation of lamellated cellular cementum at the root apices, which we hypothesize compensates for the severe and rapid attrition of the DGI tooth. Conclusions : Based on imaging and histological data, we propose a novel hypothesis to explain the complex dental phenotypes observed in patients with DGI Type II.

Objective: Pulp revascularization is an effective treatment for immature necrotic teeth. Calcium hydroxide has been used in pulp revascularization as an intracanal medication due to its antimicrobial action and the non-exhibition of crown discoloration and cytotoxicity for stem cells from the apical papilla. Our study aimed to investigate the clinical success and quantitative radiographic changes of root development in immature traumatized teeth using calcium hydroxide plus 2% chlorhexidine gel as intracanal medication., Methodology: In this retrospective study, 16 patients were treated with a standardized pulp revascularization protocol. Calcium hydroxide and 2% chlorhexidine gel were manipulated in a 1:1 (v/v) ratio and inserted into root canals with Lentulo spirals (Dentsply Maillefer, Baillaigues, Switzerland). Patients were followed up for a period from 9 to 36 months for the evaluation of clinical and radiological data. Radiographic measurements of root length, root width, apical diameter, and MTA placement from the apex were quantified using software ImageJ. Wilcoxon test and t-test were used, according to nonparametric or parametric data, respectively, for changes over time in root length, root width, and apical diameter., Results: Fifteen teeth survived during the follow-up period (93.75%) and met the criteria for clinical success. Although the changes seem to be very small in many cases, significant increases in the average root length (14.28%, p<0.0001), root width (8.12%, p=0.0196), and decrease in apical diameter (48.37%, p=0.0007) were observed. MTA placement from the apex and age at the time of treatment was not significantly associated with the quantitative radiographic outcomes., Conclusions: Pulp revascularization in traumatized immature teeth treated with calcium hydroxide plus 2% chlorhexidine gel as intracanal medication had high success and survival rates, showing periodontal healing and resolution of signs and symptoms. However, concerning the continued root development, the outcomes can still be considered unpredictable.

Dental pulp, plays an indispensable role in maintaining homeostasis of the tooth. Pulp necrosis always causes tooth nutrition deficiency and abnormal root development, which leads to tooth discoloration, fracture or even loss. Our previous study showed implantation of autologous SHED could regenerate functional dental pulp. However, the detailed mechanism of the implanted SHED participating in dental pulp regeneration remains unknown. In this study, we implanted SHED in a porcine dental pulp regeneration model to evaluate the regenerative effect and identify whether SHED promoted angiogenesis in regenerated dental pulp. Firstly we verified that xenogenous SHED had the ability to regenerated pulp tissue of host in vivo. Then we found the vasculature in regenerated pulp originated from implanted SHED. In addition, stem cells were isolated from regenerated dental pulp, which exhibited good multi-differentiation properties and promoted angiogenesis in pulp regeneration process and these results demonstrated that SHED promoted angiogenesis in stem cell-mediated dental pulp regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Several techniques have been introduced to improve the pulp revascularization outcomes. The use of the tissue graft can create more practical tissue regeneration, provide vascular supply, and enhance tissue healing. The aim of the present study was to investigate the histologic and molecular outcomes of pulp revascularization with buccal fat autotransplantation. Fifty-six open apex roots from four dogs aged 4-6 months were randomly allocated to five groups of endodontic regeneration models: Group 1 (negative control, n = 4); Group 2 (control and without intervention, n = 4); Group 3 (blood clot, n = 16); Group 4 (buccal fat autotransplantation, n = 16); and Group 5 (blood clot plus buccal fat autotransplantation, n = 16). After 3 months, the extracted dog teeth were analyzed by histological and immunohistochemical techniques. Furthermore, real-time quantitative polymerase chain reactions were implemented to assess the gene expression profiles of dentin sialophosphoprotein (DSPP), dentin matrix protein (DMP), collagen I (COL1), and alkaline phosphatase (ALP) on regenerated tissue in the root canals. There were no significant differences in the severity of inflammation and necrosis between intervention groups. Immunohistochemical analysis showed significant differences among the study groups in expression level of extracellular glycoproteins such as fibronectin, laminin, and tenascin C. Group 5 showed an increase in the expression of DMP1 and COL1 genes. The expression of DSPP gene increased significantly in Group 4. The expression of ALP gene increased significantly in Group 3. Using this procedure may open new fields of research for regenerative endodontic procedure in which tissue autotransplant, particularly adipose tissue, may improve the outcomes of pulp revascularization., (© 2020 John Wiley & Sons, Ltd.)

Introduction: Age-related changes of dental pulp tissue and atherosclerosis of carotid arteries as its feeding arteries could influence the functionality of pulpal circulation. The objective of our study was to evaluate the effect of aging (physiological process) and carotid bifurcation atherosclerosis (pathologic process) on the pulpal microcirculatory system using multifractal analysis of the laser Doppler flowmetry signal., Methods: Three groups of 10 subjects were enrolled in the study: the young group (healthy subjects, 20-25 years), the middle-aged group (healthy subjects, 50-60 years), and the clinical group (subjects with carotid bifurcation atherosclerosis, 50-60 years). Pulpal blood flow (PBF) signals recorded by laser Doppler flowmetry were assessed by multifractal analysis that estimates Hölder exponents of the signal. PBF levels, the average mean values, and the range of Hölder exponents were obtained., Results: PBF levels were significantly higher in the young group compared with the middle-aged and clinical groups, and the difference between the middle-aged and clinical groups was not statistically significant. The range of the Hölder exponents was narrower in the middle-aged and clinical groups than in the young group and narrower in the clinical group than in the middle-aged group. The average mean value of Hölder exponents was significantly higher in the young group than in the middle-aged and clinical groups, whereas there was no significant difference between the middle-aged and clinical groups., Conclusions: Our study investigating the multifractality of the PBF signal showed that the aging process and carotid atherosclerosis could affect the complex structure of PBF oscillations and contribute to a better understanding of pulpal hemodynamics., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Aim of the study: Deep carious lesions may cause irreversible pulpitis and the current endodontic treatment typically removes the whole dental pulp tissue, which finally reduces lifespan of the teeth. Nowadays, the most frequent treatment is based on removing the infected tissue and filling the root canal with inert synthetic materials. Tissue engineering approaches are important alternatives to the current treatment, because they can potentially maintain the biological function of the tooth instead of sacrificing it. Materials and Methods: In this study, we propose a tissue engineering approach based on a hand-held in situ bioprinting strategy. Our approach enabled bioprinting of cell-loaded collagen-based bioinks with suitable rheological, structural and biological properties, which allowed for vasculogenesis in the root canal. Results: The rheological properties of the bioprintable bioink were measured by oscillatory amplitude sweep testing and were corroborated by macroscopic evaluation after in vitro culture, in which printed bioinks maintained their original form without contraction. Moreover, we showed evidence for successful vasculogenesis in bioprintable bioinks with comparable quality and quantity to control fibrin and collagen non-bioprintable hydrogels. Conclusions: We conclude that hand-held bioprinting holds potential for in situ treatment of dental diseases with successful evidence for vascular tube formation, as an asset for maintenance of the biological function of the tooth.

The objective of this study is to observe and analyze the efficacy of calcium hydroxide and chlorhexidine in pulp revascularization after trauma in young permanent teeth. A total of 120 patients who were treated in our hospital for pulp revascularization after trauma in young permanent teeth were enrolled as research objects in the study. The patients were treated with calcium hydroxide and chlorhexidine and the overall treatment efficiency was statistically observed. The improvement in various indicators before and after treatment was observed, including pain symptom score, gum swelling symptom score, tooth looseness score. The overall treatment efficiency was recorded. The results showed that there were 70 cases of significant effective treatment, 42 cases of effective treatment, and 8 cases of ineffective treatment, respectively, with overall treatment efficiency of 93.33%. Compared with the pain score, gum swelling score and teeth looseness score before treatment, these indicators showed a significant improvement after treatment, p<0.05. The application of calcium hydroxide and chlorhexidine during pulp revascularization after trauma in young permanent teeth can significantly improve the therapeutic effect and achieve higher therapeutic efficiency, demonstrating huge application value.

Background: This study evaluated the antibacterial efficiency and ability of propolis to promote regeneration of immature permanent non-vital dogs' teeth., Methods: Ninety six immature permanent premolars teeth in 6 mongrel dogs were divided randomly into: experimental teeth (N = 72) and control teeth (N = 24). Periapical pathosis was induced in all experimental and positive control teeth. Experimental teeth were classified according to the used intra-canal medication into: group I (N = 36), propolis paste was used and group II (N = 36), triple antibiotic paste (TAP) was used. Bacteriologic samplings were collected before and after exposure to intra-canal medicaments. After the disinfection period (3 weeks), revascularization was induced in all experimental teeth. Each group was subdivided according to the root canal orifice plug into: subgroup A (N = 18), propolis paste was used and subgroup B (N = 18), mineral trioxide aggregates (MTA) was used. Each subgroup was further subdivided according to the evaluation period into 3 subdivisions (6 teeth each): subdivision 1; after 2 weeks, subdivision 2; after one month and subdivision 3; after 2 months. Positive control group had 12 teeth with induced untreated periapical pathosis. Negative control group had 12 untouched sound teeth. All teeth were evaluated with radiography and histology. The bacteriologic and radiographic data were analyzed using repeated measures ANOVA and post-hoc Tukey tests. The histologic data were analyzed using Kruskal-Wallis test, Mann-Whitney U test with Bonferroni's adjustment and Chi-square test. The significance level was set at P ≤ .05., Results: There was no significant difference in the antibacterial effectiveness between TAP and propolis groups (P > .05). In all subdivisions, there was no significant difference between the experimental groups in terms of increase in root length and dentin thickness, decrease in apical closure, new hard tissue formation, vital tissue formation inside the pulp canal and apical closure scores (P > .05)., Conclusion: Propolis can be comparable with TAP as a disinfection treatment option in regenerative endodontic. As a root canal orifice plug after revascularization of necrotic immature permanent teeth in dogs, propolis induces a progressive increase in root length and dentin thickness and a decrease in apical diameter similar to those of MTA.

Direct visualization of the spatial relationships of the dental pulp tissue at the whole-organ has remained challenging. CLARITY (Clear Lipid-exchanged Acrylamide Tissue hYdrogel) is a tissue clearing method that has enabled successful 3-dimensional (3D) imaging of intact tissues with high-resolution and preserved anatomic structures. We used CLARITY to study the whole human dental pulp with emphasis on the neurovascular components. Dental pulps from sound teeth were CLARITY-cleared, immunostained for PGP9.5 and CD31, as markers for peripheral neurons and blood vessels, respectively, and imaged with light sheet microscopy. Visualization of the whole dental pulp innervation and vasculature was achieved. Innervation comprised 40% of the dental pulp volume and the vasculature another 40%. Marked innervation morphological differences between uni- and multiradicular teeth were found, also distinct neurovascular interplays. Quantification of the neural and vascular structures distribution, diameter and area showed that blood vessels in the capillary size range was twice as high as that of nerve fibers. In conclusion whole CLARITY-cleared dental pulp samples revealed 3D-morphological neurovascular interactions that could not be visualized with standard microscopy. This represents an outstanding tool to study the molecular and structural intricacies of whole dental tissues in the context of disease and treatment methods.

Introduction: The aim of this work was to assess and compare changes in pulp blood flow (PBF) and pulp sensibility (PS) after surgically assisted rapid maxillary expansion (SARME) and rapid orthopedic maxillary expansion (OME)., Methods: Ten patients requiring SARME and 10 requiring OME had the pulp status of their maxillary incisors and canines assessed with the use of laser Doppler flowmetry, electric pulp testing (EPT), and CO 2 snow. The SARME group was assessed at T1-S (before surgery), T2-S (after surgery, before expansion), T3-S (after surgery, at completion of expansion), and T4-S (3 months after surgery). The OME group was assessed at T1-O (before expansion), T2-O (after rapid expansion), and T3-O (3 months after expansion commencement). Relationships between PBF/PS and the procedures, assessment times, and tooth types were evaluated., Results: In the SARME group, surgery did not cause significant (P ≥0.05) reduction in PBF, maxillary expansion did cause significant (P ≤0.05) reduction in PBF, pretreatment PBF was reestablished by T4-S, and nonresponses to both EPT and CO 2 peaked at T2-S. In the OME group, rapid expansion caused significant (P ≤0.05) reduction in PBF, pretreatment PBF was reestablished by T3-O, and all teeth responded to at least 1 of EPT or CO 2 at each assessment time., Conclusions and Clinical Implications: Within the study's limitations, it can be concluded that both SARME and OME induce reduction but not elimination of PBF to maxillary anterior teeth and therefore do not cause loss of pulp vitality; surgery for SARME does not significantly reduce PBF to maxillary anterior teeth, rather it is the process of maxillary expansion that significantly reduces PBF in SARME patients; and caution when using CO 2 and EPT tests alone to assess pulp status after SARME is warranted because the capacity for CO 2 or EPT to provide negative sensibility responses despite the presence of PBF was observed., (Copyright © 2019 American Association of Orthodontists. All rights reserved.)

Objectives: We aimed to accelerate angiogenesis in pulp regeneration by modulating ephrinB2 expression in stem cells from apical papilla (SCAPs)., Materials and Methods: Stem cells from apical papilla were transducted with ephrinB2-lentiviral expression vector (ephrinB2-SCAPs) in experimental group and green fluorescent protein (GFP-SCAPs) in control group. The transduction efficiency was confirmed by real-time PCR and Western blot assays. MTT assay was performed to detect the proliferative capacity of SCAPs after transduction. In vitro Matrigel assay and in vivo Matrigel plug assay were carried out to evaluate the angiogenic capacity., Results: Results showed that ephrinB2-SCAPs had significantly higher ephrinB2 expression than GFP-SCAPs. EphrinB2-SCAPs upregulated vascular endothelial growth factor (VEGF) secretion under hypoxia. In vitro Matrigel assay demonstrated that human umbilical vein endothelial cells (HUVECs) cocultured with ephrinB2-SCAPs under hypoxia formed vascular-like structures earlier than GFP-SCAPs. Animal experiments confirmed that SCAPs co-transplanted with HUVECs enabled to generate greater amount of blood vessels than SCAPs alone. EphrinB2-SCAPs produced increased number of blood vessels with references to GFP-SCAPs, and those co-transplanted with HUVECs generated vessels with larger and functional tubule volumes., Conclusions: Regulating ephrinB2 expression in SCAPs may act as a new avenue for enhancing angiogenesis in dental pulp regeneration., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

The regeneration of bone tissue is an active area of research, and future clinical applications are expected. Here, to establish new bone graft materials and an experimental bone tissue model, we generated united compact and spongy bone tissues containing vascular networks from human dental pulp stem cells in vitro. We applied the cell bead and cell sheet methods to construct three-dimensional bone tissue, which was cultured using a circumfusion apparatus for 30 days. Using micro-computed tomography, we assessed structural differences between compact and spongy bone. Histological examinations revealed the presence of bone lacunae containing osteocytes, Haversian canal-like structures, and extensive vascularization. Furthermore, tartrate-resistant acid phosphatase (TRAP) staining-positive osteoclast-like cells were also observed. Thus, the bone tissue generated using this method closely resembles native bone tissue and may possess bone remodeling ability. We successfully generated bone tissue containing blood vessel networks in vitro using this method. The generated bone tissue will likely be highly applicable to medical care, the study of osteogenesis, drug-screening assays, and drug development for bone tissue.

It was shown that the intensity of morphological changes in the dental system tissues (periodontium and pulp) of ISIAH rats depends on the mode of stress exposure. Acute stress was associated with a significant increase in the area of periodontal and pulp vessels, a decrease in the area of connective tissue of these components, and an increase in the thickness of the vascular endothelium. Chronic stress in these animals induced an increase in the thickness of the endothelial layer of the periodontal and pulp vessels, fibromatosis (increase in the number of fibroblasts), and a sharp decrease in the level of odontoblasts.

The aim of this study was to investigate the effect of prolonged release of iloprost, a prostacyclin analog, on angiogenesis and dental pulp healing in a rat model of mechanical pulp exposure. The profile of iloprost release from poly (lactic-co-glycolic) acid (PLGA) microspheres was evaluated, and expression of vascular endothelial growth factor (VEGF) mRNA was determined. The molars of rats were subjected to mechanical pulp exposure and 5 different forms of treatment: Ca(OH) 2 , PLGA (blank), iloprost, and iloprost/PLGA. Blood flow was determined at 0, 3, and 7 days using laser Doppler flowmetry. After 30 days, the tooth specimens were collected, and subjected to micro-CT and immunohistological analysis. The results showed that iloprost release from the microspheres was prolonged for 4 days, and that the treatment increased tooth blood flow for up to 7 days. At 30 days, an increase of mineralized tissue formation and dentin bridge formation was observed in the iloprost and iloprost/PLGA microsphere groups. VEGF expression was significantly increased in the iloprost/PLGA microsphere group relative to the other groups. In conclusion, this PLGA microsphere iloprost delivery system significantly increased dental pulp blood flow in a prolonged manner and increased tertiary dentin formation in this rat pulp injury model. Prolonged prostacyclin release could be a potentially useful approach for regeneration of dental pulp.

Objectives: The aim of this study was to determine the effect of intraosseous (IO) anesthesia with 4% articaine and 1:100,000 epinephrine on pulpal blood flow (PBF) and pulpal anesthesia of mandibular first molars and canines in human subjects., Materials and Methods: Ten healthy volunteers with intact mandibular first molar and canine were given an osteocentral technique of IO injection using the Quick Sleeper 5 system and 4% articaine with 1:100,000 epinephrine at distal site of mandibular first molar. The PBF was monitored by a laser Doppler flowmeter (LDF). Pulpal anesthesia was assessed with an electric pulp tester (EPT)., Results: IO injection caused a decrease in PBF in molars from 6.31 ± 3.85 perfusion units (P.U.) before injection to 2.51 ± 2.53 P.U. 1 min after injection (P < 0.001). The percentage reduction in PBF was 60% after 1 min and PBF returned back to the baseline after 45 min. No significant reduction in PBF was observed in the canines (P = 0.212). For pulpal anesthesia in the molars, the mean onset was 2.40 ± 0.84 min and the mean duration was 38 ± 16.19 min. In the canines, there was a decrease in the sensitivity to EPT but complete pulpal anesthesia was not achieved., Conclusions: IO injection distal to mandibular first molar caused a decrease in PBF and successful pulpal anesthesia in first molar, but not in canine. Both PBF and EPT readings returned to normal, suggesting that pulpal ischemia may not occur., Clinical Relevance: IO anesthesia is safe to use as a primary technique in teeth with normal pulp.

Objectives: To evaluate local effect of gaseous ozone on bacteria in deep carious lesions after incomplete caries removal, using chlorhexidine as control, and to investigate its effect on pulp vascular endothelial growth factor (VEGF), neuronal nitric oxide synthase (nNOS), and superoxide dismutase (SOD)., Materials and Methods: Antibacterial effect was evaluated in 48 teeth with diagnosed deep carious lesion. After incomplete caries removal, teeth were randomly allocated into two groups regarding the cavity disinfectant used: ozone (open system) or 2% chlorhexidine. Dentin samples were analyzed for the presence of total bacteria and Lactobacillus spp. by real-time quantitative polymerase chain reaction. For evaluation of ozone effect on dental pulp, 38 intact permanent teeth indicated for pulp removal/tooth extraction were included. After cavity preparation, teeth were randomly allocated into two groups: ozone group and control group. VEGF/nNOS level and SOD activity in dental pulp were determined by enzyme-linked immunosorbent assay and spectrophotometric method, respectively., Results: Ozone application decreased number of total bacteria (p = 0.001) and Lactobacillus spp. (p < 0.001), similarly to chlorhexidine. The VEGF (p < 0.001) and nNOS (p = 0.012) levels in dental pulp after ozone application were higher, while SOD activity was lower (p = 0.001) comparing to those in control pulp., Conclusions: Antibacterial effect of ozone on residual bacteria after incomplete caries removal was similar to that of 2% chlorhexidine. Effect of ozone on pulp VEGF, nNOS, and SOD indicated its biocompatibility., Clinical Relevance: Ozone appears as effective and biocompatible cavity disinfectant in treatment of deep carious lesions by incomplete caries removal technique.

Objective: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces., Material and Methods: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations. The main observed alterations were related to hemodynamic pulp characteristics, such as presence of thrombosis, vascular congestion and hemorrhages. The hemodynamic alterations were statistically evaluated by Shapiro-Wilk normality test and analysis of variance by the Kruskall-Wallis test., Results: There was no significant differences observed between groups in the different types of applied forces and duration of ITM (vascular congestion, p=1.000; hemorrhage, p=0.305; thrombosis, p=1.000)., Conclusions: Pulp tissue alterations resulting from ITM were limited to hemodynamic events, without progressing to irreversible degeneration, regardless of the type of force applied.

Background/aim: Pulp necrosis is a frequent complication following dental trauma. The diagnosis of the state of the dental pulp can be challenging as most commonly used diagnostic tools are subjective and rely on a response from the patient, potentially making their use unreliable, especially in the child population. The aim of the study was to systematically review the evidence on the use of laser Doppler flowmetry in the assessment of the pulp status of permanent teeth compared to other sensibility and/or vitality tests., Methods: A systematic literature search, using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, www.clinicaltrials.gov and www.controlled-trials.com, in addition to citation and manual reference list searches, was conducted up to 15 th January 2018. A risk of bias assessment was performed using the quality assessment for diagnostic accuracy studies tool (QUADAS-2) with all steps performed independently by two reviewers., Results: Four studies with a high risk of bias were included in the final analysis. Laser Doppler flowmetry was reported to be more accurate in differentiating between teeth with normal pulps and pulp necrosis with a sensitivity of (81.8%-100%) and specificity of 100% in comparison to other vitality tests such as pulp oximetry (sensitivity = 81.3%, specificity = 94.9%) and sensibility tests such as electric pulp testing (sensitivity = 63.3%-91.5%, specificity = 88%-100%)., Conclusion: Despite the higher reported sensitivity and specificity of laser Doppler flowmetry in assessing pulp blood flow, these data are based on studies with a high level of bias and serious shortfalls in study designs. More research is needed to study the effect of different laser Doppler flowmetry's parameters on its diagnostic accuracy and the true cut-off ratios over which a tooth could be diagnosed as having a normal pulp., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: The aim of the present study was to evaluate the possibility of regaining pulp sensibility in mature necrotic teeth using modified regenerative endodontic procedures by inducing bleeding in root canals and using platelet-rich fibrin (PRF)., Methods: Fifteen patients with necrotic pulp with symptomatic or asymptomatic apical periodontitis were included. At the first visit, the tooth was anesthetized, and an access cavity was performed. Mechanical preparation of root canals was performed using the standardized technique reaching apical canal preparation to K-file size #60-80. Double antibiotic paste was injected into the canal, and the cavity was temporarily sealed using glass ionomer cement. Three weeks from the first visit, regenerative endodontic procedures were performed by inducing bleeding, and a freshly prepared PRF membrane was placed in the canal. White mineral trioxide aggregate was placed directly over the PRF matrix, and the tooth was restored with a glass ionomer cement base and resin composite restoration. The electric pulp test was used to record if the teeth included in the study regained sensibility or not every 3 to 12 months follow-up. Readings at different times were compared as categoric qualitative data using the chi-square test and compared as means and standard deviations using the analysis of variance test., Results: Readings of tooth sensibility revealed a highly significant difference (P < .0001) between baseline and the 12-month follow-up period., Conclusions: The presence of sensibility is indicative of the formation of vital pulplike tissue. Reestablishing real pulp tissue after regenerative endodontic treatment is debatable and still needs high level of evidence with large-scale investigations., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To compare the clinical treatment efficiency of platelet-rich fibrin (PRF) assisted revascularization and traditional revascularization in immature permanent teeth., Methods: Eighteen non-vital immature permanent teeth of sixteen patients which were diagnosed as necrotic pulpitis with (or without) periapical inflammations were treated with PRF assisted revascularization. Twenty-two teeth non-vital immature permanent teeth of twenty patients which were diagnosed as necrotic pulpitis with (or without) periapical inflammations were treated with traditional revascularization. All the cases were accorded with inclusive criteria and were treated at Pediatric Dentistry of Peking University School and Hospital of Stomatology. The cases were followed up clinically and radiographically at regular intervals. Clinical examinations and periapical radiographs were recorded and analyzed. Clinical success rate was evaluated based on the clinical and radiographic findings. The changes of root length, dentine wall thickness and apical foramen width of the teeth from the two groups were measured and compared according to the preoperative and by recalling the periapical radiographs., Results: The cases were followed up for 6-16 months. Clinically, totally 17 out of the 18 teeth in PRF group and 21 out of the 22 teeth in traditional group were asymptomatic with no sensitivity to percussion or palpation. PRF group tended to be more effective than traditional group clinically without significant differences (P=0.446). Radiographically, 15 out of the 18 teeth in PRF group and 15 out of the 22 teeth in traditional group displayed that the roots developed, showing that root length and dentine wall thickness increased and apical foramen closed. There was a marked difference in dentine wall thickening in PRF group in comparison with traditional group (P=0.039). However, the changes of root length increasing (P=0.411) and apical foramen width closure (P=0.737) were comparable in both groups. The result in electric pulp test (P=0.517), root canal calcification (P=0.324) and crown discolor (P=0.386) were also comparable in the two groups., Conclusion: PRF assisted revascularization and traditional revascularization in non-vital immature permanent teeth which were diagnosed as necrotic pulpitis with (or without) periapical inflammations resulted in similar clinical outcomes. Both methods showed good prognosis. PRF revascularization seemed to have better effect on dentine wall thickening than traditional method.

This report describes the case of a 52-year-old male patient who exhibited suspicious pulsation patterns during pulpal blood flow assessment using Doppler ultrasound. Initially, he was not aware of his cardiovascular problem; however, after referral to a medical clinic, he was diagnosed with atrial fibrillation. The patient was injured in a motor vehicle accident and referred to our clinic for management of multiple traumatized teeth. On clinical examination, several teeth exhibited negative responses to cold and electrical sensibility tests. For accurate diagnosis, pulpal blood flow assessment using a Doppler ultrasound device was performed. During the tests, irregular pulsation patterns were detected, indicating the possibility of a cardiovascular problem. As he denied any history of cardiovascular problems, he was recommended to visit a medical doctor for further evaluation. The following day, he visited a medical clinic, and a 12-lead electrocardiogram was performed. He was ultimately diagnosed with atrial fibrillation with idioventricular rhythm, and was started on anticoagulant medication for prevention of thrombogenesis, which is a possible complication of atrial fibrillation. As presented in this case, Doppler ultrasound can provide useful information, not only about blood flow in the dental pulp, but also about an individual's pulsation rhythm. When a patient presents with irregular pulsation patterns in certain situations, the possibility of cardiovascular problems should be considered.

Recently, various levels of success have been achieved in dental pulp and dentin regeneration using latest techniques such as pulp revascularization, stem cell transplantation and cell homing. These cutting-edge technologies utilize stem cell mobilization, homing and directional differentiation, stem cell sub-population isolation, expansion and transplantation, modification and optimization of biomaterials and/or synergetic effects of biological cues. The objective of this review is to identify approaches for clinical translation and improve the success rates of pulp regeneration. We will focus on either basic and clinical research progress of dental pulp revascularization, or translational challenges and strategies of stem cell transplantation and cell homing in dental pulp regeneration.

Objective: This study aimed to explore the effects of concentrate growth factor extracts (CGFe) on human umbilical vein endothelial cells (HUVECs) in vitro., Methods: Concentrate growth factor (CGF) were prepared from the peripheral blood of healthy donors, followed by CGFe. Four groups were designed based on cell culture medium, as follows: 2%CGFe, 5%CGFe, 10%CGFe, and control. The proliferation activity of HUVECs was detected by cell cycle and CCK-8 assays. The migration of HUVECs was detected by scratch assay. The mRNA expression levels of vascular endothelial growth factor (VEGF), chemokine receptor 4 (CXCR4), and platelet derived growth factor (PDGF) were examined by quantitative real time polymerase chain reaction (qRT-PCR)., Results: Results of CCK-8 and cell cycle assays showed that CGFe promoted the proliferation capability of HUVECs in a dose-dependent manner, and the data had statistical significance among four groups (P<
0.05). The cell migration assay indicated that CGF accelerated wound closure in a dose-dependent manner after 12 h of culture (P<0.05). The results of qRT-PCR showed that CGF upregulated the expression levels of VEGF, CXCR4, and PDGF in HUVECs., Conclusions: CGFe can promote the proliferation, migration, and angiogenic differentiation of HUVECs. Thus, CGF might be an appropriate cure for dental pulp revascularization.

In the context of tooth trauma, mostly the maxillary central front teeth are involved, whereby their roots are in some cases still in the developing stage (immature). Depending on the type of trauma, a necrosis of the pulp is the consequence or at least foreseeable. In order to preserve such a tooth, an endodontic therapy is inevitable. The disadvantage of conventional endodontic therapy methods of immature teeth (apexification, apexogenesis) is the root growth stop. Alternatively, the regeneration/revascularisation of the dental pulp (RP) was suggested, that allows a further root growth. The aim of this case report is to present the procedure of a RP-therapy and to suggest a step-by-step manual.

Introduction: Angiogenesis is a key determinant in dental pulp regeneration. Iloprost is a synthetic prostacyclin that promotes angiogenesis. A three-dimensional culture that mimics the in vivo condition has been used in tissue engineering. This study investigated the effect of iloprost on promoting dental pulp angiogenesis by using the tooth slice organ culture system., Methods: Tooth slices with intact pulp tissue were cut from molars extracted from 12 patients. Dental pulp tissue viability was determined by live/dead staining. The tooth slices were cultured with iloprost for 1 or 3 days. The microvessel density and expression of vascular endothelial growth factor were determined by immunohistochemical staining. Collagen density was determined by using Masson trichrome and immunofluorescent staining., Results: The pulp tissue in the tooth slices remained viable when cultured in serum-free medium. Iloprost increased the microvessel density as shown by a higher number of von Willebrand factor-positive cells. A significant increase in vascular endothelial growth factor expression was observed in the tooth slices cultured with iloprost. Iloprost stimulated collagen deposition, and this effect was abolished after inhibition of protein kinase A activity., Conclusions: Human tooth slices provide a valuable and easy-to-obtain model to investigate the effect of bioactive molecules used in dental pulp regeneration. This study showed for the first time that tooth slices could be kept viable under serum-free conditions for up to 3 days. Iloprost promoted angiogenesis, increased new vessel formation, and induced collagen deposition. This study proposes the clinical value of iloprost as a drug for inducing angiogenesis that can increase the success of pulp regeneration., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: Up-regulation of odontogenic differentiation, dentin formation, and angiogenesis in dental pulp are key factors in vital pulp therapy. The aim of this study was to investigate whether leptin could promote odontogenic differentiation and angiogenesis in human dental pulp cells (hDPCs). In addition, the involvement of the intracellular signaling pathway in these effects was determined., Methods: The viability of hDPCs treated with leptin was examined using the water soluble tetrazolium salt-1 assay. Real-time polymerase chain reaction was performed to determine messenger RNA (mRNA) expression levels of odontogenic and angiogenic markers. Western blot analysis was used to measure odontogenic and angiogenic protein expression levels and assess mitogen-activated protein kinase (MAPK) pathway involvement. Alkaline phosphatase (ALP) and alizarin red staining were used to evaluate expression levels of ALP and calcified nodule formation after treatment with leptin and/or the presence of MAPK inhibitors., Results: All concentrations of leptin used in this study did not significantly affect the viability of hDPCs. However, mRNA and protein levels of odontogenic and angiogenic markers, ALP activity, and calcified nodule formation were significantly increased in the leptin-treated group compared with those in the control group. Leptin enhanced phosphorylation of extracellular signal-related kinases, c-Jun N-terminal kinase, and p38 mitogen-activated protein kinases within 5 minutes after treatment. However, leptin-induced dentin sialophosphoprotein and vascular endothelial growth factor protein expression and mineralization were appreciably blocked by the presence of MAPK inhibitors., Conclusions: Leptin can induce angiogenesis, odontogenic differentiation, and mineralization in hDPCs via activating the MAPK signaling pathway., (Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the percentage of the blood flow signal that is derived from dental pulp when recording from exposed dentine in a human premolar., Design: Recordings were made from 7 healthy teeth in 5 subjects (aged 22-33 yr.) with a laser Doppler flow meter (Periflux 4001) using either a red (635 nm) or an infrared (780 nm) laser. After exposing dentine above the buccal pulpal horn (cavity diam. 1.6 mm, depth 3 mm) and isolating the crown with opaque rubber dam, blood flow was recorded alternately with infrared or red light from the exposed dentine under four conditions: before and after injecting local anaesthetic (3% Mepivacaine without vasoconstrictor) (LA) over the apex of the root of the tooth; after exposing the pulp by cutting a buccal, class V cavity in the tooth; and after sectioning the coronal pulp transversely through the exposure., Results: There was no significant change in mean blood flow recorded with either light source when the tooth was anaesthetized or when the pulp was exposed. After the pulp had been sectioned, the blood flow recorded with infrared light fell by 67.8% and with red light, by 68.4%. The difference between these effects was not significant., Conclusions: When recording blood flow from exposed coronal dentine with either infrared or red light in a tooth isolated with opaque rubber dam, about 68% to the signal was contributed by the pulp. The signal:noise ratio was better with infrared than red light, and when recording from dentine than enamel., (Copyright © 2017 Elsevier Ltd. All rights reserved.)