Association between pulp stones and systemic diseases: a case-control study

Introduction: Pulp stones (PS) are calcifications commonly found in the pulp tissue that may be associated with systemic diseases. Objective: To evaluate the association between PS and systemic diseases. Methods: A case-control study with the inclusion of individuals from 18 to 65 years of age, of both sexes. Analysis was made of 1047 digital panoramic radiographs. The controls could not have any teeth with PS; the cases were the contrary. A questionnaire comprising demographic, habit, and general health (diabetes, problems with blood vessels, altered cholesterol level, heart attack, kidney or gallbladder stone, arthritis, or autoimmune disease, and for women, endometriosis, and ovarian cyst). Data were submitted to the Student's t-test to identify differences between groups about sex and age. The Chi-square test was applied to the cross-tabulation. The analyses were performed using SPSS®, version 25.0, with a 5% significance level. Results: 490 patients participated (242 cases and 248 controls). There was no difference between groups for the sex (p=0.966) and age (p=0.186). Only "kidney stone" was associated with the case group (p=0.001), being almost three times higher when compared to the control group. No significant differences were found in females about the presence or absence of PS (p>0.05). Conclusion: In this research, it is suggested the existence of an association between kidney stones and the presence of pulp stones.

Identificação de Enterococcus SPP e Enterobacteriaceae em canais radiculares com infecção primária e secundária ou persistente / Identification of Enterococcus spp and Enterobacteriaceae in root canals with primary and secondary or persistent infection

O objetivo do presente estudo foi identificar microrganismos das espécies Enterococcus spp e Enterobacteriaceae em dentes com canais radiculares infectados portadores de infecção primária e/ou secundária/persistente. Métodos: A amostra do presente estudo foi de 23 pacientes que apresentaram necessidade de tratamento ou retratamento endodôntico. Foram coletadas amostras de 28 dentes infectados usando pontas de papel absorventes estéreis, transportadas em solução salina, diluídas, plaqueadas e incubadas em estufa de cultura bacteriológica. Para o crescimento de microrganismos foram utilizados jarros com gerador de atmosfera de anaerobiose. Colônias microbianas foram isoladas, caracterizadas e identificadas. Os dados coletados foram estatisticamente analisados com a utilização do software SPSS for Windows 10.0 (SPSS Inc., USA). Resultados: Foi isolada somente uma cepa do gênero Enterococcus spp, e nenhuma espécie do gênero Enterobacteriaceae. Das coletas microbiológicas realizadas em 28 canais radiculares, todas apresentaram crescimento microbiano em anaerobiose. Dezoito dentes apresentavam necrose pulpar e lesão periapical. Os outros 10 dentes já haviam recebido tratamento endodôntico prévio e em 6 destes houve constatação de lesão periapical, sendo que nos outros 4, não. Conclusão: Nas condições experimentais do presente estudo, pode-se concluir que não houve correlação da presença de espécies microbianas das famílias Enterococcus spp e/ou Enterobacteriaceae com infecção primária ou secundária do canal radicular.

The objective of the present study was to identify microorganisms of the Enterococcus spp and Enterobacteriaceae species in teeth with infected root canals with primary and/or secondary/persistent infection. Methods: The sample of the present study consisted of 23 patients who required endodontic treatment or retreatment. Samples of 28 infected teeth were collected using sterile absorbent paper points, transported in saline solution, diluted, plated and incubated in a bacteriological culture oven. For the growth of microorganisms, jars with an anaerobic atmosphere generator were used. Microbial colonies were isolated, characterized and identified. The collected data were statistically analyzed using the SPSS for Windows 10.0 software (SPSS Inc., USA). Results: Only one strain of the genus Enterococcus spp was isolated, and no species of the genus Enterobacteriaceae. From the microbiological collections carried out in 28 root canals, all showed microbial growth in anaerobic conditions. Eighteen teeth had pulp necrosis and periapical lesion. The other 10 teeth had already received previous endodontic treatment and in 6 of them there was a periapical lesion, and in the other 4, no. Conclusion: Under the experimental conditions of the present study, it can be concluded that there was no correlation between the presence of microbial species of the Enterococcus spp and/or Enterobacteriaceae families with primary or secondary root canal infection.

Células tronco e endodontia regenerativa / Stem cells and regenerative endodontics

Desde o incremento das pesquisas das células-tronco em 1961, por cientistas canadenses, os avanços em estudos, pesquisas e o desenvolvimento de novos tratamentos com esse tipo de recurso se mostram promissores. O uso de células-tronco é uma grande aposta tanto para a medicina quanto para a odontologia regenerativa. Os tratamentos com essa terapia podem oferecer mais qualidade de vida para as pessoas. O potencial dessas células tão especiais se encontra em duas características peculiares: elas são capazes de se multiplicarem e de se diferenciarem em outros tipos de células, como de tecidos, cartilagens e neurônios. É dessa maneira que elas têm um papel fundamental para estudos e tratamentos relacionados à regeneração. O uso de células-tronco na Odontologia torna possível diferentes processos odontológicos que oferecem mais qualidade de vida ao paciente. Isso porque fatores como defeitos genéticos, hábitos nocivos, cáries dentárias e perdas precoces dos dentes contribuem com a perda de dentes ao longo da vida. No início do século XXI, por volta dos anos de 2005, 2006, pesquisadores começaram a publicar em revistas internacionais da área uma nova técnica baseada no uso de célulastronco existentes no osso de sustentação dos dentes e na articulação dento alveolar. Esta técnica, chamada de Revascularização, promove o aparecimento de um novo tecido pulpar sadio, devolvendo ao dente sua vitalidade e higidez(AU)

Since the increase in stem cell research in 1961 by Canadian scientists, advances in studies, research and the development of new treatments with this type of resource have shown promise. The use of stem cells is a big bet for both medicine and regenerative dentistry. Treatments with this therapy can offer more quality of life for people. The potential of these very special cells lies in two peculiar characteristics: they are able to multiply and differentiate into other types of cells, such as tissues, cartilage and neurons. It is in this way that they play a key role for studies and treatments related to regeneration. The use of stem cells in dentistry makes possible different dental processes that offer more quality of life to the patient. That's because factors such as genetic defects, harmful habits, tooth decay, and early tooth loss all contribute to lifelong tooth loss. At the beginning of the twenty-first century, around the years 2005, 2006, researchers began to publish in international journals of the area a new technique based on the use of existing stem cells in the supporting bone of the teeth and in the alveolar tooth joint. This technique, called Revascularization, promotes the appearance of a new healthy pulp tissue, returning to the tooth its vitality and hygiene(AU)

Neural and Neural Crest-Derived Stem Cell Distribution in the Adult Human Dental Pulp / Distribución de Células Madre Neurales y Derivadas de la Cresta Neural en la Pulpa Dental Humana Adulta

SUMMARY: Despite comprehensive studies and reports about the properties of dental pulp stem cells (DPSCs) in vitro, we still need to confirm whether these in vitro characteristics coincide with the nature of DPSCs in situ. The anatomical location of DPSCs populations in the dental pulp has yet to be investigated. Moreover, the mesenchymal DPSCs have been much more studied than the neural crest-derived DPSCs. In this study, well-recognized neural/neural crest stem cell markers NCAM1, Nestin, SNAIL/SLUG, SOX9, and S100 are being investigated by immunohistochemistry to localize the precise location of these populations of DPSCs within the human adult dental pulp.All previously mentioned markers were expressed in the dental pulp, and their intensity and location of expression were reported.

A pesar de estudios e informes exhaustivos sobre las propiedades de las células madre de la pulpa dental (DPSC) in vitro, todavía necesitamos confirmar si estas características in vitro coinciden con la naturaleza de las DPSC in situ. La ubicación anatómica de las poblaciones de DPSC en la pulpa dental aún no se ha investigado. Además, las DPSC mesenquimales han sido mucho más estudiadas que las DPSC derivadas de la cresta neural. En este estudio, se están investigando mediante inmunohisto química marcadores de células madre de la cresta neural/ neural NCAM1, Nestin, SNAIL/SLUG, SOX9 y S100 para localizar la ubicación precisa de estas poblaciones de DPSC dentro de la pulpa dental humana adulta. Todos los marcadores mencionados anteriormente se expresaron en la pulpa dental y se informó su intensidad y ubicación de expresión.

Mechanism of Chir99021 regulating Wnt / β⁃catenin signaling pathway inhibiting osteogenic differentiation of rat dental pulp stem cells / 解剖学报

Objective To explore the effect and mechanism of Chir99021 on osteogenic differentiation of rat dental pulp stem cells. Methods Primary rat dental pulp stem cells were isolated from rat dental pulp and verified by fluorescence immunoassay. Different concentrations of Chir99021 were set, and the cell proliferation was detected by CCK⁃8 to select the optimal concentration. Osteogenic differentiation was detected by alizarin red staining. The expression of osteogenic differentiation related genes and proteins recombinant wingless type MMTV integration site famity member 1 (Wnt1), Wnt3a and Wnt3a β⁃expression of catenin, axis inhibition protein 2(Axin 2), dentin sialophosphoprotein(OCN) and dentin matrix acidic phosphoprotein 1(DMP1) was detected by Real⁃time PCR and Western blotting. Results The positive expression of dentin sialophosphoprotein (DSPP) and vimentin indicated that rat dental pulp stem cells were successfully isolated. After osteogenic induction of rat dental pulp stem cells, calcium deposits significantly increased with the addition of glycogen synthase kinase⁃3β(GSK⁃3β) inhibitor Chir99021, calcium deposits were significanted reduced. After osteogenic differentiation of rat dental pulp stem cells, the expression of Wnt1, Wnt3a, β⁃catenin, Axin2, OCN and DMP1 increased, while the expression of Wnt1, Axin2, OCN and DMP1 decreased with the addition of Chir99021. Conclusion Chir99021 can inhibit the osteogenic differentiation of rat dental pulp stem cells after 7 days of induction.

Effect of low concentration of sodium fluoride on osteogenic/odontogenic differentiation of human dental pulp cells / 口腔疾病防治

Objective@#To study the effect of low concentrations of sodium fluoride on the osteogenic/odontogenic differentiation of human dental pulp cells (hDPCs) in vitro.@*Methods@#This study was reviewed and approved by the Ethics Committee. hDPCs were cultured using a modified tissue explant technique in vitro. The effects of different concentrations of sodium fluoride on the proliferation of hDPCs were measured by methylthiazol tetrazolium (MTT) assay. Appropriate concentrations were added to the osteogenic/odontogenic differentiation induction medium, and the cells were induced in vitro. Alizarin red S staining was used to detect the osteoblastic/odontogenic differentiation ability of the cells, and the mRNA expression of the key differentiation factors was detected by RT-qPCR. Moreover, the expression of key molecules of endoplasmic reticulum stress (ERS) was detected by RT-qPCR and Western blot. The data were analyzed with the SPSS 18.0 software package.@*Results@#Low concentration of NaF (0.1 mmol/L) could stimulate cell proliferation in vitro, while a high concentration (5-10 mmol/L) could inhibit cell proliferation (P<0.05). According to the literature and the experimental data, 0.1 mmol/L NaF was selected as the following experimental concentration. The levels of alizarin red S staining were increased after NaF induction of mixed osteogenic/odontogenic differentiation in vitro. The mRNA expression levels of key molecules for osteogenic/odontogenic differentiation, dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP) and osteocalcin (OCN), were increased (P<0.05). The mRNA levels of ERS markers (splicing x-box binding protein-1 (sXBP1), glucose-regulated protein 78 (GRP78) and activating transcription Factor 4 (ATF4) were increased in NaF-treated cells. The protein expression levels of key ER stress molecules (phosphorylated RNA-activated protein kinase-like ER-resident kinase (p-PERK), phosphorylated eukaryotic initiation factor-2α (p-eIF2α) and ATF4) were higher in NaF-treated cells.@*Conclusion@#A low concentration of NaF promotes the osteogenic/odontogenic differentiation of hDPCs and increases the level of ER stress.

Epidermoid cyst in the right mandible: a case report and literature review / 口腔疾病防治

Objective@#To discuss the possible etiology, pathogenesis, clinical features, diagnosis and treatment of epidermoid cysts of the jaw and to provide a reference for clinical diagnosis and treatment.@*Methods@#A case of an epidermoid cyst in the right mandible with retained deciduous teeth and succedaneous impacted teeth was reviewed and analyzed in combination with the relevant literature.@*Results@#A patient presented with a mass in the right mandible that had persisted for 1 month after being found at imaging examination. Tooth 83 was retained, and tooth 43 was unerupted. Swelling was characterized by no obvious tenderness, fluctuation, or table tennis sensation and was observed in the lingual alveoli of teeth 83, 44, and 45. Imaging revealed a low-density shadow in the apex of teeth 83, 44, 45, and 46, approximately 1.9 cm × 2.6 cm × 1.6 cm in size, which wrapped around the dental crown of tooth 43. Preliminary diagnoses were as follows: right mandibular mass thought to be a dentigerous cyst; impacted tooth 43; and retained primary tooth 83. The mass in the right mandible was removed, and teeth 43 and 83 were extracted under intravenous and inhalation anesthesia. During the operation, the mass was observed to have a thin cyst wall and contained bean-like residue. Histopathological examination indicated an epidermoid cyst in the right mandible. At the 1-week follow-up examination, the patient reported no discomfort, and the surgical area showed good recovery. According to the literature, epidermoid cysts are benign cysts originating from ectopic ectodermal tissue that can occur throughout the body but rarely in the oral cavity and are even extremely rarer in the jaw. Epidermoid cysts of the jaw, which have no specific clinical manifestations, can be confused with odontogenic cysts such as dentigerous cysts and odontogenic tumors. Dental pulp tests and other techniques can serve as a reference for clinicians. The diagnosis is confirmed via histopathology. Surgical removal is a common treatment, with a good prognosis and a low recurrence rate.@*Conclusion@#The principle of treatment for an epidermoid cyst of the jaw is similar to that for a jaw cyst. The prognosis is good when the cyst is removed completely.

Evaluation of different methods of calcium hydroxide removal from root canals with simulated internal resorptions / Avaliação de diferentes métodos de remoção de hidróxido de cálcio de canais radiculares com reabsorções internas simuladas

Objective: This study evaluated different methods of calcium hydroxide (CH) removal from root canals with simulated internal resorptions using microcomputed tomography (micro-CT). Material and Methods: Sixty acrylic resin blocks with simulated root canals and internal resorptions were prepared using a Reciproc R25 file and then filled with CH. The blocks were divided into five test groups (n=12) according to the method used for CH removal: hand files (HF), Easy Clean (EC), passive ultrasonic irrigation (PUI), XP-Endo Finisher (XP), XP-Endo Finisher + PUI (XP+PUI). The blocks were scanned using a SkyScan 1172 scanner before and after CH removal to measure the volume and percentage of CH removal. The OriginPro 2017 software was used for statistical analyses. The level of significance was set at p<0.05 for all tests. Results: No method under study removed all CH. All methods had similar results in the cervical third (P>0.05). The percentage of CH removal was significantly greater in the area of internal resorption and along the total length of the canal in the XP+PUI group (P<0.05). The best results of CH removal were found in the apical third of roots in the XP+PUI and PUI groups (P>0.05). Conclusion: No method removed all CH from the root canals, but the combined XP+PUI method removed more CH than the other methods, especially from the area of the internal resorption(AU)

Objetivo: Este estudo avaliou diferentes métodos de remoção de hidróxido de cálcio (CH) de canais radiculares com reabsorções internas simuladas por meio de microtomografia computadorizada (micro-CT). Material e Métodos: Sessenta blocos de resina acrílica com canais radiculares simulados e reabsorções internas foram preparados com lima Reciproc R25 e posteriormente preenchidos com CH. Os blocos foram divididos em cinco grupos de teste (n=12) de acordo com o método utilizado para remoção de CH: limas manuais (HF), Easy Clean (EC), irrigação ultrassônica passiva (PUI), XP-Endo Finisher (XP), XP -Endo Finalizador + PUI (XP + PUI). Os blocos foram escaneados usando um scanner SkyScan 1172 antes e depois da remoção do CH para medir o volume e a porcentagem de remoção do CH. O software OriginPro 2017 foi utilizado para análises estatísticas. O nível de significância foi estabelecido em p<0,05 para todos os testes. Resultados: Nenhum método em estudo removeu todos o CH. Todos os métodos tiveram resultados semelhantes no terço cervical (P>0,05). A porcentagem de remoção de CH foi significativamente maior na área de reabsorção interna e ao longo do comprimento total do canal no grupo XP+PUI (P<0,05). Os melhores resultados de remoção de CH foram encontrados no terço apical das raízes nos grupos XP+PUI e PUI (P>0,05). Conclusão: Nenhum método removeu todo o CH dos canais radiculares, mas o método combinado XP+PUI removeu significativamente mais CH do que os outros métodos, especialmente da área de reabsorção interna (AU)

The Effect of Restoration Polymerization and Residual Dentine Thickness on Thermal Changes of Pulp Chamber of Immature Permanent Teeth

ABSTRACT Objective: To evaluate the pulpal temperature changes due to the polymerisation of resin and glass ionomer-based materials in dentine thicknesses in immature permanent teeth with open apices. Material and Methods: Forty extracted sound human third molar teeth with open apices were included. The width of the cavities prepared on the occlusal surface was 4×5 mm. The depth was 2 mm in the resin groups. 4 mm in the groups in which glass ionomer liner was applied before composite restoration. The coronal parts of the samples were then placed on an acrylic plate with three gaps for feeding-extraction needles and the thermocouple. The temperature changes were recorded. The data was analyzed by SPSS. Statistical significance was accepted as p<0.05. Results: The temperature increase in the group of 1 mm remaining dentin thickness revealed higher results than the values detected from the 2 mm group (1.01 °C) (p=0.00). The mean values (1.49 °C, 1mm) of temperature changes in only glass ionomer applied group were lower than the avarage values (2.210°C, 1mm) determined in the polymerization process of resin composites with light-emitting diode devices. Conclusion: In a remaining dentin thickness of 1 mm in teeth with open apices, using a glass ionomer liner might be a useful effort for protecting the pulp from the heat generated by polymerisation devices.

Is Cavity Lining Really Necessary After Selective Caries Removal in Primary Teeth?

ABSTRACT Objective: To evaluate the clinical and radiographic response of pulp-dentin complex after selective caries removal with or without pulp lining in primary teeth. Material and Methods: Twenty-four primary molars with deep occlusal caries lesions and without pulpal alterations were selected from children, both genders, aged between 5 and 9 years old. After selective caries removal, the teeth were divided into three groups: without cavity liner (Group I), calcium hydroxide cement - CH (Group II), and Mineral trioxide aggregate - MTA (Group III). The final restoration was performed with resin-modified glass ionomer cement. Clinical and radiographic assessments were conducted at 6-month follow-up. The Kappa test determined intraexaminer reliability. Fisher's exact test evaluated intergroup comparisons (p<0.05). Results: All teeth showed clinical and radiographic success at the 6-month follow-up without statistically significant differences (p>0.05). Conclusion: Selective caries removal without cavity lining was acceptable for deep caries lesions in primary teeth.

Research progress on the physical and chemical properties and application of graphene and its derivatives / 实用口腔医学杂志

Recent studies show that graphene and its derivatives have good physical and chemical properties and biocompatibility,and can promote cell proliferation and stem cell differentiation.The process of pulp regeneration involves the proliferation and differen-tiation of seed cells,suggesting that graphene and its derivatives have the potential applications perspective in pulp regeneration.How-ever,it has not been reported whether the physical and chemical properties of graphene and its derivatives are suitable for pulp cavity or root canal environment and its effect on pulp regeneration seed cells.This article reviews the physical and chemical properties,cyto-logical effects and the application of graphene and its derivatives in tissue engineering,and provides a basis for its application in dental pulp regeneration.

Progress of Pulpal Disease Treatment in Young Permanent Teeth / 华中科技大学学报(医学版)

Young permanent teeth are not fully developed due to their short eruption,characterized by a relatively large pulp cavity,high and pointed pulp horns,and open apical foramina.Due to caries,abnormal tooth development or trauma,the dental pulp may be damaged or infected,which may lead to pulp necrosis and directly affect the normal tooth root formation.Therefore,the treatment of dental pulp disease in young permanent teeth poses a huge clinical challenge.The goal of clinical treatment is to promote continued root development of the affected tooth,thicken the root canal walls,and close the api-cal foramina.This article reviews the treatment options for reversible and irreversible pulpitis caused by pulp exposure,aiming to provide a reference for the treatment of pulp lesions in young permanent teeth,focusing on preserving healthy pulp and pro-moting pulp repair and regeneration.

Recombinant human growth hormone promotes osteogenic differentiation of human dental pulp stem cells / 中国组织工程研究

BACKGROUND:Previous studies have shown that human dental pulp stem cells have good osteogenic differentiation potential and are potential seed cells in bone tissue engineering,and the effect of recombinant human growth hormone on the proliferative osteogenic differentiation of human dental pulp stem cells is still unclear. OBJECTIVE:To explore the effect of recombinant human growth hormone on the proliferation and osteogenic differentiation of human dental pulp stem cells. METHODS:Human dental pulp stem cells were isolated and cultured by tissue block culture method.After screening according to the drug concentration gradient,recombinant human growth hormone containing 10,100,250,500,1 000 μg/L was selected as the experimental group,and 0 μg/L without recombinant human growth hormone was selected as the control group.CCK-8 detection reagents were used on days 1,3,5,and 7 after the drug intervention to detect the proliferation of human dental pulp stem cells.Different concentrations(10,100,250,500,and 1 000 μg/L)of recombinant human growth hormone were added to the osteogenesis induction solution to intervene in human dental pulp stem cells.Alkaline phosphatase activity was detected by alkaline phosphatase staining and semi-quantitative analysis on day 7 of mineralization induction.The mRNA expression levels of osteogenic gene type I collagen,osteocalcin and Runt-related transcription factor 2 were detected by fluorescence quantitative RT-qPCR.Alizarin red staining was performed on day 14 of mineralization induction to detect osteogenic mineralized nodules. RESULTS AND CONCLUSION:(1)CCK-8 assay results showed that from the third day of intervention,the 100,250,500,1 000 μg/L recombinant human growth hormone group could promote the proliferation of human dental pulp stem cells compared with the control group(P<0.01).(2)The alkaline phosphatase activity of human dental pulp stem cells in the 100,250,and 500 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).The number of alizarin-stained mineralized nodules in human dental pulp stem cells in the 100,250 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).Compared with the control group,the mRNA expression of type I collagen and osteocalcin increased in the 250 μg/L recombinant human growth hormone group(P<0.05,P<0.01).mRNA expression of Runt-associated transcription factor 2 increased in the 100 and 250 μg/L recombinant human growth hormone groups(P<0.01).(3)According to the above results,recombinant human growth hormone at a concentration of 250 μg/L is a more suitable concentration to promote the proliferation and osteogenic differentiation of human dental pulp stem cells.

Overexpression of Sema3A promotes osteogenic differentiation of dental pulp stem cells and MC3T3-E1 / 中国组织工程研究

BACKGROUND:Sema3A is a power secretory osteoprotective factor.However,studies about Sema3A-modified dental pulp stem cells(Sema3A-DPSCs)are rare. OBJECTIVE:To explore the osteogenic differentiation ability of Sema3A-DPSCs and their regulatory effect on the osteogenic differentiation of the pre-osteoblast cell line MC3T3-E1. METHODS:First,Sema3A-DPSCs were constructed using a lentivirus infection system carrying the Sema3A gene.Control lentivirus-treated DPSCs(Vector-DPSCs)were used as controls.Sema3A-DPSCs or Vector-DPSCs were co-cultured with proosteoblast line MC3T3-E1 at the ratio of 1∶1 and 1∶3 for 24 hours.Finally,the Sema3A-DPSCs,Vector-DPSCs and their co-cultured cells with MC3T3-E1 were cultured for osteogenic induction and differentiation.Osteogenic gene expression was detected by alkaline phosphatase staining,alizarin red staining and real-time quantitative RT-PCR to evaluate osteogenic differentiation ability. RESULTS AND CONCLUSION:(1)Sema3A mRNA and protein expression levels in Sema3A-DPSCs were significantly up-regulated.The level of secreted Sema3A in cell supernatant was up-regulated.(2)Compared with the Vector-DPSCs,mRNA expressions of osteogenic genes alkaline phosphatase,Runt-related transcription factor 2,osteocalcin and Sp7 transcription factors in Sema3A-DPSCs were up-regulated;the activity of alkaline phosphatase was enhanced,and the formation of mineralized nodules increased.(3)There were no obvious differences in proliferation between Sema3A-DPSCs and Vector-DPSCs.(4)Compared with MC3T3-E1/Vector-DPSCs co-culture system,the expression of MC3T3-E1 osteogenic genes was up-regulated,and the total alkaline phosphatase activity was enhanced and more mineralized nodules were formed in the MC3T3-E1/Sema3A-DPSCs co-culture system.(5)The results suggest that overexpression of Sema3A can enhance the osteogenic differentiation of DPSCs.Overexpression of Sema3A in DPSCs can promote osteogenic differentiation of MC3T3-E1 in the DPSCs/MC3T3-E1 co-culture system.

Effects of aging factors on biological characteristics of dental stem cells / 中国组织工程研究

BACKGROUND:The research of dental stem cells in the fields of regenerative medicine and tissue engineering has been deepening,bringing hope for the repair of tooth-related tissues and the treatment of systemic diseases.However,there is a lack of systematic research and analysis on the biological characteristics of dental stem cells in different age groups. OBJECTIVE:To explore the biological characteristics of the human deciduous tooth and permanent tooth pulp stem cells cultured in umbilical cord blood platelet lysate to provide a reliable basis for human platelet lysates to replace fetal bovine serum. METHODS:The pulp tissues of deciduous teeth,juvenile permanent teeth and adult permanent teeth were taken out and cultured in DMEM/F-12 medium supplemented with 10%fetal bovine serum or different concentrations(5%,10%and 15%)of human platelet lysates.Cell proliferation in the four groups was detected by cytometry.The optimal concentration of human platelet lysates was selected for subsequent experiments.Under the optimal concentration of human platelet lysates,human deciduous tooth and juvenile and adult permanent tooth pulp stem cells were cultured in vitro.The cell growth status was observed under the microscope.The specific antigen on the cell surface was detected by flow cytometry.The cell proliferation ability was tested by the cell counting method and CCK-8 assay.The cell differentiation ability in vitro was observed by a three-line differentiation assay. RESULTS AND CONCLUSION:(1)The cell proliferation rate of the 10%human platelet lysate group was the highest.(2)In all three groups,fusiform fibrous cells grew and expanded from around the tissue block.There was no significant difference between deciduous teeth and juvenile permanent tooth cells,but the adult permanent tooth cells were larger than the deciduous and juvenile permanent tooth cells of the same generation.(3)The results of flow cytometry showed that deciduous teeth,juvenile permanent teeth and adult permanent teeth conformed to the phenotypic characteristics of mesenchymal stem cells.(4)The proliferative capacity of adult permanent dental pulp stem cells was significantly lower than those of deciduous teeth and juvenile permanent dental pulp stem cells(P<0.01).(5)mRNA expressions of osteoblast-related genes alkaline phosphatase and bone morphogenetic protein 2,lipoprotein lipase and peroxisome proliferator-activated receptor γ2,mRNA expressions of chondroblast related gene type II collagen α1 and cartilage oligomeric matrix protein in adult pulp stem cells of permanent teeth were significantly lower than those of deciduous teeth and juvenile permanent teeth pulp stem cells(P<0.01).(6)Compared with adult dental pulp stem cells,human deciduous teeth and juvenile permanent teeth dental pulp stem cells have the stronger proliferative capacity and multidirectional differentiation potential,and are more suitable for clinical research and disease treatment.

Preparation and performance of gelatin modified by methacrylic anhydride/treated dentin matrix bioactive scaffolds / 中国组织工程研究

BACKGROUND:Pulp regeneration has been a hot and difficult research topic in recent years,and the construction of composite bio-scaffolding materials provides new ideas and methods for pulp regeneration. OBJECTIVE:To observe the effect of freeze-dried gelatin modified by methacrylic anhydride/treated dentin matrix bioactive scaffolds on proliferation,migration,and osteogenic differentiation of human dental pulp stem cells. METHODS:The mass ratios of gelatin modified by methacrylic anhydride and treated dentin matrix at 2:1,1:1 and 1:2 were obtained by dispersing different masses of treated dentin matrix into gelatin modified by methacrylic anhydride solution.The gelatin modified by methacrylic anhydride/treated dentin matrix bioactive scaffolds were prepared by vacuum freeze-drying.The microstructure,water absorption,and mechanical properties of the scaffolds were measured.Human dental pulp stem cells were cultured with different mass ratios of scaffold extract and DMEM(control group)to detect cell proliferation and migration.Human dental pulp stem cells were cultured with different mass ratios of scaffold extract + osteogenic induction solution and DMEM + osteogenic induction solution(control group),and their osteogenic ability was analyzed by alkaline phosphatase staining. RESULTS AND CONCLUSION:(1)Under scanning electron microscopy,the scaffolds of the three groups all had porous structures.The porosity of the scaffolds increased with the increase of treated dentin matrix quality,and there was significant difference between the two groups(P＜0.05).The water absorption of scaffolds increased with the increase of treated dentin matrix mass,and there was significant difference between groups(P＜0.05).The compressive strength and shear strength of the scaffold increased with the increase of the mass of treated dentin matrix.(2)CCK-8 assay showed that after 3,5,and 7 days of culture,the cell proliferation absorbance values in the 2:1,1:1,and 1:2 scaffold groups were higher than those in the control group(P＜0.05).The cell proliferation absorbance values increased with the increase of treated dentin matrix mass in the scaffold(P＜0.05).The cell scratch test showed that the cell migration rate in the 2:1,1:1,and 1:2 scaffold groups was higher than that in the control group(P＜0.05),and the cell migration rate increased with the increase of treated dentin matrix mass in the scaffold(P＜0.05).(3)Alkaline phosphatase staining showed that the osteogenic differentiation ability of cells in the 2:1,1:1,and 1:2 scaffold groups was stronger than that in the control group,and the osteogenic ability of cells was enhanced with the increase of treated dentin matrix mass in the scaffold.(4)The results showed that the scaffold with a mass ratio of 1:2 between gelatin modified by methacrylic anhydride and treated dentin matrix was the most suitable for the proliferation and differentiation of dental pulp stem cells.

Effect of pulp revascularization on pulp necrosis with periapical periodontitis in young permanent teeth / 中国基层医药

Objective:To investigate the efficacy of pulp revascularization in the treatment of pulp necrosis with periapical periodontitis in young permanent teeth and its effect on the levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in gingival crevicular fluid.Methods:From January 2021 to August 2021, 72 young patients with permanent teeth exhibiting pulp necrosis and apical periodontitis who were treated at Haiyang People's Hospital were included in this study. These patients were subsequently divided into a study group ( n = 35) and a control group ( n = 37), depending on their respective treatment methods. The control group underwent conventional apical angioplasty, whereas the study group underwent pulp revascularization. A comparative analysis was conducted to assess the clinical efficacy of both treatments. Additionally, levels of VEGF and bFGF in gingival crevicular fluid were measured before and after surgery, and these values were compared between the two groups. Relevant clinical indicators and the incidence of adverse reactions were also compared between the study and control groups. Results:The overall response rate in the study group was 94.3% (33/35), which was significantly higher than 70.3% (26/37) in the control group ( χ2 = 7.01, P < 0.05). Prior to surgery, there were no notable differences in VEGF level, bFGF level, root length, or root canal thickness between the two groups (all P > 0.05). However, after surgery, VEGF level, bFGF level, root length, and root canal thickness in the study group were (43.25 ± 4.87) ng/L, (40.72 ± 4.83) ng/L, (8.95 ± 0.27) mm, and (3.08 ± 0.24) mm, respectively. These values were (39.90 ± 4.80) ng/L, (36.05 ± 4.66) ng/L, (8.55 ± 0.18) mm, and (2.90 ± 0.20) mm, respectively, in the control group. There were significant differences in VEGF level, bFGF level, root length, and root canal thickness between the two groups ( t = 2.96, 4.18, 5.67, 2.88, all P < 0.05). After surgery, the scores for apical inflammation, root development, and Visual Analogue Scale (VAS) in the study group were significantly higher than those in the control group ( t = 7.61, 4.83, 9.47, all P < 0.001). The incidence of adverse reactions in the study group was 2.9% (1/35), which was significantly lower than 21.6% (8/37) in the control group ( χ2 = 5.79, P < 0.05). Conclusion:Pulp revascularization exhibits superior curative effects compared with conventional apical angioplasty for the treatment of pulp necrosis and apical periodontitis in young permanent teeth. This treatment effectively alleviates pain, markedly improves tooth function, and has a low incidence of adverse reactions, highlighting its clinical value as a therapeutic option.

Research progress on SENP1/HIF-1α regulation of vascular differentiation of dental pulp stem cells / 中国医师杂志

Dental pulp stem cells (DPSC) are pluripotent stem cells with high differentiation potential isolated from dental pulp. Using DPSC for vascular regeneration may be a good option. Hypoxia inducible factor-1α (HIF-1α) is an upstream gene of vascular endothelial growth factor (VEGF), and the small ubiquitin like protease 1 (SENP1) can reverse the small ubiquitin like (SUMO) modification of HIF-1α. Through the regulation of SENP1/HIF-1α, good vascular regeneration characteristics have been demonstrated in many in vitro and in vivo experiments. The SENP1/HIF-1α signaling axis has varying degrees of promoting and inhibiting effects on many solid tumors. Although there is relatively little literature on the role of the SENP1/HIF-1α signaling axis in dental pulp stem cells, it can be determined that SENP1/HIF-1α plays an important role in the angiogenesis of dental pulp stem cells. This article will elucidate the SENP1/HIF-1α signaling pathway and its mechanism of promoting vascular differentiation of DPSC.

Can a dentin bonding agent prevent color change in regenerative endodontic procedures? An in vitro evaluation

Abstract This in vitro study aimed to determine the efficacy of dentin bonding agents in preventing color changes following Regenerative Endodontic Procedures. One hundred twenty bovine incisors were endodontically prepared and randomly assigned to a two main factors design: application of a dentin bonding agent (Scotchbond Adper, 3M ESPE, St Paul, MN, USA) in the pulp chamber (Group 1, n=60) versus no bonding intervention (Group 2, n=60), and five levels of intracanal medication (n=12/subgroup): Triple antibiotic paste (TAP), double antibiotic paste (DAB), calcium hydroxide (CH), modified triple antibiotic paste (TAPM), and Control (CTL). Color changes were measured over 28 days at multiple time points (1, 3, 7, 14, 21, and 28 days) using the CIEDE2000 formula to calculate the color difference (ΔE00) from baseline (T0). The ΔE00 quantifies the perceptible color difference between the initial and final tooth color, with lower values indicating less discoloration. The results were analyzed using repeated measures ANOVA-2 and post-hoc Holm-Sidak tests. The TAP subgroups, both with and without the bonding agent, exhibited the highest color variation. However, a pulp chamber seal with a bonding agent showed a protective effect against discoloration compared to no seal, even though complete prevention was not achieved. All groups demonstrated ΔE00 values beyond acceptable interpretation thresholds for clinical application, primarily driven by a reduction in lightness (L*) and a decrease in redness (a* value, shifting towards green). In conclusion, while the pulp chamber seal with a bonding agent mitigated TAP-induced discoloration, it did not eliminate it.

Resumo Este estudo in vitro avaliou adesivos dentinários na prevenção de alterações de cor após procedimentos endodônticos regenerativos. Cento e vinte incisivos bovinos foram preparados endodonticamente e aleatoriamente designados para um desenho com dois fatores principais: aplicação de agente adesivo (Scotchbond Adper, 3M ESPE, St Paul, MN, EUA) na câmara pulpar (Grupo 1, n=60) versus não intervenção adesiva (Grupo 2, n=60), e cinco níveis de medicação intracanal (n=12/subgrupo): pasta de triantibiótica (TAP), pasta diantibiótica (DAB), hidróxido de cálcio (CH), pasta triantibiótica modificada (TAPM) e Controle (CTL). Alterações cromáticas foram monitoradas por 28 dias em intervalos (1, 3, 7, 14, 21, e 28 dias), usando CIEDE2000 para calcular a diferença de cor (ΔE00) em relação a cor inicial. O ΔE00 quantifica a diferença entre a cor inicial e final do dente, com valores menores indicando menos descoloração. Os resultados foram analisados usando ANOVA-2 de medidas repetidas e teste posthoc de Holm-Sidak. Os grupos utilizando medicação TAP, com ou sem adesivo, possuíram as maiores variações cromática. Contudo, o uso do adesivo na câmara pulpar mostrou um efeito protetor contra descoloração, em comparação com a ausência do selamento adesivo, embora a prevenção completa não tenha sido alcançada. Todos os grupos demonstraram valores de ΔE00 além dos limiares aceitáveis para aplicação clínica, principalmente devido à redução na luminosidade (L*) e redução no vermelho (a*, deslocando-se em direção ao verde). Em conclusão, enquanto o selamento da câmara pulpar com um agente adesivo mitigou a descoloração induzida pelo TAP, mas não a eliminou completamente.

Identification and antimicrobial susceptibility profile of bacteria isolated from primary endodontic infections

Abstract This study aimed to identify and characterize the antimicrobial susceptibility profile of bacteria found in primary endodontic infections in the teeth of patients treated at the Dental Clinic of the University of Ribeirão Preto, São Paulo, Brazil. From September to December 2019, samples were obtained from 21 patients with primary endodontic infections. The collections were carried out in triplicate using paper cones placed close to the total length of the root canal. Bacterial isolation was performed in Brain Heart Infusion agar, Blood agar, and other selective culture media cultured at 37°C for up to 48 h under aerobiosis and microaerophilic conditions. The bacterial species were identified using the Vitek 2 automated system. The disk diffusion method on agar Müeller-Hinton was used to assess antimicrobial susceptibility with the recommended antimicrobials for each identified bacterial species. A total of 49 antibiotics were evaluated. Fifteen of the 21 samples collected showed bacterial growth, and 17 bacterial isolates were found. There were 10 different bacterial species identified: Enterococcus faecalis (four isolates), Streptococcus mitis/oralis (three isolates), Streptococcus anginosus (three isolates) being the most common, followed by Staphylococcus epidermidis, Enterococcus faecium, Streptococcus constellatus, Streptococcus alactolyticus, Enterobacter cloacae, Klebsiella variicola, and Providencia rettgeri (one isolate of each species). The analysis demonstrated significant susceptibility to most of the tested antibiotics. However, some Enterococcus isolates resisted the antibiotic's erythromycin, ciprofloxacin, and tetracycline. A Staphylococcus epidermidis isolate was characterized as multidrug-resistant. Five Streptococcus isolates were non-susceptible to all antibiotics tested.