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.

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.

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.

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.

Inhibition of lipopolysaccharide-induced NF-κB maintains osteogenesis of dental pulp and periodontal ligament stem cells

Abstract Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) can differentiate into osteoblasts, indicating that both are potential candidates for bone tissue engineering. Osteogenesis is influenced by many environmental factors, one of which is lipopolysaccharide (LPS). LPS-induced NF-κB activity affects the osteogenic potencies of different types of MSCs differently. This study evaluated the effect of LPS-induced NF-κB activity and its inhibition in DPSCs and PDLSCs. DPSCs and PDLSCs were cultured in an osteogenic medium, pretreated with/without NF-κB inhibitor Bay 11-7082, and treated with/without LPS. Alizarin red staining was performed to assess bone nodule formation, which was observed under an inverted light microscope. NF-κB and alkaline phosphatase (ALP) activities were measured to examine the effect of Bay 11-7082 pretreatment and LPS supplementation on osteogenic differentiation of DPSCs and PDLSCs. LPS significantly induced NF-κB activity (p = 0.000) and reduced ALP activity (p = 0.000), which inhibited bone nodule formation in DPSCs and PDLSCs. Bay 11-7082 inhibited LPS-induced NF-κB activity, and partially maintained ALP activity and osteogenic potency of LPS-supplemented DPSCs and PDLSCs. Thus, inhibition of LPS-induced NF-κB activity can maintain the osteogenic potency of DPSCs and PDLSCs.

Iron deficiency anemia as a risk factor for pulp disease in children from the central Peruvian jungle: a case‒control study

Abstract Aim To investigate iron-deficiency anemia as a risk factor for dental pulp disease in children from the central Peruvian jungle. Methodology A case-control study was carried out with 270 children, of which 90 referred to cases and 180, to controls. Patients with pulp disease were diagnosed according to the criteria of the Association of Endodontists and the American Board of Endodontics. A specific questionnaire was used to assess ferrous sulfate consumption, maternal education level, maternal age, occupation, and household income. Data were analyzed using Pearson's correlation coefficient and a binary logistic regression. Results Iron deficiency anemia offers a risk factor for pulp disease in children (OR 7.44, IC 95% 4.0-13.8). According to multivariate analysis using binary logistic regression, ferrous sulfate consumption (OR 13.8, IC 95% 5.6.33.9), maternal education level (OR 2.4, IC 95% 1.1-5.3), maternal age (OR 7.5, IC 95% 2.9-19.4), household income (OR 4.0, IC 95% 1.6-9.6), and caries (OR 10.7, IC 95% 4.5-25.7) configured independent factors that were statistically associated with pulp disease. Conclusion Iron deficiency anemia, ferrous sulfate consumption, maternal education level, maternal age, household income, and dental caries were positively associated with pulp disease in children

Effect of hydrofluoric acid concentration and aging on the bond strength ceramics to a resin cement

Abstract This study evaluated the influence of hydrofluoric acid (HF) concentration and thermal cycling on the microshear bond strength (µSBS) of a resin luting agent to IPS e.max® CAD and Rosetta® SM. Ceramic specimens (12.0 x 14.0 x 1.5mm) were randomized into 8 groups (n=10) according to HF concentration, commercial brand, and aging. Immediately after polishing, and etching, all specimens were silanized and a layer of adhesive was applied. A PVS mold of 3 mm thickness and 10mm diameter with (four) 1.0mm holes was fabricated, placed on each specimen, and then filled with a resin luting agent. Half of the specimens were subjected to the µSBS test using an Instron at a speed of 1.0 mm/min, following a 24-hour storage in deionized water at 37ºC. The remaining specimens were subjected to thermal cycling (5ºC-55ºC, 30 seconds per bath) and µSBS. The data were evaluated utilizing a three-way ANOVA and Tukey's post-hoc test (α=0.05). Significant differences were found for HF concentration and aging (p<0.0001). No significant difference in µSBS was found for commercial brands (p=0.085). The interaction between brand and HF concentration (p=0.358), brand and aging (p=0.135), and HF concentration and aging (p=0.138) were not statistically significant. The triple interaction among these factors was not statistically significant (p=0.610). In conclusion, the bond strength is affected by the HF concentration. No statistical difference was observed between the two ceramics. Thermal cycling significantly reduced µSBS.

Resumo Este estudo avaliou a influência da concentração do ácido fluorídrico (AF) e da ciclagem térmica na resistência de união ao microcisalhamento (RUµC) de um cimento resinoso para IPS e.max® CAD e Rosetta® SM. Espécimes cerâmicos (12,0 x 14,0 x 1,5mm) foram divididos em 8 grupos (n=10) de acordo com concentração do HF, marca comercial e envelhecimento. Imediatamente após o polimento e condicionamento ácido, todos os espécimes foram silanizados e uma camada de adesivo foi aplicada. Um molde PVS de 3 mm de espessura e 10 mm de diâmetro com (quatro) orifícios de 1,0 mm foi confeccionado, colocado em cada espécime e preenchido com o cimento resinoso. Metade dos espécimes foi submetida ao teste RUµC na Instron a velocidade de 1,0 mm/min, após 24 horas de armazenamento em água deionizada a 37ºC. Os espécimes restantes foram submetidos a ciclagem térmica (5ºC-55ºC, 30 segundos por banho) e a RUµC. Os dados foram avaliados por ANOVA de três fatores e ao teste post-hoc de Tukey (α=0,05). Diferenças significativas foram encontradas para concentração de HF e envelhecimento (p<0,0001). Nenhuma diferença significativa na RUµC foi encontrada para cada marca comercial (p=0,085). A interação entre marca comercial e a concentração do HF (p=0,358), marca comercial e envelhecimento (p=0,135) e concentração do HF e envelhecimento (p=0,138) não foram estatisticamente significativas. A tripla interação entre esses fatores não foi estatisticamente significativa (p=0,610). Concluindo, a resistência de união é afetada pela concentração de HF. Não foi observada diferença estatística entre as duas cerâmicas. A ciclagem térmica reduziu significativamente a resistência de união ao microcisalhamento.

Cytotoxic effects on human dental pulp stem Cells after exposure to adhesive bonding agents

Abstract Studies regarding cytotoxic effects attributed to the use of adhesive bonding agents on pulp tissue are not conclusive. To point out whether these materials are safe for clinical use, in vivo exposure of dental pulp to adhesive bonding agents was simulated using an experimental setup in which Human Dental Pulp Stem Cells (hDPSC) are exposed to the action of two kinds of adhesives: self-etching adhesives and two-step bonding agents through a dentine barrier. Cytotoxic effects on these cells were evaluated by MTT assay protocol and fluorescence microscopy, and their results were contrasted to those obtained through Raman spectra taken on single hDPSCs. Overall, no significant cytotoxic effects were observed by combining all the techniques, and cell viability close to 90% was achieved for a dentine barrier of at least 1 mm thick. Moreover, Raman spectroscopy was able to detect structural DNA damage in some dental pulp cells when exposed to two-step bonding agents, suggesting that this technique could be considered a complementary tool with the potential to evaluate cell toxicity beyond cell viability.

Resumo Os estudos sobre os efeitos citotóxicos atribuídos ao uso de agentes de união adesivo no tecido pulpar não são conclusivos. Para determinar se esses materiais são seguros para uso clínico, a exposição in vivo da polpa dentária a agentes de união adesiva foi simulada por meio de uma configuração experimental na qual as células-tronco da polpa dentária humana (hDPSC) são expostas à ação de dois tipos de adesivos: adesivos autocondicionantes e agentes de união de duas etapas por meio de uma barreira de dentina. Os efeitos citotóxicos nessas células foram avaliados pelo protocolo de ensaio MTT e microscopia de fluorescência, e seus resultados foram contrastados com os obtidos por meio de espectros Raman obtidos em hDPSCs individuais. De modo geral, não foram observados efeitos citotóxicos significativos com a combinação de todas as técnicas, e a viabilidade celular próxima a 90% foi obtida para uma barreira de dentina de pelo menos 1 mm de espessura. Além disso, a espectroscopia Raman foi capaz de detectar danos estruturais ao DNA em algumas células da polpa dentária quando expostas a agentes de colagem de duas etapas, sugerindo que essa técnica poderia ser considerada uma ferramenta complementar com potencial para avaliar a toxicidade celular além da viabilidade celular.

Prevalence of species of yellow, purple and green microbial complexes in endo-perio lesions: a systematic review

Abstract This review aimed to determine the prevalence of species of yellow, purple and green microbial complexes in root canals (RC) and periodontal pockets (PP) of teeth with endodontic-periodontal lesions. For this purpose, two reviewers searched the literature up to January 2022. Studies reporting the prevalence of species of the yellow, purple and green microbial complexes in teeth diagnosed with endodontic-periodontal lesions were included. The risk of bias of the included studies was assessed using the 14 criteria from the NIH Quality Assessment Tool. Of 1,611 references identified in the initial search, only four studies were eligible and included in the qualitative analysis. The profile and prevalence rates of bacterial species in RC and PP varied among the included studies: levels of Agregatibacter actinomycetemcomitans (12% RC, 58% PP), Capnocytophaga granulosa (10% RC, 35% PP), Capnocytophaga sputigena (15-70% RC, 0-30% PP), Streptococcus mitis (30% RC, 35% PP), Streptococcus sanguinis (30% RC, 35% PP), and Veillonella parvula (70% RC, 50% PP) were identified. The high methodological heterogeneity prevented grouping and quantitative analysis of data. The risk of bias was considered 'moderate' for all studies. The included studies identified the presence of seven bacterial species belonging to the yellow, purple, and green microbial complexes in RC and PP, but with different prevalence rates. Future clinical studies are encouraged to investigate the presence and role of these species in the occurrence and development of endodontic-periodontal lesions.

Influence of sealer and supplementary approach on filling material removal during endodontic retreatment

Abstract Both root canal sealer-based and supplementary protocols may influence removal of filling material during endodontic retreatment. Mesial root canals of extracted mandibular molars were prepared using HyFlex EDM 25/.08, and filled with a calcium silicate sealer (Bio-C Sealer), or an epoxy resin (AH Plus), using the single cone technique (n = 12). Retreatment was performed using ProDesign Logic (PDL) RT and PDL 35/.05. The specimens were randomly divided into two experimental groups (n = 12), and the sealers were distributed similarly. A supplementary protocol was performed with PDL 50/.01 or XP-endo Finisher. Root canal transportation and volume, in addition to the remaining filling material percentage were evaluated using high-resolution (5 µm voxel size) micro-CT. Statistical analysis was performed using t-tests (α = 0.05). Root canals filled with AH Plus presented high residual filling material (p < 0.05). Both protocols decreased residual volume of filling material in the apical third (p < 0.05). PDL 50/.01 increased the apical root canal volume (p < 0.05). No difference was observed between the systems regarding canal transportation (p > 0.05). In conclusion, AH Plus is more difficult to remove from the apical third than Bio-C Sealer. PDL 50/.01 and XP-endo Finisher enabled greater removal of filling materials in the apical third, in the retreatment of curved root canals, without promoting apical transport.

LncRNA XIST facilitates the odontogenic differentiation of dental pulp stem cells via the FUS/ZBTB16

Abstract Objective This study aims to explore the regulatory mechanism of long noncoding RNA X inactive specific transcript (lncRNA XIST) in the odontogenic differentiation of human dental pulp stem cells (hDPSCs). hDPSCs were obtained from freshly extracted third molars and identified by flow cytometry. Methodology Odontogenic differentiation was induced in mineralized culture medium, and hDPSCs were infected with shRNA lentivirus targeting XIST or fused in sarcoma (FUS), followed by detection of alkaline phoshpatase (ALP) activity, alizarin red staining of mineralized nodules, Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) quantification of XIST expression, and Western blot analysis of FUS, ZBTB16, and odontogenic differentiation markers (DSPP and DMP1). IF-FISH was performed to detect the cellular localization of XIST and FUS. RIP assay validated the XIST and FUS binding. ZBTB16 mRNA stability was tested after actinomycin D treatment. hDPSCs were infected with oe-ZBTB16 lentivirus and further treated with sh-XIST for a combined experiment. Results LncRNA XIST was highly expressed in hDPSCs with odontogenic differentiation. Downregulation of XIST or FUS weakened the ALP activity of hDPSCs, reduced mineralized nodules, diminished DSPP and DMP1 expressions. XIST binds to FUS to stabilize ZBTB16 mRNA and promote ZBTB16 expression. ZBTB16 overexpression partially reversed the inhibitory effect of XIST silencing on odontogenic differentiation of hDPSCs. Conclusion In conclusion, XIST stabilizes ZBTB16 mRNA and promotes ZBTB16 expression by binding to FUS, thereby facilitating the odontogenic differentiation of hDPSCs.

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.

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.

The applications of the plasma matrix in the treatments of dental pulp and periapical diseases / 口腔疾病防治

@#The plasma matrix is a kind of autologous blood conduct. It has been widely used in maxillofacial tissue regeneration, skin cosmetology and some other fields. Recently, to preserve the dental pulp as well as the teeth, pulp regeneration therapy and apical surgery have become increasingly important as well as the applications of bioactive materials. As a kind of autologous bioactive material, the plasma matrix has some natural advantages as it is easy to obtain and malleable. The plasma matrix can be used in the following cases: ①pulp revascularization of young permanent teeth with open apical foramina that cannot stimulate apical bleeding; ② apical barrier surgery with bone defects and large area perforation repair with bone defects or root sidewall repair surgery; ③ apical surgeries of teeth with large area of apical lesions, with or without periodontal diseases. The plasma matrix is a product derived from our blood, and there are no obvious contraindications for its use. Several systematic reviews have shown that the plasma matrix can effectively promote the regenerative repair of dental pulp in patients with periapical diseases. However, the applications of plasma matrix are different because its characteristics are affected by different preparation methods. In addition, there is still a lack of long-term clinical researches on the plasma matrix, and the histological evidences are difficult to obtain, so a large number of in vitro and in vivo experimental studies are still needed. This article will describe the applications of different kinds of plasma matrix for dental pulp regeneration and bone tissue regeneration in apical surgeries to provide references for clinicians in indication selection and prognosis evaluation.

Research progress on direct pulp capping of primary teeth / 口腔疾病防治

@#The timely treatment of dental caries and pulp disease in primary teeth holds significant importance for maintaining children's oral health. Direct pulp capping (DPC) is a vital pulp treatment that involves covering the exposed pulp with bioactive materials to promote dentin bridge formation. DPC is commonly used in primary teeth with vital pulp and mechanical pulp exposure not exceeding 1 mm. DPC offers advantages such as minimal invasiveness, comfort, simplicity of operation and short chair-side time, making it suitable for pediatric dental clinical practice. Early studies suggested negative treatment outcomes for DPC in primary teeth with carious pulp exposure. Over the years, there have been advancements in materials and technology demonstrating positive outcomes in the clinical research of primary teeth with deep caries. However, due to the limited quality of related studies, DPC has not been widely recommended for the treatment of primary teeth with carious pulp exposure, and its widespread use needs further support by more high-quality evidence-based medical research. The success rate of DPC in primary teeth is influenced by factors including pulp status, clinical operations (such as isolation and caries removal), pulp capping material, cavity type, tooth position, coronal sealing, and dental fear. In clinical operation, dentists should accurately assess pulp status and minimize bacterial contamination. Mineral trioxide aggregate (MTA) is a DPC agent with relatively sufficient evidence and good therapeutic effects, and the crown should be tightly sealed after pulp capping. Additionally, the effects of novel biocompatible materials such as iRoot BP Plus used in DPC of primary teeth, and the influence of other factors like hemostatic methods on the prognosis of affected teeth, need further exploration.

Comparison of the efficacy of two bioceramic materials in vital pulp preservation of mature permanent teeth with exposed pulp of caries origin / 预防医学

Objective@#To compare the efficacy of two bioceramic materials, iRoot BP Plus and mineral trioxide aggregate (MTA) in the preservation of vital pulp of mature permanent teeth with exposed pulp of caries origin, so as to provide insights into appropriate selection of pulp capping agents in clinical process.@*Methods@#Vital pulp therapy were performed on 120 mature permanent teeth with carious exposure at the Department of Stomatology of Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical University. The teeth were randomly divided into two groups which were treated respectively by iRoot BP Plus (iRoot group) and MTA (MTA group). The clinical efficacy was evaluated by clinical examinations and imaging examinations.@*Results@#There were 60 cases in iRoot group, including 23 males and 37 females, 27 cases affected premolars and 33 cases affected molars, and 8 cases of Class I and 52 cases of Class II cavity type, with a median age of 41 (interquartile range, 12) years. There were 60 cases in MTA group, including 29 males and 31 females, 21 cases affected premolars and 39 cases affected molars, and 10 cases of Class I and 50 cases of Class II cavity type, with a median age of 39 (interquartile range, 14) years. There were no significant differences in gender, age, affected tooth location and cavity type between the two groups (P>0.05). The success rate of iRoot group at 12 months was 91.67% while the MTA group was 88.33%, and the pulp infection rate of iRoot group at 12 months was 8.33% while the MTA group was 11.67%. There were no significant differences in success rate and pulp infection rate between the two groups (P>0.05). The rate of crown discoloration in MTA group was 61.67%, while there was no discoloration in iRoot group.@*Conclusions@#During 12 months, iRoot BP Plus and MTA can both achieve great effects in the treatment of mature permanent teeth with carious pulp exposure, but there is a problem of tooth discoloration after pulp covering using MTA. The long-term clinical effects of the two materials need to be further studied.