Increase Toll-like receptors 2 and 4 in apical periodontitis of rats with chronic liver disease.

The aim of this study was to evaluate the influence of liver fibrosis (LF) on the expression of Toll-like receptors (TLR) 2 and 4 in apical periodontitis (AP) in Wistar rats. Forty Wistar rats were allocated in the following groups (n = 10): C-control; AP-apical periodontitis; LF-liver fibrosis; AP + LF-rats with AP and LF. LF and AP were induced by established methodologies. Histological, bacteriological, and immunohistochemical analyses were performed according to pre-established scores. For comparisons between AP and AP + LF groups, the Mann-Whitney test was used (P < .05). The livers of the LF and AP + LF groups showed generalized portal inflammatory infiltrate and collagen fibers confirming the presence of LF. Histopathological analysis in the maxilla of the AP + LF group showed areas of necrosis comprising the entire dental pulp and periapical tissue surrounded by a more intense inflammatory infiltrate than observed in the AP group (P = 0.032). A significant number of specimens in the AP + LF group showed microorganisms beyond the apical foramen adhered to the extraradicular biofilm, demonstrating greater invasion compared to the AP group (P = .008). Immunohistochemical analysis showed a large number of cells immunoreactive for TLR2 and TLR4 in the AP + LF group, compared to the AP group (P < 0.05). Liver fibrosis favors the inflammation and contamination of microorganisms in apical periodontitis and triggers the expression of TLR2 and TLR4, modulating innate immunity response in periapical lesions.

Evolution of endodontic medicine: a critical narrative review of the interrelationship between endodontics and systemic pathological conditions.

Endodontics has gained emphasis in the scientific community in recent years due to the increase in clinical and in animal models studies focused on endodontic medicine, which aims to evaluate the interrelationship between systemic and periapical tissues pathological conditions. These studies have shown that systemic changes can boost the pathogenesis of endodontic infection, favoring its development and progression. A contrary relationship is reported in numerous studies that affirm the potential of endodontic infection to trigger systemic damage and may lead to the worsening of pre-existing pathologies. Recently, the potential of filling materials to develop systemic changes such as neurological alterations had been evaluated, also showing that systemic diseases can negatively influence tissue responses to filling materials after endodontic treatment. Despite advances in endodontic medicine studies, there are still gaps in knowledge on the mechanisms of interactions between apical periodontitis (AP) and systemic diseases and much research to be done. In this sense, this critical narrative literature review aimed to show the evolution of studies in endodontic medicine to help the endodontist to know the role of systemic diseases in the pathogenesis of AP and the possible interference in the repair of periapical tissues after endodontic treatment, as well as to evidence the systemic complications that can be triggered or aggravated in the presence of endodontic infection.

Viruses in pulp and periapical inflammation: a review.

The presence of viruses in endodontic disease has been studied in the last decade. Their presence is associated with periapical radiolucency and with clinical findings, such as pain. The aim of this review is to analyze the scientific evidence currently published about viruses in pulp and periapical inflammation, and its possible clinical implications. A literature review was carried out using the Medline/Pubmed database. The search was performed, in English and Spanish, using the following keyword combinations: virus AND endodontic; virus AND periapical; virus AND pulpitis; herpesvirus AND periapical; papillomavirus AND periapical. We subsequently selected the most relevant studies, which complied with the search criterion. A total of 21 articles were included, of which 18 detected the present of viruses in the samples. In 3 of the studies, viral presence was not found in the samples studied. The Epstein-Barr virus was found in about 41 % of cases compared to controls, in which it was present in about 2 %. The main association between viruses and endodontic pathosis is between Cytomegalovirus and Epstein-Barr virus; these are found in 114 of the 406 samples of different endodontic pathosis. Some evidence supports that the Epstein-Barr virus is present in a significant number of endodontic diseases, without exact knowledge of their action in these diseases.

Radiolucent periapical lesions and bone mineral density in post-menopausal women.

PURPOSE: To investigate the relationship between radiolucent periapical lesions and bone mineral density in post-menopausal women. MATERIAL AND METHODS: Seventy-five post-menopausal women were recruited for the study. Bone mineral density was measured using dual-energy X-ray absorptiometry. Three groups were established: healthy bone group, osteopenic group and osteoporotic group. Periapical radiolucencies were diagnosed on the basis of examination of digital panoramic radiographs. Statistical analysis was carried out using anova and chi-squared tests, and logistic regression analysis. RESULTS: In both the osteopenic and osteoporotic groups, 25% of women showed at least one periapical radiolucency, whereas this was only 7.4% in the healthy bone group (odds ratio = 4.2; p = 0.061). After multivariate logistic regression analysis adjusting for covariates (age, number of teeth, number of root-filled teeth and number of teeth with coronal restorations), a marginally significant association was evident between bone mineral density and the presence of periapical radiolucencies (odds ratio = 1.9; CI 95% = 1.0-3.8; p = 0.050). CONCLUSIONS: After adjusting for covariates, low bone mineral density is marginally associated with a higher frequency of radiolucent periapical lesions.

Protocol for oral implant rehabilitation in a hemophilic HIV-positive patient with type C hepatitis.

CASE REPORT: A 46-year-old man with severe hemophilia A, stage A2 HIV infection and chronic hepatitis C genotype 1A, for whom the treatment plan included implant-supported prostheses in 2 mandibular edentulous sections. The protocol followed included factor VIII replacement concentrate and oral antifibrinolytic therapy. The right mandibular section was fitted with 3 Straumann implants (Ø 4.1 mm, length 10 mm), and the left mandibular section received 2 implants of the same characteristics. The patient showed no postoperative complications. After implant placement, the patient attended scheduled review appointments. After a 3-month period of osseointegration, the prosthesis was fitted. CONCLUSIONS: Although, in this case, the treatment proved successful 2 years postrehabilitation and the protocol used seems safe and effective, long-term prospective studies are needed to evaluate the implant success rate in these patients.

Influence of state anxiety and trate anxiety in postoperative in oral surgery.

INTRODUCTION: The aim of this article was to study the influence of anxiety (both state and trait) in postoperative recovery after extraction of third molar together, to establish the role of each of the aspects of anxiety in the results you obtained in an independent and complementary way. MATERIAL AND METHOD: We performed a prospective study of a consecutive series of 88 patients who underwent lower third molar extractions. Before being provided with any information about the operation, patients were asked to complete the Spielberger State-Trait Anxiety Inventory- Trait and State. We have evaluated postoperative swelling and pain, patients completed a 10-point visual analog scale (VAS) at home each day (at approximately the same time of day as the operation) until day 8 after surgery, when the sutures were removed. RESULTS: Regarding postoperative variables between positive and negative trait anxiety groups, consumption of analgesic drugs was higher in positive trait anxiety group in a statistically significant way, while these differences were detected only on specific occasions regarding pain and swelling. DISCUSSION: In the present study, anxiety was taken into account and showed a significant effect in explaining postoperative pain and taking analgesics.

Patients' Opinions on Antibiotics in the Treatment of Dental Infections: A Cross-Sectional Survey.

Background: The aim of this study was to evaluate patients' knowledge and perceptions of the use of systemic antibiotics in the treatment of endodontic infections and to determine the possible contribution of patients to the development of bacterial resistance. Methods: A total of 550 patients were asked to respond to a survey on the perception of systemic antibiotic use in the treatment of endodontic infections and antibiotic resistance during January 2022 and March 2023. A bivariate and multivariate analysis was performed to determine possible correlates in the population regarding antibiotic use in the endodontic world. Results: A total of 514 patients were included in the study, 65.9% of whom were women. While 34.6% of the population studied thought that it was always necessary to take antibiotics prior to endodontics, 49.4% considered that they were necessary after endodontics, regardless of the clinical symptoms. The prevalence of self-medication was 17.3%, and women self-medicate more than men, with significant differences (p < 0.05), although they have a greater knowledge of antibiotic resistance than men (p < 0.05). Forty-four percent of the population expected to take antibiotics when faced with dental pain, mainly women (p < 0.05). Conclusions: The general population is contributing to the serious problem of bacterial resistance. It is necessary to promote educational strategies focused on the correct use of antibiotics in the community. The worst results were found mainly in the population with a low level of education. The level of education was the variable that most influenced the knowledge and attitudes of the population, followed by the sex of the participants.

Confocal microscopy: a valid approach to evaluate the three-dimensional characteristics of root-end cavities.

OBJECTIVE: To analyze, using confocal microscope, the three-dimensional characteristics of the root-end cavity preparations completed in root apices of extracted teeth determining their area, perimeter, circularity and cavo-surface angle. STUDY DESIGN: Thirty-two single-rooted extracted teeth underwent endodontic treatment and apical resection. Root-end cavities were prepared according to 4 protocols, as follows: Group 1, stainless steel ultrasonic tips (SST) at 33 KHz power; Group 2, SST at 30 KHz power; Group 3, diamond-coated ultrasonic tips (DCT) at 30 KHz power; and Group 4, DCT at 33 KHz power. Finally, root-end cavity was evaluated using a confocal microscope, recording its area, perimeter, circularity and cavo-surface angle. RESULTS: The largest cavity perimeter was found in the Group 2 (4.8 ± 1.6 mm) (p > 0.05). Root-end cavities performed using SST showed larger areas than those performed with DCT (p = 0.03). The power of vibration or the tip type did not show correlation with the perimeter, circularity and cavo-surface angle of the root-end cavity (p > 0.05). CONCLUSIONS: Confocal microscopy is a useful approach to study the three-dimensional characteristics of the root-end cavity.

A comparison of the dental status and treatment needs of older adults with and without chronic mental illness in Sevilla, Spain.

OBJECTIVES: To study the dental status and treatment needs of institutionalized older adults with chronic mental illness compared to a non-psychiatric control sample. STUDY DESIGN: The sample size was 100, in which 50 were psychogeriatric patients (study group; SG) classified according to DSM-IV, with a mean age of 69.6 ± 6.7 years, and 50 non-psychiatric patients (control group; CG), with a mean age of 68.3 ± 6.9 years. Clinical oral health examinations were conducted and caries were recorded clinically using the Decayed, Missing and Filled Teeth Index (DMFT). Results were analyzed statistically using the Student's t-test or analysis of variance. RESULTS: Caries prevalence was 58% and 62% in SG and CG, respectively. DMFT index was 28.3 ± 6.6 in SG and 21.4 ± 6.07 in CG (p < 0.01). Mean number of decayed teeth was higher in SG (3.1) compared to CG (1.8) (p=0.047). Mean number of missing teeth were 25.2 and 16.4 in SG and CG respectively (p<0.05). DMFT scores were higher in SG in all the age groups (p < 0.01). Mean number of teeth per person needing treatment was 3.4 in SG and 1.9 in CG (p= 0.037). The need for restorative dental care was significantly lower in the SG (0.8 teeth per person) than in the CG (1.7 teeth per person) (p = 0.043). CONCLUSIONS: Institutionalized psychiatric patients have significantly worse dental status and more dental treatment needs than non-psychiatric patients.

The Role of Apical Periodontitis Disease in the Development of Bisphosphonate-Related Osteonecrosis of the Jaw: An Animal Study.

BACKGROUND: Microorganisms and their by-products are responsible for establishing pulpal and periapical diseases. Healing is compromised in patients under bisphosphonate therapy, and the presence of periapical infections can potentially lead to the development of medication-related osteonecrosis of the jaw (MRONJ). This work aimed to evaluate if bisphosphonate therapy is a risk factor for MRONJ development in the presence of periapical lesions. METHODS: Two groups of 10 female Wistar rats were used. The experimental group received zoledronate (0.1 mg/kg) intraperitoneally, and the control received a saline solution, three times a week for three weeks. One week after the last injection, apical periodontitis was induced through pulpal exposure in the mandibular first molars. Twenty-one days later, the animals were intravenously injected with 99mTc-HMDP, and the radioactivity uptake by mandibular specimens was counted. In addition, sample radiographs and a histological examination were performed. RESULTS: The bone loss was higher in the control group when compared to the experimental group (p = 0.027). 99mTc-HMDP uptake in the control was reduced compared with the experimental group, although without statistical significance. CONCLUSIONS: In the presence of zoledronate therapy, apical periodontitis does not increase the risk of MRONJ development, and periapical lesions have lower bone resorption when compared to the control group.

Suture needles in oral surgery: alterations depending on the type and number of sutures.

This study examined whether the number and type of sutures used in oral surgery influence two ad hoc variables (incision plane and displaced area), which are two variables related to whether the suture needle is suitable for the task. Seventy-five TB-15 needles were studied, which were used to suture between zero and three mucosa and/subperiosteal sutures, producing 15 groups with 5 needles in each one. The incision plane and displaced area were measured for each group, which are two variables related to how the needle has worn and altered. Statistical treatment was conducted using the Kruskal-Wallis H test to compare multiple values and the Mann-Whitney U test to compare pairs. A multi-stage regression model was applied with the aim of predicting the changes in the dependent variables based on the number and type of sutures performed. The incision plane ranged from 126.67 to 346.24 µm among the different groups. The displaced area was measured as being between 14 524.83 µm² and 128 311.91 µm². The best predictive model for the incision plane obtained a coefficient of determination (R2) of 0.149, while it reached 0.249 for the displaced area. Subperiosteal sutures held more weighting among the variables studied. Mucosal sutures did not seem to greatly affect needle wear. Observations reported in this paper indicate that the needle should be changed after having performed two subperiosteal sutures, given the wear and change to the incision plane that is produced, which causes the needle's cutting ability to reduce.

Computer-aided system for morphometric mandibular index computation. (Using dental panoramic radiographs).

OBJECTIVE: We propose and validate a computer-aided system to measure three different mandibular indexes: cortical width, panoramic mandibular index and, mandibular alveolar bone resorption index. STUDY DESIGN: Repeatability and reproducibility of the measurements are analyzed and compared to the manual estimation of the same indexes. RESULTS: The proposed computerized system exhibits superior repeatability and reproducibility rates compared to standard manual methods. Moreover, the time required to perform the measurements using the proposed method is negligible compared to perform the measurements manually. CONCLUSIONS: We have proposed a very user friendly computerized method to measure three different morphometric mandibular indexes. From the results we can conclude that the system provides a practical manner to perform these measurements. It does not require an expert examiner and does not take more than 16 seconds per analysis. Thus, it may be suitable to diagnose osteoporosis using dental panoramic radiographs.

Evaluation of apical preparations performed with ultrasonic diamond and stainless steel tips at different intensities using a scanning electron microscope in endodontic surgery.

OBJECTIVE: The objective of our study is to analyse (with the help of scanning electron microscopes) the quality of the dental root surface and the appearance of dental cracks after performing apical preparations using two different types of ultrasonic tips. STUDY DESIGN: We used 32 single-rooted teeth that underwent a root canal and apical resection. Afterwards, the teeth were divided into 4 groups of 8 teeth each, with preparations of the apical cavities in the following manner: Group 1: stainless steel ultrasonic tip at 33 KHz. Group 2: stainless steel ultrasonic tip at 30 KHz. Group 3: diamond ultrasonic tip at 30 KHz. Group 4: diamond ultrasonic tip at 33 KHz. The quality of the root surface and the presence of cracks were evaluated by one single observer using a scanning electron microscope. RESULTS: All of the teeth in our study had cracks after the apical preparations. The mean number of cracks per tooth ranged between 6. ± 1.9 (group 1) and 3.5 ± 2.4 (group 4), with a significantly higher number found in the groups that used stainless steel tips (P=.03). The types of cracks produced involved: 8 complete cracks (4.5%), 167 incomplete cracks (94.4%), and 2 intradentinal cracks (1.1%), with no significant differences observed between the different frequencies used for each group. CONCLUSIONS: Stainless steel ultrasonic tips provoked a larger number of cracks than diamond tips. The frequency of vibration used did not have any effect on the number of cracks found.

Influence of root canal instrumentation and obturation techniques on intra-operative pain during endodontic therapy.

OBJECTIVE: To analyse the influence of root canal instrumentation and obturation techniques on intra-operative pain experienced by patients during endodontic therapy. METHOD AND MATERIALS: A descriptive cross-sectional study was carried out in Ponferrada and Sevilla, Spain, including 80 patients (46 men and 34 women), with ages ranged from 10 to 74 years, randomly recruited. Patient gender and age, affected tooth, pulpal diagnosis, periapical status, previous NSAID or antibiotic (AB) treatment, and root canal instrumentation and obturation techniques were recorded. After root canal treatment (RCT), patients completed a 10-cm visual analogue scale (VAS) that ranked the level of pain. Results were analysed statistically using the Chi-square and ANOVA tests and logistic regression analysis. RESULTS: The mean pain level during root canal treatment was 2.9±3.0 (median=2) in a VAS between 0 and 10. Forty percent of patients experienced no pain. Gender, age, arch, previous NSAIDs or AB treatment and anaesthetic type did not influence significantly the pain level (p>0.05). Pain during root canal treatment was significantly greater in molar teeth (OR=10.1; 95% C.I.=1.6-63.5; p=0.013). Root canal instrumentation and obturation techniques did not affect significantly patients' pain during root canal treatment (p>0.05). CONCLUSION: Patients feel more pain when RCT is carried out on molar teeth. The root canal instrumentation and obturation techniques do not affect significantly the patients' pain during RCT.

A Microstructure Insight of MTA Repair HP of Rapid Setting Capacity and Bioactive Response.

Mineral trioxide aggregate (MTA) is considered a bioactive endodontic material, which promotes natural mineralization at the material-tooth tissue interface. MTA Repair HP stands out because of the short setting time and the quick and effective bioactive response in vitro. The bioactivity, depens on material composition and microstructure. This work is devoted to analyze MTA Repair HP microstructural features, of both the powder precursor and set material, to get insights into the material physicochemical parameters-functionality performance relationships. Transmission electron microscopy (TEM), and field emission gun scanning electron microscopy (FEG-SEM) coupled with energy-dispersive X-ray (EDX) analyses were performed. X-ray diffraction (XRD) measurements were carried out at different times to investigate setting process. Bioactivity evaluation in vitro was carried out by soaking the processed cement disk in simulated body fluid (SBF). The presented results point out those MTA Repair HP precursor material characteristics of tricalcium silicate particles of nanometric size and high aspect ratio, which provide an elevated surface area and maximized components dispersion of calcium silicate and very reactive calcium aluminate. The MTA Repair HP precursor powder nanostructure and formulation, allows a hydration process comprising silicate hydrate structures, which are very effective to achieve both fast setting and efficient bioactive response.

Apical Periodontitis and Diabetes Mellitus Type 2: A Systematic Review and Meta-Analysis.

OBJECTIVE: Investigate if there is an association between apical periodontitis and diabetes mellitus. MATERIAL AND METHODS: A bibliographic search was performed on Medline/PubMed, Scopus and Cochrane databases using the keywords apical periodontitis and diabetes mellitus. Published papers written in English and performed on animals or humans were included. Meta-analysis was performed using the OpenMeta (analyst) tool for the statistical analysis. The variables analyzed were the prevalence of Apical Periodontitis (AP) among teeth and patients with Diabetes Mellitus (DM). RESULTS: Of the total studies found, only 21 met the inclusion criteria. Ten clinical studies on animals, ten studies on humans and a systematic review were included. Meta-analysis shows that the prevalence of teeth with apical periodontitis among patients with diabetes mellitus has an odds ratio of 1.166 corresponding to 507 teeth with AP + DM and 534 teeth with AP without DM. The prevalence of patients with AP and DM shows an odds ratio of 1.552 where 91 patients had AP + DM and 582 patients AP without DM. CONCLUSION: Scientific evidence suggests that there could be a common physiopathological factor between apical periodontitis and diabetes mellitus but more prospective studies are needed to investigate the association between these two diseases.

Relationship between Apical Periodontitis and Metabolic Syndrome and Cardiovascular Events: A Cross-Sectional Study.

AIM: Both apical periodontitis (AP) and metabolic syndrome (MetS) are associated with atherosclerotic cardiovascular disease (ACVD), the main cause of cardiovascular events. The aim of this study was to investigate the prevalence of AP and the oral inflammatory burden in control subjects and patients suffering cardiovascular events, analyzing the possible association between AP and the oral inflammatory burden with MetS. MATERIALS AND METHODS: Using a cross-sectional design, 83 patients suffering a cardiovascular event were recruited in the study group (SG), and 48 patients without cardiovascular events were included in the control group (CG). Periapical index (PAI) was used to diagnose AP, and total dental index (TDI) was used to assess the total oral inflammatory burden. Diagnosis of MetS was made by meeting three or more American Heart Association Scientific Statement components. RESULTS: In the multivariate logistic regression analysis, the number of teeth with AP (OR = 2.3; 95% C.I. = 1.3-4.3; p = 0.006) and TDI scores (OR = 1.5; 95% C.I. = 1.2-1.9; p = 0.001), significantly correlated with cardiovascular events. MetS was strongly associated (OR = 18.0; 95% C.I. = 6.5-49.7; p = 0000) with cardiovascular events. Higher TDI scores were significantly associated with MetS (OR = 1.3; 95% C.I. = 1.1-1.6; p = 0.003. Neither the number of root-filled teeth (RFT) (OR = 0.9; 95% C.I. = 0.6-1.3; p = 0.61) nor the number of teeth with apical periodontitis (OR = 1.1; 95% C.I. = 0.8-1.7; p = 0.49) were associated with MetS. CONCLUSIONS: Apical periodontitis is significantly associated with cardiovascular events. Total oral inflammatory burden assessed by TDI, but not AP alone, is associated with MetS.

Physicochemical parameters - hydration performance relationship of the new endodontic cement MTA Repair HP.

BACKGROUND: To characterize the chemical composition and textural parameters of the MTA Repair HP precursor powder and their influence to hydration performance. MATERIAL AND METHODS: Un-hydrated precursor material was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray fluorescence (XRF), laser diffraction (LD), N2 physisorption and field emission gun scanning electron microscopy (FEG-SEM). Setting time was assessed according to ASTM specification C 266. Hydrated material was analysed by XRD, FT-IR, energy dispersive X-ray (EDX) analysis and FEG-SEM. RESULTS: Ca3SiO5 and Ca2SiO4, in addition to CaWO4 as radiopacifier are the main compositional phases. Other measured parameter indicates high specific surface area of 4.8 m2 g-1, high aluminium content of 1.7 wt.% and low initial and final setting times of 12 and 199 min, respectively. Singular microstructural features consisting of high aspect ratio nanoparticles are main constituents of un-hydrated precursor. Besides, FEM-SEM observation shows notably growth of hexagonal shaped plate-like morphologies homogeneously distributed along the sample during hydration process. CONCLUSIONS: The short setting time measured for HP Repair, is correlated with high surface area of precursor powder, high Al content and the absence of compositional sulphate phases. Key words:Bioactive endodontic cements, hydration performance, MTA HP Repair, physicochemical parameters.

Higher hydration performance and bioactive response of the new endodontic bioactive cement MTA HP repair compared with ProRoot MTA white and NeoMTA plus.

The aim of this study was to characterize the hydration performance and the bioactive response of the new bioactive endodontic cement MTA HP repair (HP), comparing its physicochemical parameters with those of ProRoot MTA White (Pro) and NeoMTA Plus (Neo). Un-hydrated precursor materials were characterized by X-ray fluorescence, laser diffraction, N2 physisorption and field emission gun scanning electron microscopy (FEG-SEM). Setting time was assessed according to ASTM specification C 266. Hydrated materials were analyzed by X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR) and (FEG-SEM). Bioactivity evaluation in vitro was carried out, by soaking processed cement disk in simulated body fluid (SBF) during 168 h. The cements surface was studied by FT-IR, FEG-SEM, and energy dispersive X-ray. Release to the SBF media of ionic degradation products was monitored using inductively coupled plasma atomic emission spectroscopy. HP showed shorter initial setting time compared to Pro and Neo and produce a quick and effective bioactive response in vitro in terms of phosphate phase surface coating formation. This higher bioactive response for HP is correlated with increasing calcium aluminate content, increasing surface area of un-hydrated powder precursor and the increasing release capacity of Si ionic products of the final hydrated product. The higher bioactive response of MTA HP repair highlights this material, as very interesting to further investigate its performance to improve the outcome of vital pulp therapy procedures. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2109-2120, 2019.

Leptin stimulates DMP-1 and DSPP expression in human dental pulp via MAPK 1/3 and PI3K signaling pathways.

INTRODUCTION: To investigate the physiological function of leptin in human dental pulp, and to determine the specific pathways implicated in its effect. METHODS: Twenty-seven dental pulp samples were obtained from human third molars. Pulp samples were treated with or without human recombinant leptin. Leptin functional effect was analyzed in terms of regulation of the synthesis levels of DSPP and DMP-1, determined by immunoblot. RESULTS: Leptin stimulated DMP-1 and DSPP synthesis in all human dental pulp specimens. The stimulatory effect of leptin on DMP-1 and DSPP synthesis was partially prevented by blocking mitogen-activated protein kinase (MAPK 1/3) and phosphatidylinositol 3 kinase (PI3K) pathways, respectively. CONCLUSIONS: The present study demonstrates the functional effect of leptin in human dental pulp stimulating the expression of DMP-1 and DSPP, both proteins implicated in dentinogenesis. Leptin stimulates DSPP expression via PI3K pathway and DMP-1 synthesis via MAPK 1/3 pathway. These results support the role of leptin in pulpal reparative response, opening a new research line that could have translational application to the clinic in vital pulp therapy procedures.