Mechanisms of transient signaling via short and long prolactin receptor isoforms in female and male sensory neurons.

Prolactin (PRL) regulates activity of nociceptors and causes hyperalgesia in pain conditions. PRL enhances nociceptive responses by rapidly modulating channels in nociceptors. The molecular mechanisms underlying PRL-induced transient signaling in neurons are not well understood. Here we use a variety of cell biology and pharmacological approaches to show that PRL transiently enhanced capsaicin-evoked responses involve protein kinase C ε (PKCε) or phosphatidylinositol 3-kinase (PI3K) pathways in female rat trigeminal (TG) neurons. We next reconstituted PRL-induced signaling in a heterologous expression system and TG neurons from PRL receptor (PRLR)-null mutant mice by expressing rat PRLR-long isoform (PRLR-L), PRLR-short isoform (PRLR-S), or a mix of both. Results show that PRLR-S, but not PRLR-L, is capable of mediating PRL-induced transient enhancement of capsaicin responses in both male and female TG neurons. However, co-expression of PRLR-L with PRLR-S (1:1 ratio) leads to the inhibition of the transient PRL actions. Co-expression of PRLR-L deletion mutants with PRLR-S indicated that the cytoplasmic site adjacent to the trans-membrane domain of PRLR-L was responsible for inhibitory effects of PRLR-L. Furthermore, in situ hybridization and immunohistochemistry data indicate that in normal conditions, PRLR-L is expressed mainly in glia with little expression in rat sensory neurons (3-5%) and human nerves. The predominant PRLR form in TG neurons/nerves from rats and humans is PRLR-S. Altogether, PRL-induced transient signaling in sensory neurons is governed by PI3K or PKCε, mediated via the PRLR-S isoform, and transient effects mediated by PRLR-S are inhibited by presence of PRLR-L in these cells.

Microbiome Changes during Regenerative Endodontic Treatment Using Different Methods of Disinfection.

INTRODUCTION: The purpose of this study was to characterize qualitatively and quantitatively the changes in the endodontic microbiome, in teeth with necrotic pulp, open apexes, and apical periodontitis, with 3 antimicrobial protocols, undertaken in a multicenter clinical trial. METHODS: Microbiological samples were collected from 116 regenerative endodontic teeth, and 97 qualified for inclusion. The teeth were randomly divided into 3 treatment groups: apexification (APEX), regeneration (REGEN), and revascularization (REVASC), all in 2 appointments. The group variables in the first appointment irrigants, and second appointment irrigants and medicaments were as follows: APEX: 5.25%-6% NaOCl, 5.25%-6% NaOCl + 17% EDTA and calcium hydroxide; REGEN: 1.25% NaOCl, 17% EDTA, and 0.1 mg/mL triple antibiotic paste (TAP); and REVASC 5.25% NaOCl, saline, and 1 g/mL TAP, respectively. Sampling was done upon access (S0), after irrigation in the first appointment (S1), and after using medication and irrigation in the second appointment (S2). RESULTS: Quantitative polymerase chain reaction analysis of the 16S ribosomal RNA gene showed significant reduction in bacterial load from S0 to S2 in all groups; however, the APEX and REVASC groups had significantly less residual DNA than the REGEN group (P = .0045). The relative abundance of Bacteroidetes, Fusobacteria, Spirochaetes, and Synergistetes were reduced with the treatment rendered. However, relative abundance of Firmicutes and Actinobacteria was not changed, and that of Proteobacteria increased. LEfSe analysis showed that reduction in bacterial taxa was more in REVASC than APEX, which in turn was more than in REGEN. CONCLUSION: Enhanced antimicrobial protocols lead to better reduction in quantitative and qualitative parameters of the endodontic microflora.

Endocannabinoids Modulate Production of Osteoclastogenic Factors by Stem Cells of the Apical Papilla In Vitro.

INTRODUCTION: Many mediators are produced during pulp inflammation and necrosis, including endocannabinoids (ECbs), which might affect the function of stem cells of the apical papilla (SCAP), cells of paramount importance for root formation, and regenerative endodontic treatment. The aim of this study was to evaluate the production of osteoclastogenesis-related mediators by SCAP modulated by ECbs and lipopolysaccharide (LPS) in vitro. METHODS: SCAP were cultured and treated with ECb anandamide (AEA), 2-arachidonoylglycerol, or N-arachidonoylaminophenol. All groups were incubated in the presence of a vehicle or LPS and the antagonist of transient receptor potential cation channel subfamily V member 1, capsazepine. After 24 hours, the culture medium supernatants were collected for further quantification of tumor necrosis factor alpha, CCL2, macrophage colony-stimulating factor, osteoprotegerin, and receptor activator of nuclear factor kappa B ligand. RESULTS: Small amounts of tumor necrosis factor alpha and receptor activator of nuclear factor kappa B ligand were detected in SCAP supernatants, and none of the experimental conditions altered their production. A down-regulation in constitutive CCL2 production was observed in the AEA group compared with that in the LPS group. The production of macrophage colony-stimulating factor was significantly increased in all groups treated with AEA compared with the control and LPS-treated groups. Osteoprotegerin was significantly increased by AEA alone and by 2-arachidonoylglycerol and N-arachidonoylaminophenol in the presence of LPS and capsazepine. CONCLUSIONS: AEA modulates some of the osteoclastogenic factors produced by SCAP in a bone resorption protective fashion.

Trends in oral and maxillofacial radiology career: A survey.

PURPOSE/OBJECTIVES: To understand the professional aspirations of oral and maxillofacial radiologists (OMRs) by exploring their career choices and their association with educational background, engagement in professional activities, professional values, and overall level of career satisfaction. METHODS: This prospective cross-sectional study surveyed board-certified OMRs in the United States and Canada from September to December 2019. A web-based questionnaire was created comprising 37 multiple-choice questions and an open-ended question focusing on their opinions regarding the profession's future. A thematic approach qualitatively explored open questions. RESULTS: Of the 86 OMRs, 68, 10, and eight were board certified in the United States, Canada, and both countries, respectively. Activities considered "rewarding" included teaching and mentoring (65%) and radiologic reporting (55%). The majority spent approximately 20-30 h/week writing radiographic reports and less than 10 h in research. On an average, OMRs produced 21.9 (SD 12.8) reports per day. Activities considered less rewarding included administrative work (11%) and productivity pressure in institutions. OMRs working in academia reported higher incomes (p < 0.05). Finally, the majority of the OMRs were pleased with their career choices (79%). CONCLUSIONS: There is an association between the contemporary OMRs' satisfaction feeling, teaching/mentoring, and the future challenges of participating in multidisciplinary teams. Overall, diverse career choices lead OMRs to be proud of their profession and significantly satisfied.

Implementation of a modified quality assurance protocol for CBCT machines within UT health San Antonio School of Dentistry.

OBJECTIVES: To implement the quality control assurance protocol (including the re-establishment of baseline data from 2016) to monitor the stability of image quality of CBCT machines located within the UT Health San Antonio School of Dentistry. METHODS AND MATERIALS: Five CBCT machines ProMax 3D Mid® (Planmeca Oy, Helsinki, Finland), 3D Accuitomo XYZ Slice View Tomograph® (Model MCT-1, Type EX-1F8; Fushimi-ku, Kyoto: J. Morita Mfg. Corp), Veraviewepocs 3D (Model R100; Fushimi-ku, Kyoto: J. Morita Mfg. Corp), PreXion3D Excelsior® (PreXion, San Mateo, CA), and i-CAT FLX Series® (Imaging Sciences International, Hatfield, PA) were tested for Artifact, Contrast-to-Noise Ratio, Noise, Spatial Resolution, and Contrast Resolution using a custom insert configuration in the SEDENTEXCT IQ phantom. RESULTS: Four-scan benchmark mean values for Artifact, Contrast-to-Noise, Noise, Spatial Resolution, and Contrast Resolution were determined for the five machines tested with associated alert and action level thresholds calculated. CONCLUSION: This newly developed QA protocol established image quality baseline values. Recommended tests, frequency, and actions levels have been updated and control charts established for future trend analysis to enable proper implementation of a QA protocol monitoring CBCT machines at UT health San Antonio.

Advances in endodontics: Potential applications in clinical practice.

Contemporary endodontics has seen an unprecedented advance in technology and materials. This article aimed to review some of the challenges and advances in the following sections: (1) endodontic imaging, (2) root canal preparation, (3) root canal disinfection, (4) root canal filling, and (4) regenerative endodontic procedures (REPs). Jointly, these advances are aimed at improving the state of the art and science of root canal treatment.