Stimulation phosphatidylinositol 3-kinase/protein kinase B signaling by Porphyromonas gingivalis lipopolysacch aride mediates interleukin-6 and interleukin-8 mRNA/protein expression in pulpal inflammation.

BACKGROUND/PURPOSE: The signaling mechanisms for Porphyromonas gingivalis lipopolysaccharide (PgLPS)-induced inflammation in human dental pulp cells are not fully clarified. This in vitro study aimed to evaluate the involvement of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in PgLPS-induced pulpal inflammation. METHODS: Human dental pulp cells (HDPCs) were challenged with PgLPS with or without pretreatment and coincubation with a PI3K/Akt inhibitor (LY294002). The gene or protein levels of PI3K, Akt, interleukin (IL)-6, IL-8, alkaline phosphatase (ALP), osteocalcin and osteonectin were analyzed by reverse transcription polymerase chain reaction (PCR), real-time PCR, western blotting, and immunofluorescent staining. In addition, an enzyme-linked immunosorbent assay was used to analyze IL-6 and IL-8 levels in culture medium. RESULTS: In response to 5 µg/ml PgLPS, IL-6, IL-8, and PI3K, but not Akt mRNA expression of HDPCs, was upregulated. IL-6, IL-8, PI3K, and p-Akt protein levels were stimulated by 10-50 µg/ml of PgLPS in HDPCs. PgLPS also induced IL-6 and IL-8 secretion at concentrations higher than 5 µg/ml. Pretreatment and co-incubation by LY294002 attenuated PgLPS-induced IL-6 and IL-8 mRNA expression in HDPCs. The mRNA expression of ALP, but not osteocalcin and osteonectin, was inhibited by higher concentrations of PgLPS in HDPCs. CONCLUSION: P. gingivalis contributes to pulpal inflammation in HDPCs by dysregulating PI3K/Akt signaling pathway to stimulate IL-6 and IL-8 mRNA/protein expression and secretion. These results are useful for understanding the pulpal inflammation and possible biomarkers of inflamed pulp diagnosis and treatment.

Effect of butyrate, a bacterial by-product, on the viability and ICAM-1 expression/production of human vascular endothelial cells: Role in infectious pulpal/periapical diseases.

AIM: To investigate the effects of butyric acid (BA), a metabolic product generated by pulp and root canal pathogens, on the viability and intercellular adhesion molecule-1 (ICAM-1) production of endothelial cells, which are crucial to angiogenesis and pulpal/periapical wound healing. METHODOLOGY: Endothelial cells were exposed to butyrate with/without inhibitors. Cell viability, apoptosis and reactive oxygen species (ROS) were evaluated using an MTT assay, PI/annexin V and DCF fluorescence flow cytometry respectively. RNA and protein expression was determined using a polymerase chain reaction assay and Western blotting or immunofluorescent staining. Soluble ICAM-1 (sICAM-1) was measured using an enzyme-linked immunosorbent assay. The quantitative results were expressed as mean ± standard error (SE) of the mean. The data were analysed using a paired Student's t-test where necessary. A p-value ≤0.05 was considered to indicate a statistically significant difference between groups. RESULTS: Butyrate (>4 mM) inhibited cell viability and induced cellular apoptosis and necrosis. It inhibited cyclin B1 but stimulated p21 and p27 expression. Butyrate stimulated ROS production and hemeoxygenase-1 (HO-1) expression as well as activated the Ac-H3, p-ATM, p-ATR, p-Chk1, p-Chk2, p-p38 and p-Akt expression of endothelial cells. Butyrate stimulated ICAM-1 mRNA/protein expression and significant sICAM-1 production (p < .05). Superoxide dismutase, 5z-7oxozeaenol, SB203580 and compound C (p <  .05), but not ZnPP, CGK733, AZD7762 or LY294002, attenuated butyrate cytotoxicity to endothelial cells. Notably, little effect on butyrate-stimulated sICAM-1 secretion was found. Valproic acid, phenylbutyrate and trichostatin (three histone deacetylase inhibitors) significantly induced sICAM-1 production (p < .05). CONCLUSION: Butyric acid inhibited proliferation, induced apoptosis, stimulated ROS and HO-1 production and increased ICAM-1 mRNA expression and protein synthesis in endothelial cells. Cell viability affected by BA was diminished by some inhibitors; however, the increased sICAM-1 secretion by BA was not affected by any of the tested inhibitors. These results facilitate understanding of the pathogenesis, prevention and treatment of pulpal/periapical diseases.

Cracked teeth: Distribution and survival at 6 months, 1 year and 2 years after treatment.

BACKGROUND/PURPOSE: The unpredictable condition of cracked teeth warrants further investigation and clinical experiences. The purpose of this study was to collect and record data on demographics, clinical characteristics, different treatment modalities and survival of cracked teeth at 6-month, 1-year and 2-year recalls. METHODS: 77 cracked teeth from 65 patients were included. Data on demographics, clinical parameters, treatment modalities and recall were collected. Binomial, multinomial and chi square tests were used for statistical analysis. RESULTS: Most cracked teeth occurred in patients greater than 40 years old (p < 0.01). Cracked teeth themselves were most often molars (79.22%; p < 0.01), a non-terminal tooth in the arch (62.34%; p < 0.05) and nonendodontically-treated teeth (94.81%; p < 0.01). Cracked teeth exhibited pain to percussion (63.64%, p < 0.05) or biting (74.03%; p < 0.01), and no or only positive mobility (76.62%; p < 0.01). Cracks were most often oriented in the mesiodistal direction (68.83%; p < 0.01). Higher survival rates were noted in cracked teeth lacking pre-operative pain to palpation or spontaneous pain, and with no or only positive mobility at 6-month and 1-year recalls. In vital cracked teeth, higher survival rates were noted in teeth lacking pre-operative pain to palpation and with no or only positive mobility at 2-year recalls. CONCLUSION: The absence of pre-operative palpation discomfort, spontaneous pain and minimal mobility, as well as the presence of pulp vitality were associated with higher survival rates of cracked teeth at all recall times. Results are useful for diagnosis and outcomes-based treatment planning of cracked teeth.

Characterization of Phosphorus Species in Human Dentin by Solid-State NMR.

The rat has been considered as an appropriate animal model for the study of the mineralization process in humans. In this work, we found that the phosphorus species in human dentin characterized by solid-state NMR spectroscopy consist mainly of orthophosphate and hydrogen phosphate. Some orthophosphates are found in a disordered phase, where the phosphate ions are hydrogen-bonded to structural water, some present a stoichiometric apatite structure, and some a hydroxyl-depleted apatite structure. The results of this study are largely the same as those previously obtained for rat dentin. However, the relative amounts of the various phosphorus species in human and rat dentin are dramatically different. In particular, stoichiometric apatite is more abundant in human dentin than in rat dentin, whereas the converse is true for disordered-phase orthophosphates. Furthermore, spatial proximity among all phosphorus species in human dentin is identical within experimental error, in contrast to what observed for rat dentin. Although it is not clear how these spectroscopic data could relate to the hierarchical structure or the mechanical properties of teeth, our data reveal that the molecular structures of human and rat dentin at different growth stages are not exactly the same.

Outcome assessment of apical surgery: A study of 234 teeth.

BACKGROUND/PURPOSE: Apical surgery is an option for management of endodontically-treated tooth with persistent periapical lesions or symptom and sign. The objective of this study was to investigate the correlation between the demography, preoperative, postoperative factors and healed rate of apical surgery. METHODS: Subjects were retrospectively collected from patients who received apical surgery/apicoectomy at the Endodontic Department, National Taiwan University Hospital from January 2013 to June 2015. The standard apical surgery procedures were performed. The demography, preoperative clinical and radiographic examination data as well as postoperative variables were collected. The outcome assessment was carried out after surgery. Statistical analysis was performed by chi square test to evaluate the potential outcome predictors. RESULTS: Total 187 patients and 234 teeth receiving apical surgery were included. 53 male and 134 female patients were collected. The age was ranged between 17 and 89 years old and the mean age was 43.64 years old. Better healed rate with significant differences were observed in female patient (p < 0.05), age ≤60 years old (p < 0.01), preoperative root canal filling material >2 mm short of apex (p < 0.01), lesion size from ≤2 mm to ≤12 mm (p < 0.05) and follow-up period â‰§12 months (p < 0.01) groups. CONCLUSION: Gender, age, preoperative root canal filling material extent, lesion size and follow-up period may affect the outcome of apical surgery. Tooth type, post, prosthesis, and lesion area showed no marked effect on apical healing. These results provide more detailed information for the clinical practitioners to make treatment plans and are important for clinical endodontic practices.

Diversity-Oriented Synthesis of Furo[3,2-c]coumarins and Benzofuranyl Chromenones through Chemoselective Acylation/Wittig Reaction.

A highly efficient and chemoselective one-pot protocol for the diversity-oriented synthesis of two types of coumarin-based formal cross-coupling adducts, furo[3,2-c]coumarins and 3-benzofuranyl chromenones, is described. Key attributes of the methodology are an initial chemoselective acylation of functionalized phosphorus zwitterions and a subsequent chemoselective intramolecular Wittig reaction that preferentially resulted in one of the two coumarin derivatives in high yield, depending on relative reactivities and the addition sequence of the acylating agents.

Chemo- and Diastereoselective Michael-Michael-Acetalization Cascade for the Synthesis of 1,3-Indandione-Fused Spiro[4.5]decan Scaffolds.

A novel, organobase-catalyzed and highly chemoselective Michael-Michael-acetalization cascade is presented for the efficient synthesis of spiro-indandione skeletons. Following this very simple protocol, a broad range of products was obtained in good yields with excellent diastereocontrol. The role of steric factors in the acetalization step was evaluated.

Enantioselective Synthesis of Polysubstituted Benzopyrano[3,4-c]pyrrolidine Frameworks via [3 + 2] Cycloaddition of Azomethine Ylides and Coumarin Derivatives.

An enantioselective synthesis of benzopyrano[3,4-c]pyrrolidine derivatives via organocatalyzed [3 + 2] cycloaddition has been achieved. Cinchona alkaloid-derived organocatalysts as Brønsted bases have been examined for this asymmetric cycloaddition of o-hydroxy aromatic aldimines with 3-substituted coumarins. An unexpected rearrangement of the quaternary acyl moiety in the products resulted in an in situ protection of the o-hydroxy group.

Preparation of functionalized heteroaromatics using an intramolecular Wittig reaction.

The development of efficient methods for the synthesis of heteroaromatic compounds is always of great importance for chemists. In this 'Perspective', we describe a general approach for the synthesis of functionalized heteroaromatics via intramolecular Wittig reactions. In all cases, the reaction proceeds via in situ generated phosphorus ylides. We especially emphasize the importance of chemoselective intramolecular Wittig reactions using designed Michael acceptors and suitable acyl chloride as trapping reagents, which allows formation of two different classes of heteroaromatics from the same substrates. This metal-free approach is quite general and works in a number of examples, furnishing the corresponding products in moderate to good yields under relatively mild reaction conditions.

Effects of surface treatments of bioactive tricalcium silicate-based restorative material on the bond strength to resin composite.

OBJECTIVES: This study aimed to enhance the bond strength between Biodentine™ (BD), a bioactive tricalcium silicate (C3S) based material, and resin composite through various surface treatments. METHODOLOGY: BD samples were immersed in either double distilled water or Hank's Balanced Salt Solution and analyzed using X-ray Diffraction (XRD). Shear bond strength (SBS) evaluations of BD were performed using Prime & Bond™ NT (PNT), Single Bond Universal (SBU), Xeno V (Xeno), and glass ionomer cement (GIC) following various etching durations (0 s/ 15 s/ 30 s/ 60 s with 37.5% phosphoric acid). Two primers, RelyX™ Ceramic Primer (RCP) and Monobond ™ Plus (MBP), were chosen to prime BD for SBS enhancement. Fractography and bonding interfaces were examined with energy dispersive X-ray spectroscopy (EDS)/ scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). RESULTS: XRD confirmed BD's main compositions as C3S, Ca(OH)2, CaCO3 and ZrO2 after 14 days crystal maturation. Etched BD did not improve SBS. GIC exhibited the lowest SBS (p < 0.05) among all adhesives, regardless of the etching mode (all < 1 MPa). The highest SBS (17.5 ± 3.6 MPa, p < 0.05) was achieved when BD primed with MBP followed by SBU application. FTIR and EDS showed γ-MPTS and10-MDP within the MBP primer interacted with C3S and ZrO2 of BD, achieving enhanced SBS. Most specimens exhibited mixed or cohesive failure modes. Significance BD's subpar mechanical properties and texture may contribute to its poor adhesion to resin composite. Pretreating BD with MBP primer, followed by SBU adhesive is recommended for improving bond strength.

Surgical repair of external cervical resorption - Prognosis and prognostic factors.

Background/purpose: External cervical resorption (ECR) is an aggressive form of root resorption, which etiology is unclear and its prognosis remains unpredictable. The purpose of this study was to investigate the prognosis and potential prognostic factors of ECR-affected teeth after surgical intervention for external repair with/without root canal treatment. Materials and methods: Treated ECR cases from 2009 to 2019 were collected retrospectively. The survival of the teeth and the status of root resorption were assessed during the follow-up period. Potential prognostic factors were analyzed with log-rank test and Kaplan-Meier statistics. Results: A total of 42 treated ECR-affected teeth were enrolled. The two-year survival rate was 71.20% [54.16%, 93.59%]. Persistent root resorption was the main complication after treatment. Patients with multiple ECR-affected teeth had greater recurrent potential than patients with solitary ECR-affected teeth. Prolonged calcium hydroxide dressing may contribute to a more favorable clinical outcome. Gender, age, tooth position and the need for root canal treatment did not show statistically significant effect on the prognosis. Conclusion: The current surgical method was able to arrest ECR in most cases. However, the case type (the number of ECR-affected teeth per patient) could highly affect the prognosis of the teeth. Clinicians should consider long-term calcium hydroxide dressing in case of pulp involvement to achieve better results.

Organocatalytic enantioselective direct vinylogous Michael addition of γ-substituted butenolides to 3-aroyl acrylates and 1,2-diaroylethylenes.

Adding value: The direct vinylogous Michael addition of γ-substituted butenolides with a series of 3-aroyl acrylates and 1,2-diaroylethylenes has been demonstrated. This organocatalytic method delivers highly enantio- and diastereomerically pure γ,γ-disubstituted butenolides with adjacent quaternary and tertiary stereocenters (see scheme).

An efficient organocatalytic enantioselective synthesis of spironitrocyclopropanes.

An organocatalytic asymmetric synthesis of spironitrocyclopropanes has been demonstrated starting from 2-arylidene-1,3-indandiones and bromonitroalkanes catalyzed by a cinchona-derived bifunctional organocatalyst. The products were obtained with excellent enantioselectivities, diastereoselectivities and with good yields.

Budget Impact Analysis of Comprehensive Genomic Profiling in Advanced Non-Small Cell Lung Cancer in Taiwan.

OBJECTIVES: The concept of precision oncology using genetic testing has become popular for cancer treatment in recent years. This research aimed to evaluate the financial impact of comprehensive genomic profiling (CGP) in patients with advanced non-small cell lung cancer before receiving any systemic treatments, compared with current practice using single-gene testing, in the hope that the findings can inform the National Health Insurance Administration the decision regarding CGP reimbursement. METHODS: A budget impact analysis model was developed comparing the sum of gene testing costs, the first-line and subsequent systemic treatment costs, and other medical costs between the current practice of traditional molecular testing and the new test strategy of CGP. The evaluation time horizon is 5 years from the perspective of the National Health Insurance Administration. Outcome endpoints were incremental budget impact and life-year gained. RESULTS: This research indicated CGP reimbursement would benefit 1072 to 1318 more patients receiving target therapies than the current practice and consequently had incremental 232 to 1844 life-years gained from 2022 to 2026. The new test strategy also led to higher gene testing cost and systemic treatment cost. Nevertheless, less medical resource utilization and better patient outcome were demonstrated. The incremental budget impact ranged from US dollar 19 to US dollar 27 million in the 5-year period. CONCLUSION: This research shows that CGP could pave the way for personalized healthcare with moderate increase of National Health Insurance budget.

The multi-factor analysis of computer-based test scores in objective structured clinical examination of clerkship in school of dentistry, National Taiwan University.

Background/purpose: The objective structured clinical examination (OSCE) is a test designed to test technical, clinical, and practical competency in medicine teaching. This study tried to evaluate the influencing factors of the computer-based tests (CBT) results for dental students. Materials and methods: The 32 5th-year dental students of the dental school of National Taiwan University (NTU) joined preclinical CBT. The contents of CBT included clinical knowledge and practical skills of nine dental specialties. Twenty single-choice questions were played with the PowerPoint 2016 on a desktop, and the playing time for each question was 30 s. Several factors including the gender, age, and dental student admission ways (with or without the skill tests) were evaluated. Also, the comparison between the clerk's grade and CBT scores of nine dental specialties was performed. The students also filled the feedback questionnaire about the examination questions and suggestions for the CBT. Results: There were no significant differences in the mean CBT scores between male and female dental students, between two groups of dental students with or without the skill tests in the admission process, and among three different age groups of dental students. The clerk's scores were not directly related to the CBT scores. Conclusion: The CBT has been well-intentioned in dental education since 2022 in Taiwan. The CBT results revealed that the conjunction of knowledge from the textbook and clinical observation should be enhanced. The guideline should be established to integrate CBT into preclinical education and promote the performance of clinical work of dental students.

The analysis and feedback from the performance of pre-clinical operation skills tests for clerkship in School of Dentistry, National Taiwan University in 2022.

Background/purpose: The simulated pre-clinical operation skill test (PCOST) is part of the objective structured clinical examination (OSCE) and designed for clinical practice using manikins, physical typodonts, and instruments in the laboratory. This study tried to evaluate the influencing factors of the PCOST results for dental students. Materials and methods: The 32 5th-year dental students of the dental school of National Taiwan University (NTU) joined the PCOST. The contents of PCOST included two specialties: operative dentistry (OD) and prosthodontics (PS). The examination content of OD was tooth 36 mesio-occluso-distal (MOD) cavity preparation, and that of PS was crown preparation and temporary crown fabrication of tooth 11. Several factors including the gender, age, and dental student admission ways (with or without the skill tests) were evaluated. Each scoring item was calculated. The students also filled the feedback questionnaire about the examination questions and suggestions for the PCOST. Results: For both OD and PS, there were no significant differences in the mean PCOST scores between male and female dental students, between two groups of dental students with or without the skill tests in the admission process, and among three different age groups of dental students. According to the feedback questionnaire from the participated dental students, they were satisfied with the PCOST. Conclusion: The PCOST is a good simulated examination in clinical practice. However, we still need to collect more PCOST data and feedback to revise the guideline of the PCOST, and to promote the performance of clinical works of dental students.

The prone position ventilation (PPV) as an approach in pregnancy with acute respiratory distress syndrome (ARDS).

OBJECTIVE: In Taiwan, the overall incidence of acute respiratory distress syndrome (ARDS) is 15.74 per 100,000 person-years, the mortality rate is 57.8%, and its overall prevalence in the intensive care unit (ICU) is 10.4%. Women who are pregnant and have ARDS have a high risk of fetal death and fetal asphyxia. CASE REPORT: A 26-1/7-week pregnant woman presented with upper respiratory infection symptoms progressing to ARDS. While receiving ventilation, maintaining a prone position is an option for pregnant patients with severe ARDS. This case demonstrated a supplementary approach for pregnant women with ARDS. CONCLUSION: Prone position ventilation is indicated for pregnant women, as for any patient with ARDS. The Proning Severe ARDS Patients trial showed no difference in the complication between pregnant patients and other groups.

Birth choices after caesarean in Taiwan: A mixed methods pilot study of a decision aid for shared decision making.

BACKGROUND: Taiwan has a high national caesarean rate coupled with a low vaginal birth after caesarean (VBAC) rate. Studies suggest that women do not receive sufficient information about birth choices after caesarean in Taiwan and shared decision making (SDM) is not an expectation. This pilot study aimed to test the feasibility of using a birth choices decision aid to improve women's opportunity for engagement in SDM about birth after cesarean. METHODS: A two-phase sequential mixed methods pilot study was conducted in a regional hospital in northern Taiwan. Phase I involved a randomized pre-test and post-test experimental design. Participants with one previous caesarean section (CS) were recruited at 14-24 weeks. A total of 65 women completed a baseline survey and were randomly allocated to either the intervention (birth choice decision aid booklet) or usual care (general maternal health booklet) group. A follow up survey at 37-38 weeks measured change in decisional conflict, knowledge, and birth mode preference. Birth outcomes and satisfaction were assessed one month after birth. Phase II consisted of postnatal interviews with women at one month after birth, to explore women's decision making experiences, using a constant comparative analytic technique and thematic analysis. RESULTS: Decisional conflict was relatively low at baseline for all women. Although there were reductions in decisional conflict at follow up, differences between groups were not statistically significant. Women's early preferences regarding mode of birth influenced their knowledge-seeking behaviors and expectations or intention for engaging in SDM during pregnancy. Improvements in knowledge for the decision aid group were larger than for the usual care group, although differences between groups were not statistically significant. Four themes related to key factors in decision making were clarity, safety and risk, consistency, and support. CONCLUSION: A cultural shift is needed to align expectations and relationships towards SDM for birth in Taiwan. Simulation-based strategies and tailored communication skills should be explored to enhance skills in decision coaching for providers. Use of interactive multimedia technology may provide opportunities to increase engagement with tools and support women during decision consultations. Midwife-led continuity of care models may also be beneficial in empowering women to actively share decisions and achieve the birth that is best for them.

Cytotoxicity and genotoxicity of DMABEE, a co-photoinitiator of resin polymerization, on CHO-K1 cells: Role of redox and carboxylesterase.

The 4-dimethylaminobenzoic acid ethyl ester (DMABEE) is an important co-initiator for resin polymerization in dental resinous materials. As a radical forming chemical with high lipophilicity, the genotoxicity and cytotoxicity of DMABEE deserve prudent investigation. In this study, we found that DMABEE reduced the viability and proliferation of Chinese hamster ovary (CHO-K1) cells in a dose-dependent manner, and altered cell morphology at higher concentrations. G0/G1 cell cycle arrest was induced by DMABEE at 0.25-0.75 mM, and cell proportion of sub-G0/G1 phase was significantly elevated at 1 mM while cell apoptosis was observed. Genotoxic effect was noted when cells were treated by 0.1 mM DMABEE, as revealed by increase of micronucleus formation. Reactive oxygen species overproduction was observed as cells treated with 0.75 and 1 mM, while elevation of intracellular glutathione was noticeable since 0.1 mM. Contrary to our expectation, pretreatment by N-acetyl-l-cysteine enhanced the toxicity of DMABEE on CHO-K1 cells. Catalase mildly reduced the toxic effect and carboxylesterase showed obvious ability to reverse the toxicity of DMABEE. These findings highlight the mechanism of DMABEE toxicity and provide clues for safety improvement of its application in clinical dental treatment.

Invasive Cervical Resorption-Distribution, Potential Predisposing Factors, and Clinical Characteristics.

INTRODUCTION: The purpose of this study was to investigate the distribution, predisposing factors, and clinical characteristics of invasive cervical resorption (ICR). METHODS: Cases with ICR from 2009-2019 were collected. Clinical records and radiographs were reviewed. Descriptive analysis was performed in combination with univariate analysis and the Fisher exact test. RESULTS: A total of 63 ICR teeth from 31 patients (14 men and 17 women) were found. The patients' ages ranged from 18-81 years, with a mean age of 45.77 years. Most patients had a single ICR lesion. Among the 63 ICR teeth, maxillary anterior teeth (47.62%) were the most commonly affected followed by maxillary premolars (20.63%). Maxillary teeth (76.19%) were more prone to ICR than mandibular teeth (23.81%). Most patients denied all major systemic diseases. The most common dental-related factors were dental/orofacial trauma (33.33%), periodontal treatment (26.98%), restoration/crown (17.46%), and orthodontic treatment (15.87%). Most teeth showed no percussion/palpation pain, probing depth >3 mm, abscess formation, sinus tracts, or periapical lesions. The pulp status was mainly vital (73.02%). The presence of percussion pain and probing depth differed significantly among Heithersay ICR classification groups. CONCLUSIONS: ICR showed no difference in sex or age. Maxillary anterior teeth were the most affected in a Taiwanese population. Traumatic injury, periodontal treatment, and orthodontic treatment were the significant predisposing factors. Furthermore, affected teeth typically lacked clinical signs and symptoms. Radiographic examination is critical for early diagnosis. In advanced cases, deep pockets and abscess formation were seen. These results are helpful for the diagnosis of ICR and further effective treatment.