Showa University Dental Hospital

Local administrations of prostaglandins E1 or E2 combined with orthodontic tooth movement can approximately double the rate of tooth movement in monkeys compared to that of the control. Macroscopically, no side-effect was observed in the gingiva and associated structures.

INTRODUCTION: The ligament of Marshall (LOM) or the oblique vein of Marshall (VOM) in the left atrium (LA) is one of the origins of nonpulmonary vein ectopies causing atrial fibrillation. The distributions of myocardial bundles (Marshall bundles; MBs) and autonomic nerves adjacent to the LOM have not been completely elucidated. METHODS AND RESULTS: Twenty-eight human hearts were examined postmortem. The inferolateral LA myocardium was dissected en block and cut perpendicularly to the atrioventricular ring. The specimens were sectioned at 1-mm intervals and stained with hematoxylin and eosin, and Azan-Mallory. In addition, S-100 and tyrosine hydroxylase (TH) were employed for the immunohistochemical analysis of the sympathetic and parasympathetic fibers. In 25 cases, MBs were observed. Although the MBs surrounded the VOM at the coronary sinus (CS) juncture, they gradually diminished in density toward the distal venous branch. The connections of the MBs and LA myocardium were frequently observed in the CS juncture and anterior wall of the left pulmonary vein (PV)-LA junctions. TH-stained sympathetic nerve fibers were densely distributed around the PV-LA junctions. On the other hand, non-TH-stained parasympathetic ganglions were mainly observed at the CS juncture. CONCLUSIONS: MB-LA connections were mainly observed at the CS juncture and PV-LA junctions. The association between sympathetic nerve fibers and MBs was distinct at the PV-LA junctions. At the CS juncture, the regression of the sympathetic nerve fibers and the increase of parasympathetic ganglions were observed. The diverse arrangement and autonomic innervation of MBs seem to characterize the LOM region in humans.

Administration of imidazole and verapamil inhibited the appearance of osteoclasts and bone resorption induced by experimental tooth movement in rats. On the other hand, administration of theophylline and ouabain enhanced the appearance of osteoclasts. A mixed solution of DB cyclic AMP and A-23187 injected in gingiva near the orthodontically-treated teeth caused enhancement of the appearance of osteoclasts and bone resorption.

As the root canal system shows different and complicated anatomies, mechanical instrumentation alone has not the ability to provide a bacteria-free environment in root canals. On the other aspect, necrotic tissue remaining can decrease the effects of root canal irrigants and medicaments and also interfere with the adaptation of root canal fillings to dentin. As a result, certain disinfection and irrigation procedures are required to remove the remaining tissues from the root canal area thoroughly and also be able to eliminate the microorganisms. Triple antibiotic paste (TAP) containing metronidazole, ciprofloxacin and minocycline has been proposed as a root canal medicament due to its antimicrobial effects in endodontic regenerative procedures. The purposes of this review were to determine the properties of TAP drugs and to evaluate the efficiency of TAP on the root canal disinfection, in primary and permanent teeth, along with its affection in regeneration/revascularization procedures. The biocompatibility and disadvantages of this medicament were also discussed.

Thrombus aspiration therapy allows for the examination of thrombus and atheroma fragments in acute coronary syndrome (ACS). Inflammatory cells and platelet activation play key roles in thrombus formation in ACS. However, histopathologic evaluation of thrombi in ACS has not been adequately addressed. We performed histologic analysis of tissue samples obtained by thrombus aspiration therapy. We studied 165 samples from patients with ACS. The area of each sample, percentage of red thrombus, and percentage of white thrombus were measured. Samples were stained immunohistochemically with antibodies against macrophages, activated platelets, and interleukin (IL)-5. Seventy-six samples included atheroma fragments. Macrophages, neutrophils, and activated platelets were observed in thrombi and in atheroma fragments. Eosinophil infiltration was also observed predominantly in the area between white thrombus and red thrombus in 106 samples. We categorized all samples into 3 groups according to the grade of eosinophil infiltration (eos-, eos+, eos++ group). Sample area in the eos++ group was greater than that in the eos- group (P < 0.0001). In addition, the percentage of the red thrombus areas in the eos++ group and the eos+ group was greater than that in the eos- group (P < 0.009, P < 0.02, respectively). However, there was no difference in the percentage of white thrombus area between the 3 groups. Staining for IL-5 was identified in inflammatory cells within thrombi. Eosinophils may play an important role in coronary occlusion by promoting thrombus growth.

OBJECTIVE: The dimensions of oral health-related quality of life (OHRQoL) Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact are the major areas where patients are impacted by oral diseases and dental interventions. The aim of this study was to evaluate whether dental patients' reasons to visit the dentist fit the 4 OHRQoL dimensions. METHODS: Dentists (N = 1580) from 32 countries participated in a web-based survey. For their patients with current oral health problems, dentists were asked whether these problems were related to teeth, mouth, and jaws' function, pain, appearance, or psychosocial impact or whether they do not fit the aforementioned 4 categories. Dentists were also asked about their patients who intended to prevent future oral health problems. For both patient groups, the proportions of oral health problems falling into the 4 OHRQoL dimensions were calculated. RESULTS: For every 100 dental patients with current oral health problems, 96 had problems related to teeth, mouth, and jaws' function, pain, appearance, or psychosocial impact. For every 100 dental patients who wanted to prevent future oral health problems, 92 wanted to prevent problems related to these 4 OHRQoL dimensions. Both numbers increased to at least 98 of 100 patients when experts analyzed dentists' explanations of why some oral health problems would not fit the four dimension. For the remaining 2 of 100 patients, none of the dentist-provided explanations suggested evidence against the OHRQoL dimensions as the concepts that capture dental patients' suffering. CONCLUSION: Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact capture dental patients' oral health problems worldwide. These 4 OHRQoL dimensions offer a psychometrically sound and practical framework for patient care and research, identifying what is important to dental patients.

AIM: The purpose of this review is to address the smear layer removing the ability of root different canal irrigants including ethylenediaminetetraacetic acid (EDTA), a mixture of tetracycline, acid and detergent (MTAD), tetraclean, citric acid, Q-Mix, maleic acid, and smear clear. BACKGROUND: Smear layer is a layer which is produced during instrumentation. It contains both organic and inorganic materials. It may also contain bacteria and their byproduct considering the root canal situation. This layer may prevent the penetration of the healing material introduced to the canal to the interior of the dentinal tubules. In addition, it can affect the adaptation of sealing materials to the root canal walls. REVIEW RESULTS: The smear layer removal ability of MTAD is superior and faster than EDTA. Tetraclean is similarly composed of an acid, an antibiotic, and a detergent. The presence of doxycycline is believed to help the smear layer removal ability of these irrigants. Antibiotics such as tetracycline had similar smear layer removal ability as even citric acid. EDTA is an amino acid with a chelating ability that sequestrates metal ions. Some believed EDTA smear layer removing ability is better than MTAD, tetraclean, SmearClear, and 20% citric acid which is controversial in case of comparison between MTAD and EDTA. Phosphoric acid is efficient enough to be comparable to EDTA in removing the smear layer. Maleic acid is an organic compound with acid etching smear layer removal. Its ability seems to be similar or even better than EDTA. Citric acid as another organic acid is believed to be used as smear removing agent. HEBP is another chelating agent that can be used in combination with NaOCl; however, HEBP is a weak decalcifying agent compared to EDTA and hence cannot be applied as a mere final rinse. QMiX is a combination of CHX, EDTA, and detergent and should be used at final rinse. It is believed that QMiX is as efficient as EDTA. Smear clear is a 17% EDTA solution including an anionic and cationic (cetrimide) surfactant. The ability of QMiX is similar to EDTA. CONCLUSION: There are different canal irrigation solutions with various smear layer removal ability that some should be used as a mere final rinse and some should not. CLINICAL SIGNIFICANCE: The usage of canal irrigation solutions depends on the clinical situation and preference of the dentists. This study provides a good guide for clinician of the field.

The anti-thymic stromal lymphopoietin antibody (tezepelumab) has therapeutical potential for inadequately controlled asthma. However, evidence comparing tezepelumab with other biologics is scarce. To address this issue, we performed a network meta-analysis to compare and rank the efficacy of five treatments (tezepelumab, dupilumab, benralizumab, mepolizumab, and placebo) in overall participants and in subgroups stratified by the thresholds of type 2 inflammatory biomarkers, including peripheral blood eosinophil count (PBEC) and fractional exhaled nitric oxide (FeNO). The primary endpoints were annualized exacerbation rate (AER) and any adverse events (AAEs). In the ranking assessment using surface under the cumulative ranking curve (SUCRA) of AER, tezepelumab ranked the highest overall and across subgroups (based on PBEC and FeNO level thresholds). A significant difference was observed between tezepelumab and dupilumab in the patient subgroup with PBEC < 150, and between tezepelumab and benralizumab in overall participants and the patient subgroup with PBEC ≥ 300 and ≥150, respectively. There was no significant difference in the incidence of AAEs in the overall participants between each pair of five treatment arms. These results provide a basis for the development of treatment strategies for asthma and may guide basic, clinical, or translational research.

To date, there have been no head-to-head randomized controlled trials (RCTs) comparing the safety and efficacy of lorlatinib and alectinib in anaplastic lymphoma kinase (ALK) rearrangement-positive (ALK-p) ALK-inhibitor‒naïve advanced non-small cell lung cancer (NSCLC). We performed a network meta-analysis comparing six treatment arms (lorlatinib, brigatinib, alectinib, ceritinib, crizotinib, and platinum-based chemotherapy) in overall participants and in Asian and non-Asian subgroups. Primary endpoints were progression-free survival (PFS), overall survival (OS), and grade 3 or higher adverse events (G3-AEs). There were no significant differences between lorlatinib and alectinib in overall participants for both PFS (hazard ratio [HR], 0.742; 95% credible interval [CrI], 0.466-1.180) and OS (HR, 1.180; 95% CrI, 0.590-2.354). In the Asian subgroup, there were no significant differences in PFS between lorlatinib and alectinib (HR, 1.423; 95% CrI, 0.748-2.708); however, in the non-Asian subgroup, PFS was significantly better with lorlatinib than with alectinib (HR, 0.388; 95% CrI, 0.195-0.769). The incidence of G3-AEs in overall participants was significantly higher with lorlatinib than with alectinib (risk ratio, 1.918; 95% CrI, 1.486-2.475). These results provide valuable information regarding the safety and efficacy of lorlatinib in ALK-p ALK-inhibitor‒naïve advanced NSCLC. Larger head-to-head RCTs are needed to validate the study results.

BACKGROUND AND OBJECTIVE: Oxidative modification of low-density lipoprotein (LDL) occurs in various diseased tissues and sites of local inflammation. For example, an increased plasma oxidized low-density lipoprotein (OxLDL) level is a well-known risk marker for cardiovascular diseases. Gingival crevicular fluid, the exudate from gingival tissues into the sulci, can be easily collected in a non-invasive manner. However, the possible presence of OxLDL in gingival crevicular fluid has not been studied. In this study, we established a procedure to measure OxLDL in human gingival crevicular fluid. MATERIAL AND METHODS: Human gingival crevicular fluid was sampled with paper points or paper strips. The gingival crevicular fluid samples from healthy gingival sulci (pocket depth < 4 mm, n = 14) were subjected to western blot and/or sandwich ELISA. The amounts of OxLDL and LDL were measured by sandwich ELISA using an anti-oxidized phosphatidylcholine monoclonal antibody and two anti-apolipoprotein B antibodies. Venous blood samples were analyzed biochemically. RESULTS: We tested two methods of gingival crevicular fluid collection, namely paper points and paper strips. Gingival crevicular fluid could be collected very safely with paper points and they showed good recovery of LDL and OxLDL throughout the analysis. Apolipoprotein B, the major protein component in LDL, was detected in gingival crevicular fluid by western blot, and OxLDL was found to be present in gingival crevicular fluid by ELISA. The OxLDL/LDL ratio in gingival crevicular fluid was 17.0 times higher than that in plasma. CONCLUSION: This is the first report to show the presence of apolipoprotein B and apolipoprotein B- oxidized phosphatidylcholine complex, which correspond to LDL and OxLDL, respectively, in gingival crevicular fluid.

Central nervous system (CNS) metastases and acquired resistance complicate the treatment of anaplastic lymphoma kinase (ALK) rearrangement-positive (ALK-p) advanced non-small cell lung cancer (NSCLC). Thus, this review aimed to provide a comprehensive overview of brain metastasis, acquired resistance, and prospects for overcoming these challenges. A network meta-analysis of relevant phase III randomized controlled trials was performed to compare the efficacies of multiple ALK inhibitors by drug and generation in overall patients with ALK-p untreated advanced NSCLC and a subgroup of patients with CNS metastases. The primary endpoint was progression-free survival (PFS). Generation-specific comparison results showed that third-generation ALK inhibitors were significantly more effective than second-generation ALK inhibitors in prolonging the PFS of the subgroup of patients with CNS metastases. Drug-specific comparison results demonstrated that lorlatinib was the most effective in prolonging PFS, followed by brigatinib, alectinib, ensartinib, ceritinib, crizotinib, and chemotherapy. While lorlatinib was superior to brigatinib for PFS in the overall patient population, no significant difference between the two was found in the subgroup of patients with CNS metastases. These results can serve as a foundation for basic, clinical, and translational research and guide clinical oncologists in developing individualized treatment strategies for patients with ALK-p, ALK inhibitor-naive advanced NSCLC.

A novel method was developed to fabricate all-ceramic restorations which comprised CAD/CAM-fabricated machinable ceramic bonded to CAD/CAM-fabricated zirconia framework using resin cement. The feasibility of this fabrication method was assessed in this study by investigating the bonding strength of a machinable ceramic to zirconia. A machinable ceramic was bonded to a zirconia plate using three kinds of resin cements: ResiCem (RE), Panavia (PA), and Multilink (ML). Conventional porcelain-fused-to-zirconia specimens were also prepared to serve as control. Shear bond strength test (SBT) and Schwickerath crack initiation test (SCT) were carried out. SBT revealed that PA (40.42 MPa) yielded a significantly higher bonding strength than RE (28.01 MPa) and ML (18.89 MPa). SCT revealed that the bonding strengths of test groups using resin cement were significantly higher than those of Control. Notably, the bonding strengths of RE and ML were above 25 MPa even after 10,000 times of thermal cycling -adequately meeting the ISO 9693 standard for metal-ceramic restorations. These results affirmed the feasibility of the novel fabrication method, in that a CAD/CAM-fabricated machinable ceramic is bonded to a CAD/CAM-fabricated zirconia framework using a resin cement.

BACKGROUND: Mandibular overdentures retained by a single implant placed in the midline of edentulous mandible have been reported to be more comfortable and function better than complete dentures. Although single-implant overdentures are still more costly than conventional complete dentures, there are a few studies which investigated whether mandibular single-implant overdentures are superior to complete dentures when patient general satisfaction is compared. The aim of this study is to assess patient general satisfaction with mandibular single-implant overdentures and complete dentures. METHODS: This study is a randomized crossover trial to compare mandibular single-implant overdentures and complete dentures in edentulous individuals. Participant recruitment is ongoing at the time of this submission. Twenty-two participants will be recruited. New mandibular complete dentures will be fabricated. A single implant will be placed in the midline of the edentulous mandible. The mucosal surface of the complete denture around the implant will be relieved for 3 months. The participants will then be randomly allocated into 2 groups according to the order of the interventions; group 1 will receive single-implant overdentures first and will wear them for 2 months, followed by complete dentures for 2 months. Group 2 will receive the same treatments in a reverse order. After experiencing the 2 interventions, the participants will choose one of the mandibular prostheses, and yearly follow-up visits are planned for 5 years. The primary outcome of this trial is patient ratings of general satisfaction on 100 mm visual analog scales. Assessments of the prostheses and oral health-related quality of life will also be recorded as patient-reported outcomes. The secondary outcomes are cost and time for treatment. Masticatory efficiency and cognitive capacity will also be recorded. Furthermore, qualitative research will be performed to investigate the factors associated with success of these mandibular denture types. Clinical outcomes, such as implant survival rate, marginal bone loss, and prosthodontic complications, will also be recorded. DISCUSSION: The results of this randomized crossover trial will clarify whether mandibular single implants and overdentures for edentulous individuals provide better patient general satisfaction when compared to conventional complete dentures. TRIAL REGISTRATION: This clinical trial was registered at the University Hospital Medical Information Network (UMIN) Center (UMIN000017883).

Clinically unsuspected metastases to the lateral retropharyngeal nodes from carcinomas of the upper gingiva or maxillary sinus were found in five patients on follow-up CT examinations. Such uncommon metastases may follow the afferent lymphatic channels from the palate or pharyngeal region or arrive by retrograde lymphatics from positive neck nodes. Careful examination of lateral retropharyngeal nodes may be required in cancers of these primary sites.

OBJECTIVE: The aim of this study was to assess the characteristics of an optically stimulated luminescence dosemeter (OSLD) for use in diagnostic radiology and to apply the OSLD in measuring the organ doses by panoramic radiography. METHODS: The dose linearity, energy dependency and angular dependency of aluminium oxide-based OSLDs were examined using an X-ray generator to simulate various exposure settings in diagnostic radiology. The organ doses were then measured by inserting the dosemeters into an anthropomorphic phantom while using three panoramic machines. RESULTS: The dosemeters demonstrated consistent dose linearity (coefficient of variation<1.5%) and no significant energy dependency (coefficient of variation<1.5%) under the applied exposure conditions. They also exhibited negligible angular dependency (≤ 10%). The organ doses of the X-ray as a result of panoramic imaging by three machines were calculated using the dosemeters. CONCLUSION: OSLDs can be utilized to measure the organ doses in diagnostic radiology. The availability of these dosemeters in strip form proves to be reliably advantageous.

ABSTRACT Microorganisms and their by-products play a critical role in pulp and periradicular pathosis. Therefore, one of the main purposes of root canal treatment is disinfection of the entire system of the canal. This aim may be obtained using mechanical preparation, chemical irrigation, and temporary medication of the canal. For this purpose, various irrigation solutions have been advocated. Common root canal irrigants, such as sodium hypochlorite, chlorhexidine, and a mixture of tetracycline, acid, and detergent have been extensively reviewed. The aim of this review was to address the less common newer root canal irrigation solutions, such as citric acid, maleic acid, electrochemically activated water, green tea, ozonated water, and SmearClear. How to cite this article Mohammadi Z, Jafarzadeh H, Shalavi S, Kinoshita JI. Unusual Root Canal Irrigation Solutions. J Contemp Dent Pract 2017;18(5):415-420.

Commonly used irrigants do not always eradicate the entire microbial flora in infected root canals. Therefore, several other strategies, such as photodynamic therapy (PDT) have been developed. Photoactivated disinfection is based on the interaction of a photosensitive antibacterial agent and a light source. It uses a nontoxic dye named photosensitizer (PS) and low-intensity visible light. In oxygen presentation, these combine to produce some cytotoxic species. The PS molecules attach to bacteria membrane. Irradiation with a specific wavelength of the light may lead to the production of singlet oxygen, resulting in rupture of the microbial cell wall. There are several applications for PDT in dentistry. A successful periodontal treatment is based on elimination of bacteria from the infected area. Phenothiazinium PSs have been shown to be highly effective and safe for this purpose. However, scaling/root planing should be performed before the PDT. While performing the PDT, PS should be first injected in the periodontal pocket and allowed to pigment. Then, the special fiber should be inserted 1 mm short of the pocket base and lased. Photodynamic therapy has also been used to disinfect caries dentin before restoration, disinfecting oral tissues before or during surgical procedures, treating denture stomatitis, and treating oral candidiasis in immunocompromised patients. Photodynamic therapy can be used in combination with mechanical instrumentation and chemical antimicrobial agents, such as sodium hypochlo-rite, too. The purpose of this study was to review historical perspective, mechanism of action, and applications of PDT in dentistry and especially in endodontics was reviewed. Furthermore, the effects of PDT on dentin bonding and endo-toxin are discussed. CLINICAL SIGNIFICANCE: Photodynamic therapy has been advocated to increase the disinfection level of the root canal system.

PurposeMany patients require esthetic orthodontic treatment. Aligners have recently become widely used in such cases. However, orthodontic treatment occasionally causes unexpected tooth movement called the bowing effect. For example, when premolars are extracted during treatment, molars tend to tip toward the extracted area. Recently, small composite attachments have been recommended with the aim to generate effective orthodontic force to prevent the bowing effect. However, the mechanism of tooth movement with attachments of aligner-type appliances is not yet clear.Materials and methodsIn this study, we evaluated the effects of attachments on aligner treatment with finite element analyses.ResultsIn this study, the computational results with finite element analyses show that the shape and position of attachments have no influence on tensile force and tipping moment. Differences in delicate positioning of attachments changed the analytical results.ConclusionsWe suggest that appropriate model setting is important to evaluate the effect of attachment by finite element analyses.

Orthodontic mechanical stress reduced the frequency of the appearance of mast cells stainable with toluidine blue in the periodontal ligament on both the pressure and tension sides of rat molar teeth. This effect was seen immediately after insertion of elastic bands between the first and second molars, and the greatest reduction in the number of mast cells stainable with toluidine blue was observed 15 min after insertion.

BACKGROUND AND OBJECTIVE: Recent epidemiological studies have shown a correlation between periodontitis and hyperlipidemia. We have found high levels of oxidized low-density lipoprotein (OxLDL) in the gingival crevicular fluid of dental patients. In the present study, we tried to examine the possible role of OxLDL in periodontal inflammation in vitro. MATERIAL AND METHODS: Cells of the human gingival epithelial cell line Ca9-22 were cultured in media containing OxLDL, and the amounts of interleukin-8 (IL-8) and prostaglandin E(2) (PGE(2)) produced were measured using ELISAs. RESULTS: Production of IL-8 by Ca9-22 cells was significantly increased when the cells were treated with OxLDL, but not with native LDL or acetylated LDL. Production of PGE(2) by Ca9-22 cells was enhanced by co-incubation with OxLDL and interleukin-1 beta (IL-1 beta). Scavenger receptor inhibitors, fucoidan and dextran sulfate, inhibited the OxLDL-induced IL-8 and PGE(2) production in the presence of IL-1 beta. The p(38) MAPK inhibitors SB203580 and SB202190 and the ERK inhibitor PD98059 inhibited the OxLDL-induced IL-8 production. Among oxidized lipids and chemically modified LDL, 7-ketocholesterol enhanced IL-8 production. CONCLUSION: This is the first report to show that OxLDL enhances IL-8 production in epithelial cells.