1.The mechanical properties of 3D printed denture base resin incorporating essential oil microcapsules
Steve AN ; Jane Lesleigh EVANS ; Stephen HAMLET ; Robert Matthew LOVE
The Journal of Advanced Prosthodontics 2023;15(4):189-201
Purpose:
The aim of this study was to investigate the mechanical properties of three-dimensional (3D) printed denture base resin incorporating microcapsules containing plant essential oils.
Materials and Methods:
Denture base specimens containing up to 3% w/v essential oil microcapsule powders (MCPs), i.e., eucalyptus, geranium, lavender, menthol, and tea tree, in two resins (Detax and NextDent 3D+) were 3D printed using two printers (Asiga and NextDent 5100). The dispersion and interaction of the MCPs in the resin were assessed by SEM while the mechanical properties of the incorporated denture base including flexural strength (MPa), flexural modulus (MPa), Vickers hardness (VHN), and surface roughness (Ra) were also subsequently evaluated. Statistical analysis of any differences in mean values was determined using a two-way ANOVA with Tukey’s post hoc testing (α = .05).
Results:
The spherical shape of the MCPs was maintained during the mixing and polymerization/printing process. However, the Detax-Asiga group showed significant agglomeration of the MCPs even at the lowest MCP concentration levels (0.5% w/v). Overall, as the microcapsule concentration increased, the mean flexural strength decreased, though the menthol MCP groups remained compliant with the ISO standard. The flexural modulus and harness remained relatively unchanged, and the flexural modulus complied with the ISO standard regardless of the MCP concentration. Surface roughness increased with the addition of the MCPs but also remained below that required for clinical acceptance.
Conclusion
Incorporation of microencapsulated plant essential oils into 3D printed denture base resin was successfully achieved. While incorporation negatively influenced flexural strength and surface roughness, little effect on flexural modulus and Vickers hardness was demonstrated.
2.An approach to building Field Epidemiology Training Programme (FETP) trainees’ capacities as educators
Matthew M Griffith ; Ariuntuya Ochirpurev ; Takuya Yamagishi ; Shingo Nishiki ; Baigalmaa Jantsansengee ; Tamano Matsui ; Kazunori Oishi
Western Pacific Surveillance and Response 2018;9(3):1-3
Field Epidemiology Training Programmes (FETPs), which are modelled after the Centers for Disease Control and Prevention’s Epidemic Intelligence Service programme, began in 1980 and have produced graduates in more than 70 countries, including 12 in the Western Pacific Region.1,2 These programmes aim to “build sustainable capacity for detecting and responding to public health threats” and “develop expertise so that disease outbreaks can be detected locally and prevented from spreading”.3 FETPs thus include training in applied epidemiology and public health services. FETP trainees and graduates, however, often have additional responsibilities: mentoring newer trainees, supervising in the field, leading short training courses, facilitating meetings, etc. Programmes therefore must provide trainees with the knowledge and skills to fulfil these responsibilities.
3.Epidemiology of vaccine-preventable diseases in Japan: considerations for pre-travel advice for the 2019 Rugby World Cup and 2020 Summer Olympic and Paralympic Games
Matthew M Griffith ; Munehisa Fukusumi ; Yusuke Kobayashi ; Yusuke Matsui ; Shingo Nishiki ; Reiko Shimbashi ; Saeko Morino ; Tomimasa Sunagawa ; Keiko Tanaka-Taya ; Tamano Matsui ; Kazunori Oishi
Western Pacific Surveillance and Response 2018;9(2):26-33
Introduction:
In 2019 and 2020, Japan will host two international sporting events estimated to draw a combined 22 million visitors. Mass gatherings like these ones increase the risk of spread of infectious disease outbreaks and international transmission. Pre-travel advice reduces that risk.
Methods:
To assist ministries of health and related organizations in developing pre-travel advice, we summarized national surveillance data in Japan (2000–2016, to the extent available) for rubella, invasive pneumococcal disease, measles, non-A and non-E viral hepatitis, hepatitis A, invasive Haemophilus influenzae disease, tetanus, typhoid fever, invasive meningococcal disease, Japanese encephalitis, influenza, varicella, mumps and pertussis by calculating descriptive statistics of reported cases and reviewing trends. (See Annex A for details of reviewed diseases.)
Results:
Our findings showed notable incidences of rubella (1.78 per 100 000 person-years), influenza (243.5 cases per sentinel site), and mumps (40.1 per sentinel site); seasonal increases for influenza (November–May) and Japanese encephalitis (August–November); and a geographical concentration of Japanese encephalitis in western Japan. Measles cases decreased from 11 013 in 2008 to 35 in 2015, but outbreaks (n = 165 cases) associated with importation occurred in 2016. Though invasive meningococcal disease incidence was only 0.03 per 100 000, international transmission occurred at a mass gathering in Japan in 2015.
Discussion
Ministries of health and related organizations should use these findings to develop targeted pre-travel advice for travellers to the 2019 Rugby World Cup and the 2020 Summer Olympic and Paralympic Games, especially for mumps, measles, rubella, influenza, and meningitis. Travellers with increased exposure risk should also be advised about hepatitis A and Japanese encephalitis.
4.Defining the Normal Trends of Serum Creatine Kinase Levels Following Spinal Surgery
Matthew GRIFFITH ; Kenneth Aaron SHAW ; Michael BAIRD ; Patrick RUSHFORD ; Victoria SHAW ; Aaron ROBERTS ; David M GLOYSTEIN
Asian Spine Journal 2019;13(3):386-394
STUDY DESIGN: Prospective, prognostic study, level II evidence. PURPOSE: To define the normal change in the creatine kinase (CK) levels in patients undergoing prone or supine lumbar or cervical spine surgery and to determine if positioning influences the postoperative changes in the CK levels. OVERVIEW OF LITERATURE: Spine surgery is one of the most commonly performed and fastest growing areas of surgery in the United States. Thus, the various possible complications need to be understood, and risk factors for these complications need to be mitigated. One of the rare complications, reported in the literature as small case series and case reports, is rhabdomyolysis, diagnosed by high CK levels. Thus far, very few studies have examined the rise in CK levels following spine surgery, and to our knowledge, none has assessed the potential association of surgical positioning and the rise in CK levels. METHODS: We retrospectively analyzed 94 patients. We obtained their preoperative CK levels, and re-assessed their CK levels at postoperative day (POD) 1, 2, and 3, as well as at their 2-week follow-up. The data were analyzed with respect to the spine level and positioning to determine if positioning had any effect on the postoperative rise in the CK level. RESULTS: Total 94 consecutive patients were enrolled in this study. The average preoperative CK level was 179.64, and the average CK level was 847.04 on POD 1. Prone positioning showed a greater rise in the CK levels following surgery than the supine positioning. In a similar manner, lumbar procedures led to a larger rise in the CK levels than cervical surgery. Prone/lumbar surgery showed the largest increase among all groups. Finally, revision surgery and instrumentation both increased the postoperative CK levels. CONCLUSIONS: This study demonstrated that positioning can affect the postoperative CK level rise, with patients undergoing prone/lumbar surgery showing the greatest rise in the postoperative CK levels. This rise, however, may be related to paraspinal muscle damage, rather than the positioning itself.
Creatine Kinase
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Creatine
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Follow-Up Studies
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Humans
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Paraspinal Muscles
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Prospective Studies
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Retrospective Studies
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Rhabdomyolysis
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Risk Factors
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Spine
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United States
5.Preventing Construct Subsidence Following Cervical Corpectomy: The Bump-stop Technique
Kenneth Aaron SHAW ; Matthew GRIFFITH ; Edward T MOTTERN ; David M GLOYSTEIN ; John G DEVINE
Asian Spine Journal 2018;12(1):156-161
Cervical corpectomy is a viable technique for the treatment of multilevel cervical spine pathology. Despite multiple advances in both surgical technique and implant technology, the rate of construct subsidence can range from 6% for single-level procedures to 71% for multilevel procedures. In this technical note, we describe a novel technique, the bump-stop technique, for cervical corpectomy. The technique positions the superior and inferior screw holes such that the vertebral bodies bisect them. This allows for fixation in the dense cortical bone of the endplate while providing a buttress to corpectomy cage subsidence. We then discuss a retrospective case review of 24 consecutive patients, who were treated using this approach, demonstrating a lower than previously reported cage subsidence rate.
Humans
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Pathology
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Retrospective Studies
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Spine
6.Lessons from COVID-19-free Vanuatu: intensive health operations for Phase 1 of repatriation and quarantine, May–July 2020
Posikai Samuel Tapo ; Tessa B Knox ; Caroline van Gemert ; Obed Manwo ; Edna Iavro ; Wendy Williams ; Rosaria Maurice ; Griffith Harrison ; Matthew Cornish ; Michael Benjamin ; Vincent Atua ; Jimmy Obed ; Geoff Clark ; Philippe Guyant ; Basil Leodoro ; Len Tarivonda
Western Pacific Surveillance and Response 2021;12(1):61-68
International borders to Vanuatu closed on 23 March 2020 due to the global COVID-19 pandemic. In May–July 2020, the Government of Vanuatu focused on the safe and timely return of citizens and residents while ensuring Vanuatu remained COVID-19 free. Under Phase 1 of repatriation, between 27 May and 23 June 2020, 1522 people arrived in the capital, Port Vila, and were placed in compulsory government-mandated 14-day quarantine in 15 hotels. Pre-arrival health operations included collection of repatriate information, quarantine facility assessments, training for personnel supporting the process, and tabletop and functional exercises with live scenario simulations. During quarantine, health monitoring, mental health assessments and psychosocial support were provided. All repatriates completed 14 days of quarantine. One person developed symptoms consistent with COVID-19 during quarantine but tested negative. Overall health operations were considered a success despite logistical and resource challenges.
Lessons learnt were documented during a health sector after-action review held on 22 July 2020. Key recommendations for improvement were to obtain timely receipt of repatriate information before travel, limit the number of repatriates received and avoid the mixing of “travel cohorts”, ensure sufficient human resources are available to support operations while maintaining other essential services, establish a command and control structure for health operations, develop training packages and deliver them to all personnel supporting operations, and coordinate better with other sectors to ensure health aspects are considered. These recommendations were applied to further improve health operations for subsequent repatriation and quarantine, with Phase 2 commencing on 1 August 2020.