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Dentistry and coronavirus (COVID-19)-moral decision-making

The coronavirus (COVID-19) has challenged health professions and systems and has evoked different speeds of reaction and types of response around the world. The role of dental professionals in preventing the transmission of COVID-19 is critically important. While all routine dental care has been suspended in countries experiencing COVID-19 disease during the period of pandemic, the need for organised urgent care delivered by teams provided with appropriate personal protective equipment takes priority. Dental professionals can also contribute to medical care. Major and rapid reorganisation of both clinical and support services is not straightforward. Dental professionals felt a moral duty to reduce routine care for fear of spreading COVID-19 among their patients and beyond, but were understandably concerned about the financial consequences. Amidst the explosion of information available online and through social media, it is difficult to identify reliable research evidence and guidance, but moral decisions must be made.

By |2020-12-18T00:09:55+00:00January 1st, 2020|Covid19|

Vitamin D Deficiency and Oral Health: A Comprehensive Review

Vitamin D (VD) levels have been gaining growing attention in Oral Health. During growth and adulthood, VD deficiency (VDD) is associated with a wide variety of oral health disorders, and impaired VD synthesis may expedite some of these conditions. In children, severe VDD can induce defective tooth mineralization, resulting in dentin and enamel defects. As a consequence, these defects may increase the risk of the onset and progression of dental caries. Further, VDD has been associated with higher prevalence of periodontitis and gingival inflammation, and several recent preclinical and clinical studies have unveiled potential pathways through which Vitamin D may interact with the periodontium. VDD correction through supplementation may contribute to a successful treatment of periodontitis; however, alveolar bone regeneration procedures performed in baseline VDD patients seem more prone to failure. Vitamin D may also be linked with some oral pathology entities such as certain oral cancers and events of osteonecrosis of the jaw. This review aims to provide comprehensive evidence of how VD levels should be considered to promote good oral health, and to summarize how VDD may hamper oral development and its role in certain oral conditions.

By |2020-12-16T00:18:58+00:00January 1st, 2020|Other|

Er: YAG Laser Irradiation Reduces Microbial Viability When Used in Combination with Irrigation with Sodium Hypochlorite, Chlorhexidine, and Hydrogen Peroxide.

The erbium-doped yttrium aluminum garnet (Er:YAG) laser is used to treat periodontal disease; however, its effectiveness at killing oral bacteria is not well known. Furthermore, the compounding effect of the combination of a laser treatment and irrigation methods with antimicrobials on bacterial viability is yet to be determined. The purpose of this in vitro study was to evaluate the effect of the Er:YAG laser with irrigation using chlorhexidine (CHX), hydrogen peroxide (H2O2), or sodium hypochlorite (NaOCl) on the viability of oral bacteria. Three bacterial species were used in our study: Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. Bacteria were grown in an anaerobic chamber in brain heart infusion broth and incubated at 37 °C. Bacterial samples with an OD of 0.5 were irradiated with the Er:YAG laser at 2940 nm using a 400-µm Varian tip. The experiment was repeated four times using these parameters: 40 mJ, 40 Hz, and 1.6 W for 20 seconds with the 300 µs short pulse duration in contact mode. Treatment groups consisted of the following: (1) no treatment, (2) 0.5% H2O2 alone, (3) 0.5% NaOCl alone, (4) 0.03% CHX alone, (5) Er:YAG irradiation alone, (6) Er:YAG irradiation with 0.5% H2O2, (7) Er:YAG irradiation with 0.5% NaOCl, and (8) Er:YAG irradiation with 0.03% CHX. Microbial viability was determined through plating and colony counts and calculated into CFU/ml. Statistical analysis was done using a two-tailed paired t-test. The use of the Er:YAG laser alone failed to show statistically significant antibacterial activity against any of bacteria. The most effective mono-treatment with irrigation solutions for all three bacteria were 0.5% H2O2 and 0.5% NaOCl (p < 0.001 for each solution). Irrigation with 0.03% CHX was most effective against F. nucleatum (p < 0.01) and less against P. gingivalis and S. gordonii and showed the least antibacterial action alone but improved significantly in combination therapy (p < 0.05). The combined treatment with the Er:YAG showed the greatest and most significant improvement in the reduction of bacterial viability compared to any other treatment group (p < 0.05 for each combined treatment). Irradiation with the Er:YAG laser with the addition of 0.5% H2O2, 0.5% NaOCl, or 0.03% CHX under a short working time (20 s) resulted in a significant reduction of bacterial viability for all three bacterial species compared with any single treatment option. The combination of irradiation with the Er:YAG laser with the addition of 0.5% H2O2, 0.5% NaOCl, or 0.03% CHX resulted in a larger reduction of bacterial survival when compared to monotherapies with antimicrobial solutions or laser. The combination of the Er:YAG laser with a low concentration irrigant solution of 0.5% H2O2, 0.5% NaOCl, or 0.03% CHX could be an effective treatment protocol for the reduction of periodontal pathogens and thus suitable treatment for non-surgical periodontal therapy.

Refractory healing after surgical therapy of osteonecrosis of the jaw: associated risk factors in aged patients.

Purpose:

Osteonecrosis of the jaw (ONJ), both medication-related and non medication-related, mainly occurs in aged patients. It needs surgical intervention. Refractory healing after an operation of ONJ can significantly lower the quality of life of elderly patients. The purpose of this study was to determine risk factors associated with refractory healing in aged patients.

Patients and methods:

We performed a retrospective study of ONJ in aged patients who underwent surgical treatments in a single institute during a 12-year period. Multiple logistic regression analysis was used to determine independent risk factors associated with refractory healing.

Results:

A total of 122 patients were included. Of them, 25 patients were identified as the refractory group and 97 patients as the control group. Diabetes mellitus (DM) (AOR=5.03, 95% CI: 1.74-14.52) and glucocorticoid administration (AOR=7.97, 95% CI: 2.52-25.23) were found to be significant risk factors for refractory healing of ONJ. Conclusion: DM and medication of glucocorticoid might be risk factors for refractory healing of ONJ.

By |2019-11-23T00:28:00+00:00January 1st, 2019|Other|

Adjunctive application of antimicrobial photodynamic therapy in the prevention of medication-related osteonecrosis of the jaw following dentoalveolar surgery: a case series.

BACKGROUND:

Medication-related osteonecrosis of the jaw (MRONJ) is a debilitating complication strongly associated to antiresorptive agents. The present study aimed to describe the use of antimicrobial photodynamic therapy (aPDT) in the prevention of MRONJ.

METHODS:

The sample consisted of 11 non-oncologic osteoporotic subjects in therapy with non-intravenous antiresorptive agents, requiring tooth extractions and/or implant removal. After minimally invasive surgical extractions, each alveolar socket was debrided and bony edges were smoothened. At this point, aPDT was performed using methylene blue-based phenothiazine chloride dye irradiated with a hand-held 100 mW diode laser with a wavelength of 660 ± 10 nm. Flaps were sutured to achieve first intention closure. Soft tissue healing was promoted with weekly applications of low-level laser therapy for 6 weeks. Recall visits were scheduled weekly for the first two months and monthly thereafter up to 6 months. At the 6-month appointment, healing was assessed clinically and radiographically.

RESULTS:

A total of 62 surgical extractions were performed in both jaws, including 51 natural elements and 11 dental implants. No intraoperative complications were observed. Immediate post-operative period was generally uneventful except for mild pain and ecchymosis that occurred rarely and resolved spontaneously. Healing proceeded uneventfully, with no clinical or radiological prodromal manifestations of MRONJ up to the latest follow-up visit.

CONCLUSIONS:

aPDT might constitute a promising preventive treatment to reduce the risk of MRONJ in non-oncologic osteoporotic patients treated with non-intravenous antiresorptive agents that underwent dentoalveolar surgery.

By |2020-01-23T01:16:25+00:00January 1st, 2019|Periodontal Disease|

Immunological Pathways Triggered by Porphyromonas gingivalis and Fusobacterium nucleatum: Therapeutic Possibilities?

Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum) are Gram-negative anaerobic bacteria possessing several virulence factors that make them potential pathogens associated with periodontal disease. Periodontal diseases are chronic inflammatory diseases of the oral cavity, including gingivitis and periodontitis. Periodontitis can lead to tooth loss and is considered one of the most prevalent diseases worldwide. P. gingivalis and F. nucleatum possess virulence factors that allow them to survive in hostile environments by selectively modulating the host’s immune-inflammatory response, thereby creating major challenges to host cell survival. Studies have demonstrated that bacterial infection and the host immune responses are involved in the induction of periodontitis. The NLRP3 inflammasome and its effector molecules (IL-1β and caspase-1) play roles in the development of periodontitis. We and others have reported that the purinergic P2X7 receptor plays a role in the modulation of periodontal disease and intracellular pathogen control. Caspase-4/5 (in humans) and caspase-11 (in mice) are important effectors for combating bacterial pathogens via mediation of cell death and IL-1β release. The exact molecular events of the host’s response to these bacteria are not fully understood. Here, we review innate and adaptive immune responses induced by P. gingivalis and F. nucleatum infections and discuss the possibility of manipulations of the immune response as therapeutic strategies. Given the global burden of periodontitis, it is important to develop therapeutic targets for the prophylaxis of periodontopathogen infections.

By |2020-01-09T02:05:53+00:00January 1st, 2019|Other|

Ultrasound Sonography to Detect Focal Osteoporotic Jawbone Marrow Defects: Clinical Comparative Study with Corresponding Hounsfield Units and RANTES/CCL5 Expression.

Introduction: The presently used impulse echo ultrasound examination is not suitable to provide relevant and reliable information about the jawbone, because ultrasound (US) almost completely reflects from the hard cortical jawbone. At the same time, “focal osteoporotic bone marrow defects” (BoneMarrowDefects = BMD) in jawbone are the subject of scientific presentations and discussions.

Purpose: Can a newly developed trans-alveolar ultrasonic sonography (TAU-n) device locate and ascertain BMD?

Patients and methods: TAU-n consists of a two-part handpiece with an extraoral ultrasound transmitter and an intraoral ultrasound receiver. The TAU-n computer display shows the different jawbone densities with corresponding colour coding. The changes in jawbone density are also displayed numerically. The validation of TAU-n readings: A usual orthopantomogram (2D-OPG) on its own is not suitable for unequivocally determining jawbone density and has to be excluded from this validation. For validation, a 3D-digital volume tomogram@/cone beam computer tomogram (DVT@/CBCT) with the capacity to measure Hounsfield units (HU) and a TAU-n are used to determine the presence of preoperative BMD in 82 patient cases. Postoperatively, histology samples and multiplex analysis of RANTES@/CCL5 (R@/C) expression derived from surgically cleaned BMD areas are evaluated.

Results: In all 82 bone samples, DVT-HU, TAU-n values and R/C expressions show the presence of BMD with chronic inflammatory character. However, five histology samples showed no evidence of BMD. All four evaluation criteria (DVT-HU, TAU-n, R/C, histology) confirm the presence of BMD in each of the 82 samples.

Conclusion: The TAU-n method almost completely matches the diagnostic reliability of the other methods. The newly developed TAU-n scanner is a reliable and radiation-free option to detect BMD.

By |2021-01-06T00:28:44+00:00January 1st, 2019|Other|

The Sixth Extinction: Vaccine Immunity and Measles Mutants in a Virgin Soil.

For more than 25 years, I have been, as a gastroenterologist, interested in inflammatory bowel disease—Crohn’s disease and ulcerative colitis—and the gut-brain connection, particularly in childhood autism. In addition, I am concerned with the environmental factors that are driving the current epidemics of both autism and inflammatory bowel disease. The issue is contentious, and one’s view depends greatly on perspective. This article provides one perspective on the delicate and often misunderstood ecological balance between man and microbe, a misunderstanding fraught with assumptions and wishful thinking.

By |2020-01-31T23:58:06+00:00January 1st, 2019|Other|

Clinical Evaluation of a Chairside Amalgam Separator to Meet Environmental Protection Agency Dental Wastewater Regulatory Compliance.

Objectives: The aim of this study was to evaluate the performance of a commercially available chairside amalgam separator (CAS) in a clinical setting in which a relatively high number of amalgam restorations are placed. Performance parameters investigated included service life, amalgam collected, mercury concentrations in effluent, and solids retention efficiency.

Methods and materials: CASs were tested per International Organization of Standardization (ISO) 11143:2008 prior to installation in a military dental treatment facility and after removal from service (n=4) in order to confirm compliance with the recently enacted United States Environmental Protection Agency (EPA) Effluent Limitations Guidelines and Standards for the Dental Category. During the units’ time in service, biweekly effluent grab samples were collected from the high-volume evacuation system of each chair (n=6) and analyzed for total mercury concentration by inductively coupled plasma mass spectrometry (ICP-MS). The mean total accumulated solids at the end of service life (n=6) was determined for potential design optimization. The service life expectancy in a military dental treatment facility was determined in terms of calendar and workdays. Procedural data were collected to determine the daily mean number of amalgam surfaces placed during the service life of each chairside amalgam separator (n=9).

Results: The CAS evaluated met minimum EPA compliance requirements when used in a military dental treatment facility. The solids removal efficiency at the end of service life was 99.82% ± 0.14% (n=4). The mean service life (n=8) was 131.6 ± 45.1 calendar days (67.1±37.6 workdays). Effluent mercury concentrations ranged from 0.05 to 11.93 mg/L. Total solids accumulated in each CAS (n=6) at the end of service life was 195.4 ± 63.4 g. The mean number of amalgam surfaces placed per workday during the service life span of each CAS was 8.4 ± 1.4.

Inflammation and Temporomandibular Joint Derangement.

Temporomandibular disorders (TMD) are a common stomatognathic disease affecting all age groups. Patients with internal derangement (ID) or osteoarthritis (OA) of temporomandibular joint (TMJ) often have TMJ synovitis. When TMJ synovial membrane is damaged, many inflammatory cytokines are produced and secreted from TMJ synoviocytes to synovial fluid of TMJ. It has been widely reported that many kinds of biologic factors are produced from TMJ synoviocytes stimulated with interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha. One of the major symptoms of TMD is pain of the TMJ. Many study groups have studied relations between the development of TMJ pain and biologic factors secreted into synovial fluid of TMJ. Here, we summarize previous reports trying to elucidate this correlation. On the other hand, it has been reported that a new molecular mechanism of IL-1beta secretion called inflammasome is involved in several diseases with sterile inflammation. Because TMJ synovitis with ID and OA of TMJ is also sterile inflammation, inflammasome may be involved in the development of TMJ synovial inflammation. This review describes some molecular mechanisms underlying inflammation in TMJ, especially in TMJ synovitis, which may be useful for the development of new therapies against TMD.

By |2020-01-07T00:06:58+00:00January 1st, 2019|Other|
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