Periodontitis: A Plausible Modifiable Risk Factor for Neurodegenerative Diseases? A Comprehensive Review.

The aim of this comprehensive review is to summarize recent literature on associations between periodontitis and neurodegenerative diseases, explore the bidirectionality and provide insights into the plausible pathogenesis. For this purpose, systematic reviews and meta-analyses from PubMed, Medline and EMBASE were considered. Out of 33 retrieved papers, 6 articles complying with the inclusion criteria were selected and discussed. Additional relevant papers for bidirectionality and pathogenesis were included. Results show an association between periodontitis and Alzheimer's disease, with odds ratios of 3 to 5. A bidirectional relationship is suspected. For Parkinson's disease (PD), current evidence for an association appears to be weak, although poor oral health and PD seem to be correlated. A huge knowledge gap was identified. The plausible mechanistic link for the association between periodontitis and neurodegenerative diseases is the interplay between periodontal inflammation and neuroinflammation. Three pathways are hypothesized in the literature, i.e., humoral, neuronal and cellular, with a clear role of periodontal pathogens, such as Porphyromonas gingivalis. Age, gender, race, smoking, alcohol intake, nutrition, physical activity, socioeconomic status, stress, medical comorbidities and genetics were identified as common risk factors for periodontitis and neurodegenerative diseases. Future research with main emphasis on the collaboration between neurologists and dentists is encouraged.

The predictive value of masticatory function for adverse health outcomes in older adults: a systematic review.

Masticatory function is associated with a variety of health outcomes. The aim of this systematic review is to clarify the predictive value of masticatory function for adverse health outcomes, such as frailty, sarcopenia and malnutrition, in older adults. An online literature search covered articles published in English or Dutch in three databases (PubMed, Embase and CINAHL, last searched November 4th 2022). Inclusion criteria were: an observational study design, focus on adults aged ≥65 years and evaluation of the association between masticatory function and health outcomes. Reviews and articles published before the year 2000 were excluded. Methodological quality and risk of bias were assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the U.S. National Institutes of Health. Study population demographics, methods for assessing masticatory function, and the association between masticatory function and adverse health outcomes were extracted. From the 34 included studies, 5 studies had a prospective design, 2 had a retrospective design, and the other 27 studies had cross-sectional design. The majority of the studies were conducted in Japan (74%, n = 26). Twenty studies (59%) used one indicator for masticatory function, the other 41% used two (n = 9) or more (n = 5) indicators. Masticatory function was most frequently assessed with the maximum occlusal force (MOF) (79%, n = 27). The identified health outcomes were clustered into 6 categories: physical parameters and sarcopenia, history of falling, nutritional status, frailty, cognitive function and mortality. Despite the complex and multidimensional character of both masticatory function and most identified adverse health outcomes, some significant associations were reported. Prospective studies showed that reduced masticatory function in older adults is associated with incidence of frailty and frailty progression, cognitive decline and all-cause mortality. Regarding the other identified adverse health outcomes, i.e., physical measures and sarcopenia, history of falling and nutritional status, only cross-sectional studies were available and results were less concordant. As all prospective studies showed that reduced masticatory function in older adults is associated with adverse health outcomes, prevention of decline of masticatory function by adequate oral care may contribute to healthy ageing.

Predictive factors for the treatment success of peri-implantitis: a protocol for a prospective cohort study.

INTRODUCTION: Peri-implantitis, a common biological complication of dental implant, has attracted considerable attention due to its increasing prevalence and limited treatment efficacy. Previous studies have reported several risk factors associated with the onset of peri-implantitis (eg, history of periodontitis, poor plaque control and smoking). However, inadequate data are available on the association between these risk factors and successful outcome after peri-implantitis therapy. This prospective cohort study aims to identify the local and systemic predictive factors for the treatment success of peri-implantitis. METHODS AND ANALYSIS: A single-centre cohort study will be conducted by recruiting 275 patients diagnosed with peri-implantitis. Sociodemographic variables, healthy lifestyles and systemic disorders will be obtained using questionnaires. In addition, clinical and radiographic examinations will be conducted at baseline and follow-up visits. Treatment success is defined as no bleeding on probing on more than one point, no suppuration, no further marginal bone loss (≥0.5 mm) and probing pocket depth ≤5 mm at the 12-month follow-up interval. After adjustment for age, sex and socioeconomic status, potential prognostic factors related to treatment success will be identified using multivariable logistic regression models. ETHICS AND DISSEMINATION: This cohort study in its current version (2.0, 15 July 2022) is in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital, Southern Medical University (EC-CT-(2022)34). The publication will be on behalf of the study site. TRIAL REGISTRATION NUMBER: ChiCTR2200066262.

Towards an operational definition of oral frailty: A e-Delphi study.

OBJECTIVES: Building upon our recently developed conceptual definition of oral frailty (the age-related functional decline of orofacial structures), this e-Delphi study aims to develop an operational definition of oral frailty by identifying its components. METHODS: We used a modified e-Delphi study to reach a consensus among international experts on the components of oral frailty. Twelve out of fifteen invited experts in the field of gerodontology participated. Experts responded to three rounds of an online 5-point scale questionnaire of components to be included or excluded from the operational definition of oral frailty. After each round, scores and rationales were shared with all experts, after which they could revise their position. A consensus was reached when at least 70% of the experts agreed on whether or not a component should be included in the operational definition of oral frailty. RESULTS: The experts achieved a high level of agreement (80 - 100%) on including eight components of oral frailty and excluding nineteen. The operational definition of oral frailty should include the following components: 1) difficulty eating hard or tough foods, 2) inability to chew all types of foods, 3) decreased ability to swallow solid foods, 4) decreased ability to swallow liquids, 5) overall poor swallowing function, 6) impaired tongue movement, 7) speech or phonatory disorders, and 8) hyposalivation or xerostomia. CONCLUSION: This e-Delphi study provided eight components that make up the operational definition of oral frailty. These components are the foundation for the next stage, which involves developing an oral frailty assessment tool.

Development of a pharmacokinetic and pharmacodynamic model for intranasal administration of midazolam in older adults: a single-site two-period crossover study.

BACKGROUND: Intranasal midazolam can produce procedural sedation in frail older patients with dementia who are unable to tolerate necessary medical or dental procedures during domiciliary medical care. Little is known about the pharmacokinetics and pharmacodynamics of intranasal midazolam in older (>65 yr old) people. The aim of this study was to understand the pharmacokinetic/pharmacodynamic properties of intranasal midazolam in older people with the primary goal of developing a pharmacokinetic/pharmacodynamic model to facilitate safer domiciliary sedation care. METHODS: We recruited 12 volunteers: ASA physical status 1-2, aged 65-80 yr, and received midazolam 5 mg intravenously and 5 mg intranasally on two study days separated by a 6 day washout period. Concentrations of venous midazolam and 1'-OH-midazolam, Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score, bispectral index (BIS), arterial pressure, ECG, and respiratory parameters were measured for 10 h. RESULTS: Time to peak effect of intranasal midazolam for BIS, MAP, and SpO2 were 31.9 (6.2), 41.0 (7.6), and 23.1 (3.0) min, respectively. Intranasal bioavailability was lower compared with intravenous administration (Fabs 95%; 95% confidence interval: 89-100%). A three-compartment model best described midazolam pharmacokinetics following intranasal administration. A separate effect compartment linked to the dose compartment best described an observed time-varying drug-effect difference between intranasal and intravenous midazolam, suggesting direct nose-to-brain transport. CONCLUSIONS: Intranasal bioavailability was high and sedation onset was rapid, with maximum sedative effects after 32 min. We developed a pharmacokinetic/pharmacodynamic model for intranasal midazolam for older persons and an online tool to simulate changes in MOAA/S, BIS, MAP, and SpO2 after single and additional intranasal boluses. CLINICAL TRIAL REGISTRATION: EudraCT (2019-004806-90).

Decision-Making concerning Involuntary Oral Care for Older Individuals with Dementia.

Many older individuals with dementia (OIWD) show care-resistant behavior for oral care. Providing care despite resistance is considered to be involuntary care. Although involuntary care should be minimized, in some OIWD it may be necessary to avoid health risks. This study aims to assess the attitudes of healthcare providers with regard to involuntary oral care provision for OIWD who show care-resistant behavior. An online questionnaire consisting of general questions and case specific questions was administered via social media and networking to individuals involved in the oral care of OIWD. A total of 309 participants were included in this study. The outcomes of the questionnaires were categorized per case. In all cases, a discrepancy was seen between the assessment of oral health problems as potentially harmful (range: 73.1-93.5%) and the willingness to provide involuntary care (range: 31.1-63.4%). Hence, many healthcare providers are aware of the subsequent potential health risks related to not providing care, but are still reluctant to provide involuntary oral care. Therefore, many OIWD who show care-resistant behavior potentially do not receive the necessary oral care they require.

Denture wearing status, cardiovascular health profiles, and mortality in edentulous patients: A prospective study with a 27-year follow-up.

OBJECTIVES: Life's Simple 7 (LS7) metrics provide insight into improving cardiovascular health (CVH) and help reduce mortality risks. Edentulous older adults have a higher mortality risk than dentulous ones, probably due to worse oral function. It is reported that wearing dentures will decrease the mortality risk factor by improving oral function. This prospective study aimed to investigate if denture wearing could modify the association between CVH profile and mortality risk among edentulous elderly. METHODS: From the Third National Health and Nutrition Examination Survey (NHANES III), 1,735 edentulous older adults (mean age 69.4 years old) with CVH profiles and data on denture wearing status were selected for this study. CVH profiles according to LS7 metrics were classified into poor, intermediate, or ideal. Denture wearers were defined as those wearing complete dentures in both arches all the time or only when awake. Multivariable Cox proportional-hazards regression was conducted to estimate the association of CVH profiles with all-cause and cardiovascular mortality. Stratified analyses and the testing of interaction terms were used to evaluate the difference between the association in edentulous patients with and without dentures. RESULTS: A total of 1,420 (81.8%) older adults died during the 27-year follow-up, with 478 (27.6%) cases attributable to heart disease. After controlling for potential confounders, edentulous patients with an ideal CVH (LS7 = 10-14) had a lower mortality risk than those with poor CVH (LS7 = 0-4). Furthermore, we observed an effect modification by denture use (Pinteraction = 0.046), with the role of ideal CVH in mitigating mortality among the denture wearers (Hazard Ratio = 0.440 [0.329-0.588]), while no significant association among those without dentures. Similar results were achieved for cardiovascular mortality, but there was no effect modification of denture use (Pinteraction = 0.352). CONCLUSION: In this study, a favorable cardiovascular health profile presents a protective effect on all-cause mortality only among edentulous patients wearing dentures instead of non-wearer. CLINICAL SIGNIFICANCE: Denture usage could improve oral function (e.g., chewing, smiling, speaking, etc.) and promote general health. Effect modification found in this study indicates having ideal CVH alone cannot substantially reduce mortality risk among edentulous patients. Therefore, health care professionals should keep an eye on the elderly not wearing dentures as they are probably more at risk for adverse health outcomes. It remains unclear if denture wearing has a causal relation with lower mortality risks, and further research is needed.

Outcome of implants placed to retain craniofacial prostheses - A retrospective cohort study with a follow-up of up to 30 years.

OBJECTIVES: To retrospectively assess the treatment outcomes of endosseous implants placed to retain craniofacial prostheses. MATERIAL AND METHODS: Patients with craniofacial defects resulting from congenital disease, trauma, or oncologic treatment had implant retained prostheses placed in the mastoid, orbital, or nasal region and then assessed over a period of up to 30 years. Implant survival rates were calculated with the Kaplan-Meier method. Clinical assessments consisted of scoring skin reactions under the prosthesis and the peri-implant skin reactions. Possible risk factors for implant loss were identified. Patient satisfaction was evaluated using a 10-point VAS-scale. RESULTS: A total of 525 implants placed in 201 patients were included. The median follow up was 71 months (IQR 28-174 months). Implants placed in the mastoid and nasal region showed the highest overall implant survival rates (10-year implant survival rates of 93.7% and 92.5%, respectively), while the orbital implants had the lowest overall survival rate (84.2%). Radiotherapy was a significant risk factor for implant loss (HR 3.14, p < 0.001). No differences in implant loss were found between pre- and post-operative radiotherapy (p = 0.89). Soft tissue problems were not frequently encountered, and the patients were highly satisfied with their implant-retained prosthesis. CONCLUSION: Implants used to retain craniofacial prostheses have high survival and patient satisfaction rates and can thus be considered as a predictable treatment option. Radiation is the most important risk factor for implant loss.

Association between Masseter Muscle Area and Thickness and Outcome after Carotid Endarterectomy: A Retrospective Cohort Study.

Low muscle mass is associated with adverse outcomes after surgery. This study examined whether facial muscles, such as the masseter muscle, could be used as a proxy for generalized low muscle mass and could be associated with deviant outcomes after carotid endarterectomy (CEA). As a part of the Vascular Ageing study, patients with an available preoperative CT-scan, who underwent an elective CEA between December 2009 and May 2018, were included. Bilateral masseter muscle area and thickness were measured on preoperative CT scans. A masseter muscle area or thickness of one standard deviation below the sex-based mean was considered low masseter muscle area (LMA) or low masseter muscle thickness (LMT). Of the 123 included patients (73.3% men; mean age 68 (9.7) years), 22 (17.9%) patients had LMA, and 18 (14.6%) patients had LMT. A total of 41 (33.3%) patients had a complicated postoperative course and median length of hospital stay was four (4-5) days. Recurrent stroke within 5 years occurred in eight (6.6%) patients. Univariable analysis showed an association between LMA, complications and prolonged hospital stay. LMT was associated with a prolonged hospital stay (OR 8.78 [1.15-66.85]; p = 0.036) and recurrent stroke within 5 years (HR 12.40 [1.83-84.09]; p = 0.010) in multivariable logistic regression analysis. Masseter muscle might be useful in preoperative risk assessment for adverse short- and long-term postoperative outcomes.

[Why physicians should pay attention to oral health too]. / Kijk ook eens in de mond van uw patiënt.

In literature oral health is broadly described and interrelations between oral health, general health and quality of life have been established. However, oral health is often overlooked by medical professionals, in contrast to veterinarians, who inspect the mouth of their patients as a standard procedure. In this manuscript the authors explain why patients could benefit if medical professionals pay more attention to oral health, by trying to inspire them to assess oral health as part of general health and to cooperate more with dental professionals to safeguard (oral) health.

Periodontitis and cognitive impairment in older adults: The mediating role of mitochondrial dysfunction.

BACKGROUND: Increased attention has been focused on the associations of periodontal disease with the onset and progression of cognitive impairment. Although the associations are likely to be multifactorial, few studies have explored the role of mitochondrial dysfunction in the periodontitis-dementia link. METHODS: Cross-sectional data of 1,883 participants aged ≥60 years in the National Health and Nutrition Examination Survey 2011-2014 were analyzed. The following data were collected: 1) general information on sociodemographic, behavioral, and health-related factors; 2) periodontal status (mean attachment loss [AL] and mean probing depth [PD]); 3) mitochondrion-derived biomarker of mitochondrial dysfunction (blood sample concentration of methylmalonic acid [MMA]); 4) cognitive function (Consortium to Establish a Registry for Alzheimer's disease immediate recall [CERAD-IR] and delay recall [CERAD-DR], animal fluency test, and digit symbol substitution test [DSST]). Mediation analysis weighted for complex survey design was used to assess the effect of MMA on the association of periodontal status with cognitive function after adjusting for potential confounders. RESULTS: Participants with Stage III and IV periodontitis had lower scores on cognitive performance and higher MMA levels than those with Stages I/II periodontitis. Circulating MMA was significantly associated with CERAD-DR (weighted ß [SE] = -0.076 [0.011]) and DSST (weighted ß [SE] = -0.039 [0.009]), which mediated 9.9% and 6.0% of the total association of mean PD with cognitive function. Moreover, MMA mediated 11.7% and 5.8% of the association of mean AL with CERAD-DR and DSST, respectively. CONCLUSION: The findings suggest that MMA, a biomarker of mitochondrial dysfunction, plays a mediating role in the link between periodontitis and cognitive impairment in older adults aged ≥60 years.

Combined association of cognitive impairment and poor oral health on mortality risk in older adults: Results from the NHANES with 15 years of follow-up.

BACKGROUND: Cognitive impairment and poor oral health are frequently seen among older adults. Both conditions have been identified as risk factors for mortality. However, the combined associations of cognitive impairment and poor oral health with mortality have not been well studied and are therefore the aim of this cohort study. METHODS: We analyzed data from the National Health and Nutrition Examination Survey (1999-2002) linked with mortality data obtained from the 2015 public-use linked mortality file. Cognitive impairment was defined as a digit symbol substitution test score lower than the lowest quartile. Oral health status was assessed based on presence of untreated caries, moderate to severe periodontitis, and edentulism. The combined effects of caries/periodontitis or edentulism and cognitive impairment on all-cause and cardiometabolic mortality were examined using the Cox proportional hazard models after adjusting for potential confounders including demographic characteristics, lifestyle, biomarkers, and comorbidities. RESULTS: In total, 1973 participants were enrolled in the prospective study. At a median follow-up of 13.4 years, 978 participants had died (264 deaths because of cardiometabolic disease). Cognitive impairment, periodontitis, and edentulism were each found to be significant predictors of all-cause mortality. Caries, however, was not significantly related to mortality. When analyzing these predictors in combination, a diagnosis of cognitive impairment and periodontitis was associated with an 83.1% increase in all-cause mortality risk and an 87.7% increase in cardiometabolic mortality risk compared with healthy controls. Similarly, the risk for all-cause mortality was highest in cases where impaired cognition and edentulism co-occurred (adjusted hazard ratio = 1.701, 1.338-2.161). CONCLUSION: Concomitant presence of cognitive impairment and periodontitis or edentulism can be associated with a higher risk of mortality among older U.S. adults.

Intranasal midazolam for the sedation of geriatric patients with care-resistant behaviour during essential dental treatment: An observational study.

OBJECTIVES: To describe the efficacy and safety of intranasal midazolam for sedation during essential dental treatment of geriatric patients with major neurocognitive disorder (MND) and care-resistant behaviour (CRB). BACKGROUND: Dental treatment is often impossible in geriatric MND patients with CRB. Intranasal midazolam may provide a non-invasive sedation method, but there is currently no information on its use in geriatric patients. METHODS: In this observational study, we included geriatric patients with severe MND and CRB needing urgent dental treatment. Each patient received 5 mg midazolam intranasally. Agitation/sedation levels, heart rate, respiration rate and oxygen saturation were recorded at 5-minute intervals. RESULTS: Thirty two patients were included. Mean age was 84 (±7) years. Mean (SD) time to treatment start was 13 (±5) minutes, and mean time to maximum sedation 17 (±11) minutes. Sedation was sufficient to enable dental treatment to be completed in 31 (97%) patients. Anxiolysis/light sedation occurred in 16 (50%) patients, and moderate to deep sedation occurred in 16 (50%) patients. No patients suffered from apnoea, although 3 patients required a chin-lift manoeuvre. Hypoxaemia occurred in 1 of these patients and in 2 other patients without airway obstruction. All patients recovered uneventfully. In a regression model, age, weight and other sedative medication use were found not to be associated with maximum sedation depth. CONCLUSIONS: Of 5 mg intranasal midazolam facilitates treatment of geriatric patients with MND in the comfort of their own environment. More information is needed to guide titration to balance the desired sedation level and patient safety.

General health, healthcare costs and dental care use of elderly with a natural dentition, implant-retained overdenture or conventional denture: an 8-year cohort of Dutch elderly (aged 75 and over).

BACKGROUND: Cross-sectional studies have shown that elderly with a natural dentition have better general health than edentulous elderly, but this has not been confirmed in studies with longitudinal design. METHODS: This prospective longitudinal study with a follow-up of 8 years aimed to assess differences in general health, healthcare costs and dental care use between elderly with a natural dentition and edentulous elderly wearing implant-retained or conventional dentures. Based on data of all national insurance claims for dental and medical care from Dutch elderly (aged ≥75 years) general health outcomes (chronic conditions, medication use), healthcare costs and dental care use could be assessed of three groups of elderly, viz. elderly with a natural dentition, elderly with conventional dentures and elderly with implant-retained overdentures. RESULTS: At baseline (2009), a total of 168,122 elderly could be included (143,199 natural dentition, 18,420 conventional dentures, 6503 implant-retained overdentures). Here we showed that after 8 years follow-up elderly with a natural dentition had more favorable general health outcomes (fewer chronic conditions, less medication use), lower healthcare costs and lower dental costs - but higher dental care use - than edentulous elderly. At baseline the general health of elderly with an implant-retained overdentures resembled the profile of elderly with a natural dentition, but over time their general health problems became comparable to elderly with conventional dentures. CONCLUSIONS: It was concluded that elderly with a natural dentition had significant better health and lower healthcare costs compared to edentulous elderly (with or without dental implants).

When should root remnants and unrestorable broken teeth be extracted in frail older adults?

BACKGROUND: Many frail older adults have an unhealthy dentition; unrestorable broken teeth and root remnants with open root canals, commonly accompanied by periapical and periodontal inflammation, are often seen. Improving oral health in the growing group of frail older adults with remaining teeth is a considerable challenge for dental care professionals. Dentists are often uncertain how to deal with root remnants and unrestorable broken teeth in frail older adults. METHODS: The authors aim was to provide recommendations to dentists to help in their clinical decision making about the extraction or retention of roots remnants and broken teeth in frail older adults. CONCLUSIONS: Decisions about the extraction or retention of root remnants should made on the basis of preventing pain and oral discomfort, preventing severe inflammation, and preventing additional decline in oral health. Both root-related and patient-related factors are considered. PRACTICAL IMPLICATIONS: Decision-making trees can help dentists decide whether to extract root remnants and unrestorable broken teeth in frail older adults.

Candida Biofilm Formation Assay on Essential Oil Coated Silicone Rubber.

Development of biofilm associated candidemia for patients with implanted biomaterials causes an urgency to develop antimicrobial and biofilm inhibitive coatings in the management of recalcitrant Candida infections. Recently, there is an increase in the number of patients with biofilm formation and resistance to antifungal therapy. Therefore, there is a growing interest to use essential oils as coating agents in order to prevent biomaterial-associated Candida infections. Often high costs, complicated and laborious technologies are used for both applying the coating and determination of the antibiofilm effects hampering a rapid screening of essential oils. In order to determine biofilm formation of Candida on essential oil coated surfaces easier, cheaper and faster, we developed an essential oil (lemongrass oil) coated surface (silicone-rubber) by using a hypromellose ointment/essential oil mixture. Furthermore, we modified the "crystal violet binding assay" to quantify the biofilm mass of Candida biofilm formed on the lemongrass oil coated silicone rubber surface. The essential oil coating and the biomass determination of biofilms on silicone rubber can be easily applied with simple and accessible equipment, and will therefore provide rapid information about whether or not a particular essential oil is antiseptic, also when it is used as a coating agent.

General health status of Dutch elderly receiving implant-retained overdentures: A 9-year big data cross-sectional study.

BACKGROUND: Very little information is available on the general health of elderly who are provided with an implant-retained overdenture (IOD). PURPOSE: The general health status of three groups of elderly (≥75 years) were compared: those with a natural dentition (ND), those treated with an implant-retained overdenture (IOD), and those wearing a conventional denture (CD). MATERIALS AND METHODS: Data on healthcare costs were obtained from records of Dutch health insurers that are collected by Vektis. Data on general health (chronic diseases, medication use, and polypharmacy) were acquired for elderly patients with a ND, an IOD, and a CD in 2009 and 2017. Data on the general health of elderly who received an IOD were also acquired from 2010 through 2016. RESULTS: On average, the general health of elderly who received an IOD was comparable to general health of elderly with a ND and was better than the general health of elderly with a CD (lower prevalence of diabetes, cardiac disease, and hypertension). The general health profile of elderly receiving an IOD was consistent during all years. CONCLUSIONS: The general health of elderly with a ND or IODs is better than those with CDs.

Intranasal dexmedetomidine in elderly subjects with or without beta blockade: a randomised double-blind single-ascending-dose cohort study.

BACKGROUND: The aim of this double-blind, placebo-controlled, single-ascending-dose study was to determine the safety and tolerability of intranasal dexmedetomidine in the elderly. METHODS: We randomly assigned 48 surgical patients ≥65 yr of age to receive single intranasal doses of dexmedetomidine or placebo (5:1 ratio) in four sequential dose cohorts: 0.5, 1.0, 1.5, and 2.0 µg kg-1. Each dose cohort comprised two groups of six subjects: a group of subjects using ß-blockers and a group not taking ß-blockers. Vital signs and sedation depth (Modified Observer's Assessment of Alertness and Sedation [MOAA/S] and bispectral index) were measured for 2 h after administration. Blood samples were taken to determine dexmedetomidine plasma concentrations. RESULTS: One subject (1.0 µg kg-1) had acute hypotension requiring ephedrine. Systolic arterial BP decreased >30% in 15 of 40 subjects (37.5%) receiving dexmedetomidine, lasting longer than 5 min in 11 subjects (27.5%). The MAP decreased >30% (>5 min) in 10%, 20%, 50%, and 30% of subjects receiving dexmedetomidine 0.5, 1.0, 1.5, and 2.0 µg kg-1, respectively, irrespective of ß-blocker use. HR decreased 10-26%. MOAA/S score ≤3 occurred in 18 (45%) subjects; eight (20%) subjects receiving dexmedetomidine showed no signs of sedation. Tmax was 70 min. Cmax was between 0.15 ng ml-1 (0.5 µg kg-1) and 0.46 ng ml-1 (2.0 µg kg-1). CONCLUSIONS: Intranasal dexmedetomidine in elderly subjects had a sedative effect, but caused a high incidence of profound and sustained hypotension irrespective of ß-blocker use. The technique is unsuitable for routine clinical use. CLINICAL TRIAL REGISTRATION: NTR5513 (The Netherlands Trial Registry 5513).

Antifungal and biofilm inhibitory effect of Cymbopogon citratus (lemongrass) essential oil on biofilm forming by Candida tropicalis isolates; an in vitro study.

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon citratus (lemongrass) essential oil has been widely used as a traditional medicine and is well known for antimicrobial properties. Therefore, it might be a potent anti-infective and biofilm inhibitive against Candida tropicalis infections. Until now, no ideal coating or cleaning method based on an essential oil has been described to prevent biofilm formation of Candida strains on silicone rubber maxillofacial prostheses, voice prostheses and medical devices susceptible to C. tropicalis infections. AIM OF THE STUDY: To investigate the antifungal and biofilm inhibitory effects of Cymbopogon citratus oil. Clinical isolates of C. tropicalis biofilms on different biomaterials were used to study the inhibitory effect. MATERIALS AND METHODS: The efficacy of Cymbopogon citratus, Cuminum cyminum, Citrus limon and Cinnamomum verum essential oils were compared on biofilm formation of three C. tropicalis isolates on 24 well polystyrene plates. C. citratus oil coated silicone rubber surfaces were prepared using hypromellose ointment as a vehicle. The antifungal tests to determine minimum inhibitory and minimum fungicidal concentrations were assessed by a microbroth dilution method and biofilm formation was determined by a crystal violet binding assay. RESULTS: C. tropicalis strains formed more biofilm on hydrophobic materials than on hydrophilic glass. C. citratus oil showed a high antifungal effect against all C. tropicalis strains. For comparison, C. limon oil and C. cyminum oil showed minor to no killing effect against the C. tropicalis strains. C. citratus oil had the lowest minimal inhibitory concentration of all essential oils tested and inhibited biofilm formation of all C. tropicalis strains. C. citratus oil coating on silicone rubber resulted in a 45-76% reduction in biofilm formation of all C. tropicalis strains. CONCLUSION: Cymbopogon citratus oil has good potential to be used as an antifungal and antibiofilm agent on silicone rubber prostheses and medical devices on which C. tropicalis biofilms pose a serious risk for skin infections and may cause a shorter lifespan of the prosthesis.

Bar-clip versus magnet-retained auricular prostheses: A prospective clinical study with a 3-year follow-up.

STATEMENT OF PROBLEM: Implant-retained auricular prostheses, on a bar-clip or with a magnetic retention system, are considered successful treatment for missing ears. However, which of these 2 retention systems is preferred by patients is unknown. PURPOSE: The purpose of this clinical study was to assess which retention system is mostly preferred by patients wearing implant-retained auricular prostheses: bar-clip retention or magnetic retention. MATERIAL AND METHODS: All consecutive patients visiting the clinic between March 2014 and November 2014 for a routine follow-up of their implant-retained auricular prostheses on a bar-clip retention system were asked to enroll in this descriptive study comparing patient preference for the retention system: bar-clip versus magnets. Participants were asked to complete a questionnaire to obtain patient satisfaction scores regarding their auricular prosthesis before and 3 months after changing to a magnetic-retained auricular prosthesis. After 3 months, participants were asked to state their preference for either their previous bar-clip system or the new magnetic system. If they did not prefer the magnetic system, participants were able to return to their previous bar-clip system. The study follow-ups were performed at 6, 12, 24, and 36 months. Again, patient satisfaction was scored with the aid of the same questionnaire, and prosthetic care and aftercare were also assessed. RESULTS: Of 20 eligible patients, 17 participants (12 men, 5 women) enrolled in the study. The mean score for patient satisfaction for the bar-clip system at the start of the study was high (8 ±1.62). After 3 months, 2 participants wanted to return to their previous bar-clip system, followed by 1 more at the 6-month evaluation and 2 more at the 1-year evaluation. After 3 years, 9 of 16 participants (57%) preferred the magnetic-retained auricular prosthesis. During the 3 years of follow-up, aftercare was considered minor for both the bar-clip and the magnetic system. No participants developed peri-implantitis. All participants indicated that cleaning and placing the magnetic-retained auricular prosthesis was easier than the bar-clip system. CONCLUSIONS: The majority of the participants (59%) in this study, especially the elderly participants, preferred the magnetic retention system. When compared with the bar-clip system, no additional aftercare was needed.