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991.

Background

In this study, the authors compared the odds of exposure to Legionella pneumophila among currently active dental practitioners with that of nonpractitioners and evaluated demographic and clinical practice predictors of exposure.

Methods

The authors obtained demographic characteristics and dental practice behaviors from participants in the annual American Dental Association Health Screening Program survey administered from 2002 through 2012. The authors assayed serum samples obtained from participants for L pneumophila antibodies. The authors used an adjusted logit model to evaluate predictors of positive results.

Results

Among 5,431 participants, approximately 10% were positive for L pneumophila, with no significant differences between dental practitioners and nonpractitioners. Geographic location was the only significant predictor of seropositivity, with no increased risk of being exposed to L pneumophila associated with age, race, sex, years in practice, hours of practice per week, use of barrier protection, or infection control practices.

Conclusions

Prevalence of L pneumophila antibodies was 10.4% among dental and nondental personnel. US Census division was the only significant predictor of seropositivity. The authors conclude that provision of dental care did not increase the risk of being exposed to Legionella.

Practical Implications

Dentists should be aware of the prevalence of Legionella species in their practice areas to understand their personal risk of developing an infection.  相似文献   
992.
Objective:To identify which dental and/or cephalometric variables were predictors of postretention mandibular dental arch stability in patients who underwent treatment with transpalatal arch and lip bumper during mixed dentition followed by full fixed appliances in the permanent dentition.Materials and Methods:Thirty-one patients were divided into stable and relapse groups based on the postretention presence or absence of relapse. Intercuspid, interpremolar, and intermolar widths; arch length and perimeter; crowding; and lower incisor proclination were evaluated before treatment (T0), after lip bumper treatment (T1), after fixed appliance treatment (T2), and a minimum of 3 years after removal of the full fixed appliance (T3). Logistic regression analyses were performed to evaluate the effect of changes between T0 and T1, as predictive variables, on the occurrence of relapse at T3.Results:The model explained 53.5 % of the variance in treatment stability and correctly classified 80.6 % of the sample. Of the seven prediction variables, intermolar and interpremolar changes between T0 and T1 (P = .024 and P = .034, respectively) were statistically significant. For every millimeter of increase in intermolar and interpremolar widths there was a 1.52 and 2.70 times increase, respectively, in the odds of having stability. There was also weak evidence for the effect of sex (P = .047).Conclusions:The best predictors of an average 4-year postretention mandibular dental arch stability after treatment with a lip bumper followed by full fixed appliances were intermolar and interpremolar width increases during lip bumper therapy. The amount of relapse in this crowding could be considered clinically irrelevant.  相似文献   
993.

Background

Oral squamous cell carcinoma is the most common manifestation of malignancy in the oral cavity. Adjuncts are available for clinicians to evaluate lesions that seem potentially malignant. In this systematic review, the authors summarized the available evidence on patient-important outcomes, diagnostic test accuracy (DTA), and patients’ values and preferences (PVPs) when using adjuncts for the evaluation of clinically evident lesions in the oral cavity.

Types of Studies Reviewed

The authors searched for preexisting systematic reviews and assessed their quality using the Assessing the Methodological Quality of Systematic Reviews tool. The authors updated the selected reviews and searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials and DTA and PVPs studies. Pairs of reviewers independently conducted study selection, data extraction, and assessment of the certainty in the evidence by using the Grading of Recommendations Assessment, Development and Evaluation approach.

Results

The authors identified 4 existing reviews. DTA reviews included 37 studies. The authors retrieved 7,534 records, of which 9 DTA and 10 PVPs studies were eligible. Pooled sensitivity and specificity of adjuncts ranged from 0.39 to 0.96 for the evaluation of innocuous lesions and from 0.31 to 0.95 for the evaluation of suspicious lesions. Cytologic testing used in suspicious lesions appears to have the highest accuracy among adjuncts (sensitivity, 0.92; 95% confidence interval, 0.86 to 0.98; specificity, 0.94; 95% confidence interval, 0.88 to 0.99; low-quality evidence).

Conclusions and Practical Implications

Cytologic testing appears to be the most accurate adjunct among those included in this review. The main concerns are the high rate of false-positive results and serious issues of risk of bias and indirectness of the evidence. Clinicians should remain skeptical about the potential benefit of any adjunct in clinical practice.  相似文献   
994.

Background

No evidence-based guidelines exist for preventive dental care before radiation therapy (RT) in patients with head and neck cancer (HNC). An ongoing multicenter, prospective cohort study, Clinical Registry of Dental Outcomes in Head and Neck Cancer Patients (OraRad), is addressing this knowledge gap. The authors evaluated the level of dental disease before RT in the OraRad cohort, factors associated with dental disease, and dental treatment recommendations made before RT.

Methods

As part of OraRad, the authors assessed caries, periodontal disease, dental recommendations, and dental interventions performed before RT.

Results

Baseline measures were reported for 356 participants (77% men) with mean (standard deviation) age of 59.9 (11.0) years. Measures included mean number of teeth (22.9), participants with at least 1 tooth with caries (37.2%), and participants with at least 1 tooth with probing depth 5 millimeters or greater (47.4%). Factors associated with less extensive dental disease before RT included having at least a high school diploma, having dental insurance, history of routine dental care, and a smaller tumor size (T1 or T2). Based on the dental examination before RT, 163 (49.5%) participants had dental treatment recommended before RT, with extractions recommended most frequently.

Conclusion

Many patients with HNC require dental treatment before RT; more than one-third require extractions.

Practical Implications

Most patients have some level of dental disease at the start of RT, indicating the importance of dental evaluation before RT. By observing dental outcomes after RT, OraRad has the potential to determine the best dental treatment recommendations for patients with HNC.  相似文献   
995.
996.
Background: Patients undergoing dental treatment have an uncertain understanding about dental implant therapy and its complications. Therefore, the aims of this study assess the following: 1) level of knowledge, awareness, and attitudes about peri‐implantitis; 2) information provided by dentists/specialists who perform the treatment; and 3) perceptions, level of satisfaction, and impact on patient quality of life (QoL). Methods: Patients with implant restorative therapy currently undergoing peri‐implant maintenance therapy were recruited. Participants completed an anonymous questionnaire that included general aspects of prognosis, including the following: 1) peri‐implantitis; 2) etiology; 3) awareness; 4) attitudes; 5) treatment; 6) prevention; 7) risk factors; 8) quality of information; 9) level of patient satisfaction; and 10) QoL. Associations among questionnaire data were identified using univariate and multivariate analyses. Results: Overall, 411 implants were included from 135 patients with implants. Frequency of peri‐implantitis in the survey was 17.8% at the participant level, with 70% of them reporting high level of post‐surgical satisfaction. Worry and concern were frequent findings among patients with peri‐implantitis (64%), and 32% reported that living with the disease was terrible. The vast majority of patients (74.1%) did not have knowledge about peri‐implant pathology. Patients with peri‐implantitis showed statistically significantly better understanding of implant therapy (P <0.001) and also higher average concern (P = 0.004). Conclusions: Patients generally have a poor understanding and perception of peri‐implantitis and its impact. QoL was impaired by the presence of peri‐implantitis with high level of concern and low level of therapeutic satisfaction. Therefore, it is important to develop standardized information brochures to educate patients on risk factors and indicators of the disease to assist in the prevention of peri‐implantitis.  相似文献   
997.

Statement of problem

The changes that occur after brushing yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) are unknown. These changes may favor the retention of microorganisms and chemisorption of water, impairing its longevity.

Objective

The purpose of this in vitro study was to evaluate the effects of a whitening dentifrice on Y-TZP surfaces after simulating 10 years of brushing.

Material and methods

Seventy-two bar-shaped specimens (20×4×1.2 mm) were divided into 4 groups: storage in distilled water (SW, control), brushing with distilled water (BW), brushing with dentifrice (BD), and brushing with whitening dentifrice (BWD). Brushing was conducted using a linear brushing machine (878 400 cycles, 0.98 N, soft toothbrush). The mean roughness (Ra) was analyzed with a profilometer and the superficial topography with scanning electron microscopy (SEM) at baseline and after treatment. Crystalline phases were characterized using x-ray diffraction. Baseline and posttreatment Ra were analyzed using the 1-way ANOVA and Tukey HSD multiple comparison test; the paired t test was used for intragroup comparison (all α=.05).

Results

The Ra (μm) means (before/after treatment) were SW 0.28/0.28; BW 0.32/0.31; BD 0.28/0.36; BWD 0.30/0.20. No statistically significant difference was found for Ra at baseline (P=.108) than for posttreatment results (P<.001); the BD group had higher Ra values when compared with baseline (P=.019); the BWD group had the lowest values (P<.001). The BD surfaces showed pronounced scratches and detachment of the surface, while BWD showed smoother surfaces; similar crystallographic results among groups were observed.

Conclusions

Brushing Y-TZP with conventional dentifrice increased roughness, while brushing with whitening dentifrice reduced roughness. Neither dentifrice changed the crystallographic phases after brushing.  相似文献   
998.

Statement of problem

Whether microthreads in the crestal portion can reduce the amount of marginal bone loss (MBL) around implants has not yet been determined.

Purpose

The purpose of this systematic review was to investigate the marginal bone loss around dental implants with and without microthreads in the neck.

Material and methods

This review was based on the PRISMA guidelines. An electronic search with no restrictions on language was performed from inception to August 19, 2015, in PubMed, Cochrane Central Register of Controlled Trials, EMBASE, Web of Sciences, and AMED (Ovid) databases. A manual search was also performed. Randomized clinical trials (RCTs) that compared the MBL between implants with and without microthreads in the neck were included. Qualitative synthesis and meta-analysis were performed. MBL was measured by using the mean difference (MD). Review Manager v5.3 software was used for meta-analysis (α=.05).

Results

Five articles were included in the qualitative synthesis, and 3 articles were included in the meta-analysis. Four studies found that a microthread design can significantly reduce MBL under functional loading, whereas 1 study found no signi?cant difference. The homogeneity test of meta-analysis confirmed acceptable heterogeneity among the 3 studies (I2=0.49). A random-effects model was used. The result shows that MBL around implants with microthread design can be reduced signi?cantly (P=.030; MD: ?0.09; CI: ?0.18 to ?0.01).

Conclusions

Meta-analysis showed that microthread design in the implant neck can reduce the amount of MBL; however, RCTs included in the review were few and the difference was small. In clinical practice, an implant with a roughened surface and microthreaded neck could be selected to maintain bone level.  相似文献   
999.
Background: This study aims to investigate association between peri‐implant maintenance therapy (PIMT) and the frequency of peri‐implant diseases and to further identify factors that contribute to failure of PIMT compliance. Methods: A cross‐sectional study on patients who were healthy and partially edentulous was conducted. They were grouped in the following categories according to PIMT compliance: 1) regular compliers (RC) (≥2 PIMT/year); 2) erratic compliers (EC) (<2 PIMT/year); and 3) non‐compliers (NC) (no PIMT). Radiographic and clinical analyses were carried out including probing depth (PD), plaque index (PI), bleeding on probing (BOP), mucosal redness (MR), suppuration (SUP), keratinized mucosa dimension, and marginal bone loss. A multiple logistic regression model was estimated at implant and patient level to obtain adjusted odds ratios (ORs) and to control possible confounding effects among variables. Results: Overall, 206 implants in 115 patients fulfilled inclusion criteria. At patient level, it was shown that association between compliance and peri‐implant condition was statistically significant (P = 0.04). Compliance was associated with 86% fewer conditions of peri‐implantitis. The probability of PIMT compliance was substantially associated with frequency of peri‐implantitis (OR = 0.13, P = 0.01). Patients with a history of periodontal disease multiplied their probability of being EC (versus NC) 4.23 times with respect to not having a history of periodontal disease (P = 0.02). Moreover, light smokers significantly resulted to be NC compared with RC (P = 0.04) and EC (P = 0.02). Nevertheless, mucositis was not found to be statistically associated with level of compliance. In addition, PD, PI, BOP, MR, and SUP varied significantly according to PIMT compliance and peri‐implant condition. Conclusions: Peri‐implant maintenance compliance ≥2 PIMT/year seems to be crucial to prevent peri‐implantitis in healthy patients. Furthermore, history of periodontal disease and disease severity, as well as its extent and a smoking habit, appear to be factors that influence the compliance risk profile (NCT02789306).  相似文献   
1000.
Hereditary angioedema (HAE) is a group of three uncommon and potentially fatal conditions, each of which is transmitted as a somatic dominant trait. A recognized trigger to attacks is dental treatment, with tooth extraction frequently reported in the published work. The clinical symptoms may not manifest for many hours or even days after the procedure. We describe a recent case in Australia in which death resulted from HAE following dental extraction, and we discuss its post‐mortem presentation and diagnosis, highlighting the need for dental practitioners to be aware of this condition.  相似文献   
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