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991.
992.
993.
This study investigated the prevalence of dental caries and periodontal condition in a population with sickle cell disease (SCD), analyzing some associations with disease severity. The Decayed, Missing and Filled Teeth index (DMFT) and Community Periodontal Index (CPI) were recorded for 99 individuals with SCD and 91 matched controls. Socio-demographic status, oral health behaviors, and history of clinical severity of SCD were assessed. Statistical comparisons were performed between the group with SCD and the control group, as well as multivariate logistic regression analyses with DMFT index and CPI as the dependent variables. The mean number of decayed teeth was significantly higher in individuals with HbSS. Older age, female gender, and daily smoking were identified as risk factors for higher DMFT, while older age and absence of daily use of dental floss were risk factors for the development of periodontal disease. In conclusion, risk factors known to cause caries and periodontal disease had more influence on oral health than the direct impact of SCD.  相似文献   
994.
To investigate change in oral health in relation to use of dental services, a random sample of 45‐ to 54‐yr‐old subjects from Adelaide, South Australia, was surveyed in 2004–2005 (= 986, response rate = 44.4%). Service use and a global oral‐health transition (GOHT) statement were collected over 2 yr. Worsening in oral health was reported from the GOHT statement by 25% of persons, while improvement was reported by 30%. Prevalence ratios (PRs, 95% CI), adjusted for sex, education, health card status, and toothbrushing, showed that worsening oral health was inversely associated with dental visiting (PR = 0.5, 0.4–0.7) and with scaling and cleaning services (PR = 0.6, 0.4–0.9), whereas extractions (PR = 2.3, 1.6–3.4) and dentures (PR = 2.2, 1.3–3.7) were associated with a higher prevalence of worsening. Scaling and cleaning services were associated with improvement in oral health (PR = 1.5, 1.01–2.3), while endodontic services were inversely associated with improvement (PR = 0.3, 0.1–0.9). Worsening in oral health was associated with extractions and dentures and was inversely associated with visiting and preventive care. Improvement in oral health was associated with preventive care and was inversely associated with endodontic treatment.  相似文献   
995.
Introduction and Aim: The term osseoperception describes the capability of developing a subtle tactile sensibility over dental implants. The present clinical study aims at clarifying the question of how far tactile sensibility is to be attributed to the periodontium of the natural opposing tooth of the implant. Material and Method: Thirty‐two subjects with single‐tooth implants with natural opposing teeth were included in this clinical, single‐blind, split‐mouth study. The natural antagonistic tooth of the implant and the corresponding natural contralateral tooth were anesthetized with a locally infiltrated articaine anesthetic. In a computer‐assisted and randomized way, copper foils of varying thickness (0–100 µm) were placed interocclusally between the single‐tooth implant and the natural opposing tooth, and between the contralateral pair of natural opposing teeth in order to investigate the active tactile sensibility according to the psychophysical method of constant stimuli and evaluate it statistically by the Weibull distribution. Results: The average tactile sensibility of the implants with anesthetized antagonists at the 50% value calculated by means of the Weibull distribution was 20 ± 11 µm with a support area (90%–10% value) of 77 ± 89 µm. For the pair of natural teeth, the tactile sensibility at the 50% value was 16 ± 9 µm with a support area of 48.4 ± 93 µm. This resulted in an average intraindividual difference of 3.5 ± 7 µm at the 50% value and 29 ± 93 µm in the support area. The statistical calculations demonstrated an equivalent tactile sensibility (50% value) of the single‐tooth implant and the contralateral natural control tooth with the natural antagonists being anesthetized in each case (double t‐test, equivalence limit ± 8 µm, P < 0.01, power >80%). Conclusion: Apparently, the active tactile sensibility of single‐tooth implants with natural opposing teeth is not only to be attributed to the periodontium of the opposing tooth but also to a perception over the implant itself. This could support the hypothesis according to which the implant may have a tactile sensibility of its own.  相似文献   
996.
Background: Insufficient alveolar bone height often prevents the placement of standard dental implants in the posterior part of edentulous maxilla. In order to increase adequately the vertical dimension of the reabsorbed alveolar process, a sinus lift procedure is often necessary. The aim of this study was to evaluate histologic results of a prehydrated corticocancellous porcine bone used in maxillary sinus augmentation. Methods: Patients (age 18–70 years) with a residual bone height requiring a maxillary sinus augmentation procedure to place dental implants were eligible for this study. All patients were treated with the same surgical technique consisting of sinus floor augmentation via a lateral approach. The space obtained by elevation of the mucosa wall was grafted with prehydrated and collagenated corticocancellous porcine bone. Biopsies were harvested 6 months after the augmentation procedures. Results: Twenty‐four patients were enrolled. The mean percentage of new formed bone was 43.9 ± 18.6% (range 7.5–100%), whereas the mean percentage of residual graft material was 14.2 ± 13.6% (range 0–41.9%). The new bone/residual graft material ratio in the maxillary sinuses was 3.1. The mean soft tissues percentage was 41.8 ± 22.7% (range 0–92.5%). Conclusion: The present study suggested that porcine bone showed excellent osteoconductive properties and could be used successfully for sinus augmentation. Moreover, the porcine bone showed a high percentage of reabsorption after 6 months; this might be because of the presence of collagen and the porosity of the graft material.  相似文献   
997.
Objective: To systematically assess the informational value, quality, intention, source and bias of web 2.0 footage whose aim is peer‐to‐peer education about oral implantology. Methods: YouTube ( http://www.youtube.com ) was scanned on 15 October 2010 for oral implantology‐related videos using an adequately pre‐defined search query. Search results were filtered with the system‐generated category ‘education’ and the additional criterion ‘most viewed’. Only those videos with at least 1000 views were included (total 124, of which 27 were excluded because they were not related to implantology). Filtered videos were discussed and rated with particular regard to the educational needs of potential groups of addressees [(i) undergraduates and laymen, (ii) dentists without or currently undergoing a specialisation in oral implantology and (iii) dentists who have completed a specialisation in the field of oral implantology] by a jury consisting of (i) an accredited post‐graduate university instructor with 22 years of professional teaching experience in the field of implantology, (ii) a university lecturer in dentistry/orthodontics with 10 years teaching experience and (iii) a university haematologist/oncologist. They were required to fill out a questionnaire for each video. The data were statistically analysed using non‐parametric ANOVA (α = 5%) and a sign test (α = 0.05/3 = 0.017). Results: The YouTube scan produced 1710 results in the category ‘EDU’. The analysis revealed that there is a wide range of instructional footage on this topic, but with highly variable range in quality and informational value. Footage intention was to large proportions (47.4%) a mixture of education and advertisement. Its usefulness differed significantly for the three groups of addressees, offering greater novelty to undergraduates and post‐graduates. Conclusion: YouTube and similar social media websites may have a potential capacity and value in complementing continuing education in the technique of oral implantology. As a means of achieving an acceptable level of knowledge about the topic when used alone, it should not be considered to be suitable at this point in time.  相似文献   
998.
999.
Objectives: This study assessed the reliability and validity of the Child Oral Health Impact Profile–Short Form 19 (COHIP‐SF 19) from the validated 34‐item COHIP. Methods: Participants included 205 pediatric, 107 orthodontic, and 863 patients with craniofacial anomalies (CFAs). Item level evaluations included examining content overlap, distributional properties, and use of the response set. Confirmatory factor analysis identified potential items for deletion. Scale reliability was assessed with Cronbach's alpha. Discriminant validity of the COHIP‐SF 19 was evaluated as follows: among pediatric participants, scores were compared with varying amounts of decayed and filled surfaces (DFS) and presence of caries on permanent teeth; for orthodontic patients, scores were correlated with anterior tooth spacing/crowding; and for those with CFA, scores were compared with clinicians' ratings of extent of defect (EOD) for nose and lip and/or speech hypernasality. Convergent validity was assessed by examining the partial Spearman correlation between the COHIP scores and a standard Global Health self‐rating. Comparisons between the COHIP and the COHIP‐SF 19 were completed across samples. Results: The reduced questionnaire consists of 19 items: Oral Health (five items), Functional Well‐Being (four items), and a combined subscale named Socio‐Emotional Well‐Being (10 items). Internal reliability is ≥0.82 for the three samples. Results demonstrate that the COHIP‐SF 19 discriminates within and across treatment groups by EOD and within a community‐based pediatric sample. The measure is associated with the Global Health rating (P < 0.05), thereby indicating convergent validity. Conclusions: Reliability and validity testing demonstrate that the COHIP‐SF 19 is a psychometrically sound instrument to measure oral health‐related quality of life across school‐aged pediatric populations.  相似文献   
1000.
During infection, interactions between Candida albicans and oral epithelial cells result in oral epithelial cell death. This is clinically manifested by the development of oral mucosal ulcerations generally associated with discomfort. In vitro studies have shown that C. albicans induces early apoptotic alterations in oral epithelial cells; however, these studies have also shown that treatment of infected cells with caspase inhibitors does not prevent their death. The reasons for these contradictory results are unknown and it is still not clear if C. albicans stimulates oral epithelial signaling pathways that promote apoptotic cell death. Activation of specific death pathways in response to microbial organisms plays an essential role in modulating the pathogenesis of a variety of infectious diseases. The aim of this study was to (i) characterize C. albicans‐induced apoptotic morphological alterations in oral epithelial cells, and (ii) investigate the activation of apoptotic signaling pathways and expression of apoptotic genes during infection. Candida albicans induced early apoptotic changes in over 50% of oral epithelial cells. However, only 15% of those showed mid‐late apoptotic alterations. At the molecular level, C. albicans caused a loss of the mitochondrial transmembrane potential and translocation of mitochondrial cytochrome c. Caspase‐3/9 activities increased only during the first hours of infection. Moreover, poly[ADP ribose] polymerase 1 was cleaved into apoptotic and necrotic‐like fragments. Finally, five anti‐apoptotic genes were significantly upregulated and two pro‐apoptotic genes were downregulated during infection. Altogether, these findings indicate that epithelial apoptotic pathways are activated in response to C. albicans, but fail to progress and promote apoptotic cell death.  相似文献   
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