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91.
Objectives: Several studies have described oral surgical procedures in patients receiving anticoagulant therapy, but no prospective studies on dental implant surgery during anticoagulant treatment are currently available, and only a limited number of case reports refer to endosseous dental implant treatment in these patients. In the setting of oral surgery, it has been suggested that anticoagulant treatment is not required when the International Normalized Ratio (INR) is <4 and local haemostatic measures are applied. The purpose of this preliminary study was to evaluate the incidence of bleeding complications following surgical implant therapy in a group of 50 consecutive patients receiving oral anticoagulant therapy (warfarin) without interruption or modifications to their therapy (group A). Materials and methods: One hundred and nine otherwise healthy patients comparable for age, sex, extent and site of the implant surgical procedure formed the control group (group B). In both groups, a standard protocol of local haemostasis, including non‐reabsorbable sutures and compressive gauzes soaked with tranexamic acid, was applied. Surgeons, blind to the group allocation, performed all the procedures in an outpatient setting. Results: Two and three late‐bleeding complications were reported in group A and group B, respectively, without significant difference in the bleeding risk (relative risk = 1.45; P= 0.65; 95% confidence interval 0.2506–8.4271). These complications were managed using a compressive gauze soaked with tranexamic acid at the site of the surgical wound. Conclusion: According to our preliminary results, local haemostasis in dental implant surgery is able to prevent bleeding complications in patients on oral anticoagulants, allowing these surgical procedures to be performed on an outpatient basis. To cite this article:
Bacci C, Berengo M, Favero L, Zanon E. Safety of dental implant surgery in patients undergoing anticoagulation therapy: a prospective case–control study.
Clin. Oral Impl. Res. 22 , 2011; 151–156.
doi: 10.1111/j.1600‐0501.2010.01963.x  相似文献   
92.
Evaluation of silver methenamine method for nanoleakage   总被引:1,自引:0,他引:1  
OBJECTIVES: The aim of this study was to evaluate nanoleakage patterns following silver methenamine staining of restorations bonded with a total-etch single bottle system, a self-etching primer system and a total-etch single bottle system after collagen depletion. METHODS: The dentin bonding systems used in this study were Prime and bond 2.1 (PB) and Clearfil SE Bond (CSEB). Cavities were made in grounded labial surfaces of 15 extracted bovine lower incisors, randomly divided into 3 Groups. Group 1 (PB), Group 2 (CSEB) and Group 3 (PB/SH) PB after collagen depletion with sodium hypochlorite (SH). The specimens were restored, sectioned and submitted to silver methenamine staining, polished and observed with low-vacuum back-scattered SEM. One way ANOVA and multiple-comparison Tukey's test were used for statistical analysis of the leakage scores. RESULTS: PB presented significantly greater silver deposition and a distinct pattern when compared to CSEB. No silver deposition was detected for PB after collagen depletion. SIGNIFICANCE: The dentine bonding systems tested were unable to prevent nanoleakage when used according to the manufacturers' instructions; however, CSEB presented a lower level of silver deposition. Collagen depletion prior to PB application may prevent nanoleakage occurrence in dentine walls. Silver methenamine staining may be a useful method for detection of nanoleakage in dentine when the collagen fibrils remain exposed within the hybrid layers.  相似文献   
93.
94.
The purpose of this study was to evaluate the clinical efficacy of platelet-rich plasma, autologous bone, and autologous fibrinogen as cryoprecipitate in maxillary sinus augmentation procedures. Six patients (age range, 29-58) undergoing sinus augmentation procedures were included in the study. Platelet-rich plasma and autologous fibrinogen in the form of cryoprecipitate were prepared from 300 ml of blood. Sinus augmentation was performed with intraoral bone grafts, platelet-rich plasma, and cryoprecipitate. The amount of regeneration was then evaluated quantitatively and qualitatively with Spiral TC (Dentascan) pre- and postoperatively 6 months after the intervention. Orthopantomography was performed preoperatively 3 and 6 months after the surgery. A mean platelet concentration of 320.5% was obtained from the baseline platelet blood count. The tomographic analysis indicated an average bone augmentation of 6.27 mm (range, 3.5-10 mm). Radiologically, a satisfactory morphological recovery of the maxillary jaw was obtained. No graft resorption was noticed. Orthopantomography indicated mineralization as early as 3 months postoperatively in the entire study population. This technique appeared to be safe and effective. Our preliminary results encourage the clinical use of platelet-rich plasma associated with cryoprecipitate.  相似文献   
95.
Oncogenic osteomalacia is an uncommon syndrome characterized by bone pain, proximal muscle weakness, hypophosphatemia, hyperphosphaturia, and a low plasma concentration of 1,25-dihydroxy-vitamin D. The disease affects both sexes at around 40 years of age, although it can sometimes affect children and adolescents. Generally, the syndrome is associated with a tumor, usually benign, of mesenchymal origin and is resolved after removal of the tumor; this syndrome can sometimes be associated with malignant tumors. These tumors seem to be histologically heterogeneous and are generally localized in soft tissues and bone. In this article, a case of oncogenic osteomalacia associated with a hypophosphaturic mesenchymal tumor of the ethmoid is reported in a 24-year-old man. After surgical and radical removal of the tumor, the patient noted a decrease in the clinical symptoms and signs.  相似文献   
96.
PURPOSE: To evaluate bonding penetration into different enamel substrates. MATERIALS AND METHODS: Ten extracted human molars were mesiodistally sectioned. Buccal and lingual enamel surfaces were divided into four equal areas using sticky wax. The central two areas of each tooth (n = 20) were demineralized for 12 weeks using an acidic gel (pH 4.8). The lateral areas served as controls. After demineralization, ten specimens were remineralized in a saliva substitute for three weeks. An amine fluoride solution (Elmex Fluid) was applied on one half of each specimen before acid etching. After etching for 120 s, an enamel-bonding agent (Heliobond) containing 0.1% rhodamine was applied onto test and control areas, and was light cured for 60 s. Subsequently, the specimens were sectioned and tag length was determined using a confocal laser scanning microscope (CLSM). Results were statistically compared with ANOVA followed by Scheffe's and Bonferroni/Dunn post hoc tests. RESULTS: With a mean penetration depth of 68 +/- 22 microm, tags in demineralized enamel were significantly longer than in other groups (p < or = 0.01). Penetration decreased significantly in remineralized areas or when fluoride was used (p < or = 0.01), but was still significantly deeper than in control sites (p < or = 0.01). CONCLUSION: Penetration of an unfilled resin into enamel was considerably influenced by the degree of dental hard tissue mineralization. Penetration was increased in demineralized enamel; however, remineralized enamel also allowed good penetration of the bonding agent.  相似文献   
97.
98.
Background: Plasma cell gingivitis (PCG) is a rare, benign inflammatory condition of unclear etiology with no definitive standard of care ever reported to our knowledge. The aim of this case series is to ascertain the clinical efficacy of professional oral hygiene and periodontal therapy in younger individuals with a histologically confirmed diagnosis of PCG. Methods: All patients received non‐surgical periodontal therapy, including oral hygiene instructions, and thorough supragingival scaling and polishing with the removal of all deposits and staining combined with the use of antimicrobials in a 9‐week cohort study. Clinical outcome variables were recorded at baseline and 4 weeks after the intervention and included, as periodontal parameters, full‐mouth plaque scores (FMPS), full‐mouth bleeding scores (FMBS), the clinical extension of gingival involvement, and patient‐related outcomes (visual analog score of pain). Results: A total of 11 patients (six males and five females; mean age: 11 ± 0.86 years) were recruited. Four weeks after finishing the oral hygiene and periodontal therapy protocol, a statistically significant reduction was observed for FMPS (P = 0.000), FMBS (P = 0.000), reported pain (P = 0.003) and clinical gingival involvement (P = 0.003). Conclusion: Standard, professional oral hygiene procedures and non‐surgical periodontal therapy including antimicrobials were associated with a marked improvement of clinical and patient‐related outcomes in pediatric cases of PCG.  相似文献   
99.
Low-dose methotrexate (MTX) is frequently used for patients with rheumatoid arthritis (RA). High doses of MTX frequently produce side effects. The aim of this study was to explore oral complications of low-dose MTX therapy in a population of RA patients. This is a cross-sectional study in which oral examination was performed on a population of RA patients. Patients undergoing MTX therapy (5-20 mg weekly) for at least six months were included in the study group, and RA patients being treated under another regimen were used as controls. The frequency of oral lesions was compared between groups. The chi-square test was used to compare frequencies. Relative risk (RR) and its confidence interval (CI) were established. Significance level was set at 0.05. Twenty-eight RA patients on a low-dose MTX regimen and 21 controls were enrolled in the study. Oral lesions were found in 22 patients (78.6%) undergoing MTX therapy, and in 5 patients (23.8%) undergoing other therapies (p < 0.001). There were no significant differences regarding age, gender or dosage. The most common oral events observed in patients in the MTX group were ulcerative/erosive lesions (60.7%) and candidiasis (10.7%). Patients in the control group presented lower prevalence of the same lesions (p < 0.001). The RR for developing oral lesions was 11.73 (CI 2.57 - 58.98), with low-dose MTX therapy. In conclusion, the prevalence of oral mucosa lesions in RA patients receiving low doses of MTX therapy is higher than in RA patients not receiving the drug.  相似文献   
100.
To assess the aetiology of liver disease associated with lichen planus, we prospectively studied 70 consecutive newly diagnosed patients with oral lichen planus (OLP) living in northwest Italy (Piemonte) and 70 controls matched for age and sex with other oral keratoses coming from the same district. Twenty-two patients with OLP (3.4%) and 9 controls (12.9%) were found to be affected by chronic liver disease (CLD) ( P =0.014). In sixteen of the 22 OLP patients with CLD the liver disease was hepatitis C virus (HCV)-related. whereas 2 of the 9 controls had a HCV-related CLD ( P =0.016). In another OLP case, liver damage was related to a combination of HCV and alcohol abuse. The prevalence of HCV antibodies in the whole OLP group (27.1%) was significantly higher than in controls (4.3%) ( P =0.014). whereas no difference was found between the OLP and control groups regarding hepatitis B virus markers and other common causes of CLD. HCV infection was more frequently found in patients with erosive OLP (58.8%) than in patients with non-erosive OLP (13.2%) ( P =0.004). Serum HCV-RNA was detected by polymerase chain reaction (RT-PCR) in the majority (93.7%) of OLP patients who had HCV antibodies. Excluding OLP and control patients with HCV markers, there was no difference between the two groups regarding frequency of CLD. Our data show that HCV is probably the main pathogenic factor in liver disease of Italian patients with OLP. and suggests that HCV could be involved in the pathogenesis of OLP.  相似文献   
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