抗敏感牙膏缓解牙本质敏感的临床试验研究

目的:评价有效成分为5.53%(质量分数)柠檬酸钾的抗敏感牙膏缓解牙本质敏感的效果.方法:采用随机、对照、双盲的研究方法.牙本质敏感的评价采用冷空气喷吹法,在常温下,距离牙面1 cm处气枪吹压缩空气,受试者确认是否敏感,采用数字化疼痛评判法(visual analogue scale,VAS)记录受试者的敏感程度.按照临床试验研究受试者纳入和排除标准纳入受试者.基线时纳入受试者67人,按照性别和年龄组将纳入的受试者分层随机分为试验组和对照组,试验组36人,对照组31人.试验组使用含5.53%(质量分数)柠檬酸钾的抗敏感牙膏,对照组使用空白对照牙膏,每天刷牙两次,每次至少1 min,在基线、4周、8周时分别回访受试者.结果:65名受试者完成了8周的临床试验研究,57名受试者(试验组31人,对照组26人)符合研究过程的各项要求,其资料用于结果评价.从基线到8周评价期间,试验组和对照组受试者的冷刺激敏感VAS值和主观敏感VAS值均显著减少,试验组和对照组受试者从基线到4周冷刺激敏感VAS值的变化差异有统计学意义(P<0.05),从基线到8周时主观敏感VAS值的变化在两组间差异也有统计学意义(P<0.05).结论:临床试验结果表明含有5.53%柠檬酸钾的抗敏感牙膏可有效缓解牙本质敏感.     

Dentine hypersensitivity: the effects of brushing desensitizing toothpastes, their solid and liquid phases, and detergents on dentine and acrylic: studies in vitro

Dentine exhibiting symptoms of dentine hypersensitivity has tubules open at the dentine surface and patent to the pulp. The mechanisms whereby dentinal tubules are exposed is ill understood but probably involves a variety of abrasive and/or erosive agents. This study in vitro examined the quantitative and qualitative effects of toothpastes, their solid and liquid phases and detergents on dentine and acrylic. Abrasion of dentine and acrylic were measured by surfometry. Morphological changes to dentine were assessed by scanning electron microscopy. Abrasion of dentine and acrylic by toothpastes increased with increasing brushstrokes with marked differences in the extent of abrasion between different pastes. Brushing dentine with water or detergents produced progressive abrasion but which appeared to plateau around 2 microm loss. Water and detergents produced minimal effects on acrylic. At 5000 strokes dentine abrasion by solid phases was less than the parent toothpastes but the ranking order of abrasivity was the same as the parent toothpastes. Loss of dentine produced by liquid phases was minimal and in the order of 1-2 microm. Observationally, all toothpastes removed at least the dentine smear layer to expose many tubules; with one desensitizing product leaving a particulate deposit occluding most tubules. The solid phases of the toothpaste produced identical morphological changes to the parent paste. The liquid phases and detergents all exposed dentinal tubules by 5000 strokes. Water had little or no effect on the dentine smear layer. It is concluded that toothpastes, solid phase, liquid phase and detergents have the potential to abrade or erode dentine to a variable degree and result in tubule exposure. The effects of the liquid phases and detergents appear limited to the removal of the smear layer. Such detrimental effects seen in vitro could have relevance to the aetiology and management of dentine hypersensitivity. Toothpaste formulations which despite exposing tubules have ingredients capable of occluding tubules may be an area of development for such products.     

Sore nipples in breast-feeding women: a clinical trial of wound dressings vs conventional care

BACKGROUND: Sore nipples in breast-feeding mothers are a common cause of premature weaning, and are difficult to treat owing to recurrent trauma and exposure to the infant's oral flora. OBJECTIVE: To compare the safety and efficacy of a hydrogel moist wound dressing (Elasto-gel, Southwest Technologies Inc, Baltimore, Md) with the use of breast shells and lanolin cream in the treatment of maternal sore nipples associated with breast-feeding. DESIGN: Randomized controlled trial comparing the above treatments for sore nipples. Patients were seen for a maximum of 3 follow-up visits within 10 days, or until the resolution of symptoms. SETTING: The Maternal-Infant Lactation Center at the Mercy Hospital of Pittsburgh, Pittsburgh, Pa, a tertiary care teaching hospital in inner-city Pittsburgh. PATIENTS: A referred sample of 42 breast-feeding women who presented to the Maternal-Infant Lactation Center for the treatment of sore nipples. All patients with breast infection or chronic unrelated pain conditions were excluded from the study. INTERVENTION: After informed consent, patients were randomized to receive either a hydrogel wound dressing or breast shells and lanolin. All patients underwent a history, physical examination of the infant and the mother's breasts, assessment of breast-feeding technique, and breast-feeding instruction. MAIN OUTCOME MEASURES: The degree of pain on self-report questionnaires and the change in scores for physical examination, breast-feeding technique, and pain behaviors during breast-feeding. RESULTS: Although both treatments, in association with instruction in breast-feeding technique, were effective, greater improvement was seen in the group using breast shells and lanolin. This reached statistical significance for physician-rated healing (P<.01) and self-reported pain (P<.05). There were significantly more infections in the dressing group (P<.05), which resulted in early discontinuation of the study. CONCLUSIONS: Prevention of sore nipples by teaching proper technique on the initiation of breast-feeding should be instituted. For those cases in which sore nipples do develop, breast shells and lanolin in association with instruction in breast-feeding technique are more effective than moist wound dressings. Lanolin and shells should remain first-line therapy.     

Prediction of response to treatment in a randomized clinical trial of couple therapy: A 2-year follow-up.

Many studies have examined pretreatment predictors of immediate posttreatment outcome, but few studies have examined prediction of long-term treatment response to couple therapies. Four groups of predictors (demographic, intrapersonal, communication, and other interpersonal) and 2 moderators (pretreatment severity and type of therapy) were explored as predictors of clinically significant change measured 2 years after treatment termination. Results demonstrated that power processes and expressed emotional arousal were the strongest predictors of 2-year response to treatment. Moderation analyses showed that these variables predicted differential treatment response to traditional versus integrative behavioral couple therapy and that more variables predicted 2-year response for couples who were less distressed when beginning treatment. Findings are discussed with regard to existing work on prediction of treatment response, and directions for further study are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of long-term release of fluoride by type II glass ionomer cements with a conventional hardening reaction

As a part of a fundamental investigation on the fluoride release of glass ionomer cements (GIC), this study investigates the operator dependency of the fluoride release. In this respect the GIC fluoride release of a classical powder-liquid based system (Fuji II) and a capsule-based system (Fuji Cap II) in water during 14 days was determined on the hand of 5 specimens per formulation, made by 5 different operators. The data reveal that the variance on the fluoride release as well as the mean fluoride release at a given time are independent of the operator for both Fuji II and Fuji Cap II. In order to derive fundamental factors affecting the GIC fluoride release, the long-term fluoride release of 10 conventional setting type II GIC is investigated. In this respect the fluoride release profiles (FRP) of each of 5 cylindrical specimens (d = 6 mm, h = 3 mm) of Fuji II (FP), Fuji Cap II (FC), Miracle Mix (MM), Chemfil II (CP), Chemfil II in caps. (CC), Chelon-Fil (CF), Ketac-Fil (KF), Shofu II (SH), Chelon-Silver (CS) and Ketac-Silver (KS) were determined. The specimens were made according to the manufacturer's instruction and equilibrated at 37 degrees C in 25 mL distilled water up to 140 days. The water was regularly renewed and the fluoride concentration [F] of the equilibrated solution determined. A Multivariate Data Analysis of the ?[F]],t?-profiles on the basis of Principal Component Analysis (PCA) reveals that the FRP can be classified into 4 distinct groups: ?CS,KS,FP? - ?FC,CC? - ?CF,KF? and ?MM?, leaving SH and CP apart as unclassifiable. When the cumulative amount of fluoride released ([F]c) for each individual sample is calculated and fitted as a function of time, a regression analysis shows that [F]c is most adequately fitted (r > 0.99) by [F]c = [F]I/t + t1/2 + beta. Square root of t, indicating that 2 kinetic processes are responsible for the FRP. A comparison of the parameters of this equation ([F]I, t1/2 and beta) shows that the physicochemical rationale for this classification of the GIC conforms to differences in the kinetics of these processes. From the classification, it becomes apparent that different formulations can result in the same FRP.     

Chronic hypersensitivity lung disease with recurrent episodes of hypersensitivity pneumonitis due to a contaminated central humidifer

A child with a 4-year history of acute and chronic respiratory symptoms of unknown aetiology was investigated for hypersensitivity pneumonitis. Lung disease due to inhalation of material from a contaminated central humidifier was suggested by the clinical history, the presence of precipitating antibodies in the serum against the humidifier water, a pulmonary response to challenge with the humidifier water, and marked improvement after removal of the humidifier. No fungi were cultured from the humidifier nor were antibodies against a number of fungal antigens identified by radioimmunoassay inhibition techniques. Antigenic material was found in the humidifier water and the household water prior to its reaching the humidifier. This antigenic material was not found in laboratory tap water supplied from the same general source (Lake Michigan) but from a different pumping station. Three of the child's siblings gave histories suggestive of a single concurrent episode of acute hypersensitivity pneumonitis and one sibling had a history suggestive of chronic hypersensitivity lung disease. No association could be found between HLA-haplotypy and disease in the patient and the siblings.     

A short-term clinical study design to investigate the chemical plaque inhibitory properties of mouthrinses when used as adjuncts to toothpastes: applied to chlorhexidine

The removal of plaque by toothbrushing with toothpaste is the most common form of plaque control in the developed world. However, the use of chemical adjuncts such as mouthrinses is increasing. In practice mouthrinses and toothpaste are used together, however, in many clinical trials, employed to assess mouthrinse activity, toothpaste use is suspended. This fails to measure the effect of chemical interactions which are known to occur between toothpaste ingredients and mouthrinses. The objective of this trial was to develop a methodology which would assess the adjunctive chemical plaque inhibitory action of mouthrinses, when used with toothpaste but without the indeterminate variable of toothbrushing. The study was a single blind, randomised, 7-way crossover design, based on a variation of a 4 day plaque regrowth model. The 2 x daily rinsing regimens produced increasing plaque scores in the following order: (1) water/chlorhexidine, (2) chlorhexidine/water, (3) chlorhexidine/toothpaste slurry, (4) toothpaste slurry/chlorhexidine, (5) water/toothpaste slurry, (6) toothpaste slurry/water, (7) water/water. Chlorhexidine and water or chlorhexidine and toothpaste slurry combinations produced significantly lower plaque scores than water alone. Slurry and water combinations resulted in less plaque than water alone, but differences were not significant. Toothpaste slurry and chlorhexidine produced significantly increased plaque scores compared to chlorhexidine and water. The study suggests that, outside the Hawthorne effect, chlorhexidine rinses would be less effective in reducing plaque when used with toothpaste than when used alone. The methodology could be employed as a screening tool for the evaluation of mouthrinses expected to be used as adjuncts to normal oral hygiene methods. The same could be used to optimise oral hygiene regimens which include the use of mouthrinses.     

What happens with patients after participation in a clinical trial?

107 patients with primary hypercholesterolaemia participated for five years in a clinical trial with dietary and drug treatment (a statin) at the Lipid Clinic. At the end of the study the patients were referred back to their own physicians, with written advice on diet and drug therapy. At a recall two years later we studied to what extent recommended therapy and follow-up had been implemented. 15% had no follow-up after participating in the study and 18% had not measured their cholesterol for one year or more. The majority of the patients did not follow the recommended diet and level of physical activity satisfactorily, and 20% had stopped their lipid-lowering medication. In general they had been prescribed too low doses of the lipid-lowering agent, and 70% of the patients had not reached the target of the LDL-cholesterol. In conclusion, adequate treatment and a five-year follow-up is not sufficient to keep the patient compliant when the follow-up becomes less intensive. When a clinical trial is terminated, greater efforts should be made to secure better compliance to therapy.     

Megestrol acetate for anorexia in patients with far-advanced cancer: a double-blind controlled clinical trial

The aim of this study was to evaluate a low-dose regimen of megestrol acetate (MA; 320 mg/day) on appetite in advanced cancer patients. Out-patients with far-advanced non-hormone responsive tumours and loss of appetite were randomised in a phase III trial, with two consecutive phases: a 14-day double-blind placebo controlled phase (phase A) and a 76-day open phase (phase B). During phase A, patients were treated with MA, two 160 mg tablets/day, or placebo. In phase B, the MA dose was titrated to clinical response in both groups. Appetite, food intake, body weight, performance status, mood and quality of life were evaluated with standardised measures; patients' global judgement about treatment efficacy was also requested. Of 42 patients entering the study, 33 (17 MA and 16 placebo) were evaluable for efficacy. The appetite score improved significantly with MA after 7 days (P = 0.0023), and this effect was still significant at 14 days (P = 0.0064). Patients judged the treatment with MA effective in 88.2% of cases (14th day), whilst placebo was considered effective by 25% (P = 0.0003). None of the other measures showed significant changes during treatment. The remarkable effect on appetite evident after 7 days, without serious side-effects, shows that MA can produce significant subjective effects at a low-dose even in patients with far-advanced disease.     

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part I: Methodology and clinical outcomes

STATEMENT OF PROBLEM: Scientific evidence is lacking to support the general application of implant-supported mandibular overdentures. PURPOSE: This randomized clinical trial was undertaken to compare the efficacy of conventional mandibular and implant-supported overdentures in diabetic edentulous patients with clinically acceptable metabolic control. METHOD: A total of 102 diabetic patients, treated with or without insulin, were randomized to receive a new maxillary denture and either a conventional or an implant-supported removable mandibular overdenture. Treatment was completed for 89 patients, 37 with the conventional and 52 with implant-supported dentures. Detailed examinations, tests, and questionnaires were given before and at 6- and 24-months after treatment completion. Comparisons between the two treatment groups were made for treatment failures based on prespecifed criteria and the type and amount of maintenance care provided. RESULTS: The insulin and noninsulin treated groups were collapsed because of the lack of significant differences at entry. The conventional denture and implant-supported overdenture groups were similar in terms of general demographics, medical status, quality of their original dentures and denture support, several functional measures, and patient satisfaction. Treatment was judged to be successful in 56.9% of patients with conventional dentures and 72.1% with overdentures. This difference in success rate was not statistically significant (p > 0.05). Patients with treatment failures in both groups required excessive maintenance care. Those with conventional dentures needed frequent denture base adjustments and relines, whereas those with overdentures required frequent clip replacements and repairs. Although significant improvements were seen with both treatment modalities, a higher percentage of patients with implant-supported overdentures than those with conventional dentures reported improvements in chewing comfort and moderate-to-complete overall satisfaction.     

Effectiveness of an ambulatory care clinical pharmacist: a controlled trial

Medical therapy for duodenal or gastric ulcer disease has traditionally involved gastric acid antisecretory therapy for 4 to 8 weeks to promote initial healing and indefinitely to prevent recurrences of ulcer. The discovery of Helicobacter pylori in most patients with peptic ulcer disease has led to a change in this approach. Therapy designed to eradicate H pylori may facilitate ulcer healing with acid antisecretory agents and, more important, may greatly reduce the incidence of ulcer recurrence, obviating the need for maintenance antisecretory therapy. Regimens designed to eradicate H pylori are difficult to comply with, however, and are associated with adverse effects in some patients. In this article we review the diagnosis and treatment of H pylori infection in patients with peptic ulcer disease and make recommendations regarding the use of conventional ulcer therapies and therapies designed to eradicate H pylori.     

Complex retinal detachment treated with silicone oil or sulfur hexafluoride gas: a randomized clinical trial

BACKGROUND AND OBJECTIVE: To determine if either silicone oil or sulfur hexafluoride gas (SF6) is superior to the other in the treatment of complex retinal detachment after previously failed vitreous surgery. PATIENTS AND METHODS: In this randomized clinical trial, 18 patients received treatment with silicone oil and 16 patients received SF6. The primary outcome was defined as successful anatomic attachment of the retina. Secondary outcomes included the time to retinal detachment, visual acuity, anatomic macular attachment, and any complications of surgery. RESULTS: The odds of successful reattachment with silicone oil were 50% greater than they were with SF6, but this difference was not statistically significant. There were no differences between the two groups in any of the secondary outcomes. CONCLUSIONS: This study did not have enough statistical power to detect a small but clinically important difference between the two treatment groups. Physicians must use their clinical judgment to select a vitreal substitute for complex retinal detachment when clinical trials are inconclusive. Data pooling is one method of overcoming the limitation of clinical trials with small sample sizes.     

Independence and statistical inference in clinical trial designs: a tutorial review

The identification of the proliferative activity in tumours may be useful to predict the biological behaviour of different lesions. Proliferating cell nuclear antigen (PCNA) has been used for the evaluation of the proliferative ability of many lesions. In this study 22 ameloblastomas (4 follicular, 5 plexiform, 4 acanthomatous, 5 unicystic, 4 recurrent), 12 odontogenic keratocysts (OKC), 8 dentigerous cysts (DC), and 12 radicular cysts (RC) were analysed. PCNA+ cells were present in all cyst types but the OKC contained the highest number of PCNA+ cells. In OKC the location of PCNA+ cells was mainly suprabasal. In ameloblastoma PCNA+ cells were located mainly in the peripheral portion of the tumour islands. Statistical analysis showed that ameloblastoma had higher PCNA+ cell counts than OKC (P < 0.0001); OKC had higher values than DC and RC (P < 0.0001). Recurrent ameloblastoma presented higher PCNA+ cell counts than other types of ameloblastoma, while unicystic ameloblastoma showed lower values than acanthomatous, plexiform and follicular ameloblastomas (in this latter case the difference was not statistically significant). These data could help to explain the different biological behaviour of these lesions.     

Laparoscopic transperitoneal versus extraperitoneal inguinal hernia repair: a prospective clinical trial

Myoporum laetum was collected in the municipalities of Rio Grande and Capao do Leao in winter and in Santa Vitoria in summer, autumn, winter and spring, in the state of Rio Grande do Sul, Brazil, and in the Department of Rocha, Uruguay, in winter and spring. The fresh green plant was fed to 17 sheep. All sheep developed clinical signs, except 1 that consumed only 4 g/kg bw daily during 10 d. Five of the 9 sheep dosed with 40 g/kg died. Four sheep dosed with plants from Uruguay at 40 g/kg, 6 sheep dosed with 20 g/kg, and 1 sheep dosed with 2 daily doses of 8 g/kg survived. Clinical signs were anorexia, restlessness, ruminal stasis, jaundice and dry feces with mucus or blood. All surviving sheep had photodermatitis in the face, ears, eyes and lips. Histologic lesions were characterized by periportal liver necrosis. Serum levels of AST, GGT and bilirubin were increased. M laetum from Uruguay was less toxic, suggesting a variation in toxicity among plants from different regions.     

Applying k-sample tests to conditional probabilities for competing risks in a clinical trial

In the presence of competing risks, a full picture of the data can be developed considering the cumulative incidence function for each risk. If one risk type is of particular interest, the conditional probability of failure due to that risk, conditional on no failure due to the remaining competing risks, can be used to compare any number of samples. Kappa-sample tests of significance are derived and extended to stratified test statistics, allowing adjustment to be made for important prognostic factors. The methods are applied to a clinical trial involving patients with advanced breast cancer, where interest focused on progression of disease at old and new sites. They show that estrogen receptor status positive is an important prognostic factor in terms of time to progressive disease at a current tumour site, even when stratified for a potentially confounding measure of spread of disease, whereas progesterone receptor status positive is important with regard to disease progression at new sites only.     

Prevention of respiratory complications after abdominal surgery: a randomised clinical trial

OBJECTIVE: To evaluate the prevention of respiratory complications after abdominal surgery by a comparison of a global policy of incentive spirometry with a regimen consisting of deep breathing exercises for low risk patients and incentive spirometry plus physiotherapy for high risk patients. DESIGN: Stratified randomised trial. SETTING: General surgical service of an urban teaching hospital. PATIENTS: 456 patients undergoing abdominal surgery. Patients less than 60 years of age with an American Society of Anesthesia classification of 1 were considered to be at low risk. OUTCOME MEASURES: Respiratory complications were defined as clinical features consistent with collapse or consolidation, a temperature above 38 degrees C, plus either confirmatory chest radiology or positive results on sputum microbiology. We also recorded the time that staff devoted to prophylactic respiratory therapy. RESULTS: There was good baseline equivalence between the groups. The incidence of respiratory complications was 15% (35/231) for patients in the incentive spirometry group and 12% (28/225) for patients in the mixed therapy group (P = 0.40; 95% confidence interval -3.6% to 9.0%). It required similar amounts of staff time to provide incentive spirometry and deep breathing exercises for low risk patients. The inclusion of physiotherapy for high risk patients, however, resulted in the utilisation of an extra 30 minutes of staff time per patient. CONCLUSIONS: When the use of resources is taken into account, the most efficient regimen of prophylaxis against respiratory complications after abdominal surgery is deep breathing exercises for low risk patients and incentive spirometry for high risk patients.