不同排牙方法对全口义齿咀嚼效能的影响

目的:探讨不同排牙法的全口义齿咀嚼效能的异同。方法:采用上颌排牙法、下颌排牙法和综合排牙法为10名无牙颌患者分别制作3副全口义齿。戴用3个月后,通过吸光度法测定咀嚼效率,比较不同排牙法的全口义齿咀嚼效能的异同,并与有牙颌进行对比。结果:在单侧咀嚼和双侧咀嚼2种咀嚼方式下,全口义齿患者的咀嚼次数和咀嚼效能均少于有牙颌组,本实验3组全口义齿在3个月后均发挥了良好的咀嚼效能。下颌排牙法和综合排牙法全口义齿的咀嚼次数和咀嚼效能无统计学差异,但均好于上颌排牙法全口义齿。结论:下颌排牙法和综合排牙法的全口义齿排列的人工牙能够减少在咀嚼过程中不利于全口义齿稳定因素的影响,提高咀嚼效能。     

Relationship between attitudes toward oral health at initial office visit and compliance with supportive periodontal treatment

OBJECTIVES: The objectives of the present study include investigation of the relationship between attitudes and desires with respect to oral health at initial office visit and compliance with supportive periodontal treatment (SPT) and identification of prognostic factors with respect to low-compliance with SPT. MATERIALS AND METHODS: Four hundred thirty-one patients were evaluated. Subjects completed a questionnaire concerning attitude and desire with respect to oral health and subjective symptoms prior to periodontal treatment. Survival probabilities of SPT were estimated by the Kaplan-Meier method and compared between answers for each item of the questionnaire via the Cox-Mantel test. Finally, a multivariate Cox proportional hazards regression model was constructed, which included age and gender. RESULTS: Greater than 95% of participants desired toothbrushing proficiency and lifelong retention of teeth at the initial office visit; however, the overall survival probabilities of SPT were only 52.7% after about 5 years. Patients exhibiting unfavourable attitudes toward oral health at the initial office visit, in comparison with those displaying favourable attitudes, exhibited greater tendency to abandon SPT. A Cox regression model revealed that lack of brushing on the gingival margin, non-use of an inter-dental brush or dental floss, non-use of fluoride toothpaste and frequent consumption of sugar-containing drinks were significant independent prognostic factors for low-compliance with SPT (p<0.05; Hazard ratios=2.27, 2.00, 2.56 and 2.06, respectively). CONCLUSIONS: Desire for satisfactory oral health is not related consistently to continuation of SPT. Unfavourable attitudes toward oral health were correlated to low-compliance with SPT. Clinicians may wish to establish methods for improvement of patient compliance employing behavioural approaches applicable to the attitudes of potential low-compliance individuals.     

羟基磷灰石涂层热处理晶化工艺研究

目的：通过热处理方法提高羟基磷灰石（HA）涂层的结晶度、使脱落的羟基得到恢复。方法：通过等离子喷涂和热处理试验，利用X射线衍射（XRD）和红外吸收光普分析等手段研究了热处理对羟基磷石涂层相组成的影响。结果：热处理可使涂层中的非晶相发生晶化，并使羟基得到恢复；随着热处理温度的提高，涂层的结晶度提高，α－TCP等热分解相逐步转变为羟基磷灰石。保温时间达到2小时后，延长保温时间并不能提高涂层的结晶工。结论：在大气环境下，涂层的最佳热处理工艺是在700℃下保温2小时。     

The burden of restorative dental treatment for children in Third World countries

OBJECTIVE: To analyse whether developing countries have sufficient health dollars to treat existing diseases in general and dental caries in particular in their child population. METHODS: Assessments of the costs of treating existing and future caries by the conventional approach. Analysis of WHO dental databases and spreadsheet calculations of costs based upon population projections, prevalence and trends in patterns of caries. FINDINGS: Even though the caries levels are low and most of the disease occurs on the occlusal and the buccal/lingual surfaces, more than 90% of the dental caries remains untreated in Third World countries. Calculations reveal that to restore the permanent dentition of the child population of low-income nations using traditional amalgam restorative dentistry would cost between pounds 1,024 ($US1618) and pounds 2,224 ($US3513) per 1,000 children of mixed ages from 6 to 18 years. This exceeds the available resources for the provision of an essential public health care package for the children of 15 to 29 low-income countries. CONCLUSIONS: To treat caries with the traditional method of restorative dentistry is beyond the financial capabilities of the majority of low-income nations, as three-quarters of these countries do not even have sufficient resources to finance an essential package of health care services for their children.     

Matrix metalloproteinase-8 (MMP-8) in pulpal and periapical inflammation and periapical root-canal exudates

AIM: To study the presence, levels and molecular forms of matrix metalloproteinase (MMP) -8 (collage-nase-2) in pulpal and periapical inflammation, and the changes in MMP-8 levels in root-canal exudates during root-canal treatment. METHODOLOGY: Periapical exudate samples were collected from 11 necrotic teeth with radiographically verified periapical periodontitis during three root-canal treatment visits with interappointment calcium hydroxide (Ca(OH)2) medication. MMP-8 levels and molecular forms were analyzed with immunofluorescent assay (IFMA) and Western immunoblot. Inflamed pulp tissue and periapical granuloma tissue (n = 10 for both) were obtained from other patients and used for MMP-8 immunohistochemical (IHC) staining. RESULTS: The periapical exudate samples demonstrated marked differences in MMP-8 levels between the teeth in the first visit and significant decrease in MMP-8 levels during the root-canal treatment (P = 0.0107). One specimen failed to show a decrease in MMP-8 below 1000 ng mL(-1) a vertical root fracture was later diagnosed and the tooth extracted. IHC staining showed that in addition to PMN-leucocytes, macrophages and plasma cells produced MMP-8 in pulp and periapical granulomas. CONCLUSIONS: The findings demonstrate the presence of MMP-8 in the inflamed pulp and periapical tissue, indicating that MMP-8 has a role in pulpal and periapical inflammation, most likely participating in tissue extracellular matrix degradation. They further indicate that MMP analysis from periapical exudate could be used to indicate and monitor inflammatory activity and the success of treatment in teeth with periapical lesions.     

An audit of root canal treatment performed by undergraduate students

AIM: The objective of this study was to audit the quality of root canal treatment performed by undergraduate students on adult patients. METHODOLOGY: All root canal treatment completed by first and second clinical year undergraduates over a 12-month period were included in the study. The availability and readability of pretreatment, diagnostic length, try-in point and postoperative radiographs were noted for each case. All readable postoperative radiographs of primary treatments were examined for quality of the root filling, categorized as complete, incomplete apical, incomplete apical and lateral or not assessable. The distance from the radiographic apex of the root to the apical extent of each root filling was measured to 0.1 mm precision. RESULTS: Undergraduates performed primary treatment on 157 teeth. A postoperative radiograph was available in 97% of cases. A try-in point radiograph was unavailable in one-fifth of cases. Twenty-seven teeth (13%) were categorized as satisfactory in terms of both radiographic quality and distance of the root filling from the radiographic apex. CONCLUSIONS: Overall, the technical quality of root canal treatment completed by undergraduate students was poor.     

Is ART really atraumatic?

Atraumatic restorative treatment (ART) is an approach to the management of carious lesions that uses only hand instruments to remove carious tissue and to restore the tooth involved. The name ART implies that the approach is atraumatic to both the patient and the tooth. This study set out to evaluate whether ART is atraumatic in terms of both patient discomfort and tooth tissue conservation. Three hundred and fifty-nine patients were divided in two groups: one group was treated with hand instruments and the other with rotary equipment. Each patient received two restorations: one using amalgam and one using glass ionomer as the restorative material, placed without the use of anaesthesia. Less discomfort was reported with the ART approach compared to conventional restorations made using rotary instruments and amalgam. Moreover, preparations with hand instruments were smaller than those produced with rotary instruments. Reported discomfort was associated with the size of the preparation, although the influence of the operator on both criteria was considerable. A patient effect was also observed since patients who reported discomfort during the first treatment were more likely to report discomfort after the second treatment. In conclusion, the choice of the term "ART" as an atraumatic procedure is defensible.     

感官分析法和便携式硫化物检测仪检测口臭的相关性研究

目的比较感官分析法(鼻测法)和便携式硫化物检测仪(商品名Halimeter)检测口臭之间的准确性和一致性。方法首先对2名嗅辨员进行嗅觉检测试验,以确定其进行感官分析评分的资质。选择86例符合试验条件的受试者,分别用感官分析法评价口臭程度,硫化物检测仪检测口腔挥发性硫化物(VSC)含量,使用SPSS11.0软件分析鼻测法得分均值和VSC水平的关系。结果2名嗅辨员一致性良好,Kappa值达到0.568,P<0.01。鼻测法得分均值与Halimeter检测所得硫化物峰值之间相关系数r=0.538,P<0.01;与硫化物稳定值之间相关系数r=0.546,P<0.01。结论鼻测法得分和Halimeter检测的口腔VSC含量之间存在显著相关关系,提示Halimeter可在一定程度上作为鼻测法的辅助手段,用以检测口臭。     

A clinical study evaluating the treatment of supra-alveolar-type defects with access flap surgery with and without an enamel matrix protein derivative: a pilot study

Aim: There is evidence that regenerative treatment of intra-bony and mandibular class II furcation defects with access flap and an application of an enamel matrix protein derivative (EMD) can result in a clinical benefit compared with access flap alone. The aim of this pilot study was to check if the results of access flap surgery in suprabony defects are improved by additional application of EMD.
Material and Methods: Thirty-nine adult subjects with supra-alveolar-type defects were randomly assigned to a test ( n =25) and a control group ( n =14). Seventy teeth were treated with EMD; 28 teeth were treated by access flap. Probing depth (PD), clinical attachment level and bleeding on probing were evaluated at baseline and after 12 months.
Results: PD of the operated teeth was improved in both groups ( p <0.001 to p =0.041) but always better in the test group. The attachment gain was 2.72±1.80 mm at sites with an initial PD 7 mm in the test group and 0.78±0.62 mm in the control group ( p =0.004). In the test group the mean attachment gain was 0.97±0.92 mm ( p <0.001); the mean reduction of PD was 1.55±0.90 mm ( p <0.001).
Conclusions: The data suggest a significant clinical benefit of supplementary application of EMD during surgical treatment of periodontitis of supra-alveolar pockets, especially in deeper pockets.