Loss of attachment adjacent to class II carious lesions

The present study was designed to investigate the relationship between large open class II carious lesions and loss of periodontal attachment in 224 extracted teeth. Each tooth had a carious and a sound approximal surface. The teeth were divided into 4 groups: upper premolars, upper molars, lower premolars and lower molars each consisting of 56 teeth. Within each group, the carious lesions were divided equally between the mesial and distal surfaces. The teeth were stained and loss of attachment was measured under a stereomicroscope fitted with an ocularmicrometer. The difference in loss of attachment between carious (0.79 +/- 0.05 mm) and sound (0.76 +/- 0.04 mm) surfaces was not statistically significant. Loss of attachment was greater on the carious surface of 98 teeth, equal to in 40 teeth and less in 86 teeth than the sound surface. Mesial and distal surfaces with and without carious lesions exhibited essentially the same degree of loss of periodontal support. Upper molars and lower premolars tended towards more loss of attachment when compared with upper premolars and lower molars. The results indicate that large open class II carious lesions cannot be regarded as an important factor in the progression of attachment loss.     

Clinical investigation of G‐Bond resin‐based adhesive to non‐carious cervical lesions over five years

Background: The aim of this study was to evaluate the clinical performance of G‐Bond all‐in‐one adhesive with Gradia Direct resin composite placed in non‐carious cervical lesions (NCCLs) over a five‐year period. Methods: Forty‐seven restorations were placed in NCCLs in 10 subjects (age 45–75 years) after written informed consent was obtained. Institutional ethical approval for the trial was obtained before recruitment. Restorations were placed according to the manufacturer’s instructions and using 50% phosphoric acid to etch uncut enamel margins. Patients were recalled annually for five years and restorations reviewed for presence and marginal staining. Photographic records were obtained prior to restoration, immediately after placement and at each recall. Results: At five years, 6 of the original 10 subjects were available for recall, meaning 27 restoration sites could be evaluated. All restorations remained intact apart for one partial failure at four years. This resulted in a cumulative retention rate of 97.5% of restorations at five years. Marginal staining occurred around seven restorations during the study. Staining tended to be isolated to a few patients. Conclusions: It was concluded that G‐Bond with Gradia Direct resin composite showed excellent results over the five years of the study. This material combination seems very suitable for the restoration of NCCLs.     

Clinical features and factors associated with non‐carious cervical lesions and dentin hypersensitivity

Determining the factors associated with NCCLs and DH in populations could guide the implementation of specific preventive measures. This study evaluated the clinical features and factors associated with non‐carious cervical lesions (NCCLs) and dentin hypersensitivity (DH) in a Brazilian population. The participants were 118 patients at the Dentistry Clinic of our dental school. They completed an interview to obtain personal information and determine the possible factors associated with NCCLs and DH. Clinical examination was undertaken to record the NCCLs, shape of the lesion and certain occlusal factors. DH was diagnosed by air and probe tests. Data were analysed with the multilevel Poisson regression and prevalence ratios, and the respective 95% confidence intervals were calculated. The prevalence of NCCLs and DH among patients was 67·8% and 51·7%, respectively. Of a total number of 2902 teeth examined, 9·65% had NCCLs and 5·82% were sensitive to air. The most affected teeth for both conditions were the premolars. Most of the NCCLs were wedge‐shaped and located in the maxilla. The factors associated with NCCLs and DH were age and presence of premature occlusal contacts. NCCLs were also significantly associated with consumption of wine and alcoholic beverages, and DH with consumption of acidic fruits and juices. NCCLs were a common finding, with higher frequency in more advanced age groups, the maxilla and premolars. A significant association occurred between NCCLs, premature contacts and consumption of wine and alcoholic beverages. DH was associated with NCCLs, premature contacts and with the consumption of acidic fruits and juices.     

A cross‐sectional study: non‐carious cervical lesions,cervical dentine hypersensitivity and related risk factors

The present survey aims to study the prevalence and clinical characteristics of non‐carious cervical lesions (NCCLs) and cervical dentine hypersensitivity (CDH), as well as their possible risk factors in a general population in China. A total of 1023 subjects were included in the present study. Each subject completed a structured interview, and all teeth of each subject were examined by a practitioner to determine NCCLs and CDH. Teeth with NCCLs and CDH were diagnosed according to the tooth wear index and by a blast of air from a triple syringe, respectively. Binary logistic regression was completed by analysing the association of risk factors with the occurrence of NCCLs and CDH. Loss of attachment (LOA) and gingival recession (GR) of teeth with NCCLs and/or CDH were measured using Williams periodontal probe. The diagnoses of NCCLs and CDH established following a clinical assessment yielded an overall prevalence of 61·7% and 27·1%, respectively. The 60–69 age group had the greatest proportion of subjects with NCCLs or CDH. The pre‐molars were the most commonly affected teeth type with NCCLs or CDH. The proportion of teeth with CDH associated with NCCLs increased significantly with age, but the proportion of teeth with CDH only associated with LOA or GR decreased slowly with age. The single variables and interactive effects of variables associated with the occurrence of NCCLs include the following: age group, occupation type, method of toothbrushing, frequency and method of toothbrushing, and method of toothbrushing and duration of a toothbrush used. Gender, age group, occupation type and frequency of toothbrushing were associated with the occurrence of CDH. The current study presented higher prevalence of NCCLs and CDH in a general Chinese population. Both diseases were closely associated with age and periodontal status. The portion of the population with NCCLs or CDH had different risk factors.     

釉质早期龋的光学相干断层成像与定量研究

目的 探讨光学相干断层成像技术（OCT）对釉质早期龋的成像和量化评估效能,为其在早期龋临床诊断中的应用提供实验依据。方法 采用OCT扫描牛牙光滑面早期人工龋模型和脱矿模型,获取釉质图像和光学信息,并与偏振光显微镜图像和原子吸收光谱测得的矿质损失量进行对比,采用SPSS软件包配对t检验和Pearson相关性分析进行数据分析。结果 早期龋及脱矿釉质OCT图像与偏光显微镜图像基本相符;OCT测得的早期龋组釉质的总反射率改变量低于脱矿组（P<0.05）,脱矿深度在两组间无统计学差异（P>0.05）。釉质总反射率改变量与矿质损失量呈正相关（P<0.05）。结论 OCT能够无创地、较准确地显示釉质早期龋的矿质改变,量化其病变范围和程度,在早期龋的临床诊断方面具有广阔的应用前景。     

Non‐carious cervical lesions (NCCLs) in a random sampling community population and the association of NCCLs with occlusive wear

This study investigated the prevalence, risk factors and association of occlusive wear with non‐carious cervical lesions (NCCLs) in the general Chinese population. A total of 1320 subjects were recruited, and multistage and random sampling methods of survey spots were performed. All age groups comprised similar numbers of participants and equal numbers of males and females. Each subject completed a structured interview, and all teeth of each subject were examined by a practitioner to determine NCCLs and occlusive wear. Binary logistic regression was conducted by analysing the association of risk factors with the occurrence of NCCLs. Bivariate correlation analysis was performed by determining the association of NCCLs dimension or depth with the range of occlusive wear facets. Clinical assessment showed that the overall prevalence of subjects diagnosed with NCCLs was 63%. The proportion of subjects or teeth with NCCLs significantly increased with age. Pre‐molars were the most commonly affected teeth. Single variables and interactive effects of variables associated with the occurrence of NCCLs include the following: age group, intensity of toothbrushing, frequency of fresh fruit consumption and interactive effect between intensity of toothbrushing and frequency of fresh fruit consumption. A weak positive correlation of the grading index was found between NCCLs dimension, size or depth and range of occlusive wear facets. This study reported the higher prevalence of NCCLs in the general Chinese population. Implementation of a combined strategy to reduce risk factors of NCCLs could be more effective than individual techniques; meanwhile, the occurrence of NCCL could be related to the wear degree of occlusive defects in the population studied.     

The investigation of non‐invasive techniques for treating early approximal carious lesions: an in vivo study

Objectives: The aim of this study was to examine non‐cavitated approximal caries using non‐invasive treatment methods. Materials and methods : Molar and premolar teeth with approximal caries were used in this in vivo study. Approximal caries lesions were evaluated with visual and radiographic inspection and with the DIAGNOdent device. Five groups were formed to study non‐invasive treatment, and each had at least 25 early approximal carious lesions. Patients in the control group were not treated. After the separation, either ozone application, acidulated phosphate fluoride gel, CPP‐ACP‐containing material (Tooth Mousse), or an antibacterial bonding agent (Clearfil Protect Bond) was used. For 18 months after the non‐invasive treatment, radiological controls were used to observe the progress of the initial and approximal caries in the 1st, 3rd, 6th and 12th months of follow‐up. A Mann–Whitney U‐test was used to perform the statistical analysis; in‐group comparisons were made with the Wilcoxon signed‐rank test, and a quantitative assessment was performed using a chi‐squared test. Results: At the end of 18 months, the caries lesions in the control group were observed to progress (P < 0.01). The lesions that were scored as 1a during a visual inspection recovered by using non‐invasive treatments. Conclusion: Approximal caries lesions that were detected at the early stages remained stationary when using antibacterial agents and materials that promoted remineralisation. Clinical relevance: Antibacterial agents and remineralisation materials can be used in treatment of early approximal caries lesions.     

The correlation of DIFOTI to clinical and radiographic images in Class II carious lesions

BACKGROUND: The authors conducted a study to evaluate the correlation between digital imaging fiber-optic transillumination (DIFOTI) (KaVo Dental, Lake Zurich, Ill.) and clinical and radiographic images in estimating the true clinical axial extension of Class II carious lesions. METHODS: The authors examined 51 Class II carious lesions visually, imaged them by means of DIFOTI and radiographed them with D-speed film and a complementary metal oxide silicon (CMOS)-based digital radiographic sensor. They validated axial extension of the lesions clinically. They compared the clinical and radiographic depths of the carious lesion with the size of the lesion on the DIFOTI images. RESULTS: The authors detected 84 percent of the lesions with DIFOTI, and 82 percent showed a visible dark shadow under the marginal ridge when examined clinically. DIFOTI correlated significantly with the clinical depth of decay (Pearson r = 0.43189). The combination of a CMOS digital sensor and DIFOTI (R2 = 0.7210) provided readings closer to the clinical measures than did the combination of D-speed film and DIFOTI (R2 = 0.6215). CONCLUSIONS: DIFOTI images correlated with clinical depth, especially in smaller lesions, and improved the estimation of lesion size when used in conjunction with the CMOS digital sensor and D-speed images. CLINICAL IMPLICATIONS: Using radiographs in combination with DIFOTI images could help clinicians determine the presence and, to some extent, the size of proximal caries, especially in smaller lesions.     

OCT检出面窝沟早期人工龋的形态学比较研究

目的：探讨光学相干断层成像技术（OCT）检测窝沟早期人工龋的可行性。方法：利用pH循环法建立面窝沟早期龋模型,对其进行OCT扫描,获取二维伪彩图。在扫描路径所在位置制作牙磨片,进行偏光显微镜检测,获取其组织学图像。将二者所获取的图像进行形态学比较分析。结果：面窝沟健康牙釉质表面呈现一条光背向散射增强带,脱矿后牙釉质表面光反射和背向散射信号增强,光背向散射增强带厚度增加,光背向散射增强带下光信号迅速衰减。OCT检测出的龋损形态及深度与偏光显微镜下的组织学检测结果相符。结论：OCT可灵敏准确地检出人牙窝沟早期龋。