The influence of zero-value subtraction on the performance of two laser fluorescence devices for detecting occlusal caries in vitro

BACKGROUND: The aim of this study was to evaluate the influence of zero-value subtraction on the performance of two laser fluorescence (LF) devices developed to detect occlusal caries. METHODS: The authors selected 119 permanent molars. Two examiners assessed three areas (cuspal, middle and cervical) of both mesial and distal portions of the buccal surface and one occlusal site using an LF device and an LF pen. For each tooth, the authors subtracted the value measured in the cuspal, middle and cervical areas in the buccal surface from the value measured in the respective occlusal site. RESULTS: The authors observed differences among the readings for both devices in the cuspal, middle and cervical areas in the buccal surface as well as differences for both devices with and without the zero-value subtraction in the occlusal surface. When the authors did not perform the zero-value subtraction, they found statistically significant differences for sensitivity and accuracy for the LF device. When this was done with the LF pen, specificity increased and sensitivity decreased significantly. CONCLUSIONS: For the LF device, the zero-value subtraction decreased the sensitivity. For this reason, the authors concluded that clinicians can obtain measures with the LF device effectively without using zero-value subtraction. For the LF pen, however, the absence of the zero-value subtraction changed both the sensitivity and specificity, and so the authors concluded that clinicians should not eliminate this step from the procedure. CLINICAL IMPLICATIONS: When using the LF device, clinicians might not need to perform the zero-value subtraction; however, for the LF pen, clinicians should do so.     

上颌后牙区骨膨胀技术结合上颌窦闭式提升术植入CDIC种植体的探讨

目的：探讨一种创伤较小的后牙牙槽脊增宽，同期植入CDIC种植体的方法。方法：通过使用后牙骨挤压骨膨胀的技术获得初期固位。结果：两例病例获得成功，近期成功率达100％。结论：上颌后牙区骨挤压骨膨胀技术结合上颌窦闭式提升术植入CDIC种植体是一种解决后牙区骨萎缩的方法。     

Dental panoramic radiographic evaluation in bisphosphonate-associated osteonecrosis of the jaws

Objectives:  To determine the extent to which clinical and radiographic features of bisphosphonate-associated osteonecrosis of the jaw (BONJ) are correlated.
Design:  Retrospective case review.
Methods:  The records of 39 patients diagnosed with BONJ and examined by panoramic radiography were retrospectively evaluated. The arches were divided into sextants ( n  = 234) and evaluated for the following signs: sclerosis, surface irregularity, sockets, fragmentation and lysis.
Main outcome measures:  The McNemar, Kruskall–Wallis and equivalency tests were performed to analyze the association between clinical and radiographic signs and BONJ severity.
Results:  Sixty-two out of 234 sextants were abnormal by clinical criteria and 61 out of 234 sextants demonstrated at least one radiographic abnormality. There was agreement between clinical and radiographic detection in 41 sextants. The data showed equivalency between BONJ diagnosis and both sclerosis and surface irregularity. The correlation between number of clinical sites and any radiographic finding was significant in the maxilla ( P  < 0.001) but not in the mandible ( P  = 0.178). The total number of radiographic signs per patient increased with BONJ stage.
Conclusion:  Focal panoramic radiographic findings of sclerosis and surface irregularity correlate with clinical sites of BONJ. This may be a useful and reliable tool to detect early changes of BONJ or to confirm a clinical diagnosis.     

梯度旋转下降法修复单侧完全性唇裂的初步研究

目的探讨梯度旋转下降法修复单侧完全性唇裂的术后效果。方法分析85例单侧完全性唇腭裂患儿的术前，术后即刻以及术后一年的面部石膏模型唇部指标，同时比较这85例单侧完全性唇腭裂患儿术后一年的唇部指标与相似年龄的45例单纯不完全性腭裂患儿的唇部指标。结果在术后即刻虽然健患侧唇高、健患侧唇宽的差值减小，但其健患侧仍不协调。术后一年，健患侧唇高和健患侧唇宽都达到协调。与对照组进行比较，唇高在术后一年恢复到正常值，而唇宽在一年后无论是健侧还是患侧，仍然低于正常值。结论采用梯度旋转下降法修复单侧完全性唇裂可以达到一个很好的唇部美观效果。     

Differential expression of salivary S100A7 in oral submucous fibrosis

Aim

To investigate the expression of salivary S100A7 levels among patients with oral submucous fibrosis (OSF) and healthy controls.

表面水分和不同种类的手套对于硅橡胶印模材聚合时间的影响

目的:本文研究了表面水分和不同种类的手套对于硅橡胶印膜材料聚合时间的影响.方法:使用3种手套:一次性聚乙烯塑料薄膜手套,灭菌橡胶医用手套(无粉),以及橡胶检查手套(预撒粉),分别在潮湿和干燥环境下手动混合DENT SILICONE-PLUS重体型硅橡咬印模材,并记录其硬化时间.结果:干燥情况下使用塑料薄膜手套时,橡胶印模材聚合时间最短,平均2分10秒;乳胶材料和表面水分均可延长聚合时间,达到3～分钟时间;而预撒粉则可显著延长聚合时间,超过1小时.结论:临床运用硅橡胶制取印模时,建议使用一次性聚乙烯塑料薄膜手套在干燥环境下进行操作,预撒粉的橡胶检查手套必须更换,以避免操作失败.     

The supernumerary cheek tooth in tabby/EDA mice-a reminiscence of the premolar in mouse ancestors

OBJECTIVE: A supernumerary cheek tooth occurs mesially to the first molar in tabby/EDA (Ta) mice affected by hypohidrotic ectodermal dysplasia. The supernumerary tooth (S) has been hypothetically homologized to the premolar, which has disappeared during mouse evolution. DESIGN: This hypothesis was tested using available morphological data on the lower cheek teeth in wild type (WT) and Ta mice. RESULTS: The presence of S is accompanied by a reduction in the mesial portion of the M(1) in mutant mice. 3D reconstructions suggest that the S in Ta homo/hemizygous embryos originates from a split off the mesial portion of the first molar (M(1)) cap. In WT embryos, two vestigial tooth primordia are transiently distinct in front of the M(1). The distal vestige has the form of a wide bud and participates during the development of the mesial portion of the M(1). This bud has been homologized with the vestigial primordium of the fourth premolar of mouse ancestors. The premolar disappearance coincided with a mesial lengthening of the M(1) during mouse evolution. The incorporation of the distal premolar vestige into the mesial part of the M(1) in WT embryos can be regarded as a repetition of the premolar disappearance during evolution. CONCLUSION:: Ontogenetic and phylogenetic data support that the S in Ta mice arises due to the segregation of the distal premolar vestige from the molar dentition and thus represents an evolutionary throwback (atavism).     

Five-year evaluation of implants placed at extraction and with dehiscences and fenestration defects augmented with ePTFE membranes: results from a prospective multicenter study

Background: Barrier membranes have been used to promote bone ingrowth on implants with dehiscences and fenestrations. Membranes also have been used to protect defects adjacent to implants placed at the time of extraction. The concept of guided bone regeneration relates to preferentially allowing cells from bone to migrate into various defects while excluding fibrous tissue and epithelium. The purpose of these procedures is to enhance bone-to-implant contact at the treated sites and to prevent mucosal complications. Purpose: The purpose of this article is to report clinical outcomes for implants placed at the time of extraction and augmented with expanded polytetrafluoroethylene (ePTFE) and followed for 5 years. The outcomes for implants with dehiscences and fenestrations augmented with ePTFE barriers and followed up to 5 years also are reported. Methods and Materials: Four treatment centers participated in this study (Tucson, Gothenburg, Spokane, and Leuven). In the extraction group, teeth were removed for varying reasons, and Brånemark implants were placed and stabilized within the host bone. Defects present at the coronal implant aspect were covered with ePTFE barrier membranes. Flaps were rotated to cover the membrane-treated sites. If exposure of the material occurred prior to second-stage surgery, the membranes were removed. Barriers remaining unexposed were removed at second-stage surgery. The implants were followed up to 5 years. In the fenestration and dehiscence group, implants with exposed threads were augmented with ePTFE barrier membranes. The barriers were removed at appropriate intervals, and the patients were followed up to 5 years. Radiographic measurements were made from nonstandardized periapical radiographs at abutment connection and 1, 3, and 5-year follow-up visits. Results: Forty patients participated in the extraction group. They received a total of 49 implants. Three implants failed prior to loading. The 5-year cumulative survival rates for implants placed at the time of extraction were 93.9% and 93.8%, respectively, for maxillary and mandibular implants. The average maxillary mesial and distal marginal bone loss (1–5 yr) was 0.3 mm (standard deviation [SD] = 1.5) and 0.3 mm (SD = 1.0). In mandibles, the average mesial and distal bone loss (1–5 yr) was -0.2 mm (SD = 0.5) and -0.05 mm (SD = 0.6), respectively. The dehiscence and fenestration group included 44 patients. Twenty-six were followed for up to 5 years. Eight patients experienced total implant failure. For dehiscences and fenestrations, the cumulative survival rates were 76.8% and 83.8% for maxillary and mandibular implants, respectively. The average maxillary mesial and distal bone loss (1–5 yr) was 0.4 mm (SD = 0.8) and 0.2 mm (SD = 0.9), respectively. In mandibles, the average mesial and distal marginal bone loss was 0.3 mm (SD = 0.9) and 0.3 mm (SD = 0.8), respectively. Conclusions: Implants placed at the time of extraction and augmented with ePTFE barrier membranes have favorable long-term predictability. On the other hand, long-term evaluation of implant dehiscences and fenestrations augmented with barrier membranes indicates that they have less favorable 5-year survival rates. Membrane augmentation of these may be questioned.     

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目的验证不同方法诊断下颌第二磨牙C形根管系统发生率的准确性。方法收集济南市口腔医院和山东大学附属省立医院自2007年3月至2007年11月间因各种原因拔除的下颌第二磨牙共90颗,分离出具有C形根管特征的共32颗,拍摄术前X线片后开髓和清理髓室,手术显微镜下观察并记录根管口的形态,将初尖锉插入根管内拍初尖锉片。分析术前X线片和手术显微镜对C形根管系统诊断的成功率。对C形根管系统的初尖锉片进行分析,评价初尖锉片对于判断C形根管系统解剖形态的意义。结果32颗具有C形根管特征的离体牙中,通过术前X线片可以诊断的为20颗;通过手术显微镜下根管口的形态可以诊断的为28颗。C形根管的初尖锉片上,19颗表现为Ⅰ型,9颗表现为Ⅱ型,4颗表现为Ⅲ型。结论C形根管系统的诊断应采取术前X线片与根管显微镜相结合的方法,初尖锉片对于判断C形根管系统的分型具有较大的意义。