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81.

Introduction

This study examined the identity of the microbiome of deep dentinal caries and its correlation with the inflammation status of caries-induced pulpitis.

Methods

Seventy-five cases were diagnosed based on the American Association of Endodontics's diagnostic criteria and divided into 4 groups: normal pulp with deep caries (NP; n = 13), reversible pulpitis with only cold-evoked pain (CRP; n = 17), reversible pulpitis with both cold/heat-evoked pain (CHRP; n = 24), and symptomatic irreversible pulpitis (SIP; n = 21). Samples were sequenced by 16S rDNA. Alpha and beta diversity were determined. Linear discriminant analysis effect size (LEfSe) analysis was used to detect intergroup differences, and receiver operating characteristic (ROC) curves were generated to assess the role of the caries microbiome in caries-induced pulpitis.

Results

The 16S rDNA sequencing yielded 9100 operational taxonomic units. Lactobacillus had the highest relative abundance at the genus level among the 4 groups. There were significant differences in the distribution of the microbiome among the groups. In an alpha diversity analysis, species richness differed between the CRP group and the other groups. In a beta diversity analysis, the distribution of microorganisms in the SIP group was significantly different from those in the other 3 groups. LEfSe analysis indicated substantial differences in the microbiome among the groups, and the areas under the ROC curves (AUC) were all high (AUC: 0.734–0.952).

Conclusions

Characterization of the caries microbiome has the potential to become an auxiliary method for the diagnosis of pulpitis. This finding may prompt new research on diagnostic strategies for caries-induced pulpitis.  相似文献   
82.
83.
The purpose of this article is to review the literature on interprofessional education (IPE) and report on a preliminary survey of the current status of interprofessional education in seven academic health centers (AHCs) that have schools of dentistry associated with them. There is wide variability in interpretation of the term "interprofessional," and many barriers to interprofessional education exist including already overcrowded curricula in health professions schools, lack of support from faculty and administration, and financial constraints. Based on interviews completed at the authors' home institutions, it was recommended that topics such as ethics, communication skills, evidence-based practice, and informatics could be effectively taught in an interprofessional manner. Currently, some academic health centers are attempting to develop interprofessional education programs, but most of these efforts do not include dental students. Of the seven AHCs investigated in this study, only two had formal interprofessional educational activities that involved students from two or more health professions education programs. Dental school participants in this study professed a strong interest in interprofessional programs, but many interviewees from other professional schools and AHC administrators perceived that the dental school was isolated from other schools and disinterested in IPE. Many health care setting models in the future will include dentists as part of an interdisciplinary health care team; consequently, it is important for dental schools to become an active participant in future interprofessional educational initiatives.  相似文献   
84.
This article presents a comparison of screw-retained and cement-retained implant prostheses based on the literature. The advantages, disadvantages, and limitations of the 2 different types of restorations are discussed, because it is important to understand the influence of the attachment mechanism on many clinical aspects of implant dentistry. Several factors essential to the long-term success of any implant prosthesis were reviewed with regard to both methods of fixation. These factors include: (1) ease of fabrication and cost, (2) passivity of the framework, (3) retention, (4) occlusion, (5) esthetics, (6) delivery, and (7) retrievability. (More than 50 references).  相似文献   
85.
The use of transpositioned flap (lipswitch) vestibuloplasty combined with implant surgery in patients with severely resorbed atrophic edentulous ridges is reviewed. The cases of 17 patients with severely resorbed atrophic edentulous ridges at the mandible undergoing implant rehabilitation were reviewed. Lipswitch vestibuloplasty was followed immediately by the implant surgery. Postoperative follow-up consisted of clinical and radiographic examinations. Seventeen patients with atrophic ridges (12 class II and 5 class III) each had 2 implant fixtures placed in the mandible as abutments for a clip and bar overdenture. The average time of follow-up was 6 years. Before surgery, all patients had severely atrophic ridges with a compromised shallow vestibule of varying degrees. Satisfactory results were observed in regard to the immediate and long-term morphology of the vestibule, the health of the peri-implant tissue, the stability of implant fixtures, and the functionality of the prostheses. The lipswitch vestibuloplasty offers a safe and convenient method of surgical access for implant fixture installation, with the advantage of rebuilding the vestibule of a compromised atrophic ridge in the anterior mandible.  相似文献   
86.
This article describes the use of SLS to produce a wax prototype for the fabrication of a partial nasal prosthesis. This technique may be an alternative to more conventional laboratory techniques for facial prosthesis fabrication and allows direct generation of definitive wax patterns. With the satisfying effect of nasal defect restoration, patients may be effectively rehabilitated and derive emotional and physical benefit from the treatment provided.  相似文献   
87.
微型种植钉的长度直径对生物力学的影响   总被引:5,自引:0,他引:5  
目的对比评价临床常用的3种类型(不同长度、直径)微型种植钉的生物力学特点。方法应用种植钉48枚,新西兰大白兔8只。采用拉出试验,扭转强度试验,在即刻与愈合4周后进行生物力学测量。结果长度为6mm,直径为1.9mm的种植钉相对于同等长度,直径为1.5mm的种植钉在“种植后即刻”与“愈合4周”时,最大剪切力均表现出显著性优势。愈合4周后,直径为1.9mm的种植体在最大扭转强度上表现出显著性的优势。结论在骨质量较差的部位选择较大直径的种植体有利于种植体的稳定。  相似文献   
88.
头颈部恶性肿瘤患者血清可溶性白介素2受体水平   总被引:1,自引:0,他引:1  
目的:研究头颈部恶性肿瘤患者血清可溶性白介素2受体(sIL-2R)水平的变化。方法:用双抗体夹心法对60例头颈部恶性肿瘤患者,60例良性肿瘤患者以及50例健康对照者的血清sIL-2R水平进行检测。结果:头颈部恶性肿瘤患者组血清sIL-2R水平显著高于健康对照组(P<0.01),而良性肿瘤患者组血清sIL-2R水平与健康对照组无统计学差异(P>0.05)。结论:血清中高sIL-2R水平可能与头颈部恶性肿瘤的发生有相关性。  相似文献   
89.
Resonance frequency (RF) analysis technology was used to design a new dental implant stability detector. To calibrate and test the performance of this novel apparatus, in vitro and in vivo models, respectively, were used. The RF values of the test implants detected using our new device and a commercially available analogous device (Osstell) were compared. Further, implant stability status was also detected clinically using our device at 2, 4, 8, and 12 weeks after surgery. A high correlation was demonstrated between the values measured with the two devices (y = 0.31x-12.45; R2 = 0.98, p < 0.05). In our clinical tests, an initial RF value above 10.0 kHz indicated that the implant was ready to accept functional loading, while values in the 4.0-10.0 kHz range reflected the need for further osseointegration. In conclusion, these results indicated that our new device might be useful in a clinical setting for evaluating the healing status of a placed implant.  相似文献   
90.
目的:探讨倾斜种植体作为一种避免上颌窦植骨的方法,应用于上颌骨后牙区骨量不足患者种植修复的可靠性。方法:2005年1月—2007年12月间,21例患者共27个固定桥修复上颌后牙缺失,分别使用ITI和Br覽nemark 2种种植系统共植入78颗种植体,其中34颗种植体采用倾斜植入,44颗轴向植入。所有患者均为上颌后牙区骨量不足无法直接接受常规种植体植入。种植体植入后常规愈合3个月,除1颗种植体失败外,其余种植体均功能性负载支持固定义齿修复,修复方式为黏结固位和螺丝固位。每例患者均于负载后12、24和36个月接受临床和放射学随访检查。采用SPSS11.0软件包对数据进行统计学处理。结果:上颌有1颗轴向种植体在术后2个月时失败,倾斜种植体无失败。随访时间为36个月。上颌轴向种植体的累积存活率为97.72%,倾斜种植体的累积存活率为100%,修复成功率为100%。随访期间,种植体周围软组织保持稳定,平均探诊深度和附着水平无明显变化。结论:倾斜种植体作为一种上颌骨后牙区骨量不足患者的治疗方法是可靠的,能有效避免植骨手术,并节约治疗时间。  相似文献   
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