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991.

Introduction

The aim of this systematic review was to assign levels of evidence (LOEs) to existing clinical articles related to the outcome of regenerative endodontic therapy and to evaluate the clinical and radiographic outcomes of this treatment modality.

Methods

Electronic search was executed in PubMed, Scopus, and Cochrane databases by using appropriate Medical Subject Headings terms covering the period from January 1993 to December 2013. Additional publications from hand-searching and reference section of each relevant article enriched the article list. The LOE of each article was assessed according to guidelines provided by the Oxford Centre of Evidence-Based Medicine. Quality assessment of the observational studies was executed by using the Newcastle-Ottawa scale.

Results

Fifty-one relevant publications were included in this review. There were 2 high-level cohort studies (LOE 2), 8 case series (LOE 4), and 41 case reports (LOE 5). The vast majority of the treated teeth in those publications showed resolution of clinical signs, symptoms, and periapical radiolucencies at follow-up period. Furthermore, the majority of treated teeth presented further increase in root length and root wall thickness and apical closure at the follow-up period. However, because of lack of sufficient high-level evidence it was not possible to answer totally the review question and determine definitely the outcome of regenerative endodontic therapy.

Conclusions

The lack of adequate high-level studies that could possibly strengthen the satisfactory current data and allow practicing more evidence-based dentistry constitutes a significant knowledge gap in the endodontic literature. However, the current best available evidence undeniably allows clinicians to provide this treatment modality safely to patients.  相似文献   
992.

Objective

To test the following hypotheses: (1) degree of conversion (DC) and polymerization stress (PS) increase with composite temperature (2) reduced light-exposure applied to pre-heated composites produces similar conversion as room temperature with decreased PS.

Methods

Composite specimens (diameter: 5 mm, height: 2 mm) were tested isothermally at 22 °C (control), 40 °C, and 60 °C using light-exposures of 5 or 20 s (control). DC was accessed 5 min after light initiation by FTIR at the specimen bottom surface. Maximum and final PS were determined, also isothermally, for 5 min on a universal testing machine. Non-isothermal stress was also measured with composite maintained at 22 °C or 60 °C, and irradiated for 20 s at 30 °C. Data were analyzed using two-way ANOVA/Tukey and Student's t-test (α = 5%).

Results

Both DC and isothermal maximum stress increased with temperature (p < 0.001) and exposure duration (p < 0.001). Isothermal maximum/final stress (MPa) were 3.4 ± 2.0b/3.4 ± 2.0A (22 °C), 3.7 ± 1.5b/3.6 ± 1.4A (40 °C) and 5.1 ± 2.0a/4.0 ± 1.6A (60 °C). Conversion values (%) were 39.2 ± 7.1c (22 °C), 50.0 ± 5.4b (40 °C) and 58.5 ± 5.7a (60 °C). The reduction of light exposure duration (from 20 s to 5 s) with pre-heated composite yielded the same or significantly higher conversion (%) than control (22 °C, 20 s/control: 45.4 ± 1.8b, 40 °C, 5 s s: 45.1 ± 0.5b, 60 °C, 5 s s: 53.7 ± 2.7a, p < 0.01). Non-Isothermal conditions showed significantly higher stress for 60 °C than 22 °C (in MPa, maximum: 4.7 ± 0.5 and 3.7 ± 0.4, final: 4.6 ± 0.6 and 3.6 ± 0.4, respectively).Clinical significance: Increasing composite temperature allows for reduced exposure duration and lower polymerization stress (both maximum and final) while maintaining or increasing degree of conversion.  相似文献   
993.
《Dental materials》2014,30(12):1316-1324
ObjectivesPhotopolymerized composites are used in a broad range of applications with their performance largely directed by reaction kinetics and contraction accompanying polymerization. The present study was to demonstrate an instrument capable of simultaneously collecting multiple kinetics parameters for a wide range of photopolymerizable systems: degree of conversion (DC), reaction exotherm, and polymerization stress (PS).MethodsOur system consisted of a cantilever beam-based instrument (tensometer) that has been optimized to capture a large range of stress generated by lightly-filled to highly-filled composites. The sample configuration allows the tensometer to be coupled to a fast near infrared (NIR) spectrometer collecting spectra in transmission mode.ResultsUsing our instrument design, simultaneous measurements of PS and DC are performed, for the first time, on a commercial composite with ≈80% (by mass) silica particle fillers. The in situ NIR spectrometer collects more than 10 spectra per second, allowing for thorough characterization of reaction kinetics. With increased instrument sensitivity coupled with the ability to collect real time reaction kinetics information, we show that the external constraint imposed by the cantilever beam during polymerization could affect the rate of cure and final degree of polymerization.SignificanceThe present simultaneous measurement technique is expected to provide new insights into kinetics and property relationships for photopolymerized composites with high filler content such as dental restorative composites.  相似文献   
994.
目的:应用一种新的全颌曲面断层分析方法来判断牙周炎组和正常组之间的相对骨密度(RBD)的差异,并预测下颌角骨折的风险.方法:回顾性研究60例牙周炎患者和60例正常组病例,应用全颌曲面断层片比较其相对骨密度(RBD).同时,调查所有患者的下颌角骨折病史并做记录.结果:牙周炎组和正常组之间的三个RDB指数的差异有明显统计学意义.正常组有3例下颌角骨折患者,牙周炎组有8例下颌角骨折病例.两组下颌角骨折患者RBD指数均相对较低.结论:牙周炎组和正常组的RBD指数之间具有明显统计学意义,RBD指数可以作为普通全颌曲面断层片的一种新的分析方法.可用做牙周炎的筛选工作,并在一定程度上可以预测发生下颌角骨折的风险.  相似文献   
995.
The surgical resection of a large unfavourable Shamblin type III carotid body tumour (CBT) can be very challenging technically, with many potential significant complications. Preoperative embolization aids in shrinking the lesion, reducing intraoperative blood loss, and improving visualization of the surgical field. Preoperative internal carotid artery (ICA) stenting aids in reinforcing the arterial wall, thereby providing a better dissection plane. A woman presented to our institution with a large right-sided CBT. Failure of the preoperative temporary balloon occlusion (TBO) test emphasized the importance of intraoperative preservation of the ipsilateral ICA. A combination of both preoperative embolization and carotid stenting allowed a less hazardous radical resection of the CBT. An almost bloodless surgical field permitted meticulous dissection, hence reducing the risk of intraoperative vascular and nerve injury. Embolization and carotid stenting prior to surgical resection should be considered in cases with bilateral CBT or a skull base orientated high CBT, and for those with intracranial extension and patients who have failed the TBO test.  相似文献   
996.

Purpose

The present study was carried out to evaluate the usefulness of mini retromandibular approach on accessibility, scarring and stability in open reduction and internal fixation of sub condylar fractures.

Materials and Methods

Fifteen patients underwent open reduction and rigid fixation of middle and low subcondylar fractures, with mini-retro mandibular approach.

Results

No signs of infection were observed in any patient postoperatively. Surgical scar was imperceptible and esthetically acceptable in all the cases. Out of 15 patients, only one patient had discrepancy in occlusion and after 2 months satisfactory centric occlusion was achieved. Salivary fistula (parotid fistula) was observed in 3 cases within 1 week postoperatively, which was treated spontaneously with the use of hypertonic saline. Transient facial nerve weakness was observed in 2 patients, in one patient it resolved in 4 weeks postoperatively and in second patient 3 months postoperatively. Mouth opening increased in all the patients with time. Average mouth opening at 1 week interval was 19.6 mm, at 2 months interval 28.2 mm, and after 6 months 38.33 mm suggesting that mouth opening gradually increased with time. At the end of 2 months postoperatively none of the patients had any restriction in lateral movements. At 2 months postoperatively 4 patients had deviation but none of the patients had any deviation 6 months postoperatively.

Conclusion

It is evident from the results of our study that open reduction and internal fixation using mini-retromandibular approach is good treatment option in management of mandibular condylar fractures.  相似文献   
997.

Objectives

The aim of this paper is to summarize different diagnostic criteria as well as probable aetiopathogenesis of bisphosphonates related osteonecrosis of the jaw.

Materials and Methods

The electronic search of peer-reviewed journals were performed in MEDLINE (PubMed) database in order to find the relevant articles on bisphosphonates related osteonecrosis of the jaw (BP-related ONJ). The search was restricted to English language articles, published from January 2002 to May 2013. On the basis of these articles, probable aetiopathogenesis and different diagnostic criteria of BP-related ONJ were summarized.

Results

BP-related ONJ is related to the development of avascular necrosis or dead jaw bones. In recent literature many given hypotheses show the aetiopathogenesis and diagnosis of BP-related ONJ which are interlinked and have multifactorial nature. Their diagnosis revolves around four main diagnostic criteria that differentiate it from other conditions which can delay bone healing.

Conclusions

Factors like potency of bisphosphonates, biology of jaw bone, antiangiogenic property of bisphosphonates and soft tissue toxicity in combination with present infection, other drugs, pre-existing pathologies, compromised immune response and dentoalveolar trauma may lead to development of BP-related ONJ.  相似文献   
998.
Lipomas are among the most common benign tumors affecting the human body. However, they are relatively uncommon in the oral cavity. Oral lipomas are likely to affect cheek, tongue, lips, gingiva and rarely the floor of the mouth. We report a case of huge lipoma of the floor of the mouth, associated with difficulty in speech and mastication in a 72-year-old male. The tumor was completely excised and sent for histopathological examination, which confirmed the tumor to be a simple classical lipoma.  相似文献   
999.
The study was undertaken to evaluate the reliability of different facial measurements for determination of vertical dimension of occlusion in edentulous subjects using accepted facial dimensions recorded from dentulous subjects. The hypothesis was that facial measurements can be used to obtain the vertical dimension of occlusion for edentulous patients where no pre-extraction records exist. A total of 180 subjects were selected in the age groups of 50–60 years, consisting of 75 dentate male and 75 dentate female subjects for whom different facial measurements were recorded including vertical dimension of occlusion and rest, and 15 edentulous male and 15 edentulous female subjects for whom all the facial measurements were recorded including the vertical dimension of rest and occlusion following construction of upper and lower complete dentures. The left outer canthus of eye to angle of mouth distance and the right Ear–Eye distance were found to be as valuable adjuncts in the determination of occlusal vertical dimension. The Glabella–Subnasion distance, the Pupil–Stomion distance, the Pupil–Rima Oris distance and the distance between the two Angles of the Mouth did not have a significant role in the determination of the occlusal vertical dimension. The vertical dimension can be determined with reasonable accuracy by utilizing other facial measurements for patients for whom no pre-extraction records exist.  相似文献   
1000.
<正>口底缺损修复的目的主要是保持舌的活动度,以恢复其语言和吞咽功能。由于口底解剖结构的特殊性,口底缺损很难通过直接拉拢缝合来关闭伤口。植皮修复也会由于后期的瘢痕挛缩而影响舌的功能运动,舌瓣修复会大大影响舌的活动度,胸大肌皮瓣或背阔肌皮瓣的体积过大,现在已很少被采用。因此,要根据口底缺损大小和病人全身情况来选择合适的游离、带蒂或局部组织瓣移植修复。本文就近年来这方面的研究进展作一综述。  相似文献   
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