p53基因抑制涎腺腺样囊性癌细胞端粒酶及增殖活性

目的研究外源性野生型p53基因对涎腺腺样囊性癌细胞的抑制作用。方法构建携带野生型p53基因的腺病毒表达载体，以脂质体法转染涎腺腺样囊性癌SACC-83细胞，RT-PCR检测p53基因表达；采用TRAP—PCR—ELISA法检测转染细胞端粒酶活性，荧光素酶分析法检测人端粒酶逆转录酶基因（hTERT）肩动子的转录；流式细胞术、软琼脂集落实验及裸鼠成瘤实验观察细胞生物特性的变化。结果外源性野生型p53基因导入使p53基因在涎腺腺样囊性癌细胞SACC-83中表达增强，其端粒酶活性降低、hTERT启动子转录抑制；转染细胞出现G1期阻滞，软琼脂集落形成率减少，裸鼠成瘤能力降低。结论腺病毒载体介导的外源性野生型p53基因可以抑制涎腺腺样囊性癌细胞端粒酶活性及细胞恶性表型。     

Analysis of postoperative symptoms following surgical endodontic treatment.

OBJECTIVE: The purpose of this prospective study was to analyze postoperative pain and swelling of patients undergoing surgical endodontic treatment using a strict protocol incorporating measures to control postoperative symptoms. METHOD AND MATERIALS: The study consisted of 82 patients referred for surgical endodontic treatment. All surgical procedures were performed using a microsurgical technique employing strict protocol. All patients were premedicated with a single dose of oral dexamethasone (8 mg) preoperatively and two single doses (4 mg) 1 and 2 days postoperatively. Antibiotics were prescribed selectively only when severe symptoms were present due to infection. Patients were administered chlorhexidine mouthwash twice daily starting 3 days before the operation and an additional 7 days postoperatively starting the day after surgery. Cold compresses were applied on the skin at the site of surgery intermittently every 15 minutes during the operative day. Pain and swelling were recorded pre- and postoperatively, and the influence of different variables on postoperative sequelae were analyzed. RESULTS: One day postoperatively, 76.4% of the patients were completely pain free, less than 4% had moderate pain, and 64.7% did not report any swelling. The preoperative symptoms significantly influenced the pain experience post-surgery. CONCLUSION: There was a low incidence of postoperative pain and swelling following endodontic surgical treatment according to protocol with measures to control postoperative signs and symptoms. Patients with preoperative pain were more likely to have postoperative pain.     

Advocacy training in US advanced pediatric dentistry training programs

PURPOSE: This study: (1) assessed pediatric dentistry residency program directors' attitudes toward and involvement in advocacy training; and (2) identified types and extent of advocacy training in U.S. pediatric dentistry programs. METHODS: Between October 2005 and February 2006, all 66 pediatric dentistry residency program directors were invited to complete a 62-item online questionnaire. The survey investigated: (1) directors' attitudes toward advocacy training; (2) nature of advocacy training offered during residency; (3) extent of resident involvement in different settings; and (4) directors' involvement in advocacy. RESULTS: Forty-two program directors responded (64%). Overall, respondents agreed that advocacy by pediatric dentists for children beyond the dental office was important and that residency programs should provide advocacy training. Most programs did not routinely offer advocacy opportunities in nonclinical settings. Over half of programs required community outreach clinic rotations for all residents. One third offered didactic curriculum in the legislative process. Over 50% of program directors reported personal involvement in legislative oral health lobbying within 3 years, but fewer than a third were involved with professional political action committees (PACs). CONCLUSIONS: Advocacy is seen as on important in pediatric dentistry but variation in attitudes of program directors and program offerings exists in US training programs.     

Management of interdental papillae loss with forced eruption, immediate implantation, and root-form pontic

BACKGROUND: A 25-year-old Asian woman complained of an unesthetic black triangle between her upper right front teeth. Defective interdental papillae may result from external root resorption, which makes esthetic restoration more difficult. A combined use of forced eruption, immediate implant placement, and a root-form pontic made a successful esthetic and functional restoration. METHODS: The treatment sequences of this patient included short-term forced eruption, subsequent immediate implant placement after tooth extraction, and a provisional root-form pontic restoration. A final prosthesis was completed 6 months later, followed by clinical maintenance. RESULTS: Papillae were augmented by forced eruption. After immediate implantation and root-form pontic placement had been performed, the peri-implant soft and hard tissues were manipulated and maintained in a stable state. CONCLUSIONS: We successfully reconstructed the interdental papillae and replaced the deficient tooth with an immediate implantation. During 2 years of follow-up, the implant and peri-implant structures remained stable and healthy.     

A newly designed resonance frequency analysis device for dental implant stability detection

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.     

Oral health care system in Chinese Mainland

The purpose of this review is to describe the training of dental professionals and to give an overview of the oral health care system in Mainland China. It may be of interest and importance for American readers to become aware that there are alternative practice structures and the world is getting smaller.     

Transient loss of power of accommodation in 1 eye following inferior alveolar nerve block: report of 2 cases

Unintended intravascular injection from inferior alveolar nerve blocks can result in frustrating distant complications affecting such structures as the middle ear and eyes. Possible complications affecting the eyes include blurring of vision, diplopia, mydriasis, palpebral ptosis and amaurosis (temporary or permanent). In this article, we present a complication that has been reported only rarely. Two patients developed transient loss of power of accommodation of the eye resulting in blurred vision after routine inferior alveolar nerve blocks on the ipsilateral side. Clear vision returned within 10-15 minutes after completion of the blocks. The possible explanation for this phenomenon is accidental injection into the neurovascular bundle of local anesthetic agents, which were carried via the blood to the orbital region. This resulted in paralysis of a branch of cranial nerve III, the short ciliary nerves that innervate the ciliary muscle, which controls accommodation.     

Immunohistochemical demonstration of epithelial glutathione S-transferase isoenzymes in normal, benign, premalignant and malignant human oral mucosa

The expression and localization of glutathione S-transferase (GST) isoenzymes in the epithelium of normal oral mucosa ( n = 9), overlying reactive fibrous hyperplasia ( n =9), and of potentially malignant [leukoplakia ( n =25), submucous fibrosis ( n =12), verrucous hyperplasia ( n =16)] and malignant [squamous cell carcinoma ( n =36), verrucous carcinoma ( n =13)] oral lesions were examined immunohistochemically using polyclonal antibodies raised against GST isoenzymes (alpha, mu and pi) with the standard avidin-biotin-peroxidase complex (ABC) method. GST alpha, mu and pi were almost completely absent in the epithelium of normal oral mucosa and overlying benign fibrous tissues. GST alpha staining was cytoplasmic and focally positive, while GST mu staining was similar to but weaker than that seen for GST alpha. GST pi showed both cytoplasmic and nuclear staining and was expressed in 60% of leukoplakias with mild dysplasia ( n =15), 80% of leukoplakias with moderate to severe dysplasia ( n =10). 75% of submucous fibrosis samples ( n =12), 75% of verrucous hyperplasias ( n =16), 77% of verrucous carcinomas ( n =13), 81% of well-differentiated squamous cell carcinomas ( n = 26) and 70% of moderate- to poorly-differentiated squamous cell carcinomas ( n =10). In addition, GST pi expression was independent of the state of differentiation of oral cancers. Since GST pi was significantly over-expressed in the oral premalignant and malignant lesions, the kinetics of GST pi-positive cells and the value of GST pi as a tumor marker in oral carcinogenesis need further investigation.     

后牙复合树脂磨耗的临床评价

为探索评价复合树脂磨耗的最佳方法，本研究采用直接临床评价法和间接模型比较法，对以４种复合树脂修复的９３例磨牙面洞修复体进行了３年的评估。结果表明，直接法对修复体早期磨耗的评估不敏感，但对修复体其它方面的评价目前仍为首选；间接法评估修复体的磨耗更准确、敏感，量化的磨耗值便于统计学分析；直接法与间接法相结合可更客观，更全面地评价复合树脂修复体的临床效果。