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1.

Background

This study investigated the correlation between a history of human papillomavirus (HPV) infection and skin cancer risk.

Materials and Methods

The study cohort comprised 26,919 patients with newly diagnosed HPV infection between 2000 and 2012; with the use of computer-generated numbers, patients without previous HPV infection were randomly selected as the comparison cohort. The patients in the HPV infection cohort were matched to comparison individuals at a 1:4 ratio by demographic characteristics and comorbidities. All study individuals were followed up until they developed skin cancer, withdrew from the National Health Insurance program, were lost to follow-up, or until the end of 2013. The primary outcome was subsequent skin cancer development. Cox proportional hazards regression analysis was used to analyze the risk of skin cancer with hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort.

Results

The adjusted HR of skin cancer for patients with HPV relative to controls was 2.45 after adjusting sex, age and comorbidities. (95% CI, 1.44–4.18, p < .01). The subgroup analysis indicated that a patient with HPV infection had a significantly greater risk of skin cancer if they were aged >40 years. Notably, a risk of skin cancer was found in the group diagnosed with HPV within the first 5 years after the index date (adjusted HR, 3.12; with 95% CI, 1.58–5.54). Sensitivity analysis by propensity score, matching with balanced sex, age, and comorbidities, showed consistent results.

Conclusion

A history of HPV infection is associated with the development of subsequent skin cancer in Taiwanese subjects, and the risk wanes 5 years later.

Implications for Practice

In this Taiwan nationwide cohort study, there was a 2.45-fold increased risk of developing new-onset skin cancers for patients with incident human papillomavirus (HPV) infection, compared with the matched controls. Furthermore, the risk was noticeably significant among patients aged >40 years. A prominent risk of skin cancers was found in the group diagnosed with HPV within the first 5 years after the index date in this study. The results of this analysis may raise consensus on the effect of HPV infection on the risk of skin cancers. Clinicians are encouraged to implement prudently on the differential diagnosis of skin cancers and HPV prevention and treatment, especially in older patients.
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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   
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A group of 112 adult females (average age 25.66) and 104 adult males (average age 25.62) were subjected to cephalometric evaluation in their natural head position. No significant differences were found in the nasionsella (SN) plane, Frankfort horizontal (FH) plane or palatal planes between male and female subjects. The SN plane was found to be located at 7.26 degrees above the true horizontal on the average, and the FH plane differed on the average 1.92 degrees from the true horizontal with the line diverging forward and upward. The palatal plane was found to be located in a downward and forward direction at 1.17 degrees from the true horizontal plane on the average. The orbitale (Or) was found to be located at 2.34 mm on the average above the true horizontal plane depicted from the porion (Po) in this study, which implies that the racial characteristic of a high zygomatic bone in Chinese may have some influence upon the position of Or, and this should be taken into consideration when the FH plane is used as the true horizontal during face bow transfer. The mandibular plane (MP) angle, occlusal plane (OP) angle and the gonial angle (GA) of males were found to be smaller than those of females, with a significant difference at the level of P less than 0.001, P less than 0.01 and P less than 0.01, respectively. The upper facial divergent angles of males and females were quite similar, as reflected by the similarity in the SN-FH angles and SN-PP angles between the sexes A significant difference was found to exist in the lower facial divergent angles between males and females. The SN-MP angle, PP-OP angle and PP-MP angle were all significantly smaller in males, with a P less than 0.001. The OP-MP angle was also smaller in males with P less than 0.05.  相似文献   
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The aim of the present study was to evaluate the influence of membrane exposure on guided tissue regeneration (GTR). Thirty patients with 2-wall or 3-wall intraosseous defects were treated with GTR. Periodontal index, gingival index, bleeding on probing, probing depth, clinical attachment level and recession were assessed at the baseline examination, as well as immediately prior to and six months after GTR. The numbers of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans on the retrieved expanded polytetrafluoroethylene (e-PTFE) membranes were assessed using polymerase chain reaction. The results showed that 26.3% of the membrane exposure sites had zero attachment gain. The membrane exposure sites tended to achieve a smaller clinical attachment gain and had significantly greater marginal tissue recession ( p = 0.006). In addition, the exposed membranes harbored significantly more A. actinomycetemcomitans than the non-exposed membranes (p = 0.029). In conclusion, membrane exposure resulted in a poor GTR outcome. The amount of A. actinomycetemcomitans on the exposed membrane may be a major contributing factor to the outcome of GTR.  相似文献   
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Background

Osteochondral allografting is an option for successful treatment of large articular cartilage defects. Use of osteochondral allografting is limited by graft availability, often because of loss of chondrocyte viability during storage.

Questions/purposes

The purpose of this study was to compare osteochondral allografts implanted in canine knees after 28 days or 60 days of storage for (1) initial (1 week) safety and feasibility; (2) integrity and positioning with time (12 weeks and 6 months); and (3) gross, cell viability, histologic, biochemical, and biomechanical characteristics at an endpoint of 6 months.

Methods

With Institutional Animal Care and Use Committee approval, adult dogs (n = 16) were implanted with 8-mm cylindrical osteochondral allografts in the lateral and medial femoral condyles of one knee. Osteochondral allografts preserved for 28 or 60 days using either the current tissue bank standard-of-care (SOC) or a novel system (The Missouri Osteochondral Allograft Preservation System, or MOPS) were used, creating four treatment groups: SOC 28-day, MOPS 28-day, SOC 60-day, and MOPS 60-day. Bacteriologic analysis of tissue culture and media were performed. Dogs were assessed by radiographs and arthroscopy at interim times and by gross, cell viability, histology, biochemistry, and biomechanical testing at the 6-month endpoint.

Results

With the numbers available, there was no difference in infection frequency during storage (5% for SOC and 3% for MOPS; p = 0.5). No infected graft was implanted and no infections occurred in vivo. MOPS grafts had greater chondrocyte viability at Day 60 (90% versus 53%; p = 0.002). For 60-day storage, MOPS grafts were as good as or better than SOC grafts with respect to all outcome measures assessed 6 months after implantation.

Conclusions

Donor chondrocyte viability is important for osteochondral allograft success. MOPS allows preservation of chondrocyte viability for up to 60 days at sufficient levels to result in successful outcomes in a canine model of large femoral condylar articular defects.

Clinical Relevance

These findings provide a promising development in osteochondral allograft technology that can benefit the quantity of grafts available for use and the quality of grafts being implanted.  相似文献   
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