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Parotid lymph node (PLN) metastasis greatly worsens the prognosis of patients with oral squamous cell carcinoma (OSCC) and poses a great challenge for further treatment of OSCC. The clinicopathological characteristics and treatment strategies for PLN metastasis from OSCC need to be comprehensively elucidated. A retrospective review of OSCC patients who experienced postoperative PLN metastasis in our department between 2000 and 2018 was performed in this study. A total of 47 OSCC patients with postoperative PLN metastasis were identified. PLN with metastasis were divided into three groups based on the location: parotid tail (PLN-t), superficial lobe (PLN-sl), and deep lobe (PLN-dl). Most of the patients experienced PLN metastasis within less than 12 months after the primary surgery for OSCC. Comparatively, patients with PLN-sl metastasis were more prone to have infiltration of the facial nerve. The tongue and buccal mucosa were the most frequent primary sites associated with PLN metastasis from OSCC. PLNs in the parotid tail were most commonly affected by the metastasized OSCC. Consequently, we recommend a series of strategies for the prevention and treatment of PLN metastasis for OSCC patients. In conclusion, PLNs should not be overlooked during preoperative evaluation and postoperative follow-up examinations for OSCC patients.  相似文献   
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The objective of this study was to compare the implant longevity following two methods of peri-implant soft tissue optimization following free fibula flap (FFF): thinning of skin paddle (SP) and collagen matrix (CM). All patients who underwent rehabilitation with dental implants after mandibular reconstruction with FFF between June 2009 to May 2014 were retrospectively reviewed. Two methods of peri-implant soft tissue optimization were applied: (1) SP group, (2) CM group. Outcome measurements were: modified plaque index (mPI), modified sulcus bleeding index (mSBI), probing depth (PD), marginal bone loss (MBL), implant success rate and complication rates. A total of 24 patients with 69 implants were included in the study, with 8.7% (n = 6) of implants lost in 3 years. No statistically significant difference was found regarding the outcome measurements in both groups. Failed implants presented with statistically significant higher mPI, mSBI, PD and MBL scores during prosthesis delivery and subsequent follow-ups (P<0.03). In the SP group, one patient experienced SP necrosis which later underwent soft tissue optimization using CM. CM is an alternative peri-implant soft tissue, while thinning of SP is feasible if thickness is well controlled.  相似文献   
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Background

Prohibition of tobacco sales to minors is a provision of the World Health Organization Framework Convention on tobacco control. This measure is effective to reduce youth tobacco use, if the legislation adopted is properly implemented and enforced. Through the examples of France and Quebec, the objective of this study is to compare legislative frameworks prohibiting tobacco sales to minors, their enforcement, and possible impact on underage smoking.

Methods

Identification of legislative instruments, reports from public health authorities, and articles addressing the focused question was performed trough Medline and Google.

Results

Selling tobacco products to minors under 18 years of age has been banned by the law since 1998 in Quebec and 2009 in France. In 2011, in France for individuals aged 17, compliance with the law was 15%. In 2017 in France, 94% of 17-year-old daily smokers regularly bought their cigarettes in a tobacco store. Law enforcement controls and sanctions are non-existent. In 2013 in Quebec, 23% of underage smoking students usually bought their own cigarettes in a business. The compliance rate with the prohibition law rose from 37% in 2003 to 92.6% in 2017. An approach of underage “mystery shoppers” attempting to purchase tobacco products and dedicated inspectors has been implemented, and progressive sanctions are applied in case of non-compliance. In 2013, 12.2% of Quebec high school students and, in 2017, 34.1% of French 17 year olds reported using tobacco products in the last 30 days.

Conclusion

Only an improved law enforcement, through the training of tobacco retailer's, inspections and effective deterrent penalties for non-compliance, leads to an effective legislative measure in terms of public health.  相似文献   
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