Does smoking cessation affect postoperative healing following oral surgery among smokers? - a systematic review.

BACKGROUND: It is well documented that smokers suffer increased risk of postoperative complications after medical surgery, for example delayed healing and increased risk of infection. It is also known that preoperative smoking cessation can reduce the risk of these complications. Because of this there are guidelines regarding preoperative smoking cessation in non-oral medical surgery. There are however no specific guidelines regarding oral surgical procedures, such as surgical extractions, dentoalveolar surgery, periodontal surgery, or dental implantation. Nevertheless, it is common that dentists and oral surgeons recommend smoking cessation pre to oral surgical procedures. The aim with this systematic review was to see if there are any evidence in the literature, supporting preoperative smoking cessation in oral surgical procedures. METHODS: A systematic search of the electronic databases PubMed, Scopus, Web of Science, and Cochrane was conducted to identify studies addressing the effect of preoperative smoking cessation in oral surgical procedures. Included publications were subjected to preidentified inclusion criterion. Six examiners performed the eligibility and quality assessment of relevant studies. Risk of bias was assessed using ROBINS-I and RoB 2. Certainty assessment was carried out using GRADE. RESULTS: The initial search resulted in 2255 records, and after removal of 148 duplicates, 16 articles met an acceptable level of relevance. These were read in full text, whereof 12 articles were excluded, due to different intervention, outcome, or study design than stated in the review protocol. One study remained with moderate risk of bias and three were excluded due to high risk of bias. CONCLUSION: This systematic review could not determine the effect of smoking cessation pre to oral surgical procedures, in smokers. This indicates lack of knowledge in the effects of smoking cessation. We also conclude a lack of knowledge in how to design smoking cessation in the most effective way.

Hazard assessment of hexagonal boron nitride and hexagonal boron nitride reinforced thermoplastic polyurethane composites using human skin and lung cells.

Hexagonal boron nitride (hBN) is an emerging two-dimensional material attracting considerable attention in the industrial sector given its innovative physicochemical properties. Potential risks are associated mainly with occupational exposure where inhalation and skin contact are the most relevant exposure routes for workers. Here we aimed at characterizing the effects induced by composites of thermoplastic polyurethane (TPU) and hBN, using immortalized HaCaT skin keratinocytes and BEAS-2B bronchial epithelial cells. The composite was abraded using a Taber® rotary abraser and abraded TPU and TPU-hBN were also subjected to photo-Fenton-mediated degradation mimicking potential weathering across the product life cycle. Cells were exposed to the materials for 24 h (acute exposure) or twice per week for 4 weeks (chronic exposure) and evaluated with respect to material internalization, cytotoxicity, and proinflammatory cytokine secretion. Additionally, comprehensive mass spectrometry-based proteomics and metabolomics (secretomics) analyses were performed. Overall, despite evidence of cellular uptake of the material, no significant cellular and/or protein expression profiles alterations were observed after acute or chronic exposure of HaCaT or BEAS-2B cells, identifying only few pro-inflammatory proteins. Similar results were obtained for the degraded materials. These results support the determination of hazard profiles associated with cutaneous and pulmonary hBN-reinforced polymer composites exposure.