Nanoparticles can have profound effects on cell biology. Here, we show that after TiO2, SiO2, and hydroxyapatite nanoparticles treatment, TR146 epithelial cell sheet displayed slower migration. Cells after exposure to the nanoparticles showed increased cell contractility with significantly impaired wound healing capability however without any apparent cytotoxicity. We showed the mechanism is through nanoparticle-mediated massive disruption of the intracellular microtubule assembly, thereby triggering a positive feedback that promoted stronger substrate adhesions thus leading to limited cell motility.

Purpose-The aims of this systematic review were to determine, in patients receiving cancer therapy, the prevalence of clinical oral fungal infection and fungal colonization, to determine the impact on quality of life and cost of care, and to review current management strategies for oral fungal infections.Methods-Thirty-nine articles that met the inclusion/exclusion criteria were independently reviewed by two calibrated reviewers, each using a standard form. Information was extracted on a number of variables, including study design, study population, sample size, interventions, blinding, outcome measures, methods, results, and conclusions for each article. Areas of discrepancy between the two reviews were resolved by consensus. Studies were weighted as to the quality of the study design, and recommendations were based on the relative strength of each paper. Statistical analyses were performed to determine the weighted prevalence of clinical oral fungal infection and fungal colonization.Results-For all cancer treatments, the weighted prevalence of clinical oral fungal infection was found to be 7.5% pretreatment, 39.1% during treatment, and 32.6% after the end of cancer therapy. Head and neck radiotherapy and chemotherapy were each independently associated with a significantly increased risk for oral fungal infection. For all cancer treatments, the prevalence of oral colonization with fungal organisms was 48.2% before treatment, 72.2% during treatment, and 70.1% after treatment. The prophylactic use of fluconazole during cancer therapy resulted in a prevalence of clinical fungal infection of 1.9%. No information specific to oral fungal infections was found on quality of life or cost of care.Conclusions-There is an increased risk of clinically significant oral fungal infection during cancer therapy. Systemic antifungals are effective in the prevention of clinical oral fungal infection in patients receiving cancer therapy. Currently available topical antifungal agents are less efficacious, suggesting a need for better topical agents.

IntroductionThis purpose of this systematic review was to evaluate the literature and update our current understanding of the impact of present cancer therapies on the dental apparatus (teeth and periodontium) since the 1989 NIH Development Consensus Conference on the Oral Complications of Cancer Therapies.Review methodA systematic literature search was conducted with assistance from a research librarian in the databases MEDLINE/PubMed and EMBASE for articles published between 1 January 1990 and 31 December 2008. Each study was independently assessed by two reviewers. Taking into account predetermined quality measures, a weighted prevalence was calculated for the prevalence of dental caries, severe gingival disease, and dental infection. Data on DMFT/dmft, DMFS/dmfs, plaque, and gingival indexes were also gathered. The level of evidence, recommendation, and guideline (if possible) were given for published preventive and management strategies.ResultsSixty-four published papers between 1990 and 2008 were reviewed. The weighted overall prevalence of dental caries was 28.1%. The overall DMFT for patients who were post-antineoplastic therapy was 9.19 (SD, 7.98; n = 457). The overall plaque index for patients who were post-antineoplastic therapy was 1.38 (SD, 0.25; n = 189). The GI for patients who were post-chemotherapy was 1.02 (SD, 0.15; n = 162). The weighted prevalence of dental infections/abscess during chemotherapy was reported in three studies and was 5.8%.ConclusionsPatients who were post-radiotherapy had the highest DMFT. The use of fluoride products and chlorhexidine rinses are beneficial in patients who are post-radiotherapy. There continues to be lack of clinical studies on the extent and severity of dental disease that are associated with infectious complications during cancer therapy.

No abstract

This systematic review identified the presence of pain before cancer therapy, likely attributable to the cancer; an increase in pain during therapy and the common persistence of pain following cancer treatment. Continuing research should use validated tools to prospectively assess orofacial pain, its causes and pathophysiology, and its effect on quality of life and economic impact. Clinical trials of pain management in this setting are also warranted.

In view of the low prevalence of infections and the potential for complications after third molar extractions, it is suggested that partial dental evaluation/treatment protocols prior to intensive chemotherapy; whereby minor caries (within dentin), asymptomatic third molars or asymptomatic teeth without excessive probing depth (<8 mm), mobility (mobility I or II) or with periapical lesions of <5 mm were observed; is a viable option when there is insufficient time for complete dental evaluation/treatment protocols. The use of chlorhexidine, fluoride mouth rinses as well as composite resin, resin-modified glass ionomer cement (GIC), and amalgam restorations over conventional GIC in post head and neck radiation patients who are compliant fluoride users is recommended.

Nanomaterials (NMs) such as titanium dioxide (nano-TiO2) and hydroxyapatite (nano-HA) are widely used in food, personal care, and many household products. Due to their extensive usage, the risk of human exposure is increased and may trigger NMs specific biological outcomes as the NMs interface with the cells. However, the interaction of nano-TiO2 and nano-HA with cells, their uptake and subcellular distribution, and the cytotoxic effects are poorly understood. Herein, we characterized and examined the cellular internalization, inflammatory response and cytotoxic effects of nano-TiO2 and nano-HA using TR146 human oral buccal epithelial cells as an in vitro model. We showed both types of NMs were able to bind to the cellular membrane and passage into the cells in a dose dependent manner. Strikingly, both types of NMs exhibited distinct subcellular distribution profile with nano-HA displaying a higher preference to accumulate near the cell membrane compared to nano-TiO2. Exposure to both types of NMs caused an elevated reactive oxygen species (ROS) level and expression of inflammatory transcripts with increasing NMs concentration. Although cells treated with nano-HA induces minimal apoptosis, nano-TiO2 treated samples displayed approximately 28% early apoptosis after 24 h of NMs exposure. We further showed that nano-TiO2 mediated cell death is independent of the classical p53-Bax apoptosis pathway. Our findings provided insights into the potential cellular fates of human oral epithelial cells as they interface with industrial grade nano-HA and nano-TiO2.

No abstract