Rehabilitation of a Head and Neck Cancer Survivor With a Functionally and Biomechanically Challenged Dentition.

Radiation therapy for patients with head and neck cancer can have damaging effects on oral health, including reduced salivary flow. In this case report, a 58-year-old patient had previously undergone radiation therapy for stage II squamous cell carcinoma of the larynx. Symptoms of xerostomia persisted, and her dentition suffered as a result. Problems included moderate to severe loss of tooth structure; erosive pitting lesions on the cusp tips of posterior teeth; and attrition throughout her dentition, particularly in the anterior. To achieve the esthetic, functional, and biomechanical goals of the case, treatment involved the use of both full-coverage, cohesively retained restorations and feldspathic veneers, depending on the amount of adequate enamel available for adhesion, along with limited orthodontic therapy. Additionally, the patient was instructed on how to stimulate salivary flow post-treatment.

A Comparative Study of the Accuracy of Dies Made from Digital Intraoral Scanning vs. Elastic Impressions: An In Vitro Study.

PURPOSE: To compare the dimensional accuracy of dies generated from digital intraoral scans with dies generated from conventional polyvinyl siloxane (PVS) impression material. MATERIALS AND METHODS: A machined metal die was impressed 10 times using PVS, and scanned 10 times using the iTero Cadent system and 10 times using the LAVA C.O.S. system. Dies generated from each system were imaged in a standardized holder using a microscope and measured with analytical software at three sites and compared with the dimensions of the master die. RESULTS: The dimensional differences between the master die and both the PVS and iTero groups were approximately 60 µm in all three dimensions but the Lava C.O.S. die dimensions measured close to 100 µm at two of the three sites. CONCLUSION: PVS/Die and iTero groups offered superior reproduction of the master die in terms of dimensional accuracy, but these differences are likely of little clinical significance.

Dental implants in the patient with multiple myeloma: Literature review and case report.

Multiple myeloma is a blood dyscrasia involving plasma cells in the bone marrow. Much new information and many management strategies exist for these disorders. For dental care, there are a number of issues for the clinician to consider. This review discusses current management of this disease and a case report.

Correlation of plasma FL expression with bone marrow irradiation dose.

PURPOSE: Ablative bone marrow irradiation is an integral part of hematopoietic stem cell transplantation. These treatment regimens are based on classically held models of radiation dose and the bone marrow response. Flt-3 ligand (FL) has been suggested as a marker of hematopoiesis and bone marrow status but the kinetics of its response to bone marrow irradiation has yet to be fully characterized. In the current study, we examine plasma FL response to total body and partial body irradiation in mice and its relationship with irradiation dose, time of collection and pattern of bone marrow exposure. MATERIALS/METHODS: C57BL6 mice received a single whole body or partial body irradiation dose of 1-8 Gy. Plasma was collected by mandibular or cardiac puncture at 24, 48 and 72 hr post-irradiation as well as 1-3 weeks post-irradiation. FL levels were determined via ELISA assay and used to generate two models: a linear regression model and a gated values model correlating plasma FL levels with radiation dose. RESULTS: At all doses between 1-8 Gy, plasma FL levels were greater than control and the level of FL increased proportionally to the total body irradiation dose. Differences in FL levels were statistically significant at each dose and at all time points. Partial body irradiation of the trunk areas, encompassing the bulk of the hematopoietically active bone marrow, resulted in significantly increased FL levels over control but irradiation of only the head or extremities did not. FL levels were used to generate a dose prediction model for total body irradiation. In a blinded study, the model differentiated mice into dose received cohorts of 1, 4 or 8 Gy based on plasma FL levels at 24 or 72 hrs post-irradiation. CONCLUSION: Our findings indicate that plasma FL levels might be used as a marker of hematopoietically active bone marrow and radiation exposure in mice.

High throughput evaluation of gamma-H2AX.

The DNA double-strand break (DSB) is the primary lethal lesion after therapeutic radiation. Thus, the development of assays to detect and to quantitate these lesions could have broad preclinical and clinical impact. Phosphorylation of histone H2AX to form gamma-H2AX is a known marker for irradiation-induced DNA DSBs. However, the first generation assay involves the use of immunofluorescent staining of gamma-H2AX foci. This assay is time consuming, operator dependent and is not scalable for high throughput assay development. Thus, we sought to develop a new assay using a high throughput electrochemiluminescent platform from Mesoscale Discovery Systems to quantify gamma-H2AX levels. The results show that our assay utilizes significantly less time and labor, has greater intra-assay reproducibility and has a greater dynamic range of gamma-H2AX versus irradiation dose.