Aims and Objectives:To determine the time dependent accuracy of casts made from three different irreversible hydrocolloids.Materials and Methods:The effect of delayed pouring on the accuracy of three different irreversible hydrocolloid impression materials – Regular set CA 37(Cavex, The Netherlands), regular set chromatic (Jeltrate, Dentsply), and fast set (Hydrogum soft, Zhermack Clinical) was investigated. A brass master die that contained two identical posts simulating two complete crown-tapered abutment preparations with reference grooves served as a standardized master model. A total of 120 impressions were made using specially prepared stock-perforated brass tray with 40 impressions of each material. The impressions were further sub-grouped according to four different storage time intervals: 0 min (immediately), 12 min, 30 min, and 1 h. The impressions were stored at room temperature in a zip-lock plastic bag. Interabutment and intraabutment distances were measured in the recovered stone dies (Type IV, Kalrock) using a profile projector with an accuracy of 0.001 mm. The data so obtained was analyzed statistically.Results:Results of this study showed no statistically significant differences in the accuracy of casts obtained at different time intervals.Conclusion:Because it is not always possible to pour the impression immediately in routine clinical practice, all irreversible hydrocolloid materials studied could be stored in a zip-lock plastic bag for upto 1 h without any significant distortion.

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In recent years, radiation therapy has been used with increasing frequency in the management of neoplasms of the head and neck region. Brachytherapy is a method of radiation treatment in which sealed radioactive sources are used to deliver the dose a short distance by interstitial (direct insertion into tissue), intracavitary (placement within a cavity) or surface application (molds). Mold brachytherapy is radiation delivered via a custom-fabricated carriers, designed to provide a more constant and reproducible geometry for source positioning. Radiation carriers are customized to fit the patient in a comfortable, stable, and retentive manner to ensure maximal therapeutic radiations to the desired location and in addition sparing the normal surrounding tissues due to rapid fall-off radioactivity thus minimizing postreatment sequelae of irradiation. This clinical report describes a method of fabrication of a customized radiation carrier or mold for a patient suffering from squamous cell carcinoma of right ring finger, planned to undergo brachytherapy (surface mold therapy). This paper highlights the role and responsibility of the prosthodontist in fabricating the carrier and to maintain the predetermined position of the hollow tubes (catheters) within the mold to remain in the exact position as determined by the radiation oncologist for required results.

Retention in mandibular dentures has always been a challenge for the Prosthodontist and this situation worsens in patients with resorbed ridges. Denture adhesives are known to improve the adhesive bond between the denture and the underlying tissues. But still biocompatibility issues have been noticed from zinc containing denture adhesives in various studies and they recommended using zinc free denture adhesives. However, zinc free denture adhesives still remain unexplored and not much is known about the efficacy of these materials in mandibular dentures especially in patients with poor foundations. The present study was carried out to compare the efficacy of three different commercially available zinc free denture adhesives in relation to their retentive ability in patients with well formed mandibular ridges and in patients with resorbed mandibular ridges. Thirty edentulous patients were selected and the patients were divided into 2 groups; group A comprised of 15 patients with well formed mandibular ridges and group B consisted of 15 patients having resorbed mandibular ridges. The adhesion and cohesion that developed between the dentures and the underlying tissues with and without denture adhesives was evaluated with the help of a force gauge test apparatus in newtons at three different times of adaptation period. Zinc free denture adhesives significantly improved the retention of mandibular complete dentures not only in case of well-formed residual ridges but also resorbed ridges. Use of zinc free denture adhesive led to a higher value of retention as opposed to when the dentures were used without adhesives at all time intervals of adaptation period. Poligrip adhesive was the most effective among all three adhesives used in the study, while Secure was intermediate and Fixon Supergrip was least effective.