Gingival retraction is essential to get a dry and debris free field, which enables the impression material to flow into the gingival sulcus and record the area apical to the finish line. Effective gingival retraction without damaging periodontal tissue is extremely important.
UNASSIGNED: To comparatively evaluate the amount of inflammation, as assessed by TNF-α in GCF induced by three different gingival retraction techniques.
UNASSIGNED: Ten patients with a minimum of three teeth that required biomechanical preparation for fixed prostheses and acceptable oral hygiene with no periodontal pathology were included. The patients each received an oral prophylaxis. After a washout period of 10 days patients with gingival index scores of 0 or 1 were included. Measurements of TNF-α was done at baseline, after 30 min, after 7 days and after 28 days using ELISA test kit specific to TNF-α.
UNASSIGNED: The sample population for whom Magic Foam cord was used showed a massive reduction in the amount of TNF -α, from 78% at 7 days to 18.6% at 28 days. There was a reduction in the percentage of TNF -α produced in the samples where normal knitted cord was used and for those where Expasyl was used from 95% to 64.2% and from 70% to 48.3% respectively.
UNASSIGNED: Maximum amount of inflammatory response was seen with plain knitted gingival retraction cord. This was followed by Expasyl gingival retraction system and the least amount of inflammatory cytokine was recorded with Magic Foam retraction cord.

We evaluated the basic characteristics and efficacy of our newly developed patient fixation system for head and neck radiotherapy that uses a dedicated mouthpiece and dental impression materials. The present investigation demonstrated that with this system, the changes in the absorbed dose to water depending on the material of the mouthpiece were small, with a maximum of 0.32% for a 10-MV photon beam. For the dental impression material, we selected a silicone material with the lowest Hounsfield unit (HU) value that had little effect on the generation of artifacts and the quality of the X-ray beam. Multiphase magnetic resonance imaging (MRI) revealed that the head-up and -down motions in the thermoplastic shell without the mouthpiece were 5.76 ± 1.54 mm, whereas the motion with the mouthpiece decreased significantly to 1.72 ± 0.92 mm (P = 0.006). Similarly, the head-left and -right motion displacement decreased from 6.32 ± 1.86 mm without the mouthpiece to 1.80 ± 0.42 mm with the mouthpiece (P = 0.003). Regarding the tongue depressor function of the mouthpiece, the median distance from the hard palate to the surface of the tongue was 28.42 mm. The present results indicate that the new immobilization device developed herein that uses a mouthpiece and a thermoplastic shell is useful for suppressing patients\' head motions and tongue positions.

Surgical procedures in posterior area of maxillary might cause an oroantral communication and iatrogenic sinusitis. An undetected oroantral communication can cause the penetration of foreign bodies, such as dental impression materials, in the maxillary sinus, thereby contributing to persistent sinusitis. Given the occurrence of a very rare clinical and medicolegal case of persistent and drug-resistant sinusitis due to radiologically undetected fragments of silicone paste for dental impression in the maxillary antrum, a literature review was pursued through sensitive keywords in relevant databases for health sciences. All retrieved articles were considered and data about the kind of impression materials thrusted into the maxillary sinus, the diagnostic issues, the reported range of symptoms, and the occurrence of medicolegal issues were analyzed. The diagnosis resulted to be quite challenging and belatedly especially in case of healed oroantral communication and when the material retained in the maxillary sinus has similar radiodensity compared to the surrounding normal or inflammatory tissues. The case was then discussed in comparison with the reviewed literature for both clinical and medicolegal issues. Hints were provided to professionals to face the challenging diagnosis in similar rare cases and to avoid the possible related litigation.

OBJECTIVE: This study compares standard commercial bolus material (Superflab) to custom prepared silicone dental impression material (CDIM) and play dough material (PDM) with respect to dosimetric properties and applicability by using ion chamber measurement and calculated dose values.
METHODS: The CDIM bolus was prepared by mixing dental impression silicone material with enough water to maintain a density of about 1.0 g/cm3. The prepared bolus material is applied on an RW3 solid phantom by covering 10x10 cm2 area with 0.5-1 cm thickness. Ion chamber measurements were performed separately with and without bolus material application. The setup was scanned in CT and the same procedure was repeated in the TPS using the scan data, in which the Pencil Beam Convolution dose calculation algorithm was used. To compare the effect of bolus material on tissue, the Superflab bolus and CDIM bolus were applied with 1 cm of thickness on postmastectomy scar and dose calculations on TPS were performed.
RESULTS: After comparison of the dosimetric values for Superflab, CDIM and PDM, we obtained statistically meaningful results between superflab and CDIM. For PDM, the results obtained with TPS and ion chamber measurements indicated that, it is not suitable to use in radiotherapy application due to its material properties. For the simulated skin dose values obtained at five random points on the scar tissue, the comparison of Superflab and CDIM TPS calculation results were not statistically significant.
CONCLUSIONS: The CDIM is easy to prepare and apply on irregular mastectomy scar tissue and it prevents formation of air gaps in the application surface. Especially for curved anatomical regions such as scar tissue, inclusion of the bolus material in treatment planning protocol will reduce dose uncertainty in application. It is safe to use CDIM as an alternative to Superflab in radiotherapy application, whereas PDM is not useful in clinical practice due to its material properties.

The aim of this study was to compare the effect of several commercially available disinfectants on the accuracy of various types of impression materials and their compatibility with gypsum including surface quality and structure evaluation. Four alginate and three elastomeric impression materials in combination with disinfectants Aseptoprint Liquid, Zeta 7 solution, Silosept and Dentaclean Form were tested. The dimensional changes, detail reproduction, the compatibility with gypsum and surface/subsurface morphology were evaluated using light microscopy, scanning electron microscopy and micro computed tomography. Two alginate materials disinfected in Dentaclean Form exhibited the most significant differences (p<0.0001). The loss of detail on some alginate impressions in combination with this disinfectant including deterioration and change of morphology of gypsum surfaces was observed. Porosity in subsurface area and exposed large particles were detected. It was confirmed that the desired properties of impressions may be negatively affected in combination with some disinfectants.