Objective: Elastic impression materials considered favourable decision in fixed and removable prosthesis due to ease of use and accuracy. High price tag is the main drawback. The purpose of this study was to evaluate surface detail reproduction and dimensional stability of newly introduced 3M Preliminary PentaTM VPS in comparison to other elastic impression.           Methods: Alginate, alginate replacement and 3M light body were tested for surface detail reproduction and dimensional stability. Ten samples were prepared for each using a stainless-steel die that was created according to ADA specification No. 18 and 19. Surface detail was assessed directly after setting while dimensional stability was evaluated immediately and 24hr after. The data were analysed using a paired sample t-test. Results: All the samples were able to record 75μm line for surface detail. Surface record of 3M imprintTM 4 Preliminary PentaTM VPS showed a similar result to light body. While alginate failed to reproduce 50μm and 20μm lines. Regards to dimensional stability, light body resisted change with respect to time. In contrast, alginate revealed a significant effect (p˂0.05) on dimensional stability for the same storage period while not a major effect was observed for alginate replacement.  Conclusions: Within the limitations of this study, it can be concluded that light body underwent less dimensional change than alginate and alginate replacement. It also revealed a better replication of details. Alginate replacement was more stable during the storage period with better surface detail record than alginate.

Backgrounds and objectives: Dental impressions present a risk to spread infections among dental practitioners and should be disinfected to prevent the spread of these microorganisms. Different disinfectant materials and techniques can be used to eliminate this threat. The purpose of this study was to evaluate the effect of some disinfectant materials with two different techniques on surface detail and dimensional stability of elastomeric impression materials. Materials and methods: Three dental impression materials were used in this study, Vinyl polysiloxane, Polyether and Vinyl polyether siloxane that were disinfected with sodium hypochlorite, Dettol and Cavex Impresafe by using two techniques, spraying and immersion methods for each. Results: The results of this study showed a significant difference of the dimensions between immediate and 48 hours after disinfection P<0.05 with the maximum change (1.5%) appeared with vinyl polysiloxane material when immersed in sodium hypochlorite for 10 minutes and stored for 48 hours, but this change was acceptable by the ADA. Polyether showed the least dimensional change of 0.05% after 7 hours from disinfection with Cavex impresafe and the latter caused the least change on the impression materials. Conclusion: Within the limitations of this in vitro study, it was concluded that dental impression materials can be disinfected without causing dimensional changes that affect the manufacture of dental prosthesis.

The clinical life of a maxillofacial prosthesis averages about six months before it needs to be re-fabricated. Most of maxillofacial prosthesis attached to the acrylic resin via adhesive primers detached and have to be re-attached every few months. This in vitro study established to evaluate the effect of adding calcium carbonate nanoparticles at different concentrations on the bonding strength of maxillofacial silicone elastomer to the acrylic resin, before and after accelerated aging. Seventy samples were prepared, ten samples per each group. Each silicone sample sandwiched between two strips of acrylic resin via A-330-G adhesive primer. From each group five samples were undergoing accelerated aging. All samples were tested for shear bond strength by using Instron testing machine. Calcium carbonate nanoparticles have a significant effect on the shear bond strength of maxillofacial silicone to the acrylic resin and the groups that contain the lowest concentrations of calcium carbonate nanoparticles showed the most significant changes. It CaCO3 nanoparticles in trace amount can improve the shear bond strength of maxillofacial silicone elastomer to the acrylic resin after subjecting to accelerated aging.

Objectives: In recent years, one-piece dental implants are widely used to replace missing teeth as the technique is minimally invasive, and its special design offers to be used in an atrophied and narrow bone. Few pieces of literature were found regarding the use of these dental implants in the esthetic zone. This study aimed to evaluate the esthetic satisfaction of patients treated with one-piece dental implants in the esthetic zone using a special technique to enhance gingival recontouring and provide an optimum emergence profile.           Methods: Twenty patients with single missing maxillary or mandibular teeth were enrolled in the study (25-50 year age group). They were treated by one-piece dental implants performing the flapless technique; a flame-shaped bur was used to create a sulcus around the implant abutment; the sulcus was then filled with flowable composite resin and allowed for seven days to recontour the gingival tissue. Esthetic satisfactions of the patients were evaluated two weeks and six months after the placement of the permanent crown using subjective and objective methods.       Results: The esthetic assessment after 14 days and after six months using the objective method Pink Esthetic Score / White Esthetic Score (PES / WES) index showed that 85% to 90% of the cases received PES and WES mean values of 6 or more, which is the threshold of clinical acceptability. Regarding the subjective method using the Visual Analogue Scale (VAS) index. After 14 days, the total means value for all the questions was (7.19), and the results after six months were (7.25). There was a statistically non-significant difference between the two-time intervals in both objective and subjective methods (P< 0.05).   Conclusions: It has been concluded that one-piece dental implants can be successfully used in the esthetic zone after the special gingival recontouring technique.