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The branch of Prosthodontics is not only a science but also an art of handling patients who present with limitations in continuing with normal procedures. An abnormally small mouth opening is called as microstomia. The common reasons for this condition include scleroderma, orofacial malignancies, surgery, burns and TMJ ankylosis. Impressions can be made for patients with restricted mouth opening with a sectional impression tray that can be assembled and disassembled in the mouth and reassembled outside the mouth. This article describes a sectional tray system for making preliminary and secondary impressions. Also an innovative technique of fabricating a sectional complete denture for a microstomic patient has been described.

Aim: This study aims to evaluate and compare the shear bond strength (SBS) of three different resin cements - total etch and rinse, self-etch and self-adhesive resin cements, used to bond the lithium disilicate restorations to human dentin. Settings and Design: Comparative - Invitro study design. Materials and Methods: Forty-five lithium disilicate (IPS E.max) discs (4 mm in diameter and 3 mm thick) were fabricated and randomly divided into three groups ( n = 15). The occlusal surfaces of 45 extracted human maxillary premolars were ground flat. Fifteen specimens were luted, under a constant load, with each of the following resin cement: Variolink N (Group VN), Multilink N (Group MN), and Multilink Speed (Group MS). All cemented specimens were stored in distilled water for 1-week following which, they were tested under shear loading at a constant crosshead speed of 1 mm/min until fracture on a universal testing machine; the load at fracture was reported in megapascals (MPa) as the bond strength. Fractured specimens were also inspected by the scanning electron microscopy. Statistical analysis of the collected data was performed using one-way ANOVA test, post hoc Bonferroni test, and Chi-square test (α =0.05). Statistical Analysis Used: Oneway ANOVA test and post hoc Bonferroni test. Results: Mean SBS data of the groups in MPa were: Variolink N (Group VN): 14.19 ± 0.76; Multilink N (Group MN): 10.702 ± 0.75; and Multilink Speed (Group MS): 5.462 ± 0.66. Significant differences in SBS ( P < 0.001) of the three resin cement were found. Intergroup comparison revealed statistically significant differences in SBS between Groups VN and MN ( P < 0.001), Groups B and C ( P < 0.001), and Groups VN and MS ( P < 0.001). Chi-square test used to compare the distribution of mode of bond failure among the three groups delineated that the cohesive failure was significantly more among Group VN, whereas adhesive failure was significantly more among Group MN and MS. Conclusion: Total etch and rinse resin cement, i.e., Variolink N (Group VN) produced significantly higher bond strength of all-ceramics to dentin surfaces than did the self-etch and self-adhesive resin cements, i.e., Multilink N and Multilink Speed, respectively.

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