Purpose: This in vitro study assessed the color of computer-aided design/computer-aided manufacturing (CAD/CAM) reinforced composite material (BRILLIANT Crios) under different shades of tooth substrates. Materials and methods: Around 21 rectangular BRILLIANT Crios slices (A3 HT, 12 × 10 × 1 mm) and 21 composite resin samples (IPS Natural Die Material; 12 × 10 × 2.5 mm) with three different shades (ND3, ND5, and ND7) were prepared. Baseline color measurements (L*, a*, b*) were obtained using a spectrophotometer. Each slice was then cemented to a composite resin sample with self-adhesive transparent dual-cure resin cement (SpeedCEM®Plus) and designated as group I (ND3), group II (ND5), and group III (ND7). Final color measurements were taken, and the color difference (ΔEab*) was calculated. Data were analyzed using analysis of variance (ANOVA) followed by post hoc Tukey's test for multiple comparisons. Results: Different shades of substrate significantly affected ΔEab (p < 0.001). Group III (ND7) (4.18 ± 0.15) exhibited the highest ΔE value, while group I (ND3) (2.95 ± 0.11) demonstrated the lowest ΔE value. Groups I (ND3) (−1.83 ± 0.13) and group III (ND7) (−2.11 ± 0.15) exhibited higher ΔL compared to group II (ND5). Group I (ND3) exhibited the highest Δa value (0.85 ± 0.07), while group II (ND5) displayed the lowest (0.77 ± 0.11). The post hoc test showed a significant difference between the groups compared for ΔE, ΔL, and Δa values. Concerning Δb, group III (3.45 ± 0.17) had a higher value while group I (2.15 ± 0.17) had the lowest, while group II (2.97 ± 0.16) revealed an insignificant difference with other groups. Conclusion: Color change (ΔE) of group I (ND3) and group II (ND5) was clinically acceptable while that of group III (ND7) was unacceptable. The resulting optical color of CAD/CAM BRILLIANT Crios was greatly influenced by the color of the underlying tooth substrate. The darker the shade of the tooth substrate, the less ability of the BRILLIANT Crios to mask the darker shade. For patients with deeply discolored teeth and requiring esthetic restoration, it's recommended to use high-opacity ceramic material rather than indirect composite material.

Purpose: To evaluate the color stability and surface roughness of PEEK after immersion in 10% povidone-iodine, 4% chlorhexidine gluconate, 2% glutaraldehyde, 5% sodium hypochlorite, and neutral soap disinfectant solutions. Materials and methods: A total of 40 polyetheretherketone (PEEK) disk-shaped samples of diameter 10 and 3 mm thickness [according to International Organization for Standardization (ISO) 7491:2020] were sectioned and immersed in the disinfectant solution for 30 days for 10 minutes, twice a day. The disinfectant solutions included were 10% povidone-iodine, 4% chlorhexidine gluconate, 2% glutaraldehyde, 5% sodium hypochlorite, and neutral soap solution. Color stability was measured using a calorimeter after 30 days, and surface roughness was evaluated using a surface roughness tester. The color stability and surface roughness values were statistically analyzed using one-way analysis of variance (ANOVA) and Tukey's post hoc test. Results: The mean color stability (ΔE) of PEEK after disinfection with neutral soap, 4% chlorhexidine gluconate, 5% sodium hypochlorite, 10% povidone-iodine, and 2% glutaraldehyde were 1.286 ± 0.208, 1.156 ± 0.261, 2.965 ± 0.292, 0.729 ± 0.309, and 0.601 ± 0.246, respectively, and the difference is statistically significant (p = 0.001). The post hoc test showed a significant difference in color change between different disinfectants except for chlorhexidine-neutral soap solution (p = 0.863) and glutaraldehyde-povidone-iodine (p = 0.871). The surface roughness of the control, chlorhexidine gluconate, sodium hypochlorite, neutral soap solution, povidone-iodine, and glutaraldehyde were 0.084 ± 0.026, 0.176 ± 0.080, 0.138 ± 0.064, 0.092 ±0.025, 0.086 ±0.033, and 0.095 ±0.032 µm, respectively, where p >0.05 for all group comparison except between chlorhexidine with neutral soap, glutaraldehyde, and sodium hypochlorite. Conclusion: Polyetheretherketone materials immersed in 5% sodium hypochlorite showed increased color change, while the least change was observed with 2% glutaraldehyde. Around 4% chlorhexidine gluconate produced more surface roughness. Hence, 2% glutaraldehyde is recommended as a disinfectant for PEEK-based prostheses, and immersion of PEEK prosthesis in 5% sodium hypochlorite solution should be avoided.

Purpose: The purpose of this in vitro study was to compare the efficacy of bonding 5-mol% yttria-stabilized tetragonal zirconia polycrystal (5Y-PSZ) zirconia (Zr) to enamel relative to lithium (Li) disilicate glass-ceramic. Materials and methods: A total of 36 disk-shaped samples (4 × 2 mm²) were produced by milling process from two groups—Li disilicate (Li group) (IPS e.max CAD, n = 18) and 5Y-PSZ (Zr group) [KATANA Ultra-Translucent Multi-layered (UTML), (n = 18)]. All samples were subjected to a surface conditioning protocol for optimal bonding with a total-etch methacryloyloxydecyl dihydrogen phosphate (MDP) containing adhesive resin cement (Variolink Esthetic DC). Subsequently, a shear bond strength test was performed. The evaluation of failure modes and analysis of the surface was conducted using a light microscope. Failure modes were categorized into adhesive, cohesive, and mixed. The Mann–Whitney U test was utilized to assess statistically significant differences between the two groups. Qualitative data were presented as frequencies and percentages. The Chi-squared test was utilized for all comparative analyses. Results: There was no statistically significant difference in shear bond strength between the two groups (36.57 ± 30.81 MPa for the Li group and 34.11 ± 22.88 MPa for the Zr group). The failure modes varied between adhesive (40, 50%), mixed (30, 40%), and cohesive (30, 10%) in the Li and Zr groups, respectively, with insignificant differences between them (p = 0.53). Conclusion: A 5-mol% yttria-stabilized tetragonal Zr polycrystal showed high shear bond strength similar to Li disilicate glass-ceramic. Air blasting of Zr followed by primers and resin cements based on 10-MDP monomer has proven its efficiency in Zr-resin bonding. Both ultra-translucent 5Y-PSZ Zr and Li disilicate offer viable options for esthetic restorations on anterior teeth.

Purpose: To assess the effect of an edentulous state on sleep quality in the elderly. Materials and methods: A case–control study was carried out in which a total of 100 elderly individuals aged over 60 years were enrolled. Of these, 50 were edentulous and comprised the case group, while 50 age-matched dentulous elderly individuals comprised the control group. Body mass index (BMI), medical history, activity level, and personal habit profiles of both groups were noted. Sleep quality assessment was done using the Pittsburgh Sleep Quality Index (PSQI). PSQI scores greater than five were considered indicators of poor sleep quality. Chi-squared and independent samples ”t-tests” were used for univariate analysis. Linear regression was performed for multivariate analysis. Results: The mean age of cases was 68.82 ± 5.20 years (range 61–78). The majority of cases were females (56%). Cases had a significantly higher mean BMI and proportion of those with a sedentary activity profile compared to controls. The maximum number of cases had been in an edentulous state for <6 months (42%). The mean sleep quality scores for PSQI domains, including latency, duration, subjective sleep quality, daytime dysfunction, and habitual, were significantly higher in cases compared to controls. The overall mean total PSQI score was 13.50 ± 2.92 in cases compared to 6.99 ± 2.05 in controls (p < 0.001). The majority of cases had moderate-to-severe sleep disturbance (88%) compared to only 1 (2%) of controls (p < 0.001). On linear regression for PSQI scores, only age and edentulous state emerged as independent significant factors associated with PSQI scores (p < 0.05). Conclusion: Edentulous state contributes to poor sleep quality in elderly patients. Interventions to improve sleep quality in elderly patients with an edentulous state should be done.

Purpose: To compare the fracture resistance of endodontically treated premolars reinforced by one or two fiber-reinforced composites and different core buildup materials. Materials and methods: A total of 40 double-rooted maxillary premolars were collected and divided into four groups (n = 10/group). After endodontic treatment, the teeth were prepared and received fiber posts as follows: group I—single fiber post with LuxaCore Z as luting cement and core buildup material, group II—two fiber posts with LuxaCore Z as luting cement and core buildup material, group III—single fiber post cemented with RelyX Unicem followed by packable composite as a core buildup material, group IV—two fiber posts cemented with RelyX Unicem followed by packable composite as a core buildup material. The specimens were placed in the universal testing machine for testing of the fracture resistance. Specimens were axially loaded on the center of the occlusal surface. One-way analysis of variance (ANOVA) was done to assess group differences, followed by Tukey's honestly significant difference (HSD) post hoc test for multiple comparisons. Results: Group IV (two fiber posts with resin cement and packable composite resin) had a significantly higher mean fracture resistance (1049.16 ± 125.51 N) compared to group I (874.47 ± 59.94 N), group II (872.16 ± 151.18 N), and group III (979.21 ± 117.45 N). The difference among the groups was statistically significant (p = 0.013). The Tukey's HSD post hoc test results for paired groups revealed that the fracture resistance of group IV was significantly higher than group I (p = 0.030) and group II (p = 0.027). Conclusion: The restoration of endodontically treated double-rooted premolars using two fiber posts luted with resin cement, followed by packable composite buildup, showed promising performance regarding fracture resistance.

Purpose: To analyze and compare the positional accuracy of multiple implants using open-tray impression transfer with and without splinting using different splinting materials. Materials and methods: In this study, a heat-cured acrylic model was made with four implant analogs in left and right canine and first molar regions. The model was used to make multiple impressions for sample fabrication. A total of 40 open-tray impressions (10/group) were made. Based on the splinting material used, the groups were named as group A (titanium bar), group B (pattern resin), group C (cold cure acrylic resin), and group D (nonsplinting). Impressions were poured and casts were analyzed for the positional accuracy using coordinate measuring machine. The three-dimensional (3D) coordinates of each implant along the X-, Y-, and Z-axes were measured. One-way analysis of variance (ANOVA) and post hoc Tukey test were done to analyze the significant difference between the four implant analogs of each group with the master model. Results: The implant impressions made using the splinting techniques were more within clinical limits and closer to the reference model rather than nonsplinting technique. Interimplant distance obtained by splinting with cold cure acrylic resin (group C) demonstrated greater variations in X2-, X3-, Y-, and Z-axes. Splinting with pattern resin (group B) was found to be the most accurate method of splinting in the X- and Y-axes, with interimplant distances closer to the reference model. The difference between group B (pattern resin) and group A (titanium bar) was found to be statistically insignificant. Group D (nonsplinting) showed the largest differences when compared with reference model in Z-axis. Conclusion: Implant impressions made by splinting of impression copings provided better positional accuracy compared to those made without splinting. Pattern Resin provides best dimensional accuracy among the various splinting method tested. However, splinting impression copings with titanium bar was statistically similar to that of pattern resin.

Purpose: The fracture resistance and mode of fracture in maxillary incisors restored with the ultraconservative post (size 0) and conventional fiber posts (sizes 1 and 2) subjected to 45° stress. Materials and methods: A total of 60 extracted human permanent maxillary central incisors were decoronated, instrumented, and obturated using the sectional obturation technique. Six groups (n = 10 samples each) were created—group I (size 0 Hi-Rem post), group II (size 1 Hi-Rem post), group III (size 2 Hi-Rem post), group IV (size 0 EasyPost), group V (size 1 EasyPost), and group VI (size 2 EasyPost). Post space was prepared in each root, preparing posts for cementation and core buildup. The specimens were tested for fracture resistance using a universal testing machine at a 45° angle and 1 mm/minute. The mode of failure was visually determined. The paired t-test was done to analyze the difference in fracture resistance within the groups, and the unpaired t-test was used to compare the groups. Results: The mean fracture resistance of EasyPost and Hi-Rem posts with size 0 was higher (618.30 and 624.40 N, respectively) than sizes 1 (544.80 and 561.20 N, respectively) and 2 (464.40 and 479.70 N, respectively). There were statistically significant mean value differences between the two groups for size 1 post (p = 0.008). In all three sizes, Hi-Rem showed a higher mean fracture resistance value than EasyPost. Conclusion: This study found that ultraconservative posts (size 0) of Hi-Rem and EasyPost had greater fracture resistance than conservative posts (sizes 1 and 2). Furthermore, size 0 Hi-Rem posts performed marginally better than size 0 EasyPost. Favorable fractures are most common with both Hi-Rem and EasyPost.

Purpose: To evaluate and compare the antifungal activity of four different essential oils incorporated in tissue conditioner on Candida albicans. Materials and methods: A total of 45 tissue conditioner (Viscogel) samples were fabricated either with different oils or without oils, forming five groups (n = 9/group). A standard amount of 2.2 gm of polymer to 1.8 gm of liquid was used. Liquid monomer without oils (control group) and 20% concentration of four oils [tea tree (Melaleuca alternifolia group), clove (Syzygium aromaticum group), coriander (Coriandrum sativum group), pista (Pistacia vera group)] were homogeneously mixed with the powder to formulate the autopolymerized tissue conditioner samples and stored in distilled water for 7 days. The antifungal properties of the different tissue conditioner samples were assessed by the agar punch well method after 24 hours, and the minimum inhibition zone (MIZ) was measured every day until 7 days. The statistical analysis was done using a one-way analysis of variance (ANOVA), followed by a post hoc test. Results: The tissue conditioner with clove oil (S. aromaticum group) had the highest minimum inhibition diameter (21 mm), followed by pista oil (P. vera group; 20.8 mm), tea tree oil (M. alternifolia group; 20.6 mm), coriander oil (C. sativum group; 20.5 mm), and the control group (20 mm). The difference was statistically significant (p = 0.001). Post hoc analysis showed a significant difference (p = 0.001) between the control group and the four tested groups in minimum inhibition diameter. The intergroup comparison of tested groups showed no significant difference. Conclusion: The antifungal activity of Viscogel with different oils used in the study was superior compared to the control group. The antifungal activity of Viscogel with clove oil (S. aromaticum) against C. albicans was greater compared to other oils used. Within the limitations of this study, the use of these oils along with Viscogel seems beneficial in inhibiting fungal growth.

Purpose: In vitro assessment of the effect of implant site location on the stability and retention of a simulated implant-supported overdenture. Materials and methods: Study was conducted on an edentulous mandibular ridge epoxy resin model. Eight implant analogs with ball attachments were placed in positions mimicking natural dentition (canine, premolar, and molar bilaterally). Four overdenture configurations were evaluated: group I—bilateral canine and first premolar; group II—bilateral canine and second premolar; group III—bilateral canine and first molar; group IV—bilateral first premolar and first molar. Four metal hooks were attached at the location of the attachment on the polished surface of denture bases. Peak dislodging forces were measured using a universal testing machine to evaluate retention and stability. Statistical analysis was conducted using repeated measures analysis of variance (ANOVA), one-way ANOVA, and the Bonferroni post hoc method to determine specific differences between the groups. Results: Significant differences (p < 0.001) were observed when applying forces in different directions and at different implant locations. Group II (bilateral canine and second premolar) exhibited the highest mean values for vertical retention (7.85 N), anterior stability (7.17 N), posterior stability (6.99 N), and right lateral stability (4.85 N). Vertical retention and horizontal stability increased with a distal implant position up to the second premolar in simulated overdenture prostheses. Conclusion: Within the bounds of this investigation, implant distribution and position have a significant impact on the stability and retention of an implant overdenture prosthesis. Specifically, positioning implants more distally, up to the second premolar, can enhance both vertical retention and horizontal stability.