Aim and objective:To evaluate the effect of 50 % (v/v) dimethyl sulfoxide (DMSO) pretreatment on immediate (24 h) and delayed (6 months) microtensile bond strength (μTBS) of an etch-and-rinse adhesive and two universal adhesives to dentin. Materials and methods:A total of 144 extracted human molars were decoronated, pulp chambers exposed, and roots sectioned 2 mm apical to the CEJ. Teeth were randomly divided into six experimental groups (n = 24), based on surface pretreatment and adhesive system used: Group 1A: Adper Single Bond 2 (ASB) Group 2A: Tetric N-Bond Universal (TNBU) Group 3A: Prime & Bond Universal (PNBU) Groups 1B, 2B, and 3B received the same adhesives, respectively, following a 50 % (v/v) DMSO wet bonding pretreatment. All adhesives were applied per manufacturer's instructions, followed by composite resin build-up. Ten samples per group were tested for μTBS at 24 h and ten after 6 months of storage. Failure mode was analyzed. Four additional samples per group underwent SEM evaluation to observe the resin-dentin interface. Statistical analysis:Data were analyzed using one-way ANOVA and Tukey's post hoc test for intergroup comparisons. Unpaired t-tests were applied for two-group comparisons. Significance was set at p < 0.05. Results:DMSO pretreatment significantly improved both immediate and long-term μTBS (p < 0.05) across all adhesives. PNBU exhibited the highest bond strength at both time intervals. Conclusion:Dentin pretreatment with 50 % DMSO prior to adhesive application enhances immediate μTBS and preserves bond durability at 6 months, regardless of adhesive system used.
Background Porphyromonas gingivalis (P. gingivalis) is a key pathogen in chronic periodontitis that drives dysbiosis and tissue destruction. Anaerobic culture often underestimates fastidious bacteria, whereas real-time polymerase chain reaction (RT-PCR) can provide higher sensitivity and accurate quantification. This study compared both methods for detecting and quantifying P. gingivalis in subgingival plaque from patients with chronic periodontitis and healthy controls. Methodology In total, 32 participants (16 with chronic periodontitis and 16 healthy) were included. Pooled subgingival plaque samples were analyzed by anaerobic culture on selective media and by RT-PCR targeting the 16S rRNA gene with a TaqMan probe and standard curve quantification. Clinical parameters were recorded (probing depth (PD), clinical attachment loss (CAL), and gingival index (GI)), and data were analyzed using t-tests, chi-square tests, Pearson's correlation, and diagnostic metrics. Results Participants with chronic periodontitis had significantly higher clinical parameters (PD = 6.38 ± 0.96 mm, CAL = 3.63 ± 1.09 mm, GI = 2.50 ± 0.22; all p = 0.001) and P. gingivalis loads (culture = 82.13 ± 54.26 CFU/mL, p = 0.031; RT-PCR = 97.44 ± 59.02 CFU equivalents/mL, p = 0.039) than controls. Bacterial load showed moderate positive correlations with clinical parameters (r = 0.35-0.42, p < 0.05). RT-PCR detected P. gingivalis in 59.4% of samples versus 50% by culture, achieving 100% sensitivity and 90.6% accuracy. Conclusions RT-PCR is more sensitive than culture for P. gingivalis detection, supporting its use for improved periodontal diagnosis and risk assessment.
BACKGROUND:Accurate shade selection is critical for achieving esthetic success in fixed prosthodontics. This in vitro study aimed to compare the accuracy and reliability of shade selection using conventional visual assessments, digital camera photography, and smartphone photography. MATERIALS AND METHODS:Ten shade tabs were evaluated by 10 observers (three professors, four postgraduate students, and three laboratory technicians), resulting in 100 observations per method. Shade matching was performed using the VITAPAN Classical shade guide (VITA Zahnfabrik H. Rauter GmbH and Co. KG, Bad Säckingen, Germany) under standardized daylight conditions (5000-6500 K). Visual selection relied on direct comparison, while digital camera and smartphone images were captured with consistent settings. Accuracy was determined based on agreement with a predetermined reference shade. Statistical analyses included Cochran's Q test for overall differences, pairwise McNemar tests with Bonferroni adjustment, Fleiss' kappa for inter-observer agreement, and Cohen's kappa for intra-observer agreement between methods. RESULTS:Both digital camera and smartphone methods demonstrated significantly higher accuracy and consistency than the visual approach. Digital camera and smartphone photography showed substantial inter-observer reliability and strong agreement between the two digital techniques, effectively reducing the variability associated with observer experience. No meaningful differences were observed between the digital camera and smartphone methods. CONCLUSION:Digital cameras and smartphone photography provided reliable, objective alternatives to conventional visual shade selection, offering improved accuracy and reproducibility. These techniques hold promise for enhancing shade communication in clinical prosthodontics, particularly in settings where accessibility and standardization are priorities. Further in vivo investigations are warranted to confirm its applicability in clinical conditions.
Background: The primary objective of periodontal therapy is to restore the compromised periodontium through regenerative processes. Platelet-rich fibrin (PRF) is a vital biomaterial in this context due to its rich concentration of growth factors within a fibrin matrix. Aim: This study aimed to compare the efficacy of leukocyte-PRF block (L-PRF block) and advanced PRF (A-PRF) combined with bone graft (hydroxyapatite) in treating infrabony defects (IBDs). Materials and Methods: Forty sites with IBDs were randomly assigned to two groups: Group A received A-PRF with bone graft, and Group B received L-PRF block. Criteria for inclusion included probing pocket depth (PPD) ≥5 mm, clinical attachment loss (CAL) ≥3 mm, gingival index (GI) ≥1, and evidence of IBDs ≥ 3 mm observed via cone beam computed tomography. Measurements of GI, PPD, CAL, crestal level (CL), and bone fill were recorded at baseline, 3 months, and 6 months. Results: Both groups showed significant reductions in GI at the 6-month mark ( P < 0.05). In Group A, PPD decreased from 6.850 ± 1.2258 (baseline) to 3.750 ± 0.9105 (6 months), and CAL decreased from 11.100 ± 1.8035 to 8.000 ± 2.2243. In Group B, PPD reduced from 7.500 ± 0.8885 to 3.250 ± 0.5501, and CAL reduced from 11.250 ± 1.5517 to 7.000 ± 1.7472 at 6 months. Intergroup comparisons showed a better outcome for PPD in Group A, while CAL differences were statistically non-significant. IBD measurements and bone fill comparisons between the groups were also non-significant. Conclusion: In conclusion, both L-PRF block and A-PRF combined with bone graft showed significant improvements in assessed parameters over six months. However, there were no significant differences between the two groups, indicating both treatments are effective for addressing IBDs.
Introduction Endodontically treated posterior teeth are weakened by the loss of coronal structure and require durable restoration to prevent fracture. Conventional post-core-crown systems often involve additional dentin removal, which increases the risk of root fracture. Endocrowns may offer a conservative alternative that uses the pulp chamber for retention. This in vitro study aimed to compare the fracture resistance and failure modes of endodontically treated mandibular first molars restored with lithium disilicate endocrowns versus fiber post-core and lithium disilicate full crowns. Materials and methods Sixty extracted mandibular first molars were root canal treated, randomly divided into two groups (n = 30 each), and restored: Group 1 with computer-aided design and computer-aided manufacturing lithium disilicate endocrowns and Group 2 with fiber posts, composite cores, and lithium disilicate crowns. All specimens were cemented with dual-cure resin cement, stored in water for 24 hours, embedded in acrylic, and tested under compressive load (1 mm/min) using a universal testing machine. The fracture load (N) and failure mode (favorable versus unfavorable) were recorded. Data were analyzed using the Shapiro-Wilk test, independent samples t-test, and descriptive statistics (α = 0.05). Results The mean fracture resistance of teeth restored with lithium disilicate endocrowns was 1250.45 ± 152.30 N, whereas the post-core-crown group demonstrated a mean value of 1180.20 ± 178.60 N. Although the endocrown group exhibited slightly higher fracture resistance, the difference between the groups was not statistically significant (p = 0.106). Failure mode analysis revealed a marked difference in the pattern of fractures between the groups. Endocrowns showed a significantly higher proportion of favorable (restorable) failures, primarily involving debonding or fractures above the cemento-enamel junction. In contrast, the post-core-crown group exhibited a higher incidence of unfavorable (non-restorable) fractures, including vertical root fractures and post-related failures. Conclusions Within the limitations of this in vitro study, lithium disilicate endocrowns demonstrated fracture resistance comparable to conventional fiber post-core restorations followed by full crowns. Importantly, endocrowns were associated with a significantly higher proportion of favorable, restorable failure patterns, suggesting a biomechanical advantage. The absence of intraradicular post placement likely contributes to improved stress distribution and reduced risk of catastrophic root fractures. Clinically, these findings support the use of endocrowns as a conservative and reliable restorative option for endodontically treated posterior teeth with adequate coronal structure. Their use may enhance long-term prognosis while preserving tooth structure and simplifying the restorative procedure.
