Repair bond strength of dental computer-aided design/computer-aided manufactured ceramics after different surface treatments.

OBJECTIVE: To evaluate the microtensile bond strength of four dental computer-aided design/computer-aided manufactured (CAD/CAM) ceramics after application of four different surface treatments. MATERIALS AND METHODS: Four dental CAD/CAM ceramics were tested: feldspathic ceramic (VITABLOCKS-Mark II), polymer-infiltrated ceramic network (VITA ENAMIC), zirconia-reinforced lithium silicate (VITA SUPRINITY), and yttria-stabilized zirconia (VITA YZ T). Four surface treatments were applied: no treatment, 5% hydrofluoric acid-etching, airborne particle abrasion, and tribochemical silica coating. The ceramic blocks were repaired with nanohybrid composite (Tetric N-Collection). Sixteen test groups of 12 specimens were prepared. After thermocycling, microtensile bond testing was performed. The microtensile strengths values were statistically analyzed using two-way analysis of variance and Tukey's post-hoc test. RESULTS: Repaired feldspathic and resin polymer-infiltrated ceramic network ceramics demonstrated superior microtensile bond strengths compared to zirconia-reinforced lithium silicate and yttria-stabilized zirconia. Etched feldspathic and polymer-infiltrated ceramic network ceramics had higher bond strength than the untreated groups. Surface treatments did not affect the bond strength of zirconia-reinforced lithium silicate and yttria-stabilized zirconia with the exception of etching, which reduced the bond strength of yttria-stabilized zirconia. CONCLUSION: Feldspathic ceramic and polymer-infiltrated ceramic network were repaired with dental composite after surface etching with hydrofluoric acid. Repair of zirconia-reinforced lithium silicate and yttria-stabilized zirconia did not demonstrate promising results. CLINICAL SIGNIFICANCE: Repair of feldspathic ceramic and polymer-infiltrated ceramic network restorations may be a cost-effective means to promote the longevity of dental restorations. However, zirconia and zirconia-reinforced lithium disilicate restorations do not offer such an option.

A Descriptive Analysis of Clinical Articles Published in the Last 50 Years in the Dental Literature.

AIMS: This article describes the methodologies used in the dental literature and described how these approaches have changed over time. MATERIALS AND METHODS: Thirty-three ISI peer-reviewed journals were included in the analyses. Data were extracted independently by 11 investigators and in duplicate. Any differences in the results were resolved via discussion or by a third reviewer when necessary. Data were collected regarding the methodology used in the article, and dental specialty related to different study designs. In the case in which more than one study design or specialty was reported, reviewers were trained to identify the main methodology/specialty. RESULTS: The majority (36.96%) used a case report (CR) as the primary methodology, followed by a clinical trial (CT) (18.21%) or randomized CT (15.11%). The least used methodologies included a cohort (COH) study (6.07%) or a systematic review (SA)/meta-analysis (MA) (6.73%). Periodontology published the highest number of case controls (CCs) (46.8%), randomized CTs (RCTs) (29.9%), cross-sectional (CS) studies (26.0%), SRs/MAs (19.8%), and CTs (17.1%). Oral and maxillofacial surgery published the highest number of CRs/case series (54.5%) and COH studies (30.5%), whereas operative dentistry published the lowest number of CRs/case series (0.7%), CCs (2.9%), and SRs/MAs (2.3%). CRs/case series retain the highest number of publications across all time points in the dental literature overall. CONCLUSION: Our results indicate an improvement in the types of research and the pyramid of evidence, which will help in applying evidence-based dentistry (EBD) in clinical decision-making. CLINICAL SIGNIFICANCE: Types of studies used in the dental field are not yet investigated. Thus, little is known about the common study design types in dental literature. This can affect the decision made regarding technique, risk factors, prevention, or treatment.

Evaluation of microleakage in class-II bulk-fill composite restorations.

BACKGROUND/PURPOSE: Despite the clinical appeal of restoring deep class II cavities in single increment using bulk-fill resin composite, sealing of bulk-filled composite restorations is a concern. This study evaluated interfacial adaptation of bulk-fill composite restoration to axial wall and gingival floor of class II cavities using cross-polarization optical coherence tomography (CP-OCT). MATERIALS AND METHODS: Box-shaped class II cavities were prepared in extracted molars and divided into three groups (n = 7) according to adhesive used; Clearfil SE Bond 2 (SE2), Tetric-N Bond Self-Etch (TSE) or Tetric-N Bond Universal (TNU). All adhesives were applied in self-etch mode and according to manufacturers' recommendation. Then, preparations were bulk-filled with Filtek Bulk Fill Posterior Restorative resin composite and immersed in a contrast agent. Tomographic images of axial wall and gingival floor of each restoration were obtained by CP-OCT (IVS-300, Santec) with a central wavelength of 1330 nm and were imported to an image analysis software to quantify microleakage. RESULTS: Mann-Whitney U test showed statistically significant difference in microleakage percentage between the groups at both axial wall and gingival floor (p < 0.05). SE2 group had the lowest percentage of microleakage (p < 0.05), as only few cross-sections showed areas of reflections from contrast agent penetrating into axial wall (8.23 ±â€¯6.8) and gingival floor (7.07 ±â€¯4.1), followed by TNU group (18.13 ±â€¯12.9 axially and 30.61 ±â€¯11.9 gingivally). Microleakage was frequently observed at the axial wall and gingival floor of TSE group, showing the highest percentages of 25.50 ±â€¯12.5 and 36.97 ±â€¯10.2, respectively (p < 0.05). CONCLUSION: All tested groups exhibited different extent of interfacial microleakage, however, two-step self-etch adhesive yielded superior adaptation in comparison to one-step self-etch adhesive and universal adhesive.

Oral Health Knowledge, Attitudes, and Behaviors Among University Students in Jeddah, Saudi Arabia.

PURPOSE: This study aimed to evaluate oral health knowledge, attitudes, and behaviors among a sample of senior students at King Abdulaziz University (KAU), and to assess differences among these factors between genders. METHODS: A total of 1177 senior university students at KAU were included in this cross-sectional study. Participants were selected by stratified random sampling. KAU has three main streams categorized by field of study. One faculty was randomly selected from each stream. Information regarding oral health knowledge, attitudes, and behaviors was collected with a validated self-administered questionnaire. A knowledge score was calculated, and predictors of oral health knowledge were assessed by linear regression. RESULTS: In general, the mean oral health knowledge score of females (8.1 ± 1.8) was significantly higher than that of males (7.2 ± 2.1) out of 13. Relative to males, females reported a greater frequency of teeth cleaning and of using a toothbrush with proper technique (p < 0.001). Females were also more likely to have ever visited a dentist than males (95% and 86%, respectively). The linear regression model revealed that students in non-medical faculties and those who were not shown how to brush their teeth by a dentist had lower oral health knowledge scores, than their counterparts. Students older than 22 years and females were more likely to have higher oral health knowledge scores than were their counterparts. CONCLUSION: Oral health knowledge was relatively low among the university students, but females showed better oral health knowledge and behaviors than males did.