Journal of Dental Research, Dental Clinics, Dental Prospects最新文献

Background: This study examined the effect of ethylenediaminetetraacetic acid (EDTA) and etidronic acid (HEDP) in retrograde cavities on the bond strength of MTA Angelus and NeoPutty.

Methods: Sixty-six teeth with single roots and canals were decoronated and enlarged up to F3 using the ProTaper Universal file system. After removing the apical 3 mm within the scope of endodontic surgery procedures, retrograde cavities were prepared with ultrasonic tips. The teeth were divided into three main groups according to the irrigation solution used: saline, 17% EDTA, and 9% HEDP. Following the irrigation of retrograde cavities, each main group was further divided into two subgroups in terms of using MTA Angelus and NeoPutty as retrograde filling materials. Bond strength values of hydraulic cements were measured by the push-out test. Fracture modes were examined under a stereo microscope. Two dentin sections from each group were examined under scanning electron microscopy (SEM) to observe dentinal tubules. Two-way ANOVA and post hoc Tukey tests were used to analyze the data.

Results: Irrigation solutions similarly affected the bond strength values of hydraulic cements (P=0.115). MTA Angelus showed significantly higher values than NeoPutty in all the solution groups (P=0.34). Adhesive and cohesive fracture modes were mostly observed in the MTA Angelus and NeoPutty groups, respectively.

Conclusion: EDTA, HEDP, and saline had a similar effect on the bond strength of hydraulic cements. The higher bond values of MTA Angelus compared to NeoPutty could support its safe use in endodontic surgery procedures.

Background: This study explored the layperson's perception of comfort, satisfaction, and willingness to use various accessories in clear aligner therapy.

Methods: A total of 267 people analyzed standardized intraoral photographs of a female model in orthodontic treatment using: 1) only clear aligner (CA), the control group; 2) clear aligner+attachments (AT); 3) clear aligners+Cl II elastics (EL); 4) clear aligner+hybrid treatment with esthetic braces (HEB); 5) Clear aligner+hybrid treatment with metallic braces (HMB); 6) clear aligner+mini-implants (MI); 7) clear aligner+mini-implants and elastics for intrusion (MIE). In addition, a social media questionnaire was distributed to assess the willingness to undergo orthodontic treatment with various accessories.

Results: There was a significant difference between CA and all the other groups (P<0.001), with CA being considered more comfortable and providing greater satisfaction compared to other accessories. Moreover, AT showed a significant difference in reducing treatment time compared to other groups.

Conclusion: The CA was the most comfortable, exhibiting a higher satisfaction rate and a greater willingness to use it. The AT therapy was perceived as more comfortable and was associated with higher satisfaction and a greater likelihood of use, especially if it resulted in reduced treatment time. On the other hand, the participants reported that the HMB, MI, and MIE accessories were less comfortable.

Background: This study aimed to systematically and comprehensively review the effect of various treatment variables on apically extruded debris (AED) during non-surgical root canal retreatment (NSRCRT).

Methods: The study protocol is shared in the Open Science Framework database (https://osf.io/kjtdg/?view_only=17060180705745ec9dae9a01614f3880). An electronic search was conducted up to July 2022 to reveal related studies. Two reviewers critically assessed the studies for eligibility against inclusion and exclusion criteria and data extraction. Quantitative data synthesis was performed, and the risk of bias in the studies was also evaluated.

Results: Forty-six studies were included in the systematic review and 14 in the meta-analysis. Conflicting or limited evidence was found for the effect of sealer type, obturation technique, and solvent use. The manual instrumentation increased the amount of AED compared to rotary instrumentation during the removal of filling materials (P<0.001). There was no significant difference in the amount of AED between the use of rotary and reciprocating files during the removal of filling materials (P=0.181).

Conclusion: Rotary instruments can be recommended instead of manual instruments during the removal of filling materials to control the amount of AED. Further studies with a low risk of bias are needed to clarify the effect of other treatment variables on AED during NSRCRT.

Background: Managing benign oral soft tissue lesions presents a clinical challenge, often requiring invasive procedures with associated drawbacks. The Er,Cr:YSGG laser has emerged as a potential solution, given its precision and minimal tissue disruption in other medical contexts.

Methods: This pre-post study involved 16 participants diagnosed with benign oral soft tissue lesions. The lesions were excised using the Er,Cr:YSGG laser (2780 nm) with 2.75‒3.75-W power outputs. Pain was quantified using a numerical rating scale from 0 to 10, and edema presence was noted. Function interference and satisfaction were graded. Healing was assessed via the Early Wound Healing Score (EHS). The observation spanned three postoperative intervals: day 1, day 3, and day 7.

Results: This study included 16 participants with benign oral soft tissue lesions, predominantly pyogenic granuloma and fibroepithelial polyp. Initial discomfort and bleeding were common, while a small proportion reported pain. Er,Cr:YSGG laser treatment significantly reduced discomfort (VAS score) and promoted healing (EHS score) over time. Function interference decreased, and patient satisfaction improved from day 1 to day 7. Additionally, bleeding scores decreased drastically, confirming the laser's effective hemostatic properties.

Conclusion: The findings suggest that Er,Cr:YSGG laser treatment presents a promising, less invasive approach for managing oral benign soft tissue lesions, prioritizing patient well-being and contentment alongside successful lesion removal.

Background: Understanding the characteristics of the pterygoid hamulus (PH) is crucial for diagnosing and treating various oropharyngeal and craniofacial conditions. It also aids in interpreting radiographs and diagnosing unexplained oropharyngeal pains. Cone-beam computed tomography (CBCT) is a valuable tool, offering clinical insights into this previously understudied area. Accordingly, this study aimed to evaluate the morphology and dimensions of the PH and its changes by ageing in 20-40-year-old women in the Dental Branch of Islamic Azad University of Sciences, Tehran, Iran.

Methods: This cross-sectional study was conducted on CBCT scans from 258 women aged 20-40. The morphology, length, width, and angle of the PH in coronal and sagittal planes were investigated.

Results: The average length of the right and left hamulus was 5.50±1.37 and 5.37±1.36 mm. The average width of the right and left hamulus was 2.16±0.72 and 2.11±1.06 mm. The average coronal angle of the right and left hamulus was 22.3±9.79° and 30.16±8.99°. The average sagittal angle of the right and left hamulus was 26.11±7.26° and 26.34±7.63°. In contrast with the sagittal angle, the right and left hamulus's length, width, and coronal angles were not symmetrical. Slender morphology was the most frequent morphology, and it was symmetrical only in the 20-30-year-old age group. Finally, no variable was affected by ageing.

Conclusion: Hamulus dimensions and morphology did not change with ageing in women aged 20-40. The PH symmetry varied by age group. Also, CBCT was a suitable tool for investigating hamulus changes.

Background: In implant-supported overdentures increase in the number of implants improves the retention and stability of the overdentures. A direct correlation exists between prosthesis retention and patient satisfaction. Therefore, this experimental study assessed the effect of attachment type and implant position on the retention of mandibular implant-supported overdentures.

Methods: A transparent acrylic resin model of the mandible was fabricated, and dental implants were positioned at the first molar area (position 6), between the lateral incisor and canine teeth (positions B and D), and first premolars (positions A and E) bilaterally. Novaloc attachments (strong, medium, and light retentive caps) were used with ABDE, 6AE6, and 6BD6 implant positions. A Dolder bar attachment was also used with the ABDE implant position. Overdenture retention was measured under vertical loading, and the maximum dislodging force (MDF) was recorded. Data were analyzed by two-way and one-way ANOVA and post hoc Tukey tests (α=0.05).

Results: The effects of attachment type and implant position [except for ABDE and 6AE6 with light retention insert (P=0.49), and 6AE6 and 6BD6 with strong retention insert (P=0.48)], and their interaction effect were significant on MDF (P<0.01). The highest retention was recorded for bar attachment (65.15 N), with the lowest for Novaloc attachment with light retention insert at ABDE implant position (11.97 N).

Conclusion: With Novaloc attachments, minimum retention was recorded in ABDE, and maximum retention was recorded in the 6BD6 implant position due to the increased distance between attachments. The strong insert showed the highest retention value, which confirmed the manufacturer's claim. Maximum retention was recorded with the bar and clip attachment.

Background: Severe caries in early childhood is a concern for both children receiving dental treatment and their parents. This dental disease progresses rapidly and quickly damages the coronal part of the tooth. When there is insufficient coronal structure to support a coronal restoration, using intracanal components following root canal treatment increases tooth resistance and helps provide retention for the coronal restoration. This study compared the shear bond strength of three types of intracanal posts (composite resin post, reverse metal post, and fiber post) in severely damaged primary anterior teeth.

Methods: This in vitro study was conducted on 30 extracted anterior primary teeth with at least two-thirds of healthy roots and no prior pulp treatment. The teeth were randomly divided into three groups of 10: group 1: composite resin post with 8th generation universal bonding, group 2: reverse metal post with GC restorative glass cement, and group 3: fiber post with GC restorative glass cement. After placing the post, the samples were restored with a height of 3 mm from cementoenamel junction (CEJ) using an Anterior GC Gradia Packable composite resin. All the samples underwent 500 cycles of thermocycling in a hot water bath at 55±2 °C and a cold water bath at 5±2 °C. The shear strength of the samples was then evaluated using an electromechanical universal testing machine at a rate of 1 mm/min and at a location 2 mm coronal to the CEJ in terms of megapascals.

Results: The average shear bond strength of composite resin posts with 8th generation bonding application was 8.02220 MPa, reverse metal posts with glass ionomer application was 13.8600 MPa, and fiber posts with glass ionomer application was 9.7400 MPa.

Conclusion: Based on these findings, it can be concluded that the highest shear bond strength in this study was related to the reverse metal post, and the lowest shear bond strength was related to the composite resin post. According to the results, reverse metal posts demonstrated better shear bond strength than composite resin posts and fiber posts (P<0.05).

Background: This in-vivo study evaluated the accuracy of full-arch digital impressions obtained through different intraoral scanning technologies regarding trueness and efficiency against the standard alginate impressions.

Methods: Alginate impressions were taken from 50 subjects, and the resulting stone casts were scanned using the Trios 3Shape desktop scanner. In-vivo scans were conducted on each participant using three intraoral scanners: Medit, CEREC Primescan, and 3Shape Trios. The scanned files were superimposed onto two software platforms: the 3Shape Orthoanalyser and Geomagic software. This superimposition was performed against the reference model to calculate 3D and 2D deviations, enabling efficiency comparisons between digital and traditional workflows based on work time in minutes. Measurements and comparisons were made in three planes: transverse, sagittal, and vertical dimensions for all the models and stone casts. Statistical analysis employed SPSS 23, with the significance level set at P<0.05.

Results: Significant deviations were observed between the three intraoral scanners and the alginate impression, with molar and premolar areas showing greater imprecision across dental arches. Compared to the alginate technique, Medit i500 tended to reduce the transverse dimension in the areas mentioned above, while CEREC exhibited higher precision. Molar and premolar areas emerged as the regions with the greatest discrepancies, both in excess and deficiency, compared to the alginate impression. This difference in dimensions was, however, statistically insignificant overall. 3Shape Trios exhibited the shortest scan times, indicating higher efficiency. Among the intraoral scanners, Medit recorded the longest scanning duration.

Conclusion: Accepting the null hypothesis, the scans obtained using all three scanners were comparable with statistically insignificant differences in the measurements. The three scanners differed in the total scan time taken, with the Medit scanner requiring the longest scan time and the 3Shape TRIOS 3 scanner demonstrating the shortest scan duration.

Background: The objectives were to assess the impact of dental caries on the daily living of the geriatric population and determine the factors that influence the relationship between dental health and the daily living of the geriatric population.

Methods: A descriptive cross-sectional study was carried out over six months at Rawalpindi's public and private dental hospitals. Participants aged≥60 years, both male and female, were selected. The calculated sample size was 281. Desired sample from one of the dental hospitals was collected using a non-probability consecutive sampling strategy. Data about sociodemographic characteristics and the DMFT index were collected. Adapted validated tool dental impact on daily living (DIDL) was used to assess the impact of dental health on daily living.

Results: Chi-squared test of association showed a positive association between the DIDL and sociodemographic variables, including age (P=0.001), gender (P=0.001), education (P=0.001), income (P=0.001), occupation (P=0.029), marital status (P=0.001), living arrangement (P=0.001), and history of chronic illnesses (P=0.001). The association between the DMFT index and DIDL also showed statistically significant results (P=0.001). Binary logistic regression analysis indicated that gender (OR=6.98, P=0.005) and the individual's dental health (OR=6.43, P=0.001) were the strongest predictors of the impact experienced in daily life activities. The overall model was statistically significant (χ²=51.24, P=0.001), and the variables were responsible for 32.4% of the variance in the outcome variable.

Conclusion: The study provides strong evidence that sociodemographic factors, DMFT index, gender, and individual dental health significantly contribute to the impact of dental health on daily living. Gender and individual dental health emerge as particularly influential predictors. These findings emphasize the need for targeted interventions and awareness programs, especially for groups with a higher risk of experiencing a significant impact on daily life due to dental issues.

Background: The widespread use of dental implants as a predictable treatment choice has drawn attention to their complications as a major challenge despite their high clinical success rates. In this context, loosening of the abutment screw in posterior single crowns is the most common problem; the use of adequate preload and proper anti-rotational features at implant‒abutment interface appear to be two main solutions to such a problem. The present study evaluated the effect of implant‒abutment connections in four different implant systems before and after cyclic loading.

Methods: Intra-Lock, Dentis, Xive, and Dio implant systems were used in this study. Each system underwent one million cycles of dynamic forces eight times with a magnitude of 110 N. For each specimen after tightening the screw with a torque of 32 Ncm, the detorque values were measured and recorded by a digital torquemeter after and before cyclic loading. Data were analyzed by Kolmogorov-Smirnov, Levene's, one-way ANOVA, and post hoc Tukey tests.

Results: Initial detorque values between the study groups showed significant differences (P<0.0001). Pairwise comparisons showed significantly lower primary detorque values in the Dentis system compared to the three other systems (P<0.0001). After cyclic loading, significant differences were observed between the study groups (P<0.0001). Pairwise comparisons of the groups showed significant differences between all the systems after loading.

Conclusion: The type of implant‒abutment connection is an essential factor influencing the amount of abutment screw loosening.