Dentistry Journal最新文献

Background: To investigate the effect of zirconium dioxide nanoparticles (ZrO₂NPs) on the shear bond strength (SBS) of hard denture lines bonded to different denture base resins.

Methods: Five different denture bases were used in this study: conventional heat-cured resin, IvoCad, AvaDent, NextDent, and FormLabs, in acrylic specimens of 10 × 10 × 2.5 mm³ (N = 150, n = 10). Specimens were centered at the bottom of a silicon mold to create an auto-polymerized holder. Three major groups of reline material were used: no ZrO₂NPs (control), 2 wt.%, and 4 wt.% ZrO₂NPs. Reline was bonded to the resin surface using a customized jig. After polymerization, specimens were stored in distilled water, and 5000 thermal cycles were performed. Each specimen was fixed to an Instron machine, and SBS was tested using a blade loaded (1 mm/min) at the resin interface until failure. Data was collected and analyzed using two-way ANOVA and post hoc Tukey test (α = 0.05).

Results: AvaDent showed the highest SBS when compared with other denture base materials (p < 0.001) except for IvoCad. The addition of ZrO₂NPs significantly decreased the SBS of AvaDent (p = 0.003) and IvoCad (p = 0.001), while heat polymerized resin, Formlabs, and NextDent showed no significant change in SBS (p > 0.05).

Conclusion: CAD-CAM milled denture base resin showed higher SBS with pure denture reline. The addition of ZrO₂NPs decreased the SBS of reline with CAD-CAM milled denture base resins but did not change bond strength with 3D printed and conventional denture base resins.

The aim of this study was to find in the literature data on the relationship between implant surface roughness and implant stability achieved, from the time of placement to three months afterward, to help us to know what type of surface roughness is more favorable to guarantee implant stability and osseointegration. A systematic review was conducted in accordance with the PRISMA 2020 (Preferred Reporting Items for Systematic Review and Meta-analysis) statement, and the protocol was registered on the Open Science Framework. The specific inclusion and exclusion criteria were selected using the PICOS framework. The databases Medline (PubMed), Scopus, the Web of Science and The Cochrane Library were searched up to October 2023. The selection of studies and data extraction were conducted by two independent reviewers. The review included a total of 11 studies. A total of 1331 dental implant placements were identified. Two of the eleven selected studies were on humans in vivo, eight were on animals in vivo, and one was on animals in vitro. A statistically significant correlation between surface roughness and implant stability as measured by resonance frequency analysis (RFA) was not identified in ten of the eleven selected studies. It appears that there is no correlation between primary stability and the degree of implant roughness. However, there appears to be a correlation between the roughness of the implant and the degree of osseointegration, as indicated by bone-implant contact values. This correlation is more closely related to secondary stability. The great methodological variability makes it difficult to compare data and draw conclusions, so it would be desirable to agree on a common methodology to help draw appropriate conclusions from published studies.

Osteoporosis is a common systemic bone disorder in the elderly, characterized by low bone mineral density and deterioration of bone structure. Apical periodontitis is an inflammatory response to the microbial infection of root canals, typically characterized by apical bone destruction surrounding the tooth's apex. This systematic review aimed to determine if osteoporosis affects the prevalence of apical periodontitis in adults. PRISMA guidelines have been followed. It included randomized clinical trials, cross-sectional, cohort, and case-control studies, and excluded non-relevant investigations and various secondary sources. A comprehensive search was performed in PubMed, Scopus, and Web of Science, until 13 March 2024. The Newcastle-Ottawa Scale was used to assess the quality of the three selected studies: two cross-sectional studies and one case-control study. One investigation only included post-menopausal women recruited at a dental university clinic, the other integrated data from the total hospital patients' population, and the third selected patients referred to the university dental clinic from the university hospital. The findings varied: one study noted a marginal association between low bone mineral density and apical periodontitis, another found a significant association, and the third, with the lowest risk of bias, reported no link. The main limitations were the scarcity of eligible studies and their overall quality. The review was registered in the PROSPERO database (CRD42024523705), applied strict inclusion criteria and thorough searches by experienced and independent reviewers. There is no strong evidence that adult individuals with osteoporosis have a higher probability of developing apical periodontitis. However, clinicians should remain cautious of osteoporosis's potential impact on apical periodontitis development.

We carried out a comparison of the neuromuscular and clinical effects produced by electrostimulation therapies, as an adjuvant to the use of occlusal splints (removable muscle relaxation apparatus) in patients with temporomandibular disorders In this simple randomized clinical trial, 91 patients were randomly divided into three groups. Group A (GA) received transcutaneous electrostimulation therapy and an occlusal splint, Group B (GB) received percutaneous electrostimulation therapy and an occlusal splint, and Group C (GC) received an occlusal splint. The neuromuscular activity, as well as the signs and symptoms of each patient, were evaluated every week throughout the treatment (T0 = baseline; T1 = 7 days; T2 = 14 days; T3 = 21 days; T4 = 28 days; and T5 = 35 days). Pain was measured with a visual analog scale, and neuromuscular electrical activity was determined by the root mean square of the masseter muscles through the use of a UNAM-CINVESTAV 1.2 electromyograph. Comparisons were made using ANOVA for repeated measures (p-value = 0.05). The comparison between the groups determined that muscle fatigue (p-value = 0.001), joint pain (p-value = 0.009), and muscle pain (p-value = 0.003) decreased to a greater extent, and in the short term for the group treated with transcutaneous electrostimulation therapy as an adjuvant to the use of the occlusal splint. The comparison between the groups determined that muscle fatigue (p-value = 0.001), joint pain (p-value = 0.009), and muscle pain (p-value = 0.003) decreased to a greater extent and in a shorter term in the GA (calculation therapy, transcutaneous electrostimulation) and GB (occlusal splint). Transcutaneous electrostimulation is a feasible and faster alternative that was accepted by most of the patients for treating temporomandibular disorders.

Background: The purpose of this study was to assess the awareness of molar incisor hypomineralisation (MIH) and hypomineralised second primary molars (HSPMs) among dental practitioners in Northern Italy, and to gather data on the occurrence of these conditions in their paediatric patients.

Methods: A cross-sectional study was conducted using a structured online questionnaire administered through Google Forms. The survey comprised 10 single-choice questions addressing the occurrence of MIH and HSPM in caries-free patients aged 6-9 years.

Results: A total of 315 dentists participated in the survey, yielding a response rate of 31.5%. The majority of respondents reported that 1-25% of their paediatric patients exhibited HSPMs. Among this group, 43.62% of respondents observed MIH in 1-25% of cases.

Conclusion: The findings from this survey suggest a consistent perception of MIH and HSPMs among dental practitioners, aligning with known prevalence data and indicating recognition of these conditions within the dental community in Northern Italy.

The study of tooth morphology is a critical component of the dental curriculum, highlighting the importance for dental students to acquire comprehensive and detailed knowledge of the complex structure of teeth. This study compared the educational outcomes of two student cohorts in a tooth morphology course, using traditional methods for the control group and additional digital video-based resources for the experimental group. We hypothesized that early integration of digital resources would significantly reduce the learning time. We retrospectively analyzed two groups of Master of Dentistry students. The control group (42 students) was taught using the traditional 'tooth puzzle' method, while the experimental group (42 students) supplemented traditional teaching with digital video-based tools developed by our department. Both groups' curricula culminated in a practical post-course test requiring the identification of 40 teeth, along with a mid-course test to track the students' learning progression. The number and type of incorrectly identified teeth were recorded. The mid-course test showed significant performance differences. The control group had a median (Q1, Q3) value of faults of 12.0 (7.8, 20.5), whereas the respective value for the experimental group was 4.0 (0.0, 8.0) (p < 0.001). In the control group, none achieved faultless results, with only two students (4.8%) having at most two faults, and six students (14.3%) having no more than four faults. The control group averaged 13.5 faults per student, with 19 students (45.2%) failing the test. Conversely, the experimental group showed improved performance: 12 students (28.6%) had no faults, and 25 students (59.5%) had four or fewer faults. The experimental group averaged 5.2 faults per student, with only four students (9.5%) failing. By the end of the course, both groups achieved commendable results on the practical tooth identification test. The experimental group slightly outperformed the control group, though the difference was not significant. The median (Q1, Q3) values were 0.0 (0.0, 2.5) and 1.0 (0.0, 4.5) for the experimental and control groups, respectively (p = 0.372). The students using both traditional and structured digital video-based tools showed greater learning advancement than those using only the traditional 'tooth puzzle' method.

Background: The purpose of this study was to compare the microgap size between engaging (E) and non-engaging (NE) abutments and screw morphology changes between E and NE abutments using scanning electron microscopy (SEM) before and after cyclic loading (CL).

Methods: Thirty-six implants were arranged into four groups as follows: Group 1, single units with E abutments; Group 2, single units with NE abutments; Group 3, three-unit fixed partial dentures with a hemi-engaging design; and Group 4, three-unit FPDs with two NE abutments. The microgap was evaluated using a stereomicroscope. SEM was used to qualitatively evaluate screw morphology. The specimens were subjected to axial loading first and then lateral loading (30°) using the settings; one million cycles (1.0 × 10⁶ cycles) for each loading axis.

Results: There were no significant differences detected in the microgap sizes between the E and NE abutment groups. In addition, there were no significant changes in the microgap sizes after CL in the E or NE abutment specimens. More damage to the screws was noticed after CL compared to before, with no difference in the patterns of damage detected between the E and NE abutments.

Conclusions: No significant difference in microgap size was detected between the E and NE abutments. Furthermore, there was no significant difference in microgap size between the different prosthetic designs. From the SEM qualitative evaluation, there were similar screw morphology changes after CL between the E and NE abutments.

The critically important preoperative and intraoperative factors that affect the success of endodontic microsurgery (EMS) in Japanese patients are not defined. We conducted a retrospective study that analyzed treatment outcomes for 46 teeth in 46 Japanese patients. Treatment was provided between March 2013 and March 2015. All patients were evaluated after one year, the shortest time period over which treatment outcomes after apicoectomy could be evaluated and in which there were complete records for the recruited patient population. Healing was assessed on the basis of clinical symptoms and radiographs. With the use of a binary logistic regression model to quantify success, we estimated the effects of patient age, sex, dental arch, lesion size, lesion type, preoperative root canal treatment, the presence or absence of a post core, and the presence or absence of an isthmus on the surgically prepared dentine surface. The overall success for EMS was 93.5% after one year; failures comprised 6.5%. Successful outcomes were higher (p = 0.04) for maxillary teeth than for mandibular teeth. Success was higher (p = 0.019) for patients who received root canal instrumentation prior to EMS. Age, sex, lesion size, lesion type, the presence or absence of a post core, and the presence or absence of a root canal isthmus had no effect (p > 0.2) on success. We conclude that the percentage of successful outcomes after EMS treatment for Japanese patients presenting with periapical periodontitis is very high after one year and that success is influenced strongly by the dental arch and preoperative root canal instrumentation.

Controlling root movement is one of the greatest challenges in orthodontic treatment with aligners, like Invisalign^® aligners. Cone Beam Computed Tomography (CBCT) integration into ClinCheck^®, enabling bone and root visualisation, allows a more accurate follow-up of the teeth position. This study aims to compare torque measurements of the upper central incisors with and without CBCT and relate them to the upper incisor inclination and facial biotype. In a sample of 70 teeth, torque measurements were obtained by importing images into AutoCAD^® software (version 2024). The angle between the tooth's long axis with CBCT duplicate and the tooth's long axis without CBCT was obtained to assess the difference. Statistically significant differences between torque measurements with and without CBCT were found, as well as between these measurements and the inclination of the upper incisors. No statistically significant differences were found among the facial biotypes. The average values of 27.8° ± 3.4° and 21.5° ± 3.2° were obtained for the angle between the axes. Torque without CBCT was lower than torque with CBCT, for the same tooth. The angle between the axes had a similar mean for both teeth. CBCT integration into ClinCheck^® allows for a more correct torque measurement.

Background: Reading nutritional labelling helps consumers select healthier food, thereby benefitting their oral health. The purpose of this study was to describe the knowledge, attitudes, and practices (KAPs) of parents and carers of children and preteens, associated with reading nutritional labelling, selecting sweetened ultra-processed foods, and their impact on oral health.

Materials and methods: This was a descriptive cross-sectional study in which a validated questionnaire was administered to 298 parents and caregivers of children aged 1-12 years from different districts in Villavicencio, Colombia. Participants' scores, based on the number of correct answers, were used to classify their level of KAP as low, medium, or high. In addition, the frequency of responses, the KAP levels, and the median scores were analysed. Finally, associations were determined using the chi-square test.

Results: Most participants reached a medium level in terms of knowledge (41.6%) and attitudes (49.3%) and a low level in terms of practices (43.3%). An association was found between participants' level of KAPs and their socioeconomic and educational level (p < 0.05).

Conclusions: The study findings reveal inadequate KAPs associated with nutritional labelling, adequate food selection, and the importance of oral health.