International Journal of Dentistry最新文献

Background: Thermographic-infrared changes during osteotomy surgery depend on the type of motor used, size, and system of the dental implant. This study undertakes the evaluation of these thermal variations for successful optimization of dependent surgical procedures while aiming toward reduced thermal damage to the bone tissue.

Methods: An in vitro comparative study was conducted to assess the thermographic-infrared changes during surgical osteotomy influenced by the motor type, diameter, and dental implant system. The Checklist for Reporting in vitro Studies (CRIS) guidelines were adopted to report the findings. Bones with fractures, structural damage, or anomalies were omitted. The bones were stored at -20°C, then thawed, cleaned, disinfected, and calibrated. The implant motors (Coxo, W&H, Dentflex, and Baby Driller) were calibrated for equal performance. Standardized drilling procedures were followed using initial, pilot, second, and final drills. A Fluke TiS55+ thermographic camera recorded temperature changes every 10 s, being maintained at 30 cm.

Results: ANOVA analysis revealed significant differences in temperature variations between the implant systems and drill types (p = 0.001). The Coxo and Dentflex motors showed higher mean temperatures (26.57 and 27.65°C, respectively) compared to the W&H and Baby Driller (24.45 and 24.65°C, respectively). Regression analysis indicated that baseline (β = -0.67, p  < 0.01), pilot drill (β = 0.37, p  < 0.01), and second drill temperatures (β = 0.80, p  < 0.01) significantly influenced the final drilling temperature. However, the implant system (p = 0.39) was not a significant predictor of the final temperature.

Conclusion: The motor type and implant system have a major effect on the thermal changes that occur during surgical osteotomies. Clinicians should administer motor types and implant systems to minimize thermal damage to the bone; thus, the performance in dental implant surgeries can be improved. Therein, we have patient safety and longevity of dental implants.

Background: Periodontitis is a chronic immunoinflammatory disease involving various components that affect the tissues surrounding the tooth. The host immune response to the presence of periodontopathogenic microorganisms activates several cytokine systems involved in alveolar bone resorption in periodontitis; among them is the receptor activator of nuclear factor-κB (RANK)/receptor activator of nuclear factor-κB ligand (RANKL) system, which depends on the interleukin (IL)-23/IL-17 axis. There is a tendency toward increased IL-23, IL-17, and IL-17 receptor (IL-17RA) and a discrepancy in IL-23 receptor (IL-23R) in gingival tissue (GT) of patients with periodontitis. Therefore, the aim of this study was to quantify the expression of the IL-23/IL-17A axis using the western blotting (WB) technique in GT samples from patients with periodontitis.

Materials and methods: This cross-sectional study included 49 subjects: 25 healthy subjects and 24 subjects with periodontitis. GT samples were collected during periodontal surgery. WB was used to evaluate the levels of IL-23, IL-17A, IL-23R, and IL-17RA.

Results: We found a significant increase in IL-23, IL-17A, IL-23R, and IL-17RA protein levels in the periodontitis group compared with the healthy group; we also detected bands with unexpected molecular weights for both receptors. Moreover, we found a significant positive correlation between IL-23 and IL-17A with both receptors, while IL-23, IL-17A, IL-23R, and IL-17RA correlated positively with two periodontal clinical parameters, namely the clinical attachment level and the percentage of radiographic bone loss (%RBL).

Conclusion: In this study, we detected overexpression of IL-23, IL-17A, and their receptors in GT of patients with periodontitis, confirming that the IL-23/IL-17A axis is involved in periodontal disease.

Introduction: Climate change has led to a growing interest in environmental sustainability in the healthcare sector, including orthodontics. This review aims to analyze and compare the environmental footprint of traditional multibracket appliances (TMAs) and clear aligners (CAs), focusing on five aspects: manufacturing process, pollution from raw materials, clinical management, and recycling potential.

Materials and methods: A comprehensive literature search was conducted on different databases: PubMed, Scopus, Web of Science, Google Scholar, and ScienceDirect. In addition, a manual and gray literature search was performed. Included studies were reviews, systematic reviews, epidemiological studies, or life cycle assessment (LCA) addressing environmental aspects of orthodontic materials and treatments. The articles included in the review were then divided into the following categories: manufacturing processes, environmental impact of production, clinical management, and generation of waste with recycling potential.

Results: A total of 34 studies published between 2003 and 2004, along with academic books and technical/informational sources, were analyzed. The production of TMA materials relies mainly on stainless steel (SS) and alumina, while CA uses thermoplastic polymers such as polyethylene terephthalate (PET), glycol-modified PET (PET-G), and polyurethane (PU). Although SS production generates higher CO₂ emissions, it offers better recyclability. In contrast, CA materials production requires more energy and generates a larger amount of nonrecyclable plastic waste. The environmental impact is also influenced by the clinical management of these therapies, such as the time and frequency of visits.

Conclusion: Both systems contribute to environmental pollution. TMA appears more sustainable due to its recyclability and reduced waste generation. Future research should focus on improving recyclable polymers, sustainable production methods, and optimized clinical workflows.

Objective: To estimate the prevalence of edentulism and functional dentition (FD) in Brazil and assess the magnitude of inequalities among older adults, according to education in 2003, 2010, and 2023.

Methods: This study used repeated cross-sectional data from individuals aged 65-74 years who participated in the national oral health surveys (SB Brasil) conducted in 2003, 2010, and 2023. Edentulism was defined as the loss of all permanent teeth, and FD as the presence of 21 or more teeth. Educational level was categorized as: 0 (no schooling), 1-4, 5-8, 9-11, and ≥ 12 years of study. Absolute and relative inequalities in edentulism and FD were assessed using the slope index of inequality (SII) and the relative index of inequality (RII) based on education. Generalized linear models (GLMs) were applied with a logarithmic link function to estimate RII and an identity link function to estimate SII, adjusting for sex and age. The concentration index (CI) was calculated as twice the area between the concentration curve and the line of equality. All analyses accounted for the complex sampling design and sample weights.

Results: The study included 5347 individuals in 2003, 7619 in 2010, and 9745 in 2023. The prevalence of edentulism was 53.33% in 2003 and 53.38% in 2010. In 2023, the prevalence significantly declined to 36.47%. FD prevalence was significantly higher in 2023 (23.94%) compared with 2003 (9.89%) and 2010 (11.45%). A worse oral health status was observed among individuals with lower educational levels. Indicators of absolute and relative inequality showed a significant increase in disparities, confirmed by the CI.

Conclusion: There was an increase in inequalities in edentulism and FD, indicating that the reduction in tooth loss was greater among socioeconomically advantaged groups.

Objectives: The purpose of this study was to assess the effects of self-reported perception of facial and dental aesthetics on academic and social performance among dental students in Jordan.

Methods: Online and paper-based cross-sectional surveys were collected from 371 dental students distributed between the two dental schools in Jordan. The survey contained the five sections of the Psychological Impact of Dental Aesthetics Questionnaire (PIDAQ), then asked participants about the presence or absence of factors that compromise dental aesthetics, and information about academic scores and academic satisfaction.

Results: Results showed that facial and dental aesthetics had an impact on the social and academic performance of dental students in Jordan. Students who stated perceived factors compromising their dental aesthetics reported low levels of confidence when speaking and communicating with other people, lower grades, and low levels of satisfaction with overall academic performance.

Conclusions: Social and academic performance of dental students in Jordan were found to be significantly influenced by the aesthetic qualities of the self-reported facial and dental features. These findings highlight potential psychosocial impacts of perceived dental aesthetics, while acknowledging that other unmeasured factors may also contribute.

Objectives: Salivary constituents have a wide range of functions, including oral calcium homeostasis. Salivary proteins, such as statherin inhibit the crystal growth of calcium phosphate in supersaturated solutions and interact with several oral bacteria to adsorb on hydroxyapatite. Concurrently, saliva, which is supersaturated with calcium phosphates, is the driving force for plaque mineralization and calculus formation. The present study has, thus, been carried out to correlate salivary statherin and calcium concentration with dental calculus formation.

Materials and methods: The study comprised 90 participants (58 males and 32 females) aged 20-40 years. Participants were grouped according to the calculus index viz. Group I (control calculus index), Group II (low calculus index), and Group III (high calculus index). After collecting saliva, the salivary calcium and statherin levels were estimated for each participant, and the data were entered into a master chart.

Results: The mean salivary statherin levels were found to be 1.305 ± SD 1.302, 0.986 ± SD 0.591, and 1.21 ± SD 0.473 in Groups I, II and III, respectively. The calcium levels increased from Group I to Group III (2.221, 5.067, and 10.072 mg/dL, respectively). Salivary calcium levels showed a significant positive correlation with the calculus index (0.639) (p < 0.001).

Conclusion: Salivary concentrations of calcium appear to play an essential role in the dental calculus formation. Salivary statherin exhibited a statistically nonsignificant, modest negative correlation with both calcium concentrations and the development of calculus.

Statement of the problem: Retention is still a primary concern in conservatively managing short clinical crowns (SCC) and minimal restorative space. In modern dentistry, there is a growing expectation for the durability and retention of indirect restorations, along with a high esthetic demand, even in unfavorable underlying conditions.

Purpose: This study aims to establish a reliable approach for the conservative treatment of SCCs using monolithic zirconia crowns (MZC).

Materials and methods: Sixty human molars were collected and mounted in resin blocks. The teeth were prepared with two different abutment heights (2 and 4 mm). MZCs with buccal and lingual projections were designed and milled after digital scanning. Half of the restorations were cemented with TheraCem (TC) calcium silicate-based self-adhesive resin cement, while the remaining half were cemented with glass ionomer (GI) cement. The specimens underwent thermocycling and cyclic loading. A traction test was then performed in the universal testing machine to evaluate the debonding forces. Data was analyzed using Pearson correlation and one-way ANOVA tests.

Results: A strong positive correlation was shown in Pearson analysis between the assigned group and the pull-out force (r = 0.95, p-value ≤ 0.01). In addition, ANOVA found a significant mean difference in the pairwise comparison of groups. Increasing abutment height in groups with either GI or TC cement type resulted in increased measured force. More importantly, TC groups have shown a greater average value than specimens with GI cement.

Conclusions: We demonstrated the significant influence of TC cement on the pull-out force measurement, outperforming the GI cement. The abutment height also showed a smaller contribution to the force measurement. Low-thickness monolithic zirconia restorations cemented with self-adhesive resin cement can be recommended as a reliable and effective treatment option for clinicians managing cases with SCCs and compromised retention.

Objectives: This study assessed the effects of remineralizing agents on microhardness and mineral content of primary enamel following iron drop exposure.

Materials and methods: In this in vitro study, 36 sound primary anterior teeth were randomly assigned to four groups (n = 9) of (I) casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), (II) fluoride varnish, (III) MI varnish, and (IV) control. The microhardness of specimens was initially measured by a Vickers hardness tester. The specimens were immersed in iron drop solution in a shaker incubator at 37°C for 5 min. They were then rinsed with distilled water, and their microhardness was measured again. The teeth were subsequently split in half. The buccal halves were exposed to the remineralizing agents for 4 h, rinsed with distilled water, and immersed in artificial saliva for 24 h. They were then immersed in a demineralizing solution for 6 h, followed by a remineralizing solution for 18 h at 37°C for 10 days. The final microhardness was measured again. The buccal and lingual halves underwent energy dispersive X-ray spectroscopy for mineral content analysis. Data were analyzed by one-way ANOVA and Tukey test (α = 0.05).

Results: Iron drop exposure significantly decreased, and remineralizing agents significantly increased the microhardness (both p  < 0.001). The three remineralizing agents had no significant difference in enhancement of microhardness (p = 0.493). The four groups had significant differences in Ca, F, and Fe contents after the intervention (p  < 0.05).

Conclusion: Iron drop exposure decreased, and remineralizing agents increased the microhardness and mineral content of primary enamel under in vitro conditions.

Background: Molar incisor hypomineralisation (MIH) is a developmental enamel defect that predominantly affects first permanent molars and frequently involves incisors. However, evidence on MIH prevalence and clinical presentation in jungle regions is limited.

Aim: To determine the distribution and clinical patterns of MIH among schoolchildren in the Central Jungle region of Peru.

Materials and methods: This cross-sectional study included 1500 schoolchildren aged 6-12 years from two public schools in Peru's Central Jungle region, recruited through stratified random sampling. Two calibrated examiners diagnosed MIH using European Academy of Paediatric Dentistry (EAPD) criteria (inter-examiner κ = [0.87]; intra-examiner κ = [0.89]). Categorical variables were analysed using Pearson's chi-squared and Fisher's exact tests (α = 0.05, 95% CI).

Results: MIH prevalence was 18.8% (95% CI: [17.0-20.0]). First permanent molars were predominantly affected (upper: 84.8%, 285/336; lower: 90.9%, 288/317) compared to incisors. Pattern I distribution occurred in 78.7% of cases, while patterns II/III (21.3%) showed significant male predominance (p = 0.008). Molars exhibited significantly greater severity (p = 0.001) with white-cream opacities (28.5%) and predominantly Type III lesions, presenting higher post-eruptive breakdown and atypical caries rates. Incisors displayed mainly mild Type I demarcated opacities. Upper lateral incisors demonstrated left-sided predominance (p = 0.016).

Conclusion: MIH prevalence was 18.8% among schoolchildren in Peru's Central Jungle region. First permanent molars were predominantly affected (upper: 84.8%; lower: 90.9%) compared to incisors. Pattern I distribution occurred in 78.7% of cases, while patterns II/III (21.3%) showed significant male predominance. Molars exhibited greater clinical severity with white-cream opacities, Type III lesions, and higher rates of post-eruptive breakdown and atypical caries, whereas incisors presented mainly mild demarcated opacities.

Background: The strength of the binding between the acrylic denture teeth and the foundation materials of dentures has been found to vary.

Objectives: Analyze the various adhesives and polymerizing techniques used to attach acrylic denture teeth to the acrylic denture base.

Methods: Tooth preparation and curing were done using heat-cured and microwave-cured (Acron Mc) acrylic resin. The 60 teeth were divided into six groups and subjected to different surface treatments. The second group was given diatoric preparation, the third group thinner, the fourth group acetone, the fifth group diatoric acetone conditioning, and the sixth group diatoric thinner conditioning. The control group was left untreated. The mesiodistal retention grooves of the second, fifth, and sixth groups were 2 mm deep and 3 mm wide, significantly affecting (p  < 0.01) the ridge laps of the acrylic denture teeth. The specimens were stored for 10 days at 37°C in distilled water before testing. The specimen was then visually evaluated after being broken by shear force delivered by an Instron universal testing machine.

Results: The study revealed that the microwave-cured acrylic denture base displayed higher shear bond strength (SBS) compared to the heat-cured resin, regardless of the surface treatment applied. The outcomes indicated that the microwave-cured resin had notably lower mean values of SBS for all acrylic denture teeth in comparison to the heat-cured resin.

Conclusions: The microwave-cured resin had significantly lower mean SBS values than the heat-cured resin. The sixth group had the largest SBS compared to the other groups at the p-value < 0.05. Unlike previous studies, this work incorporates a comparative evaluation of combined mechanical and chemical treatments (grooves with thinner conditioning and acetone), aiming to generate clinically applicable modifications for enhancing denture longevity.