Quintessence international最新文献

Objectives: Tooth mobilization is a challenging orthodontic treatment. Inadequate interdisciplinary communication between surgery and orthodontics, as well as limited knowledge of the topography of the surgical field, can lead to unfavorable positioning of the appliance. This can result in dangerous force vectors for tooth movement. Comprehensive digital planning and customized tools could reduce these sources of error. Two cases of impacted canines were treated using cutting guides and customized attachments.

Method and materials: A CBCT and intraoral scan were taken for planning. A CAD process was used to design a cutting guide and a customized attachment according to the required force vectors (OnyxCeph3, Image Instruments). Using various CAM processes, the cutting guide (BioMed Clear Resin, Formlabs) and a customized attachment dummy (Permanent Crown Resin, Formlabs) were fabricated in a 3D printer (Form 3B, Formlabs). The customized attachment was fabricated from titanium using the selective laser melting process (OrthoLIZE). The teeth were surgically exposed using the cutting guide and customized attachment dummies. The customized attachment was conventionally cemented using Transbond XT (3M Unitek).

Results: All teeth were successfully exposed with the cutting guides. The customized attachments could only be placed in the predetermined position according to the digital planning.

Conclusion: The 3D planned cutting guide can help to shorten the surgical procedure and keep the surgical field as small as possible. The 3D planned customized attachment allows precise positioning. The digitally planned force vectors should prevent side effects on adjacent teeth and allow targeted mobilization. However, studies are needed for further validation.

Objectives: With little evidence and controversial guidelines on space maintainers, this cross-sectional population-based study aimed to analyze the prevalence and distribution of space loss after premature extraction of primary molars and the potential effect for space maintainers.

Method and materials: Within the compulsory dental examinations in all primary schools in Greifswald, Germany, 6- to 12-year-old children were screened for premature loss of primary molars. The mesiodistal dimension at the site of extraction and the contralateral tooth were measured with Zürich calipers by two calibrated examiners.

Results: Out of 1,596 students, 190 (11.9%) exhibited early loss of primary molars (47.9% females, mean age 8.73 ± 1.02 years). In total, 152 of 291 missing molars that were lost unilaterally were suitable for comparison with the intact side. Only 26 students had a space maintainer (8.9%). There was a statistically significant difference in space loss after premature extraction of primary molars with and without space maintainer (mean 0.59 ± 0.94 mm vs 1.66 ± 1.66 mm, respectively, P = .037). This was especially true for second primary molars (2.62 ± 1.93 mm; first molars 1.17 ± 1.30 mm; P .001). Space loss in the maxilla (1.75 ± 1.68 mm) was slightly higher than in the mandible (1.40 ± 1.58 mm, P = .187). In total, 53.3% of the children exhibited minimal space loss (≤ 1 mm), and 22.4% experienced 2.5 to 7.0 mm space loss.

Conclusion: More than 10% of a low caries-risk population exhibited premature extraction of at least one primary molar. Space loss was greater in the region of second primary molars, while space maintainers significantly reduced space loss. Due to the complexity and variation of space loss, decision making on space maintainers should be individualized.

Objectives: Various salivary cytokines are overexpressed in the saliva of Sjögren disease patients. In addition, the levels of salivary cytokines can differ according to local and systemic conditions, besides Sjögren disease itself. This study aimed to analyze the associations and correlations of caries experience, sialometry, and systemic comorbidities with levels of the following salivary cytokines: interleukin (IL) 1β, IL-6, IL-8, IL-10, TNF-α, and IL-17A among Sjögren disease patients.

Method and materials: Upon ethical approval and signed informed consent, 20 women with Sjögren disease were recruited. Clinical examinations included decayed, missing, or filled teeth (DMFT) Index measurements, sialometry, and saliva sampling. Levels of salivary cytokines IL-1β, IL-6, IL-8, IL-10, tumor necrosis factor-α (TNF-α), and IL-17A were measured by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed using the independent-samples Mann-Whitney U test for the associations between the categorical parameters, and Spearman correlation test to analyze the correlations between continuous variables.

Results: Salivary cytokines were inter-correlated in a statistically significant manner (P .05). Age correlated with IL-17A levels (P .05), and decayed teeth correlated with IL-6, IL-8, and IL-10 (P .05). The liquid fraction in the unstimulated salivary flow rate significantly correlated with all salivary cytokines that were measured. Cardiac disease correlated with IL-10 levels, and rheumatoid arthritis correlated with IL-1β levels (P .05).

Conclusions: These results suggest that local factors such as caries experience and salivary flow rates as well as systemic factors such as comorbidities should be taken into consideration when testing the levels of salivary cytokines in Sjögren disease.

Objectives: This retrospective study assesses the long-term effects of implants on alveolar and basal bone to determine if a patient's sex affects dimensional changes in the jaw and evaluate whether dental implants halt the atrophy of bone when compared to no post-extraction intervention.

Method and materials: Institutional Review Board approval was obtained for this study. Of the 125 patients (432 sites) in the study, 53% were women. All had two CBCTs taken, an average of 4.7 years apart. The scans were divided into three groups. In the control group, the extraction site (first CBCT, T1) was not replaced when the second scan was taken (T2). Group 2 had no implant at T1 and an implant at T2. Group 3 had an implant at T1 and T2. Measurements were made from landmarks at predetermined levels (superior cortex of the inferior alveolar nerve or the most inferior point in the nasal floor in the direction of the crest of bone height (control group and groups 2 and 3). To avoid osseous changes due to placement, measurements were made from the inferior alveolar nerve for mandibular implants or the nasal floor for maxillary implants. Recognizing sex-based disparities in jaw size, percentage changes in bone were monitored.

Results: Loss of alveolar bone width across all groups was common. When bivariate analysis was performed after Bonferroni correction (P .025), changes in alveolar bone width were significantly greater in women (P = .004). Although the loss in the basal bone was present, it was not significant between the sexes nor as great as alveolar bone resorption (P = .880). When comparing groups using bivariate analysis, differences were not statistically significant between treatment groups and the control group (P = .050) for basal bone and for alveolar bone (P = .052). In the regression analysis for sex or group, neither was statistically significant for either basal or alveolar bone (P > .05).

Conclusion: Dental implants do not arrest post-extraction atrophy in either alveolar or basal bone. Women exhibited a statistically greater rate of alveolar bone loss. Stable long-term implant success necessitates precise placement.

Objectives: Pathologic root resorption in primary teeth affects dental health and future orthodontic needs. This study aimed to evaluate the prevalence and associated factors of pathologic root resorption in a pediatric population.

Method and materials: A retrospective cross-sectional analysis was performed using panoramic radiographs from 691 pediatric patients aged 4 to 11 years at a university hospital in Türkiye. Teeth were evaluated for internal (IRR) and external pathologic root resorption (ERR) by two calibrated observers, adhering to the 2023 European Society of Endodontics Position Statement. Tooth status was categorized as healthy, carious (with or without pulp involvement), filled, or endodontically treated, and dental crowding was also recorded. Statistical analyses included chi-square tests, multiple logistic regression, and post-hoc analyses, with significance set at P < .05.

Results: A total of 7,729 primary teeth (5,075 molars and 2,654 canines) were evaluated, with interobserver reliability of 82% and intraobserver reliability of 98.8%. The study cohort included 691 children (mean age 7.05 ± 1.45 years; 49.8% boys, 50.2% girls). Pathologic root resorption was observed in 21.2% of cases (n = 1,638), with ERR accounting for 81% and IRR for 19%. Among 2,654 healthy teeth, 3.76% exhibited pathologic resorption, with no significant association with dental crowding. Significant relationships were identified between pathologic root resorption and age (P = .000), tooth status (P = .049), and sex (P = .042).

Conclusion: Reducing high caries levels in Türkiye is critical to lowering pathologic root resorption and associated complications. Further studies should explore dental crowding and pathologic root resorption relationships in larger samples.

Objective: The aim of this retrospective study was to evaluate the effects of high preoperative C-reactive protein (CRP) levels on early peri-implant alveolar bone loss.

Method and materials: Fifty-eight implants in 20 patients with high preoperative CRP levels and 54 implants in 20 patients with low preoperative CRP levels were evaluated. For measurement of the peri-implant alveolar bone loss, the implant platform was accepted as the reference point. On both the mesial and distal sides, the vertical distances between the reference point and the first visible bone's highest coronal level were measured. Numerical data were compared between groups using the independent sample t test or the Mann-Whitney U test. Correlations between variables were investigated with the Spearman rho test.

Results: The mean CRP level of the low CRP group was 0.37 ± 0.21 mg/L, while that of the high CRP group was 1.71 ± 0.60 mg/L. In the high CRP group, implant failure was observed in two patients. The mesial bone loss and distal bone loss values in the group with high CRP levels were found to be significantly higher than the group with low CRP levels (P < .05). There was a significant positive correlation between the CRP levels, and distal bone loss and mesial bone loss measurements.

Conclusion: The results show that high preoperative CRP levels result in an increased risk for peri-implant alveolar bone loss, and suggest that preoperative CRP levels can be important for early peri-implant alveolar bone loss.

Nowadays, complication-free wound healing processes are the key to successful treatment outcomes in the context of periodontal and implant surgery, both clinically and scientifically. The main challenge here is to achieve primary wound healing in the majority of cases. Among the scientifically documented factors that influence the healing process, it is primarily the blood supply in the surgical area and the stability of the wound achieved postoperatively that can be directly influenced by the clinician. The surgical wound closure plays a decisive role in this context in order to achieve sufficient stabilization of the wound without negatively affecting the healing process through unnecessary traumatization of the tissue or excessive tensile forces on the wound edges. It is important to bear in mind that wound healing after surgical procedures in the oral cavity does not take place under optimal conditions. A moist, microbiologically contaminated environment is present and complete immobilization of the wound is hardly possible during the early healing phases. The sutures must therefore ensure that the surgical flaps are passively secured in the intraoperatively established position, that the wound edges are in as close contact as possible - especially if grafts that initially rely on nutrition through plasmatic circulation are used - and that the wound is stabilized during the first few postoperative days. The suture material and suturing technique must be selected so that the knots do not loosen and both the suture material and soft tissue can withstand the mechanical stresses during the early wound healing phases. The search for available mechanical anchors should be the focus of interest.

Objectives: This study aimed to evaluate the physical-mechanical behavior of resin composites when subjected to different prolonged heating protocols.

Method and materials: A total of 150 specimens were divided into 15 groups (n = 10 per group) based on the restorative materials (Filtek Supreme, VisCalor, and Grandioso) and heating protocols: room temperature (22°C), 24 hours at 68°C, 7 days at 68°C, 30- and 100- cycles of artificial aging by thermocycling (5 and 68°C for 10 minutes each). The materials were inserted into a PVS matrix, cured for 20 seconds using a 1,000 mW/cm2 LED light-curing unit, and stored for 24 hours. The response variables measured were flexural strength and Knoop microhardness.

Results: The flexural strength evaluation showed that Grandioso exhibited higher strength compared to Filtek Supreme and VisCalor, with no significant differences observed across the heating protocols. This indicates that prolonged heating did not affect the flexural strength of any of the tested resins. Knoop microhardness testing revealed significant differences among resins and heating protocols. Grandioso demonstrated the highest surface hardness across all protocols, whereas Filtek Supreme showed a decrease in hardness after 100 thermocycling cycles. Prolonged heating reduced surface hardness for Grandioso and VisCalor compared to room temperature, whereas Filtek Supreme maintained its hardness under extended heat exposure.

Conclusion: These findings suggest that while flexural strength remains unaffected by heating, surface hardness varies depending on the resin type and the heating duration.

Objectives: To analyze the effects of three osteotomy drill designs (conventional, reverse helix, and densification) and running directions on heat generation, primary implant stability, block-to-implant contact, peri-implant block volume, and resistance to unscrewing forces in a low-density alveolar bone model.

Method and materials: Eighty-eight dental implants were placed in artificial bone blocks using manual and computer-controlled osteotomies. Temperature changes, insertion torque value, resonance frequency analyses (implant stability quotient [ISQ]), block-to-implant contact, and peri-implant block volume were measured. Statistical analyses used ANOVA and Kruskal-Wallis tests (P < .05).

Results: Densification drill designs produced the lowest temperature change (17.52 ± 2.57°C and 28.06 ± 4.35°C for the second and third drills), while conventional drills had the highest (27.53 ± 5.17°C and 38.03 ± 8.08°C). Counter-clockwise (CCW) conventional drilling significantly reduced the temperature change compared to clockwise (CW). Densification drill designs achieved the highest primary implant stability (38.01 ± 1.87 N/cm, 65.00 ± 4.69 ISQ) and removal torque (25.40 ± 5.08 N/cm), while conventional CW drills had the lowest (33.23 ± 2.91 N/cm, 61.83 ± 4.28 ISQ). Densification drill designs showed the highest peri-implant block volume (87.71 ± 4.23 mm3) but the lowest block-to-implant contact (49.12 ± 2.93%). CCW conventional drilling improved insertion torque value over CW (36.21 ± 3.63 vs 33.23 ± 2.91 N/cm).

Conclusion: Densification drill designs demonstrated better performance in heat reduction, primary implant stability, and peri-implant block volume, but had lower block-to-implant contact. CCW running of conventional drills showed improvements over CW in several parameters. While densification drilling excelled in most aspects, its lower block-to-implant contact and the positive outcomes of CCW conventional drilling warrant further investigation.