Restorative Dentistry & Endodontics最新文献

Objectives: : This study aimed to evaluate the efficacy of three commercially available desensitizing agents in occluding dentinal tubules, which may help reduce tooth sensitivity following a bleaching treatment.

Methods: Twenty healthy human third molars were utilized in this investigation. The samples were prepared by transversely sectioning 2.5 mm of the crowns to expose the dentin. They were initially treated with 15% ethylenediaminetetraacetic acid gel for 4 minutes, followed by application of Perfect Bleach (VOCO GmbH) bleaching agent (16% carbamide peroxide) for 2 hours. The samples were randomly allocated into four groups (n = 5), each receiving one of the following treatments: group 1: No treatment (control), group 2: treated with UltraEZ (Ultradent Products Inc.,), containing potassium nitrate and sodium fluoride, group 3: treated with Perfect Protect (VOCO GmbH), also containing potassium nitrate and sodium fluoride and group 4: treated with TheraSol Whitening & Sensitive (ABC Kinitron IKE), containing strontium acetate and sodium monofluorophosphate. Subsequently, the specimens were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy to evaluate dentin tubule occlusion.

Results: SEM observations showed no occlusion of dentin tubules in the control group, whereas groups 2 to 4 exhibited significant occlusion. The most effective treatment was Perfect Protect (p < 0.05), while UltraEZ and TheraSol Whitening & Sensitive demonstrated similar effectiveness, with no statistically significant difference between them (p > 0.05).

Conclusions: The tested desensitizing agents effectively occluded dentin tubules to a considerable extent. Differences in their effectiveness were attributed to variations in their formulations.

Objectives: : Universal adhesives (UAs) are marketed as versatile systems for both self-etch (SE) and total-etch (TE) modes. While their bond strength has been widely investigated, evidence linking fracture characteristics to bonding performance remains limited. This study evaluated the micro-shear bond strength (μSBS) and failure patterns of three UAs applied in SE and TE modes, complemented by fractographic scanning electron microscopy (SEM) analysis.

Methods: Eighteen extracted human molars were sectioned to expose mid-coronal dentin and randomly allocated to SE or TE application. Three UAs were tested: Tetric N-Bond Universal, All-Bond Universal, and Single Bond Universal (SBU). Composite micro-rods (n = 72) were bonded, thermocycled for 500 cycles between 5°C and 55°C, and subjected to μSBS testing. Fracture surfaces were examined under SEM and classified as adhesive, cohesive, or mixed. Data were analyzed using two-way analysis of variance, Tukey post hoc test, and Spearman correlation (α = 0.05).

Results: In TE mode, SBU demonstrated the highest μSBS (p < 0.001), whereas no significant differences were observed among adhesives in SE mode (p > 0.05). SEM analysis revealed adhesive failures as interfacial fractures, cohesive failures with beach marks, and mixed failures involving crack propagation through both dentin and composite. Adhesive failures correlated negatively with μSBS (rs = -0.77), while mixed failures correlated positively (rs = 0.81).

Conclusions: Both the etching strategy and adhesive formulation significantly affect bond strength and fracture behavior. Fractographic SEM analysis provides critical insights into the mechanical reliability of UAs and informs their clinical application.

This case report presents a lateral maxillary incisor with dens invaginatus (DI) type IIIb that was treated both nonsurgically and surgically over 50 years. Treatment of teeth with DI can be challenging. Suggested options may include nonsurgical root canal treatment, endodontic surgery, or extraction. In this case report, a 13-year-old patient with a lateral maxillary incisor with DI type IIIb was treated by nonsurgical root canal treatment, modern endodontic surgery, and reoperation over the course of 50 years. There was complete healing at the last follow-up, 11 years after the reoperation. Correct diagnosis and proper treatment using modern endodontic techniques can enable teeth with DI to survive throughout the life span of the patient.

Objectives: : This study aimed to evaluate the actual parameters of four endodontic motors, each adjusted for reciprocating motion, and compare them to the manufacturers' declared values.

Methods: The motors used were the VDW Silver Reciproc (VDW GmbH), E-Connect Pro (MK Life), Ecom (Woodpecker), and Endopen (Schuster Woodpecker). A custom optical target was attached to the motor contra-angle, the movements were recorded with a high-resolution camera, and the images were analyzed. Engagement, disengagement, net angles, and speed for each operation cycle, duration of clockwise (CW) and counter-clockwise (CCW) movement, duration of standstill after CW and CCW movement, and the number of cycles to complete a full rotation were analyzed. The data were statistically analyzed at a significance level of 5%. The replicability of all reciprocal parameters analyzed was statistically different from that reported by the manufacturers.

Results: There was no statistically significant difference between the VDW Silver Reciproc, Ecom, and Endopen for the engagement angle. The E-Connect Pro was the least reliable at the 150°/30° settings for both angle parameters. There was no significant difference between the set and actual cycle net angles for the VDW Silver Reciproc (p = 0.493). While the actual values for the Ecom and E-Connect Pro were significantly higher than the set (p < 0.001), the actual values for the Endopen were significantly lower than the set (p < 0.001).

Conclusions: Experiments on four commercially available reciprocating endodontic motors revealed that the actual motor values differed significantly from the set values.

Objectives: : This study analyzed the root and canal configurations of maxillary premolars in a Jordanian subpopulation using cone-beam computed tomography (CBCT) and classified them based on Vertucci's and Ahmed's systems.

Methods: Two hundred CBCT scans of 800 maxillary premolars were retrospectively assessed for root morphology, canal configurations, and root canal divergence and merging. Data was statistically analyzed.

Results: The study included 70 males and 130 females. Most right and left maxillary first premolars (RFPM, LFPM) had two roots (59.0% and 58.5%), with a significant association between sex and root number for RFPM and LFPM (p < 0.05). In contrast, the right and left maxillary second premolars (RSPM, LSPM) mostly had a single root (87.5% and 88.5%), with no association with sex. Vertucci's classification showed type IV as the predominant configuration in first premolars (RFPM, 65.0% and LFPM, 67.0%) and type I in second premolars (RSPM, 44.0% and LSPM, 49.0%). A significant sex association was found only with RSPM. Ahmed's classification revealed that maxillary premolar with two separated roots and two separated canals (2MP B1 P1) was mostly found in first premolars (RFPM, 58.0% and LFPM, 56.0%), and maxillary premolar with one root and one canal (1MP1) in second premolars (RSPM, 44.0% and LSPM, 49.0%), with a significant sex association for RSPM and LSPM (p < 0.05). Age had no impact, and symmetry was observed between the right and left sides. Three-rooted premolars were identified in four cases. Almost all of Vertucci's types and numerous codes from Ahmed's classification were documented.

Conclusions: CBCT revealed diverse anatomical variations in the Jordanian subpopulation, with Ahmed's classification providing more detailed canal configurations than Vertucci's, uncovering previously overlooked variations.

Objectives: This study aimed to quantify light attenuation through varying tooth thicknesses and its impact on the depth of cure of composite resin.

Methods: Twenty extracted premolars were used to create enamel-dentin discs that were sanded progressively in 0.5 mm increments from 2.5 mm to 0.5 mm. Light irradiance was measured with and without tooth specimens to evaluate light transmittance. Resin was cured beneath different thicknesses, and the depth of cure was assessed using the Vickers hardness test.

Results: The results demonstrated that light transmittance significantly decreased as tooth thickness increased (p < 0.01), leading to reduced resin polymerization. In the 2.0-mm and 2.5-mm tooth thickness groups, the depth of cure was significantly lower than in the control group without tooth specimens (p < 0.05).

Conclusions: Ultimately, for tooth structures exceeding 2 mm, self-cure or dual-cure resin polymerization is thought to be more efficient than light polymerization.

Objectives: The aim of this systematic review is to compare the effectiveness of advanced platelet concentrates as regenerative endodontic therapeutic alternatives to blood clot (BC) revascularization in immature permanent necrotic teeth.

Methods: Randomized controlled trials (RCTs) comparing regenerative endodontic therapies using platelet-rich plasma (PRP), platelet-rich fibrin (PRF), or platelet pellet (PP) with the BC revascularization approach in immature permanent necrotic teeth were systematically searched in PubMed, Scopus, Cochrane Library, and Web of Science until May 2025. Data was extracted and analyzed both qualitatively and quantitatively. Study quality was assessed using the Cochrane Risk of Bias tool. A meta-analysis was conducted using IBM SPSS software (version 29.0), with success rates expressed as risk ratios and 95% confidence intervals (CIs).

Results: The initial search yielded 4,917 studies. After removing duplicates and applying eligibility criteria, 15 RCTs were included. Meta-analysis indicated no significant difference in the risk ratio (RR), as the BC method has similar success rates with PRP (10 studies; RR = 1.01; 95% CI, 0.94-1.09; p = 0.76) and PRF (8 studies; RR = 0.98; 95% CI, 0.89-1.08; p = 0.65) at 12 months. The primary outcomes evaluated were based on clinical and radiographic success.

Conclusions: Current evidence suggests PRP, PRF, and BC are all effective in treating immature permanent necrotic teeth with similar success rates. However, further research is needed to assess long-term outcomes.

Objectives: This study evaluated the marginal adaptation of ProRoot MTA (Dentsply Tulsa Dental), Biodentine (Septodont), and TotalFill BC RRM (FKG) placed in root-end cavities prepared with ultrasonic or Er,Cr:YSGG laser tips, using scanning electron microscopy.

Methods: The canals of 90 extracted maxillary central incisors were prepared and obturated and their roots resected. Six groups of 15 specimens were allocated as follows: ultrasonic + ProRoot MTA, ultrasonic + Biodentine, ultrasonic + TotalFill, laser + ProRoot MTA, laser + Biodentine, and laser + TotalFill. Roots were sectioned longitudinally to expose the filling material. Apical and coronal micrographs were taken, and the greatest distance between dentin and filling material was measured. The total gap area was also calculated using further micrographs.

Results: Cavities prepared with the ultrasonic tips and filled with Biodentine showed significantly greater gap dimensions compared with TotalFill (p < 0.001) and ProRoot MTA (p = 0.007) in the apical region. The ultrasonic group showed significantly higher void values compared to the laser group for ProRoot MTA (p = 0.026), when comparing the total values of void. The Biodentine group was significantly higher than the TotalFill group in root-end cavities prepared with ultrasonic tips (p < 0.001). The Biodentine group was significantly higher than the ProRoot MTA group in root-end cavities prepared with the laser tip (p = 0.002).

Conclusions: Under the conditions of this study, it was determined that the root-end cavity preparation technique had an effect on the amount of gaps formed between the dentin and the three filling materials.

Objectives: The objective of this study was to evaluate the effects of transformational temperatures on the cyclic fatigue resistance at body temperature of reciprocating file systems: R motion (RM), Procodile Q (PQ), and Reciproc Blue.

Methods: Resistance test was done in a custom-made device at room (20°C ± 1°C) and body (37°C ± 1°C) temperatures within a 60° angle of curvature and 5 mm radius of the artificial canal. The time to fracture (TTF) was recorded. The scanning electron microscope observation and differential scanning calorimetry analyses were performed. Two-way analysis of variance and Tukey post-hoc comparison were applied at a significance level of 0.05.

Results: The results showed a significant influence of temperature on instrumental breakage, regardless of the file systems (p < 0.05). The TTF is significantly decreased at body temperature (p < 0.05). PQ showed the longest TTF in both temperature conditions (p < 0.05). RM demonstrated a significantly higher TTF reduction ratio compared to the other files (p < 0.05).

Conclusions: Within the limitations of this study, the heat-treated files with reciprocating kinetics may have different reduction ratios of the fatigue resistance of the file systems under different temperature conditions. This characteristic is an important point of consideration when clinicians select the file system to reduce potential file fracture.

Objectives: This study aimed to analyze the temperature changes during the light curing of conventional flowable composite resin and bulk-fill composite resin of various thicknesses using an infrared thermographic camera.

Methods: Flowable composite resin (G-aenial Flo, GC Co.) and bulk-fill composite resin (SDR, Dentsply Caulk) were used. Specimens with thicknesses from 0.5 mm to 5.0 mm were prepared. The infrared thermographic camera measured the temperature changes at the maximum temperature rise point during light curing. The data were analyzed for maximum temperature, time to peak temperature, and temperature rise patterns.

Results: For G-aenial Flo, the maximum temperature tended to decrease with increasing thickness, whereas for SDR, the maximum temperature decreased up to 2.0 mm and then remained relatively consistent from 2.0 mm to 5.0 mm. At thicknesses of 1.5 mm or less, both resins showed a rapid temperature increase within the first 5 seconds, followed by a reduced rate of increase up to 80 seconds. At thicknesses of 2.0 mm or greater, the temperature peaked and then gradually decreased. Across all thicknesses, SDR was observed to reach peak temperature more rapidly than G-aenial Flo.

Conclusions: Observable differences in polymerization dynamics were identified between the two resin types, particularly at greater thicknesses. Although no statistical analysis was performed, these descriptive findings suggest that infrared thermographic cameras may be useful for indirectly assessing polymerization dynamics during resin polymerization.