Third Of Root Research Articles

Shaping ability of a pediatric motor-driven instrumentation system in primary molar root canal prototypes.

Thirty specimens were scanned in micro-CT and divided into three groups according to the instrumentation type: pediatric motor-driven Sequence baby File (SBF); conventional motor-driven (Sequence Rotary File - SRF); manual K file. Instrumentation time was timed. After preparation, the specimens were scanned again. The pre- and post-instrumentation images were superimposed to measure the amount of root canal deviation and the resin remnant thickness. ANOVA followed by the Tukey test analyzed the comparisons between groups (p<0.05). No statistically significant differences occurred in root canal deviation among groups (p>0.05). There were statistically significant differences in the comparison among root thirds (p<0.001) but without significant differences in the interaction group vs. root third (p>0.05). Both motor-driven instrumentations showed statistically greater weariness than manual instrumentation (p<0.001), without significant significant differences between SBF and SRF. Motor-driven instrumentation had a shorter working time than manual instrumentation (p<0.001). Pediatric motor-driven instrumentation demonstrated good outcomes in relation to root canal deviation and amount of remnant structure, with shorter instrumentation time. SBF can be a suitable alternative for endodontic instrumentation in primary molars.

Evaluation of Bond Strength and Fracture Load of Teeth With Flared Root Canals Restored With Prefabricated, Anatomical, and Computer-aided Design and Computer-aided Manufacturing Fiber Posts.

This study compared the use of anatomical glass fiber posts using bulk-fill composite resin with computer-aided design and computer-aided manufacturing (CAD/CAM) milled glass fiber post in oversized root canals, through bond strength (BS) and fracture resistance (FR) tests (fracture load). A total of 48 mandibular premolars were selected, half of them had their crowns removed at the cemento-enamel junction (CEJ) and the other half were sectioned 2 mm above the CEJ. Subsequently, teeth were endodontically treated. After 1 week, the standard preparation of the canals was carried out, and the roots were divided into three groups (n=16), according to the use of different restorative techniques (control: prefabricated glass fiber post [PFP], direct anatomical glass fiber post [AFP], and CAD/CAM milled glass fiber post [MFP]). After luting procedures using Single Bond Universal and RelyX Ultimate (3M ESPE), for eight teeth in each group, six specimens were obtained (two slices from each root third: cervical, middle, and apical). For the remaining eight roots of each group, standardized preparations for metal-free crowns, milling of 5 mol% yttria-stabilized tetragonal zirconia polycrystalline, cementation of the crowns, and periodontal ligament simulation were performed. Then, for each group, the BS was evaluated through the push-out test, and the FR was evaluated in compression. The data obtained from BS were submitted to two-way analysis of variance (ANOVA; group vs root region) and Tukey (α=0.05) and from FR to one-way ANOVA (group) and Tukey (α=0.05). For the BS test, the MFP group was statistically superior to the PFP group in all root regions and was statistically superior to the AFP group only in the cervical region, being statistically similar in the middle and apical root regions. For the FR test, the MFP group was statistically superior to the PFP and AFP groups. The milled fiber post technique can be a legitimate alternative in the restoration of weakened roots with flared root canals.

Assessment of the root surface temperature during the use of intracanal agitation systems: In vitro study.

This study aimed to evaluate the temperature changes that the different methods of agitation of irrigants promote on the external dental root surface. Nine extracted human lower premolars were standardized by cone-beam computed tomography and used. The root canal was instrumented with a Reciproc 40.06 file. Temperature measurement was performed using K-type thermocouple sensors attached to the middle, cervical, and apical thirds of the teeth. The teeth had their roots immersed in distilled water at 37ºC, which were distributed into 3 experimental groups according to the mechanical agitation methods to be studied. US Group (n=3), Irrisonic Ultrasonic Tip activated through ultrasound; EC Group (n=3), Easyclean Tip coupled to a contra-angle low-speed handpiece; XP Group (n=3), XP-endo Finisher file coupled to an endodontic electrical motor. Temperature measurements were performed simultaneously with agitation and irrigation of intracanal irrigants. Statistical analysis was performed using SPSS software with a significance level of 5%. For multiple comparisons, the Tukey test was used. The association between mechanical agitation methods and root third was statistically significant. Regarding the temperatures recorded on the external surface of the roots, the ultrasonic tip was significantly higher than the XP-endo Finisher file and the Easyclean tip, which did not differ from each other. Regarding the ultrasonic tip, the external temperature in the middle third (39.46ºC) of the root was significantly lower than in the cervical (40.41ºC) and apical third (40.53ºC). None of the agitation methods of irrigants studied presented heating above 47ºC, and their use is safe for periodontal tissues.

Different Dentin Conditioning Protocols on Bond Strength of a Bioceramic Root Canal Filling.

Bioceramic-based sealers, in combination with bioceramic-coated gutta-perchas, have become more commonly used in root canal obturation. The present study aimed to assess the influence of laser-assisted dentin conditioning compared with conventional conditioning protocols on the push-out bond strength (PBS) of a bioceramic-based root canal filling. Sixty extracted mandibular premolars with one root canal were instrumented with EndoSequence rotary files up to size 40/0.04. Four types of dentin conditioning protocols were used: 1) 5.25% NaOCl (control), 2) 17% EDTA+5.25% NaOCl, 3) Diode laser-agitated 17% EDTA+5.25% NaOCl, 4) Er,Cr:YSGG laser irradiation+5.25% NaOCl. Teeth were obturated using the single-cone technique with EndoSequence BC sealer+BC points (EBCF). After having obtained 1-mm-thick horizontal slices from the apical, middle and coronal root thirds, push-out test was carried out, and failure modes were determined. The data were analyzed by two-way analysis of variance and Tukey's test with a significance level of p<0.05. The apical segments showed the highest PBS in all groups (p<0.05). In the apical segments, EDTA+NaOCl and diode laser agitated EDTA increased the PBS compared to the control (p=0.0001) and Er, Cr: YSGG laser (p=0.011 and p=0.027, respectively) groups. Both laser-used groups revealed significantly higher PBS values in the middle and coronal segments than EDTA+NaOCl (p<0.05). The bond failure was predominantly cohesive without any significant difference among the groups (p>0.05). Laser-assisted dentin conditioning had distinct effects on the PBS of the EBCF at different root segments. Although Er, Cr: YSGG was ineffective in the apical segments, generally, laser-assisted dentin conditioning affected PBS more favorably than conventional irrigation groups, with a more pronounced effect in the diode laser-agitated EDTA group.

The Effect of Nanosilver Sodium Fluoride on the Mechanical and Physiochemical Properties of Artificially Demineralised Dentin.

To synthesise and characterise nanosilver sodium fluoride (NSSF) and assess the effect of applying this formulation in vitro on artificially demineralised root dentin lesions, compared with the application of silver diamine fluoride (SDF), sodium fluoride (NAF) or no treatment, in terms of mechanical, chemical and ultrastructural properties. NSSF was prepared using 0.5 wt% chitosan solution. On 40 extracted human molars, the buccal aspect of the cervical thirds of roots were prepared and divided into 4 groups of 10 each: control (no treatment), NSSF, SDF and NaF (n = 10). The specimens were examined using scanning electron microscopy (SEM), atomic force microscopy (AFM), and x-ray photoelectron spectroscopy (XPS). Fourier transform infrared spectroscopy (FTIR), surface and cross-sectional microhardness and nano-indentation tests were performed to determine the mineral and carbonate content, microhardness, and nanohardness, respectively. Statistical analysis was performed to determine the differences between the different treatment groups for the set parameters using parametric and non-parametric tests. Tukey's and Dunnet's T3 post-hoc tests were further used for multiple comparisons between groups (α = 0.05). The control group (no treatment) was found to have statistically significantly lower mean scores for surface and cross-sectional microhardness compared with all other test groups (NaF, NSSF and SDF) (p < 0.05). Spearman's rank correlation test showed statistically insignificant differences between the mineral-to-matrix ratio (M:M) and carbonate content of all groups (p < 0.05). Treatment of root lesions with NSSF yielded comparable results to SDF and NaF under in-vitro conditions.

The Roughening Effects of Er:YAG, Nd:YAG and KTP Laser Systems on Root Dentin Surface

Objectives: Present study aimed to evaluate the roughening ability of different laser systems on the middle and apical third of roots. Materials and Methods: Sixty extracted human single-rooted single canal mandibular premolar teeth were randomly assigned to 3 groups (n=20). Standardized preparation and sterilization procedures were performed. The samples were irradiated with Er:YAG, Nd:YAG, and KTP laser systems. The laser irradiations (1.5 Watt) were applied with a spiral motion, starting 1 mm short of the apex and then moving coronally for 10 sec, interleaved with 15-sec recovery intervals for each irradiation. This process was repeated twelve times. The roots that were standardized in the same length and thicknesses were divided parallel to the longitudinal axis. Then, the middle and apical 1/3 surface roughness values of each root section were measured using a profilometer and SEM analysis was performed. The data obtained were analyzed using the two-way analysis of variance (ANOVA) and Tukey post-hoc tests. Results: According to measurements obtained from middle and apical 1/3 surfaces; Although, the statistically highest roughness value was determined after Nd:YAG laser (P &amp;lt; 0.05), the statistically lowest value was detected following the Er:YAG laser irradiation (P &amp;lt; 0.05). Conclusions: In light of the present study, all laser systems caused significant roughness surface. Therefore, laser systems should be carefully applied in human root canals.

Apexogenesis and Apexification - Review

The role of dental pulp in the development of the teeth. Young patients with infected or damaged tooth pulp still present a challenge among practitioners due to the degree of tooth development, more specifically the permanent teeth that have not completed their root development. At the time of eruption, only two thirds of the tooth root is developed. If there is a disruption of pulp vitality before the full root development, the root growth and dentin formation stop, resulting in reverse-tapered or flared roots and an opened apex, which will make the future root canal treatment difficult. In these cases, we can find teeth with short roots, very thin walls and an inadequate crown-root ratio. The thing root walls increase the risk of fracture. We currently have several therapies available to treat these teeth, which we will discuss further on.

Evaluation of root resorption in the lower incisors after orthodontic treatment of skeletal Class III malocclusion by three-dimensional volumetric measurement with cone-beam computed tomography.

To investigate the volumetric changes of the lower incisor roots in skeletal Class III orthodontic patients with anterior crossbite after premolar extraction therapy. Thirty-six adults, aged 18-28 years, had four-premolar extraction treatment. Pre- and posttreatment cone-beam computed tomography (CBCT) images were used to assess the thickness and height of alveolar bone, root volume, and length. A paired t-test was used to detect changes in root volume and length before and after treatment. Pearson's correlation analysis was applied to estimate the correlation between root volume and dentoskeletal morphology. Both the central and lateral incisors had intrusion and tipping movement after treatment. Compared with pretreatment data, root length decreased significantly. The lingual root volume of root cervical, apical third, and the labial root volume of the root apical third decreased significantly (P < .05), among which the percentage of tooth loss at the tip volume was the highest. The pretreatment height of the alveolar ridge crest, thickness of the alveolar bone, and type of incisor movement were related to the volume and length loss. Volume and length loss in the apical third of the lower incisor roots in skeletal Class III patients treated with a Class III bicuspid extraction pattern is common. The pretreatment height of the alveolar ridge crest, thickness of the alveolar bone, and type of tooth movement are related to the loss.

Prevalence and morphological analysis of isthmuses in mandibular molars of the Indian population: A micro-computed tomographic study.

This study evaluated the prevalence, configurations, and correlation of isthmuses at coronal, middle, and apical root 3rd in mandibular molars of the Indian population using micro-computed tomography μCT). One hundred and five permanent mandibular molar teeth were scanned under μCT. The axial sections were analyzed at the coronal, middle, and apical thirds of the root for isthmus types and classified according to Hsu and Kim's classification. Descriptive statistics for each isthmus type were calculated. The correlations between the apical, middle, and coronal thirds of the root were determined using Pearson's correlation coefficient. Type IV isthmus was the most common in the coronal third of the mesial root of mandibular 1st molar (42.9%), while Type V was prevalent in the coronal third of the mesial root of 2nd molar (42.9%). Type I isthmus was found to be highly prevalent in the middle 3rd (71.4%) and apical 3rd (61.9%) of mesial roots of 1st molars, and in the middle 3rd (71.4%) and apical 3rd (42.9%) of mesial roots of 2nd molars. Type V isthmus was the most prevalent in all the thirds of the distal roots of both 1st and 2nd molars, ranging from 40% to 50%. Furthermore, a strong correlation of 0.965 (P < 0.01) was found between the isthmuses in the apical and middle thirds of roots. There are variations in the prevalence and type of isthmuses across different sections of the root, including the presence of atypical isthmuses. Micro-CT with high-resolution imaging and three-dimensional reconstruction is crucial for investigating root canal morphology. Clinicians could benefit from considering demographic characteristics to better predict the presence of isthmus variations. The isthmus configurations and frequency differ at each section of mandibular teeth.

Effect of resveratrol pretreatment of radicular dentin on immediate and delayed pushout bond strength of fiber post luted using self-adhesive resin cement: An in vitro study.

To assess and compare the effect of resveratrol pretreatment of root dentin on immediate and delayed pushout bond strength (POBS) of fiber postluted using self-adhesive resin cement. Postspace was prepared in endodontically treated roots and randomly divided into two groups based on pretreatment rinse before fiber postcementation: Group 1: Distilled water Group 2: 1 mL of 10 mg/mL resveratrol solution for 1 min. Fiber posts were luted using self-adhesive resin cement. Among, two 1 mm slices of the coronal and middle third of root, one slice was subjected to immediate POBS using the universal testing machine and the other slice was subjected to POBS after storing in distilled water for 12 months. Resveratrol pretreatment showed significantly higher immediate POBS with more mixed failure than distilled water group. There was no significant difference in delayed POBS between the distilled water (mean: 7.07 MPa) and resveratrol pretreated group (mean: 8.20 MPa) with predominantly adhesive failure among them. There was significant difference between immediate and delayed POBS value of both the groups. Resveratrol pretreatment can be considered to improve bond strength stability of radicular dentin to self-adhesive resin cement.

A universal adhesive containing copper nanoparticles improves the bonding and mechanical properties of resin cement–root dentin interface: an in vitro study

The aim of this study was to evaluate the anti-MMP activity of two concentrations of copper nanoparticles (CuNp) and the effect of their addition to a universal adhesive system on resin cement-radicular dentin in situ degree of conversion (DC), elastic modulus (EM), nanoleakage (NL), and push-out bond strength (PBS). Anti-MMP activity was evaluated for several MMPs. Seventy-two roots of endodontically prepared human lower premolars were randomly divided into six groups according to CuNp concentration (0% [control], 0.1%, 0.2%) and adhesive strategy (etch-and-rinse [ER] and self-etch [SE]). Fiber posts were cemented, DC was measured using micro-Raman spectroscopy, the EM of the hybrid layer and adhesive layer was measured using a nano-indenter, the NL was evaluated by scanning electron microscopy, and PBS was tested at 0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey’s test (α = 0.05). CuNp demonstrated anti-MMP activity (p < 0.01). CuNp containing-adhesives showed significant increased DC (p = 0.01), increased EM in the hybrid layer and adhesive layer (p = 0.001), decreased NL values (p = 0.001), and increased PBS (p = 0.0001). Adhesive strategy was not statistically significant (p > 0.47). Usually, a significant difference among root thirds was observed, except for DC and NL when CuNp 0.2% was evaluated. This is the first in vitro study showing that the incorporation of CuNp in an adhesive is an achievable alternative that can provide anti-MMP activity and improve the mechanical and bonding properties to root canal dentin.

Influence of Coronal Flaring on the Shaping Ability of Two Heat-Treated Nickel-Titanium Endodontic Files: A Micro-Computed Tomographic Study.

Nickel-titanium (NiTi) usage is associated in endodontics with some complications including canal transportation. Centering ability of a NiTi file is the ability to stay centered in the root canal system during instrumentation. Any undesirable deviation from the natural canal path is indicated as canal transportation. A possible strategy to improve the centering ability of NiTi instruments is the pre-enlargement of the coronal third of the root canal to minimize coronal interferences. This procedure is known as coronal flaring. The aim of this study was to perform a micro-computed tomographic (micro-CT) evaluation of the effect of coronal flaring on canal transportation and centering ability of two heat treated nickel-titanium rotary instruments, 2Shape (Micro Mega, Besançon, France) and HyFlex CM (Coltène Whaledent, Altstätten, Switzerland). Thirty extracted mandibular molars with two independent mesial canals were selected and randomly instrumented (n = 15 canals) with One Flare (Micro Mega, Besançon, France) before HyFlex CM, HyFlex CM (without coronal flaring), One Flare before 2Shape and 2Shape (without coronal flaring). One Flare (Micro Mega, Besançon, France) was introduced 4 mm below the canal entrance for canals prepared with coronal flaring. HyFlex CM and 2Shape were used accordingly to manufacturers’ instructions. New files were used for each canal. During and after instrumentation, irrigation procedures were performed. Micro-CT images were obtained pre- and post-preparation to measure and record root canal transportation and centralization. They were reconstructed from root apex to canal orifices, generating approximately 1000 sections per specimen. The anatomical thirds were determined by dividing the number of cross-sectional slices by three. Root canal transportation and centralization were determined by Gambil method, and the mean values were analyzed by repeated measures analysis of variance followed by multiple comparisons of Bonferroni to compare the different instrumentations procedures and the root thirds (p < 0.05). As for root canal transportation, 2Shape reported significantly higher values compared to HyFlex CM in the cervical region independently from the coronal flaring. In the apical region, 2Shape caused significantly minor canal transportation when used with coronal flaring with compared with the absence of coronal flaring. Regarding the centralization, HyFlex CM showed higher values than 2Shape in the cervical, independently from coronal flaring. In the apical region, 2Shape with coronal flaring exhibited significant major centering ratio, compared with not. Within the limitations of this study, coronal flaring reduced canal transportation and improved centralization of the 2Shape files in the apical section while it had no significant influence on shaping ability of the HyFlex CM instruments. Coronal flaring could represent a valid strategy to improve the shaping ability of NiTi files knowing that its benefit could be influenced by the shaping file used.

Influence of different adhesion strategies on glass fiber post retention.

Failures in glass fiber post (GFP) retention may be associated with low adhesion achieved in root dentin. 55 single-rooted premolars were endodontically treated and distributed according to different adhesion strategies (n=11): G1: RelyX ARC (3M ESPE; etch-rinse strategy); G2: Relyx Ultimate (3M ESPE; etch-rinse strategy); G3: AllCem (FGM; etch-rinse strategy); G4: Relyx Ultimate (3M ESPE; self-etching strategy); G5: RelyX U200 (3M ESPE; self-adhesive strategy). For Bonding Strength (BS) analysis, the roots were sectioned in slices (1.0mm thickness) corresponding to each root third and submitted to push-out test. The type of failure was assessed by scanning electron microscopy (SEM). The highest BS averages were found in G2 and G3. However, in the middle and apical root thirds, G3 showed statistically similar results to G4 and G5. In the cervical and middle third, G1 was statistically similar to G4 and G5. The mixed type of failure was the most common in all groups. Self-etching (G4) and self-adhesive resin (G5) cements, showed similar BS results of immediate bonding in the cementation of GFP compared to conventional resin cements (G1, G2, G3). Key words:Dental Cements, Dentin-Bonding Agents, Post and Core Technique, Dental Bonding.

Effect of intra-radicular cleaning protocols after post-space preparation on marginal adaptation of a luting agent to root dentin.

To evaluate the effect of intra-radicular cleaning protocols after post-space preparation (PSP) on marginal adaptation of a luting agent to root dentin. Eighty bovine incisors were sectioned transversely to obtain 18-mm-long root sections. The roots were prepared with ProTaper instruments and filled using Tagger's hybrid technique. PSP was performed at a length of 14 mm using #3-5 Largo drills. The roots were distributed into eight groups according to the chelating solution used (17% EDTA or 0.2% Chitosan) and the chelating activation/delivery method employed (conventional needle irrigation [CNI], EndoActivator [EA], XP-Endo Finisher [XPF] or passive ultrasonic irrigation [PUI]). The fiber posts were cemented using self-adhesive resin cement, and the roots were sectioned to obtain three discs from each root third. The dentin discs were observed under an optical microscope at ×40 magnification to assess marginal adaptation. The different protocols were compared considering the frequency of the marginal adaptation scores using the Kruskal-Wallis test, followed by the Dwass-Steel-Critchlow-Fligner test (α = 5%). The use of 17% EDTA resulted in better marginal adaptation (P < 0.001). PUI yielded results that were similar to those for EA (P = 0.949) and superior to those for XPF (P = 0.020). The combination of 17% EDTA + PUI provided a greater number of interfaces without marginal gaps (P < 0.001). The cleaning protocol influenced the marginal adaptation of resin cement to root dentin.

Dentinal tubule penetration of sodium hypochlorite in root canals with and without mechanical preparation and different irrigant activation methods.

This study evaluated the dentinal penetration depth of 2.5% sodium hypochlorite (NaOCl) in root canals with and without preparation and different irrigant activation protocols. Sixty-three bovine mandibular incisors were randomly allocated to 6 groups (n = 10): G1, preparation + conventional needle irrigation (CNI); G2, preparation + passive ultrasonic irrigation (PUI); G3, preparation + Odous Clean (OC); G4, no preparation + CNI; G5, no preparation + PUI; G6, no preparation + OC; and CG (negative control; n = 3). Samples were filled with crystal violet for 72 hours. Irrigant activation was performed. Samples were sectioned perpendicularly along the long axis, 3 mm and 7 mm from the apex. Images of the root thirds of each block were captured with a stereomicroscope and analyzed with an image analysis software. One-way analysis of variance, followed by the Tukey post hoc test, and the Student's t-test were used for data analysis, with a significance level of 5%. The NaOCl penetration depth was similar when preparation was performed, regardless of the method of irrigation activation (p > 0.05). In the groups without preparation, G6 showed greater NaOCl penetration depth (p < 0.05). The groups without preparation had a greater NaOCl penetration depth than those with preparation (p = 0.0019). The NaOCl penetration depth was similar in groups with root canal preparation. Without root canal preparation, OC allowed deeper NaOCl penetration. The groups without preparation had greater NaOCl penetration than those undergoing root canal preparation.

A confocal laser scanning microscopic evaluation of nonthermal atmospheric plasma on the dentinal tubule penetration of bioceramic and epoxy resin-based root canal sealers.

Using confocal laser scanning microscopy (CLSM), the current study assessed the impact of nonthermal atmospheric plasma (NTAP) on the dentinal tubule penetration of bioceramic and epoxy resin-based root canal sealers (CLSM). Forty human mandibular premolar teeth with a single root that had just undergone extraction were chosen and biomechanical preparation of root canals was done with ProTaper Gold rotary Nickel-titanium instruments. Samples were divided into four groups (n = 10). Group 1: Bioceramic sealer (BioRoot RCS); Group 2: Epoxy resin-based sealer (AH Plus) without application of NTAP; Group 3: Bioceramic sealer (BioRoot RCS); and Group 4: Epoxy resin-based sealer (AH Plus) with the application of NTAP for 30 s. In Groups 3 and 4, all of the samples underwent obturation with the appropriate sealers following NTAP application. For determination of the sealer's dentinal tubule penetration values, slices with a thickness of 2 mm were taken from the middle third of sample's root and examined using CLSM. The acquired data were statistically analyzed with one-way analysis of variance and the Post hoc Tukey's test. The cutoff for statistical significance was P < 0.05. In comparison to other groups, the maximum sealer penetration values into dentinal tubules were significantly higher in Group 3 for Bioceramic sealer with NTAP application and Group 4 for Epoxy resin-based sealer with NTAP application. NTAP application increased the dentinal tubule penetration of bioceramic and epoxy resin-based sealers in comparison to groups without NTAP application.

Evaluation of the Efficacy of Different Irrigation Systems on the Removal of Root Canal Smear Layer: A Scanning Electron Microscopic Study

Irrigation represents a crucial step in endodontics for bacteria disinfection and smear layer removal. Several irrigation strategies have been proposed, although their effects are controversial. This study aims to assess the comparison of four different irrigation systems on the smear layer removal utilizing scanning electron microscopy (SEM). Forty sound monoradicular teeth were collected and casually allocated into four groups (n = 10): Group A, conventional irrigation; Group B, IrriFlex irrigation; Group C, ultrasonic irrigation system; Group D, apical negative pressure irrigation. After chemo-mechanical preparation and longitudinal root separation, the three root thirds were analyzed by SEM. Micrographs were carried out at ×2000 to analyze the smear layer residual in each third of the root canal. Statistically significant differences were found between Group A and Group D (p &lt; 0.05). Groups B and C showed satisfactory results in the coronal and middle thirds, while Group D was the only system that achieved satisfactory results in the apical third. However, the complete smear layer removal in the root canal was never achieved with any of the four systems tested. In conclusion, among the four tested irrigation systems, the greatest efficacy on smear layer removal was reached by Group D.

&lt;strong&gt;The effect of oligosaccharide chitosan irrigating agent on penetration of two type endodontic sealers into the dentinal tubules: a confocal laser scanning microscopy study&lt;/strong&gt;

ABSTRACTIntroduction: Irrigation during root canal treatment is one of the important factors that play a role in determining the quality of sealer penetration into the dentinal tubules, especially in the apical third of the tooth root. This is inseparable from the selection of the used irrigation agent. Currently, oligosaccharide chitosan has been developed which is easier to manipulate as an alternative irrigation agent. This study aimed to analyze the effect of the chitosan oligosaccharide irrigating agent on the penetration of two types of endodontic sealers into the dentinal tubules. Methods: This study used 60 mandibular premolars which were randomly divided into 3 groups (n=3). Group 1 was irrigated with 2% chitosan oligosaccharides; Group 2 with a combination of 2.5% NaOCl and 0.2% chitosan nanoparticles; and group 3 was irrigated with a combination of 2.5% NaOCl and 17% EDTA. At the time of obturation, each group was divided into two groups, for sealer treatment using CeraSeal Bioceramic and AH Plus sealer. The sealer’s penetration depth was measured using a confocal laser scanning microscope. Results: The highest mean on the penetration depth of the sealer was seen in the irrigation group using chitosan oligosaccharide solution with CeraSeal bioceramic sealer (2575,151 AU) (p&gt;0.05). Conclusion: There is an effect of 2% oligosaccharide chitosan solution on sealer penetration into dentinal tubules. CeraSeal bioceramic sealer showed better penetration than AH Plus sealer.Keywords: oligosaccharide chitosan; ceraseal bioceramic sealer; AH plus sealer; confocal laser scanning microscope

A Modern View of Human Tooth Roots Apical Morphology (Literary Data Analysis)

Many anatomical landmarks and their corresponding terminology can be found in the scientific and educational literature that characterize the apical third of tooth roots. They are often used in the subsequent description of the clinical situation to carry out treatment procedures and predict the outcome of the disease. The morphology of the apical third of the root canals has always been the subject of research. The use of electron-scanning and stereo microscopes in the study of the apical third have become a new challenge for both researchers and practicing dentists. This method of research allows not only to determine the location, shape, size and quantity of the anatomical hole, but also to characterize the morphology of the most hidden details of its lumen accurately. A study of the literature revealed that a number of studies have been devoted to the study of Intradont architectonics. At different times, apical thirds of different groups of teeth were examined under a scanning and stereo microscope in various countries. Our literature analysis revealed many interesting and mutually exclusive facts. Noteworthy is different (heterogeneous) terminology of the morphological elements of the apical part of the root, which complicates the theoretical understanding of the issue and its application in clinical practice. The abovementioned demonstrates not only the importance of conducting such research in Georgia and its need. However, studying the apical thirds of the tooth roots that will be the target of our future.

A Modern View of Human Tooth Roots Apical Morphology (Literary Data Analysis)

Many anatomical landmarks and their corresponding terminology can be found in the scientific and educational literature that characterize the apical third of tooth roots. They are often used in the subsequent description of the clinical situation to carry out treatment procedures and predict the outcome of the disease. The morphology of the apical third of the root canals has always been the subject of research. The use of electron-scanning and stereo microscopes in the study of the apical third have become a new challenge for both researchers and practicing dentists. This method of research allows not only to determine the location, shape, size and quantity of the anatomical hole, but also to characterize the morphology of the most hidden details of its lumen accurately. A study of the literature revealed that a number of studies have been devoted to the study of Intradont architectonics. At different times, apical thirds of different groups of teeth were examined under a scanning and stereo microscope in various countries. Our literature analysis revealed many interesting and mutually exclusive facts. Noteworthy is different (heterogeneous) terminology of the morphological elements of the apical part of the root, which complicates the theoretical understanding of the issue and its application in clinical practice. The abovementioned demonstrates not only the importance of conducting such research in Georgia and its need. However, studying the apical thirds of the tooth roots that will be the target of our future.