Pre-eruptive intracoronal resorption of permanent dentition: A new classification and a multidisciplinary study.

The aims of this study were to develop a new classification for pre-eruptive intracoronal resorption(PIR) with different resorption areas and sizes and to compare the new classification scores among observers from different specialities and professional experience. The PIR was evaluated according to the new classification by two dentomaxillofacial radiologists and two endodontists. Information regarding the patient's age, gender, systemic diseases, the number of PIR, the affected tooth area and the size of the PIR was recorded. The new classification system showed that PIR six and seven defects were the most detected. Regarding jaw regions, the highest reliability was seen in the maxillary central teeth between observers I and IV, and maxillary premolar-molar teeth between observers II and III. This study revealed that PIR can be found in both root and crown dentine. Professional experience and specialty and awareness of the PIR defect may affect the diagnosis.

The Effect of Different Final Irrigation Regimens on the Dentinal Tubule Penetration of Three Different Root Canal Sealers: A Confocal Laser Scanning Microscopy Study In Vitro.

This study evaluated the effects of different final irrigation regimens on the dentin tubule penetration of three different root canal sealers using confocal laser scanning microscopy (CLSM). A total of 160 single-rooted extracted mandibular premolar teeth were divided into five groups (n = 32 each) according to the solution used in the final rinse protocol, as follows: 17% ethylenediaminetetraacetic acid (EDTA) (group 1), 17% EDTA and 2% chlorhexidine gluconate (CHX) (group 2), 7% maleic acid (MA) (group 3), 7% MA and 2% CHX (group 4), and 5.25% NaOCl (group 5). Two roots from each group were examined under scanning electron microscopy (SEM) to visualize smear layer removal. Experimental groups were then split randomly into three subgroups (n = 10) and obturated using a cold lateral condensation technique with 0.1% rhodamine B-labelled sealers [either AH Plus (group A), EndoREZ (group E), or Tech BioSealer Endo (group T)] and gutta-percha. Specimens were sectioned and observed by CLSM to evaluate the percentage and maximum depth of sealer penetration at the apical, middle, and coronal levels. Statistical comparison was performed on grouped (apical, middle, and coronal segments) and ungrouped data using two-way ANOVA with Bonferroni post hoc test (p < 0.01). AH Plus showed the greatest tubule penetration while Tech BioSealer Endo showed the least. Resin-based sealers displayed deeper and more consistent penetration. CHX irrigation positively influenced sealer tubule penetration.

Comparison of Fracture Resistance of Endodontically Treated Teeth Restored with FiberSite Postsystem and Glass Fiber, Combined with Different Root Canal Sealers.

This study is aimed at evaluating the effects of FiberSite and glass fiber postsystems on the fracture resistance of endodontically restored teeth, when combined with various root canal sealers. Forty human mandibular premolar teeth, each having a single root with anatomically comparable dimension and length, were selected. The teeth in each experimental group (n = 10) were instrumented, obturated, and restored with the following procedures: in group 1, AH Plus root canal sealer and a glass fiber post with a composite core; in group 2, AH Plus root canal sealer and a FiberSite postsystem; in group 3, Sure-Seal Root canal sealer and a glass fiber post with a composite core; and in group 4, Sure-Seal Root canal sealer and a FiberSite postsystem. The specimens were placed on a universal test machine. The fracture resistance of all specimens was tested using generic test equipment, and the value of the force in newton (N) during fracture was measured for each root. A statistical analysis was conducted through the Kruskal-Wallis test as well as the post hoc test. The tests showed a significant difference between groups 2 and 3, with group 3 producing load values that were significantly higher than group 2. In contrast, no significant differences were found to exist between the other groups. Regardless of postsystems, groups 3 and 4 showed higher mean fracture values (but no statistically significant differences) than groups 1 and 2.

Comparative analysis of different periapical index systems used in cone-beam computed tomography.

This study aimed to compare the three index systems designed for cone-beam computed tomography (CBCT) in terms of intra- and inter-observer agreement. 117 root-filled teeth with or without periapical radiolucency from 77 of already existing CBCT images were chosen randomly. Two observers evaluated the periapical status of the selected teeth and graded the scores twice using CBCT periapical index (CBCTPAI), endodontic radiolucency index (ERI) and complex periapical index (COPI) part of the periapical and endodontic status scale (PESS), respectively. The researchers' self-agreement kappa values ranged from substantial to almost perfect. A moderate inter-observer agreement was present for the COPI and ERI, whereas a fair agreement was present for CBCTPAI. The researchers' ICC for the inter-observer reliability of CBCTPAI, ERI and COPI was 0.75, 0.77 and 0.80, respectively. COPI had the highest self-agreement and inter-observer reliability. ERI showed the highest intra-observer variation, whereas CBCTPAI showed the highest inter-observer variation.

Comparison of three adhesive systems in class II composite restorations in endodontically treated teeth: Influence of Er:YAG laser conditioning and gingival margin levels on microleakage.

BACKGROUND: Dental surface conditioning by Er:YAG laser is currently being investigated, as not all of the mechanisms and effects of this technique have been clearly studied. Thus, the aim of the present study was to assess the cervical microleakage of Class II resin composite restorations in endodontically treated teeth following either the respective conventional conditioning or additional Er:YAG laser conditioning, in association with varied adhesives. MATERIAL AND METHODS: Standardized mesial-occlusal-distal cavities (two gingival walls positioned in dentin and enamel, respectively) were created in 60 extracted human premolar teeth. Following the completion of the endodontic therapy, the teeth were grouped into six categories based on conditioning modality and adhesive strategy as follows: group 1-37% phosphoric acid/Adper Single Bond 2 (ASB2); group 2-Er:YAG laser/37% phosphoric acid/ASB2; group 3-Clearfil SE Bond (CSE); group 4-Er:YAG laser/CSE; group 5-Adper Easy One (AEO); and group 6-Er:YAG laser/AEO. Specimens were submitted to thermocycling and dye penetration, followed by longitudinal sectioning. The dye penetration was evaluated using a stereomicroscope. One specimen from each group was assessed under a scanning electron microscope for adhesive interface analysis. RESULTS: No significant differences were found between the conditioning modalities, nor between the adhesive systems at both margins. Groups 1 and 2 showed a lower degree of microleakage in the enamel vs. dentin (p = 0.002). Group 2 showed a significantly lower incidence of microleakage in enamel vs. dentin (p = 0.005). CONCLUSIONS: CSE and AEO were comparable with that of ASB2 regarding sealing ability. Additional Er:YAG laser conditioning may be beneficial before ASB2 application in enamel. Key words:Endodontically treated teeth, etch-and-rinse adhesive, Er:YAG laser, gingival level, sealing ability, self-etch adhesive.

A Comparison of Er:YAG Laser with Photon-Initiated Photoacoustic Streaming, Nd:YAG Laser, and Conventional Irrigation on the Eradication of Root Dentinal Tubule Infection by Enterococcus faecalis Biofilms: A Scanning Electron Microscopy Study.

This study evaluated the antimicrobial efficacy of Er:YAG laser activation with photon-initiated photoacoustic streaming (PIPS), Nd:YAG laser disinfection, and conventional irrigation on Enterococcus faecalis biofilms using scanning electron microscopy (SEM). Biofilms were grown on 110 root halves and divided into the following: Groups 1 and 2 (saline and 1% NaOCl with apical position of PIPS, resp.), Groups 3 and 4 (saline and 1% NaOCl with coronal position of PIPS, resp.), Groups 5 and 6 (Nd:YAG laser after saline and 1% NaOCl irrigation, resp.) and Groups 7, 8, and 9 (conventional irrigation with 1% NaOCl, 6% NaOCl, and saline, resp.). SEM images of the apical, middle, and coronal levels were examined using a scoring system. Score differences between Groups 1 and 2 were insignificant at all levels in the remaining biofilm. Group 4 had significantly greater bacterial elimination than Group 3 at all levels. Differences in Nd:YAG laser irradiation between Groups 5 and 6 were insignificant. Groups 7 and 8 were insignificantly different, except at the middle level. Saline group had a higher percentage of biofilms than the others. In this study, PIPS activation with NaOCl eliminates more E. faecalis biofilms in all root canals regardless of the position of the fiber tip.

Change in Periapical Lesion and Adjacent Mucosal Thickening Dimensions One Year after Endodontic Treatment: Volumetric Cone-beam Computed Tomography Assessment.

INTRODUCTION: Changes in periapical lesion dimensions along with mucosal thickening after endodontic treatment have not been studied yet. Therefore, the objectives of this study were (1) to obtain linear and volumetric measurements of lesion dimensions in maxillary first molars with periapical pathology and (2) to measure maxillary sinus mucosal thickening in the vicinity of periapical lesions before and 1 year after endodontic treatment by using cone-beam computed tomography (CBCT). METHODS: Twenty-one maxillary first molar teeth of 21 patients (14 female and 7 male) with periapical lesion that had local mucosal thickening in the vicinity of the periapical lesion were endodontically treated. A total of 21 maxillary first molar roots (8 mesiobuccal roots, 6 distobuccal roots, and 7 palatal roots), each one from different patients, was included. Pretreatment and 1-year post-treatment CBCT images of each tooth were obtained by using Kodak CS 9300 3D CBCT unit. Width, height, surface area, and volume measurements of periapical lesions and mucosal thickening of the maxillary sinus mucosa in the vicinity of the periapical lesion were measured before and 1 year after endodontic treatment. General linear model (analysis of variance) was used for the comparisons between measurements, and significance was set at P < .05. Regression analysis was also used to test the correlation between different measurements. RESULTS: We found statistically significant differences between mean pretreatment and mean post-treatment measurements conducted by using CBCT images (width, P = .002; height, P < .001; maximum mucosal thickening, P < .001; medium mucosal thickening, P < .001; minimum mucosal thickening, P < .001; surface area, P = .032; and volume, P = .034). Considering gender, age, and root-type variables, no significant differences were found for all the measurements conducted (P > .05). There were 36%, 41%, 53%, 54%, 53%, 73%, and 75% mean reductions in lesion width, lesion height, maximum sinus mucosal thickness, medium sinus mucosal thickness, minimum sinus mucosal thickness, lesion surface area, and lesion volume, respectively, before and 1 year after endodontic treatment. Regression analysis of pretreatment lesion volume versus percentage of post-treatment lesion volume change revealed a low regression coefficient (R2 = 16.7%, P > .05), showing a weak linear relationship. CONCLUSIONS: CBCT assessment of changes in periapical lesion and mucosal thickening dimensions may reveal useful information regarding endodontic treatment success.

Benign paroxysmal positional vertigo after nonotologic surgery: case series.

Benign paroxysmal positional vertigo is one of the most common types of vertigo caused by peripheral vestibular dysfunction. Although head trauma, migraine, long-term bed rest, Ménière disease, viral labyrinthitis, and upper respiratory tract infections are believed to be predisposing factors, most cases of benign paroxysmal positional vertigo are idiopathic. Ear surgery is another cause, but after non-otologic surgery, attacks of benign paroxysmal positional vertigo are rare. We describe three cases of benign paroxysmal positional vertigo attacks after non-otologic surgery (one patient after a nasal septoplasty and two patients after dental endodontic treatment) and discuss the pathophysiological mechanism of benign paroxysmal positional vertigo seen after non-otologic surgery, its diagnosis and treatment.

Resistance to fracture of dental roots obturated with different materials.

The aim of this study was to compare the vertical fracture resistance of roots obturated with different root canal filling materials and sealers. Crowns of 55 extracted mandibular premolar teeth were removed to provide root lengths of 13 mm. Five roots were saved as negative control group (canals unprepared and unfilled). Fifty root canals were instrumented and then five roots were saved as positive control group (canals prepared but unfilled). The remaining 45 roots were randomly divided into three experimental groups (n = 15 root/group) and obturated with the following procedures: in group 1, glass ionomer-based sealer and cone (ActiV GP obturation system); in group 2, bioceramic sealer and cone (EndoSequence BC obturation system); and in group 3, roots were filled with bioceramic sealer and cone (Smartpaste bio obturation system). All specimens were tested in a universal testing machine for measuring fracture resistance. For each root, the force at the time of fracture was recorded in Newtons. The statistical analysis was performed by using Kruskal-Wallis and post hoc test. There were no significant differences between the three experimental groups. The fracture values of three experimental and negative control groups were significantly higher than the positive control group. Within the limitations of this study, all materials increased the fracture resistance of instrumented roots.

The effect of temperature and contact time of sodium hypochlorite on human roots infected with Enterococcus faecalis and Candida albicans.

The aim of this study was to evaluate the effectiveness of 2.5 % NaOCl at different temperature and time intervals on Enterococcus faecalis and Candida albicans-infected human roots. A total of 112 root cylinders prepared from extracted single-rooted humans were infected by E. faecalis (Group A, n = 56) or C. albicans (Group B, n = 56); 3 root cylinders served as negative controls. Both groups were further divided into 6 subgroups according to three contact times (30 s, 1 min, 5 min) with NaOCl at two different temperatures (25 or 37 °C). Microorganism growth was controlled at the 24th and 48th hours. Statistical analysis was performed using the Chi-square test. While NaOCl at 25 °C for 5 min was the most effective irrigation regimen to eliminate E. faecalis (p < 0.001), NaOCl at 37 °C for 5 min exhibited significantly superior antifungal properties (p < 0.05). At the same contact times, difference in the temperature of NaOCl did not affect the growth of either E. faecalis or C. albicans. As a result, the irrigation time of NaOCl was more effective than the temperature to eliminate E. faecalis, while pre-heating of NaOCl to 37 °C increased its effectiveness on C. albicans at 5 min contact time.

Antimicrobial efficacy of octenidine hydrochloride, MTAD and chlorhexidine gluconate mixed with calcium hydroxide.

OBJECTIVE: The aim of this in vitro study was to investigate whether mixing with calcium hydroxide [Ca(OH)2] affects the antimicrobial action of Octenidine hydrochloride (Octenisept), MTAD and chlorhexidine against Enterococcus faecalis and Candida albicans. MATERIALS AND METHODS: Freshly grown cultures of Enterococcus faecalis, Candida albicans and a mixture of both strains were incubated in agar plates containing brain-heart infusion broth (BHIB). Zones of inhibition were measured at 24 and 48 hours. Statistical analysis was performed using Mann-Whitney U test and Kruskal-Wallis one-way analysis of variance (ANOVA, both p=0.05). RESULTS: Mixing with Ca(OH)2 significantly increased the antibacterial effect of Octenisept (p<0.05), but did not alter its antifungal activity. Only chlorhexidine showed more antibacterial and antifungal efficiency compared to its Ca(OH)2-mixed version (both p<0.05). Mixing with Ca(OH)2 decreased the antibacterial efficacy of MTAD, but increased its antifungal effect (both p<0.05). CONCLUSION: These results demonstrate the differential effects of Ca(OH)2 addition on the antimicrobial action of the tested endodontic medicaments in vitro. Ca(OH)2 was as effective as its combination with all of the tested medicaments.

Effect of bleaching agents on sealing properties of different intraorifice barriers and root filling materials.

OBJECTIVE: To evaluate the effect of intracoronal bleaching agents on the sealing properties of different intraorifice barriers and root filling materials. STUDY DESIGN: The root canals of extracted human premolars (n=180) were prepared by using System GT rotary files and filled with either gutta-percha+AH Plus or Resilon+Epiphany sealer. In both groups, the coronal 3mm of root filling was removed and replaced with one of the following materials applied as intraorifice barriers (n=30/group): 1. ProProot-MTA; 2. Conventional Glass ionomer cement; and 3. Hybrid resin composite. In each subgroup, intracoronal bleaching was performed using either sodium perborate with distilled water or 35% hydrogen peroxide gel for 3 weeks. The leakage of specimens was measured using fluid-filtration and dye penetration tests. The data were analyzed statistically with One-way ANOVA, Repeated Measures t-test and Independent Samples t-test (p=0.05). RESULTS: The fluid conductance values of the test groups were not influenced by the type of the bleaching agent, the intraorifice barrier, or the root filling material (all p>0.05). However, the extent of dye leakage was significantly affected by the type of intraorifice barrier material (p<0.05), which showed the following statistical ranking: glass ionomer cement > resin composite > ProRoot-MTA (p<0.05). CONCLUSIONS: The effect of 35% hydrogen peroxide gel or sodium perborate/distilled water on the sealing properties of tested intraorifice barriers and root filling materials varied conforming leakage assessment. These properties were not affected by using fluid filtration test, while the glass ionomer barrier showed the greatest amount of dye leakage in both gutta-percha and Resilon root-filled teeth.

Effect of sodium ascorbate on bond strength of different adhesive systems to NaOCl-treated dentin.

The aim of this study was to evaluate the effects of sodium ascorbate on bond strength of different adhesive systems to NaOCl-treated dentin. Eighty extracted molar teeth were used in the study. The buccal enamel surfaces were removed to obtain a flat dentin surface. The teeth were mounted in self-curing resin and dentin surfaces were irrigated with NaOCl for 10 min. Half of the specimens were treated with sodium ascorbate for 10 min. The teeth were randomly assigned to four subgroups according to the adhesive systems used (Clearfil SE Bond, Clearfil Tri-S Bond, Adper Prompt-L-Pop, Adper Single Bond 2). Bond strengths were determined with a Universal Testing Machine, at a crosshead speed of 0.5 mm/min. Data were statistically analysed using anova at a significance level of 0.05. Two-way ANOVA revealed that the effect of sodium ascorbate application on bond strength of adhesive systems to NaOCl-treated dentin was statistically significant (P < 0.05). The bond strength results were significantly influenced by the application of sodium ascorbate (P < 0.05) and there was a significant difference between the adhesive systems (P < 0.05). Although statistically significant differences were not demonstrated in all adhesive resin groups, sodium ascorbate application after NaOCl treatment improved the bond strength values.

Could digital imaging be an alternative for digital colorimeters?

This study evaluated the colour parameters of composite and ceramic shade guides determined using a colorimeter and digital imaging method with illuminants at different colour temperatures. Two different resin composite shade guides, namely Charisma (Heraeus Kulzer) and Premise (Kerr Corporation), and two different ceramic shade guides, Vita Lumin Vacuum (VITA Zahnfabrik) and Noritake (Noritake Co.), were evaluated at three different colour temperatures (2,700 K, 2,700-6,500 K, and 6500 K) of illuminants. Ten shade tabs were selected (A1, A2, A3, A3,5, A4, B1, B2, B3, C2 and C3) from each shade guide. CIE Lab values were obtained using digital imaging and a colorimeter (ShadeEye NCC Dental Chroma Meter, Shofu Inc.). The data were analysed using two-way ANOVA, and Pearson's correlation. While mean L* values of both composite and ceramic shade guides were not affected from the colour temperature, L* values obtained with the colorimeter showed significantly lower values than those of the digital imaging (p < 0.01). At combined 2,700-6500 K colour temperature, the means of a* values obtained from colorimeter and digital imaging did not show significant differences (p > 0.05). For both composite and ceramic shade guides, L* and b* values obtained from colorimeter and digital imaging method presented a high level of correlation. High-level correlations were also acquired for a* values in all shade guides except for the Charisma composite shade guide. Digital imaging method could be an alternative for the colorimeters unless the proper object-camera distance, digital camera settings and suitable illumination conditions could be supplied. However, variations in shade guides, especially for composites, may affect the correlation.

Effects of different ceramic and composite materials on stress distribution in inlay and onlay cavities: 3-D finite element analysis.

To reduce loss of tooth tissue and to improve esthetic results, inlay and onlay restorations are good treatment choices for extensive cavities in posterior teeth. The aim of this paper was to evaluate, by means of three-dimensional finite element analysis, the effects of restorative material and cavity design on stress distribution in the tooth structures and restorative materials. Two different nanofilled composites and two different all-ceramic materials were used in this study. A permanent molar tooth was modeled with enamel and dentin structures. 3-D inlay and onlay cavity designs were created. Von Mises, compressive, and tensile stresses on the restorative materials, core materials, enamel, and dentin were evaluated separately. On the effect of restorative material, results showed that in the case of materials with low elastic moduli, more stress was transferred to the tooth structures. Therefore, compared to the nanofilled composites, the all-ceramic inlay and onlay materials tested transferred less stress to the tooth structures. On the effect of cavity design, the onlay design was more efficacious in protecting the tooth structures than the inlay design.

Effect of LED curing on marginal integrity of an ormocer-based sealant.

PURPOSE: The purpose of this study was to investigate the microleakage of a light cured, ormocer-based fissure sealant when photopolymerized with 2 different light emitting diode (LED) curing units and a conventional quartz-tungsten halogen (QTH) light-curing unit. METHODS: Thirty freshly extracted, unerupted human third molars from 9 adolescent were randomly assigned into 3 groups (N=10/group). Pits and fissures were acid etched for 30 seconds, rinsed for 15 seconds with an air-water spray, and air-dried. An ormocer-based fissure sealant material (Admira Seal) was applied to all fissures. In group 1, the sealant was photopolymerized with a Smart Light LED curing unit (Dentsply) for 10 seconds. Another LED curing unit (Elipar II) and a conventional QTH curing unit (Hilux) were used in groups 2 and 3 for 10 and 30 seconds, respectively. Specimens were immersed in 0.5% basic fuchsin for 24 hours, sectioned and examined under a stereomicroscope, and scored for marginal microleakage. RESULTS: Statistical analysis of microleakage scores revealed no significant difference among the groups tested (P>.05, Kruskal-Wallis test). CONCLUSION: The tested LED curing units may provide reduction in total application time without comprising marginal integrity of the ormocer-based sealant.

Time-dependent conversion of a methacrylate-based sealer polymerized with different light-curing units.

The purpose of this study was to investigate the degree of conversion of a methacrylate-based sealer (Epiphany; Pentron Clinical Technologies, Wallingford, CT) with regard to the method of photoactivation, distance from the light-curing unit (LCU), and post-curing time. Freshly mixed Epiphany sealer was dispensed into half-pipe-shaped silicone moulds (n = 48), after which the specimens were photoactivated with one of the following LCUs from the coronal aspect: (1) quartz tungsten halogen/40 seconds and (2) light-emitting diode/20 seconds. In each specimen, the degree of conversion was measured at three different locations (coronal, middle, and apical) using Fourier transform infrared spectroscopy before and after photoactivation. The amount of conversion was approximately 50% after photoactivation and improved by approximately 10% after 15 days. Conversion of Epiphany was not affected by the type of LCU (p > 0.001) or the distance from the LCU (p > 0.001) but showed a significant increase within time (p < 0.001). These results indicate incomplete polymerization of Epiphany, despite a post-curing time of as long as 2 weeks in vitro.

Treatment of horizontal root-fractured maxillary incisors--a case report.

Traumatic dental injuries often occur to the teeth and their supporting tissues and they are the main reasons for emergency visit to a dental clinic. Management of a fracture depends on its position and the extent of root involvement. Horizontal root fractures are not seen frequently and the treatment consists of reduction and long-term rigid fixation of the coronal segment. The present case demonstrates the successful management of two horizontally fractured maxillary central incisors with a follow-up period of 9 months.

Assessment of possible risk indicators for apical periodontitis in root-filled teeth in an adult Turkish population.

OBJECTIVE: The objective of this study was to determine possible independent risk indicators of apical periodontitis (AP) in root-filled teeth in an adult Turkish population. STUDY DESIGN: This study included subjects older than 15 years who had 1 or more root-filled teeth examined at the Baskent University Faculty of Dentistry. A total of 812 root-filled teeth were evaluated in 425 individuals. AP was the dependent variable and age, gender, length and density of root fillings, presence of periodontal problems, posts, localization of tooth, and tooth type were identified as independent variables. Generalized Estimating Equation (GEE) models were used in statistical analysis. RESULTS: AP was detected on 148 teeth (18.2%) in 812 root-filled teeth. According to multiple GEE model, males were more likely to have AP than females. Of the dental variables, length of root fillings, periodontal problems and tooth type were significantly associated with AP. CONCLUSIONS: The present study indicates that to be male and dental variables including length of root fillings, periodontal problems, and molar teeth were significantly associated with AP.