Comparison of the pull-out bond strength of endodontically treated anterior teeth with monolithic zirconia endocrown and post-and-core crown restorations.

PURPOSE: The purpose of this study was to assess the pull-out bond strength (PBS) of endodontically treated anterior teeth that had been restored with monolithic zirconia endocrowns using different extension depths (EDs) and post-and-core crowns after chewing simulation. METHODS: Thirty-six maxillary central teeth were used (n = 12). Group I: Glass fiber post-and-core crown, Group II: Endocrown with 3-mm EDs, Group III: Endocrown with 5-mm EDs. Restorations were fabricated from monolithic zirconia blocks using a CAM (computer-aided manufacturing) device. For cementation, conventional resin luting agent (Multilink N) was used. All samples were aged with a chewing simulator and PBS tests were conducted at a speed of 1 mm/min using an electromechanical servo universal testing machine. The values were recorded in MPa by dividing the failure load by the bonding area. One-way ANOVA and the post-hoc Tukey test were used for statistical analysis (P = 0.05). RESULTS: Group III demonstrated significantly greater PBS values than Groups I and II (P = 0.001). No significant difference was found between Groups I and II (P = 0.072). CONCLUSION: Increasing the ED of an endocrown influences the PBS of endodontically treated anterior teeth restored with monolithic zirconia endocrowns.

Effect of surface treatment, ferrule height, and luting agent type on pull-out bond strength of monolithic zirconia endocrowns.

PURPOSE: To evaluate the effect of different surface treatments, ferrule heights, and luting agents on the pull-out bond strength (PBS) of computer-aided design/computer-aided manufacturing (CAD-CAM) monolithic endocrowns. METHODS: After endodontic treatment and preparation for two endocrown designs (ferrule height 0 mm or 2 mm), CAD-CAM monolithic zirconia endocrowns were fabricated for 80 mandibular molars. Each endocrown design group was then divided on the basis of surface treatment into two groups: half were air-abraded and half were air-abraded/laser-irradiated. Then, all treated groups were further divided into two subgroups (n = 10) and cemented to teeth with either a 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing resin luting agent (Panavia SA) or a combination of MDP-containing primer and MDP-free resin luting agent (Monobond Plus/Multilink Automix). PBS was measured with a universal test machine after simulated chewing and thermocycling. Three-way ANOVA and the post-hoc Bonferroni test were used for statistical analysis. RESULTS: PBS was significantly associated with type of surface treatment, type of luting agent, and ferrule height. Air-abraded/laser-irradiated endocrowns with a 2-mm ferrule that were cemented with Monobond Plus/Multilink Automix had the highest PBS (P < 0.05). CONCLUSION: Surface treatment with air abrasion/laser irradiation, presence of a ferrule, and priming with an MDP-containing primer increased the PBS of monolithic zirconia endocrowns.

Assessment of technical quality of 9562 endodontic cases treated by undergraduate students and endodontics specialists / Avaliação da qualidade técnica de 9562 casos endodônticos tratados por estudantes de graduação e especialistas em endodontia

Objective: The aim of the study was to assessment of technical quality of 9562 endodontic cases treated by heterogeneous groups with different clinical experience. Material and methods: This retrospective study reviewed the dental records of 8590 patients (9562 endodontic cases and 13203 root canals including 3340 retreatment root canals) treated by fourth-year undergraduates, fifth-year undergraduates, endodontic program students, and endodontic specialists between December 2017 and December 2018 at the Department of Endodontics of Necmettin Erbakan University Faculty of Dentistry in Konya. The length, density, and taper of root fillings, the acceptable technical quality of the root filling criteria, and the presence of procedural errors, were recorded. Chi-square tests with a significance level at p=0.05 were used for statistical analysis. Results: Acceptable root fillings were found in 71.5% of endodontic cases. Clinical experience showed statistical differences in the root filling quality among fourth-year undergraduates, fifth-year undergraduates, endodontic program students, and specialists (52, 63.1, 77.9 and 86.5% respectively). Fractured instruments and missed canals were noted in 9.8% and 0.57% of cases treated by endodontic program students significantly more than the other clinical experiences. No statistical differences were found among the clinical experiences in other procedural errors. No statistically significant differences were found between age range and gender in additional root canals. Statistically significant differences were observed between the number of root canal retreatments in terms of age range and gender. Conclusions: Clinical experience affects the technical quality of root canal treatments. Fractured instruments and missed canals, especially by endodontic program students, should be given more attention. (AU)

Objetivo: O objetivo do estudo foi avaliar a qualidade técnica de 9562 casos endodônticos tratados por grupos heterogêneos com diferentes experiências clínicas. Material e métodos:Este estudo retrospectivo revisou os registros dentários de 8590 pacientes (9562 casos endodônticos e 13203 canais radiculares, incluindo 3340 canais radiculares de retratamento) tratados por graduandos do quarto ano, graduandos do quinto ano, estudantes do programa endodôntico e especialistas em endodontia, entre dezembro de 2017 e dezembro de 2018 no Departamento de Endodontia da Faculdade de Odontologia da Universidade Necmettin Erbakan em Konya. O comprimento, a densidade e a conicidade dos preenchimentos das raízes, a qualidade técnica aceitável dos critérios de preenchimento das raízes e a presença de erros processuais foram registrados. Os testes de qui-quadrado com nível de significância de p = 0,05 foram utilizados para análise estatística. Resultados:O preenchimento radicular aceitável foi encontrado em 71,5% dos casos endodônticos. A experiência clínica mostrou diferenças estatísticas na qualidade do preenchimento das raízes entre os alunos do quarto ano, do quinto ano, estudantes do programa endodôntico e especialistas (52, 63,1, 77,9 e 86,5%, respectivamente). Instrumentos fraturados e canais perdidos foram observados em 9,8% e 0,57% dos casos tratados pelos estudantes do programa endodôntico significativamente mais do que nas outras experiências clínicas. Não foram encontradas diferenças estatísticas entre as experiências clínicas em outros erros processuais. Não foram encontradas diferenças estatisticamente significantes entre faixa etária e sexo em canais radiculares adicionais. Foram observadas diferenças estatisticamente significantes entre o número de retratamentos do canal radicular em termos de faixa etária e sexo. Conclusões: A experiência clínica afeta a qualidade técnica dos tratamentos do canal radicular. Instrumentos fraturados e canais perdidos, especialmente por estudantes do programa endodôntico, devem receber mais atenção (AU)

Proton Nuclear Magnetic Resonance Spectroscopy Analysis of Mixtures of Chlorhexidine with Different Oxidizing Agents Activated by Photon-Induced Photoacoustic Streaming for Root Canal Irrigation.

Objective: The aim of this in vitro study was to investigate the possible interactions between photon-induced photoacoustic streaming (PIPS™)-activated oxidizing agents and 2% chlorhexidine digluconate. Background data: There is no information about the safety of laser-activated oxidizing agents in combination usage with chlorhexidine gluconate. Materials and methods: Groups were designed as follows G1: 98% para-chloroaniline (PCA); G2: 2% chlorhexidine (CHX); G3: 5.25% sodium hypochlorite (NaOCl) +2% CHX; G4: 5.25% NaOCl (30 sec PIPS activated) +2% CHX; G5: 5.25% NaOCl (60 sec PIPS activated) +2% CHX; G6: 3.5% chlorine dioxide (ClO2) + 2% CHX; G7: 3.5% (ClO2) (30 sec PIPS activated) +2% CHX; G8: 3.5% (ClO2) (60 sec PIPS activated) +2% CHX. The laser-irrigation protocol was performed with an erbium:yttrium-aluminum-garnet laser with a wavelength of 2940 nm equipped with a 140 mm long endodontic fiber tip (PIPS) using 10 mJ at 15 Hz (0.15 W), per pulse operating outputs. Groups were analyzed with proton nuclear magnetic resonance spectroscopy, using PCA as an internal standard. Results: No free PCA was formed in any groups of mixtures or after PIPS activation. Conclusions: Mixing of 3.5% ClO2 and 2% CHX does not form bulky precipitates, unlike the mixture NaOCl + CHX. PIPS activation does not cause changes in reactions of oxidizing agents.

Comparison of cone-beam computed tomography and panoramic radiography in the evaluation of maxillary sinus pathology related to maxillary posterior teeth: Do apical lesions increase the risk of maxillary sinus pathology?

PURPOSE: The aims of this study were first, to compare panoramic radiography with cone-beam computed tomography (CBCT) for evaluating topographic relationships, such as the classification of maxillary posterior teeth and their distance to the maxillary sinus floor; and second, to determine the relationship between maxillary sinus pathology and the presence of apical lesions. MATERIALS AND METHODS: In total, 285 paired CBCT and panoramic radiography records of patients (570 maxillary sinuses) were retrospectively analyzed. Both imaging modalities were used to determine the topographic relationship of the maxillary posterior teeth to the sinus floor. Mucosal thickening >2 mm was considered a pathological state. Data were analyzed using the chi-square, Wilcoxon, and Mann-Whitney U tests. Odds ratios (ORs) and confidence intervals (CIs) were calculated. RESULTS: The closest vertical distance measurements made between posterior maxillary teeth roots and the maxillary sinus on panoramic radiography and CBCT scans showed statistically significant differences from each other (P<0.05). Compared to panoramic radiography, CBCT showed higher mean values for the distance between the maxillary sinus floor and maxillary posterior teeth roots. The CBCT images showed that at least 1 apical lesion adjacent to the right maxillary sinus increased the risk of maxillary sinus pathology by 2.37 times (OR, 2.37; 95% CI, 1.58-3.55, P<0.05). CONCLUSION: Panoramic radiography might lead to unreliable diagnoses when evaluating the distance between the sinus floor and posterior roots of the maxillary teeth. Periapical lesions anatomically associated with maxillary sinuses were a risk factor for sinus mucosal thickening.

Does the Photon-Induced Photoacoustic Streaming Activation of Irrigation Solutions Alter the Dentin Microhardness?

Objective: The aim of this in vitro study was to evaluate the efficacy of photon-induced photoacoustic streaming (PIPS) activation of sodium hypochlorite (NaOCl), chlorhexidine (CHX) or ethylenediaminetetraacetic acid (EDTA) on the dentin microhardness and to assess the compositional changes of root dentin. Background data: It is still unclear whether PIPS activation of irrigants alters the dentin microhardness and mineral content of dentin. Materials and methods: Root canals of 72 extracted single-rooted teeth were prepared and teeth were fixed in microcentrifuge tubes with silicone impression material. After setting of the silicone, teeth were removed and split longitudinally in buccolingual direction. One half was used as control (pretreatment) while the other was placed into the tube (posttreatment). Then specimens were divided into six test groups (three with and three without PIPS activation). The irrigants tested were 2.5% NaOCl, 17% EDTA, and 2% CHX. Experimental tooth specimens were irrigated with 6 mL of test solution, with additional PIPS activation applied to the PIPS groups. Then specimens were subjected to Vickers microhardness testing. Percentage change of microhardness was calculated. Energy dispersive X-ray spectroscopy (SEM-EDX) was performed to measure element content. Results: Among the irrigant-alone groups, NaOCl and CHX did not alter the dentin microhardness, whereas statistically lower microhardness values were obtained in EDTA group. Chemical composition of dentin was affected from all irrigants used. PIPS activation led to no additional alteration in dentin microhardness. PIPS significantly increased the phosphorus level in NaOCl group. Conclusions: Dentin microhardness was significantly affected by the irrigation solution, not by the PIPS activation.

The push-out bond strength of BIOfactor mineral trioxide aggregate, a novel root repair material.

OBJECTIVES: The aim of this in vitro study was to evaluate the push-out bond strength of a novel calcium silicate-based root repair material-BIOfactor MTA to root canal dentin in comparison with white MTA-Angelus (Angelus) and Biodentine (Septodont). MATERIALS AND METHODS: The coronal parts of 12 central incisors were removed and the roots were embedded in acrylic resin blocks. Midroot dentin of each sample was horizontally sectioned into 1.1 mm slices and 3 slices were obtained from each root. Three canal-like standardized holes having 1 mm in diameter were created parallel to the root canal on each dentin slice with a diamond bur. The holes were filled with MTA-Angelus, Biodentine, or BIOfactor MTA. Wet gauze was placed over the specimens and samples were stored in an incubator at 37°C for 7 days to allow complete setting. Then samples were subjected to the push-out test method using a universal test machine with the loading speed of 1 mm/min. Data was statistically analyzed using Friedman test and post hoc Wilcoxon signed rank test with Bonferroni correction. RESULTS: There were no significant differences among the push-out bond strength values of MTA-Angelus, Biodentine, and BIOfactor MTA (p > 0.017). Most of the specimens exhibited cohesive failure in all groups, with the highest rate found in Biodentine group. CONCLUSIONS: Based on the results of this study, MTA-Angelus, Biodentine, and BIOfactor MTA showed similar resistances to the push-out testing.

Dentinal tubule penetration of endodontic sealers after nonthermal plasma treatment: A confocal laser scanning microscopy study.

One of the factors affecting the success of endodontic treatment is to fill the root canal system hermetically. The aim of this in vitro study was to evaluate the effect of nonthermal plasma (NP) on dentinal tubule penetration of root canal sealers using confocal laser scanning microscopy. Forty mandibular premolar teeth were selected and the root canals were prepared with large-Waveone-Gold rotary-files. Specimens were divided into four experimental groups according to sealer and NP treatment (n = 10). G1: AH-Plus (AH) G2: nonthermal plasma application + AH-Plus(AH-P) G3: Endosequence-BC(BC) G4: nonthermal plasma application + Endosequence-BC(BC-P). Cold lateral-condensation technique was used for the obturation of root canals. The roots were sectioned horizontally and the sections were examined under confocal laser scanning microscopy. The maximum tubule penetration and percentage of penetration values were obtained from the microscopy images and were statistically analyzed with repeated measurements-ANOVA and the Tukey (HSD) test (p < 0.05). The percentages of dentinal tubule penetration of the groups were not statistically different. The maximum tubule penetration of the AH-P was statistically lower than that of the BC-P (p < 0.05). Plasma application had no affect on the percentage of dentinal tubule penetration. Under the conditions of this in vitro Endosequence-BC sealer showed higher maximum tubule penetration values than AH-Plus after NP treatment. Percentage of dentinal tubule penetration values of experimental groups was similar.

Evaluation of the Periodontal Disease Effect on Pulp Volume.

INTRODUCTION: The success of periodontal and endodontic treatments depends on the total recovery from both conditions regardless of their occurrence as independent or combined lesions. There is strong presumptive evidence that teeth with periodontal disease may cause pulpal inflammation and degeneration. Therefore, the goal of this study was to establish a correlation between periodontitis and pulp volume. METHODS: Thirty-four dental images from 17 patients obtained by cone-beam computed tomography were analyzed by medical software to create three-dimensional images. Paired t test analysis was used for statistical analysis. RESULTS: The statistical analysis showed that periodontitis had a significant effect on the volume and surface areas of the dental pulp (P < .05). CONCLUSIONS: The findings of this study showed that periodontitis causes pulp volume to reduce by approximately 20%. The use of three-dimensional models provides better understanding of the dental anatomy before endodontic treatment and, consequently, improvement of treatment outcomes. Additional studies are needed to investigate the effect of periodontal disease on pulp volume and surface area.

Tooth discoloration effects of calcium silicate based barrier materials used in revascularization and treatment with internal bleaching.

BACKGROUND/PURPOSE: Usage of barrier materials is an important step in revascularization procedure. One of the undesired properties of these barrier materials is to cause coronal tooth discoloration. The aim of this in vitro study was to evaluate the tooth discoloration induced by ProRoot MTA (PMTA), Biodentine, and MM-MTA, as well as the efficacy of internal bleaching on this discoloration. MATERIALS AND METHODS: Forty-two maxillary incisor teeth were prepared. Triple antibiotic paste (TAP) was placed in the root canals and incubated for 3 weeks. After removing the TAP, blood embedded spongostans were inserted into the root canals, and PMTA, Biodentine, or MM-MTA was placed over them. The teeth were incubated for 4 weeks at 37 °C; then, the internal bleaching agent was sealed for one week. The tooth color was measured throughout the study and the color change values (ΔE) of each specimen were calculated, and the data was statistically analyzed using the one-way ANOVA and Tamhane's T2 tests. RESULTS: The TAP significantly decreased the luminosity of the teeth (p < 0.05); however, no significant differences were observed between the tooth discolorations induced by the PMTA, Biodentine, and MM-MTA (p > 0.05). The teeth in the Biodentine group were more whitened than those of the PMTA and MM-MTA groups (p < 0.05). CONCLUSION: Although the PMTA, Biodentine, and MM-MTA caused similar color alterations in the teeth, more bleaching was observed on those teeth discolored using TAP + blood + Biodentine.

Efficacy of Twisted File Adaptive, Reciproc and ProTaper Universal Retreatment instruments for root-canal-filling removal: A cone-beam computed tomography study.

The aim of this study was to evaluate the efficacy of Twisted File (TF) Adaptive, Reciproc, and ProTaper Universal Retreatment (UR) System instruments for removing root-canal-filling. Sixty single rooted teeth were decoronated, instrumented and obturated. Preoperative CBCT scans were taken and the teeth were retreated with TF Adaptive, Reciproc, ProTaper UR, or hand files (n=15). Then, the teeth were rescanned, and the percentage volume of the residual root-canal-filling material was established. The total time for retreatment was recorded, and the data was statistically analyzed. The statistical ranking of the residual filling material volume was as follows: hand file=TF Adaptive>ProTaper UR=Reciproc. The ProTaper UR and Reciproc systems required shorter periods of time for retreatment. Root canal filling was more efficiently removed by using Reciproc and ProTaper UR instruments than TF Adaptive instruments and hand files. The TF Adaptive system was advantageous over hand files with regard to operating time.

Majewski osteodysplastic primordial dwarfism type II: clinical findings and dental management of a child patient.

Majewski osteodysplastic primordial dwarfism type II (MOPD II) is an unusual autosomal recessive inherited form of primordial dwarfism, which is characterized by a small head diameter at birth, but which also progresses to severe microcephaly, progressive bony dysplasia, and characteristic facies and personality. This report presents a case of a five-year-old girl with MOPD II syndrome. The patient was referred to our clinic with the complaint of severe tooth pain at the left mandibular primary molar teeth. Clinical examination revealed that most of the primary teeth had been decayed and all primary teeth were hypoplastic. Patient's history revealed delayed development in the primary dentition and radiographic examination showed rootless primary molar teeth and short-rooted incisors. The treatment was not possible due to the lack of root of the left mandibular primary molars; so the teeth were extracted. Thorough and timely dental evaluation is crucial for the prevention of dental problems and the maintenance of oral health in patients with MOPD II syndrome is of utmost importance.

Comparison of organic tissue dissolution capacities of sodium hypochlorite and chlorine dioxide.

The organic tissue dissolution properties of irrigating solutions are important for the success of endodontic treatment. Chlorine dioxide (ClO2) has been recently proposed as an irrigation solution in endodontics. The organic tissue dissolution property of sodium hypochlorite (NaOCl) is well-known and extensively investigated, but apparently no data have been published on tissue-dissolving properties of ClO2. The aim of this in vitro study was to compare organic tissue dissolution capacity of NaOCl and ClO2. In this study, 5.25% NaOCl, 13.8% ClO2, and, as a control, isotonic saline solutions (0.9% NaCl) were used. Thirty bovine pulp specimens were previously weighed and immersed for 20 minutes in each test solution (changing the solution every 2 minutes). The pulp specimens were then blotted dry and weighed again. The percentage of weight loss was calculated and statistically analyzed by using one-way analysis of variance and post hoc Tukey honestly significant difference tests. Saline solution did not dissolve the organic tissue. Both 5.25% NaOCl and 13.8% ClO2 dissolved the tissue pieces more effectively than saline control (P < .05). No statistically significant difference was found between the tissue-dissolving properties of 5.25% NaOCl and those of 13.8% ClO2 (P > .05). Within the limitations of this in vitro study, it was concluded that ClO2 and NaOCl are equally efficient for dissolving organic tissue.

Maxillary first molar with an unusual morphology: report of a rare case.

Variations in dental anatomy are found in all teeth. Knowledge of these variations, particularly concerning the location and treatment of all canals, is very important for the success of endodontic therapy, because the inability to find and properly treat the root canals may cause failures. Variations in canal morphology, such as extra canals, apical ramifications, apical deltas, or lateral canals, are commonly encountered, and their incidence and significance have been well documented. However, the clinician should also be aware of the possibility of the existence of fewer root and/or canal numbers. The goal of this clinical article is to describe root canal treatment in a maxillary first molar with the unusual morphology of a single root and a single canal.