One-year clinical observation of the effect of internal bleaching on pulpless discolored teeth.

OBJECTIVES: This study aimed to observe the color rebound and rebound rates of non-pulp discolored teeth within 1 year after routine internal bleaching to guide clinical practice and prompt prognosis. METHODS: In this work, the efficacy of bleaching was observed in 20 patients. The color of discolored teeth was measured by using a computerized colorimeter before bleaching; immediately after bleaching; and at the 1st, 3rd, 6th, 9th, and 12th months after bleaching. The L*, a*, and b* values of the color of cervical, mesial, and incisal parts of the teeth were obtained, and the color change amounts ΔE*, ΔL*, Δa*, and Δb* were calculated. The overall rebound rate (P*) and the color rebound velocity (V*) were also analyzed over time. RESULTS: In 20 patients following treatment, the average ΔE* of tooth color change was 14.99. After bleaching, the neck and middle of the teeth ΔE* and ΔL* decreased in the 1st, 3rd, 6th, 9th, and 12th months, and the differences were statistically significant. Meanwhile, from the 9th month after bleaching, the rebound speed was lower than that in the 1st month, and the difference was statistically significant. The incisal end of the tooth ΔE* and ΔL* decreased in the 6th, 9th, and 12th months after bleaching, and the differences were statistically significant. No significant difference was found in the rebound speed between time points. However, this rate settled after the 9th month, with an average color rebound rate of 30.11% in 20 patients. CONCLUSIONS: The results indicated that internal bleaching could cause a noticeable color change on pulpless teeth. The color rebound after bleaching was mainly caused by lightness (L*), which gradually decreased with time, and it was slightly related to a* and b*. The color of the teeth after internal bleaching rebounded to a certain extent with time, but the color rebound speed became stable from the 9th month. Clinically, secondary internal bleaching can be considered at this time according to whether the colors of the affected tooth and the adjacent tooth are coordinated and depending on the patient's needs.

Effect of non-vital tooth bleaching photoactivated with blue or violet LED on color and microhardness.

BACKGROUND: To evaluate the efficacy of dental bleaching protocols using 35% hydrogen peroxide photoactivated with violet LED on color and microhardness of endodontically treated teeth. METHODS: Forty specimens were selected and randomized into 4 groups (n = 10): C - Control, HP - 35% hydrogen peroxide, HP + BL - 35% hydrogen peroxide + blue LED, HP + VL - 35% hydrogen peroxide + violet LED. Three bleaching sessions were performed for each group. Color analysis was performed 7 days after each bleaching session. Two-way repeated measure ANOVA and Bonferroni test were used to evaluate the effect of different bleaching protocols and evaluation times on the dependent variables (∆E and ∆L). Dentin microhardness was measured 24 h after the third bleaching session. Data were evaluated by ANOVA and Tukey's test at a significance level of 5%. RESULTS: Differences on ∆E and ∆L were verified after the first and second bleaching sessions (p < 0.05) and showed stability after the third one, for all the groups. No differences were observed among HP, HP + BL, and HP + VL groups, regardless of the evaluation time (p > 0.05). HP and C showed the greatest and smallest reduction in dentin microhardness (p < 0.05), respectively. No difference between HP + BL and HP + VL protocols (P > 0.05) was observed. CONCLUSIONS: High concentration hydrogen peroxide (35%) photoactivated with violet LED bleached endodontically treated teeth effectively. However, the same protocol negatively affected the dentin microhardness, but not in the same level of 35% HP solely used.

Fracture resistance of endodontically treated premolars restored with CAD-CAM onlays.

PURPOSE: To evaluate the fracture resistance of endodontically treated premolars restored with CAD-CAM onlay restorations. METHODS: 60 extracted mandibular first premolars were selected and at first divided into three groups regarding treatment options: MOD onlay with buccal cusp coverage, MOD onlay with buccal cusp coverage + endodontic treatment, MOD onlay with buccal cusp coverage + endodontic treatment + fiber post. Then, all groups were divided into subgroups (n=10) according to the restorative material used: IPS e.max CAD and Lava Ultimate. Each group was submitted to 5,000 thermal cycles, embedded in acrylic resin and secured in a universal testing machine respectively. A compressive load was applied until fracture, at a crosshead speed of 0.5 mm/minute. Statistical significance among each group was analyzed using one-way ANOVA and Bonferroni tests. RESULTS: Statistically, endodontically treated IPS e.max onlays had numerically the lowest average fracture resistance [753.1 (± 224.9) N/mm² ] among all treatment options. IPS e.max onlays treated with fiber posts had significantly higher resistance than that of endodontically treated IPS e.max CAD group (P= 0.013). Endodontically treated teeth restored with Lava Ultimate onlays [1,381.0 (± 471.7) N/mm²] showed significantly higher averages of fracture resistance than IPS e.max CAD onlays. CLINICAL SIGNIFICANCE: CAD-CAM composite (resin nanoceramic) onlays resist greater forces compared to ceramic restorations. Fiber posts could improve the fracture resistance of endodontically treated mandibular premolars following the ceramic CAD-CAM onlays.

Clinical Testing of Walking Bleach, In-Office, and Combined Bleaching of Endodontically Treated Teeth.

Objective. The causes of internal posteruptive discoloration of teeth are bleeding, necroses, infections, and endodontic filling materials. The aim of this study was to establish the results of bleaching endodontically treated teeth using walking bleach, in-office, and combined techniques, using 30% carbamide peroxide and 35% hydrogen peroxide, as well as the effect of etiological factors, and the time elapsed after endodontic treatment on the success of bleaching. Materials and Methods. The research involved 30 endodontically treated teeth in healthy patients. Retroalveolar X-rays were taken to check the quality of root canal obturation. Endodontic treatment and obturation were carried out on the discolored non-vital teeth without any previous endodontic treatment. Before bleaching, two millimeters of the filling were removed from the root canal and the very entry into the canal was protected with glass ionomer cement. The teeth were divided into three groups, depending on the bleaching technique: walking bleach technique (10 patients), in-office technique (10 patients), and combined technique (10 patients). The teeth were bleached with 30% carbamide peroxide and 35% hydrogen peroxide. The bleaching procedure was repeated in all the patients three times. The color of all teeth was determined based on the Vita Classic guide before and after bleaching. The Χ2 square and Kruskal−Wallis tests were used to identify differences in teeth bleaching results. Results. A statistically significant difference (p < 0.05) was established between bleaching success and the time elapsed after endodontic treatment. There were no statistically significant differences observed between the bleaching success and etiological factors, bleaching techniques, or bleaching agents. Conclusions. The effectiveness of non-vital tooth bleaching is affected by the time elapsed after endodontic treatment.

Estabilidad del color en el blanqueamiento intracoronal / Color stability in intracoronal whitening

RESUMEN Introducción: El blanqueamiento intracoronal es una alternativa mínimamente invasiva que permite devolver el color a dientes no vitales tincionados. La estabilidad del color logrado es fundamental para evaluar la predictibilidad de este tipo de tratamiento. Objetivo: Evaluar la estabilidad del color 3 años después del blanqueamiento intracameral con peróxido de hidrógeno y carbamida a diferentes concentraciones. Métodos: Se utilizaron 44 premolares extraídos por indicación ortodóncica, los cuales fueron tratados endodónticamente y pigmentados artificialmente con cromógenos sanguíneos. Las muestras fueron divididas aleatoriamente en 4 grupos de estudio (n = 11) siendo: grupo A: peróxido de carbamida 37 por ciento, grupo B: peróxido de hidrógeno 35 por ciento, grupo C: peróxido de carbamida 100 por ciento y grupo D: control; para luego realizar 4 aplicaciones de agente blanqueador con un intervalo de 4 días entre cada aplicación. El registro del color se realizó mediante espectrofotometría, lo que permitió obtener los valores CIE L*a*b* para calcular la variación total de color entre los parámetros iniciales y finales del tratamiento, así como el control a los 3 años. Resultados: Los resultados fueron analizados mediante las pruebas de Shapiro-Wilks, ANOVA y Mann-Whitney, sin registrar diferencias significativas en la variación total de color al control de los 3 años (p > 0,05). Conclusión: Los resultados del blanqueamiento intracoronal, independiente del tipo y concentración del agente utilizado en este estudio son estables en el tiempo y cualquier variación regresiva de color debe ser atribuida a factores extrínsecos(AU)

ABSTRACT Introduction: Intracoronal whitening is a minimally invasive procedure to restore natural color to stained non-vital teeth. The color stability achieved is fundamental to evaluate the predictability of this type of treatment. Objective: Evaluate color stability 3 years after intracameral whitening with carbamide and hydrogen peroxide at various concentrations. Methods: A total 44 premolars were used which had been extracted by orthodontic indication. The premolars were treated endodontically and artificially pigmented with blood chromogenes. The samples were randomly divided into 4 study groups (n = 11): Group A: 37 percent carbamide peroxide, Group B: 35 percent hydrogen peroxide, Group C: 100 percent carbamide peroxide and Group D: control. Four applications were then made of the whitening agent with a 4-days' separation between them. Color was recorded by spectrophotometry, obtaining the values CIE L*a*b* to estimate total color variation between the initial and final parameters of the treatment, as well as control at 3 years. Results: The results were analyzed with Shapiro-Wilk, ANOVA and Mann-Whitney tests, not finding any significant differences in total color variation with respect to the 3 years' control (p > 0.05). Conclusion: The results of the intracoronal whitening studied are stable throughout time, regardless of the type and concentration of the agent used, and any regressive color variation should be attributed to extrinsic factors(AU)

Immediate tooth replantation: root canal filling for delayed initiation of endodontic treatment.

The aim of this study is to evaluate the action of paramonochlorophenol associated with Furacin followed by calcium hydroxide (CH) dressing in the control of inflammatory root resorption in cases of immediate tooth replantation with delayed endodontic treatment. A total of 28 incisors of 3 male dogs were extracted and replanted after 15 minutes, and randomly divided into 3 groups: Group I (n = 8) - endodontic treatment was performed before the extraction and replantation; Group II (n = 10) - endodontic treatment was performed 30 days after replantation and the root canal was filled with CH dressing; Group III (n = 10) - endodontic treatment was performed 30 days after replantation and root canals received temporary medication of paramonochlorophenol-Furacin followed by CH dressing. The animals were euthanized 90 days after replantation. The histomorphological events analyzed at the epithelial reattachment site were the intensity and extent of acute and chronic inflammatory processes, periodontal ligament (PDL) organization, the intensity and extent of acute and chronic inflammatory processes in the PDL space, root resorption, bone tissue, and ankylosis. Data were submitted to the Wilcoxon Signed Ranks Test for group comparison (α = 5%). In Groups I, II and III the periodontal ligament was regenerated and most of the resorption areas were repaired by newly formed cementum. The depth and extent of root resorption were significantly higher in Group II than in Group III. The use of paramonochlorophenol-furacin followed by CH dressing was more effective in controlling inflammatory root resorption after immediate tooth replantation.

Immediate tooth replantation: root canal filling for delayed initiation of endodontic treatment

Abstract The aim of this study is to evaluate the action of paramonochlorophenol associated with Furacin followed by calcium hydroxide (CH) dressing in the control of inflammatory root resorption in cases of immediate tooth replantation with delayed endodontic treatment. A total of 28 incisors of 3 male dogs were extracted and replanted after 15 minutes, and randomly divided into 3 groups: Group I (n = 8) - endodontic treatment was performed before the extraction and replantation; Group II (n = 10) - endodontic treatment was performed 30 days after replantation and the root canal was filled with CH dressing; Group III (n = 10) - endodontic treatment was performed 30 days after replantation and root canals received temporary medication of paramonochlorophenol-Furacin followed by CH dressing. The animals were euthanized 90 days after replantation. The histomorphological events analyzed at the epithelial reattachment site were the intensity and extent of acute and chronic inflammatory processes, periodontal ligament (PDL) organization, the intensity and extent of acute and chronic inflammatory processes in the PDL space, root resorption, bone tissue, and ankylosis. Data were submitted to the Wilcoxon Signed Ranks Test for group comparison (α = 5%). In Groups I, II and III the periodontal ligament was regenerated and most of the resorption areas were repaired by newly formed cementum. The depth and extent of root resorption were significantly higher in Group II than in Group III. The use of paramonochlorophenol-furacin followed by CH dressing was more effective in controlling inflammatory root resorption after immediate tooth replantation.

Mineral trioxide aggregate-induced apical closure in nonvital immature permanent maxillary incisor.

Treatment of nonvital immature permanent teeth with calcium hydroxide is associated with few difficulties such as weakened tooth root, root canal reinfection, and long treatment time. Mineral trioxide aggregate (MTA) apical plug method is an alternative treatment method for open apices and has gained popularity in the recent times. This case report describes the management of a late-referral case of periapically involved, traumatized immature permanent incisor by endodontic treatment and the use of MTA apical plug. After preparing the access cavity, the working length was determined. The root canals were irrigated with 3% sodium hypochlorite and disinfected with metapex for 2 weeks. MTA was then placed in the apical 3 mm of the root canal. The remaining part of the root canal was filled with thermoplastic gutta-percha, and the coronal restoration was finished with composite resin. After 1-year follow-up, radiograph showed successful healing of periradicular radiolucency.

Clinical and Radiographic Assessment of the Efficacy of a Collagen Membrane in Regenerative Endodontics: A Randomized, Controlled Clinical Trial.

INTRODUCTION: Recent reviews confirm a general lack of randomized, controlled clinical studies on the efficacy of regenerative endodontics in immature teeth affected by pulp and periapical diseases. Moreover, we have no evidence of the curative efficacy of collagen membranes used as scaffolds in regenerative endodontics. Here, we evaluated whether a Bio-Gide collagen membrane (Geistlich Pharma AG, Wolhusen, Switzerland) has efficacy in promoting dentin formation in regenerative endodontics. METHODS: Forty-three patients yielding a total of 46 nonvital immature teeth were divided randomly into 2 groups. Subsequent to chemomechanical preparation, regenerative endodontics with (the experimental group) and without (the control group) Bio-Gide were performed. All cases were followed up clinically and radiographically every 3 months for at least 6 months. Quantitative analyses using an imaging program yielded percentage changes in root dimensions based on a comparison between preoperative and recall radiographs. RESULTS: The results of 40 patients (43 teeth) were included in the final analyses. All patients from both groups showed clinical success with complete resolution of signs and symptoms. Radiographically, the thickness of the dentin wall at the middle third of the root was higher for the experimental group than the control group. However, other indicators were comparable between both groups. CONCLUSIONS: The use of the Bio-Gide collagen membrane promoted the development of the dentin wall in the middle third of the root in patients undergoing regenerative endodontic procedures. The convenience of operation and the assured positioning of the sealing material make the Bio-Gide collagen membrane especially suitable for handling wide root canals.

Efeito de diferentes sistemas de obturação na resistência à fratura de raízes tratadas endodonticamente / The Influence of different obturation systems on the fracture resistance of endodontically treated roots

Objective: This study aimed to compare the fracture resistance of endodontically treated roots filled by different obturation systems. Material and methods: Ninety-six maxillary central incisors were used and decoronated, retaining 12 mm of the roots. On the basis of obturation systems, the roots were randomly divided into 4 groups (n=24): Group1 (COGR): control group (unprepared, unfilled), Group 2 (AVGR): ActiV GP points/ActiV GP sealer, Group 3 (GPGR): Gutta percha points / AH plus sealer, and Group4 (GAGR): Gutta percha points/ActiV GP sealer. The last three groups were obturated with the single cone technique. The roots were then stored in 100% relative humidity at 37 °C for 2 weeks. A vertical compressive force was exerted in a universal testing machine until fracture occurred. Data were statistically analyzed using one-way ANOVA. Results: Mean (SD) failure loads for groups ranged from 920.51 ± 210.37 to 1113.44 ± 489.42 N. The fracture resistance between the different study groups indicated no statistical difference (p>0.05). Conclusions: ActiV GP system did not exert a significant effect on the fracture resistance of endodontically treated teeth.(AU)

Objective: Comparar a resistência à fratura de raízes tratadas endodonticamente obturadas através de diferentes sistemas. Materiais e Métodos: Noventa e seis incisivos centrais superiores foram utilizados, tiveram as coroas removidas, restando 12 mm de raíz. De acordo com o sistema de obturação, as raízes foram divididas em 4 grupos (n=24): Grupo1 (COGR): grupo controle (sem preparo, sem preenchimento), Grupo2 (AVGR): cones ActiV GP / cimento ActiV GP, Grupo3 (GPGR): cones de guta percha / cimento AH plus, e Grupo4 (GAGR): cones de guta percha / cimento ActiV GP. Os últimos três grupos foram obturados através da técnica de cone único. As raízes foram armazenadas em 100% de umidade relativa a 37 °C durante 2 semanas. Uma força compressiva vertical foi aplicada através de uma máquina de ensaio universal até ocorrer fratura. Os dados foram analisados estatisticamente através de ANOVA ­ 1 fator. Resultados: A carga média (SD) obtida no momento da falha variou entre 920.51 ± 210.37 até 1113.44 ± 489.42 N. A resistência à fratura entre os diferentes grupos estudados não indicaram diferença estatística. Conclusão: O sistema ActiV GP não exerceu um efeito significante na resistência à fratura em dentes tratados endodonticamente.(AU)

Effects of alpha-tocopherol on fracture resistance after endodontic treatment, bleaching and restoration.

This study evaluated the effects of 10% alphatocopherol on the fracture resistance of endodontically treated teeth subjected to tooth bleaching with hydrogen peroxide and immediately restored with composite resin. Fifty bovine incisors were selected, including 10 sound teeth that constituted the control group (G1 (C)). The remaining 40 teeth, which were endodontically treated, were divided into four groups (n = 10): G2 (CR), consisting of teeth immediately restored with composite resin; G3 (HP + CR), consisting of teeth subjected to tooth bleaching with 38% hydrogen peroxide and immediately restored with composite resin; G4 (HP + SA + CR), which received treatment similar to that used for G3, but with 10% sodium ascorbate gel applied after the bleaching protocol; and G5 (HP + AT + CR), which was similar to G4 but included 10% alphatocopherol gel as an antioxidant. After 24 h, composite restorations were performed, and teeth were subjected to a fracture resistance test at a speed of 0.5 mm/min in an electromechanical testing machine. The axial force was applied with an angle of incidence of 135° relative to the long axis of the root. Data were subjected to ANOVA and Tukey tests (p = 0.05). G1 exhibited the highest fracture resistance (p < 0.05). No significant differences among the other experimental groups were observed. The 10% sodium ascorbate and 10% alphatocopherol gels did not improve the fracture resistance of endodontically treated teeth subjected to bleaching with 38% hydrogen peroxide.

Tratamiento con pasta 3 Mix-MP en molares primarios no vitales: estudio preliminar / Treatment of nonvital primary molars with 2 Mix-MP paste: a preliminary study

Estimar la frecuencia de éxito clínico-radiográfico del tratamiento endodóntico no instrumentado con pasta 3Mix-MP en molares primarios con diagnóstico de necrosis pulpar. Materiales y métodos: estudio experimental, prospectivo y longitudinal, realizado en la Cátedra de Odontología Integral Niños de la FOUBA (agosto 2014 - agosto 2015). Formaron parte de la investigación 44 molares primarios con diagnóstico de necrosis pulpar, de 36 niños (6,07 +/- 1,63 años), sin compromiso inmunológico ni metabólico y que junto con sus responsables legales brindaron el consentimiento informado. Se realizó el tratamiento endodóntico no instrumentado con pasta 3Mix-MP (metronidazol, minociclina, ciprofloxacina 1:1:1 y vehículos macrogol, propilenglicol 1:1) y restauración definitiva con corona de acero. Los molares fueron evaluados por dos examinadores al mes, 3, 6 y 12 meses. Se calcularon porcentajes con sus intervalos de confianza del 95 por ciento. Resultados: al mes, la tasa de éxito clínico fue de 97.72 por ciento (87.96-99.97) y la de éxito radiográfico de 93.18 por ciento (81.31-98.61). Fue posible el seguimiento del 65.85 por ciento de la muestra a los 3 meses, del 34.14 por ciento a los 6 meses y del 24.39 por ciento a los 12 meses, revelando un 100 por ciento de éxito clínico-radiográfico en los tratamientos evaluados. Conclusión: en los casos y períodos estudiados, esta terapéutica mostró un buen comportamiento clínico y radiográfico. Son necesarios estudios con mayor tamaño muestral y mayor período de seguimiento para proponerla como alternativa de tratamento...

Effects of alpha-tocopherol on fracture resistance after endodontic treatment, bleaching and restoration

Abstract This study evaluated the effects of 10% alphatocopherol on the fracture resistance of endodontically treated teeth subjected to tooth bleaching with hydrogen peroxide and immediately restored with composite resin. Fifty bovine incisors were selected, including 10 sound teeth that constituted the control group (G1 (C)). The remaining 40 teeth, which were endodontically treated, were divided into four groups (n = 10): G2 (CR), consisting of teeth immediately restored with composite resin; G3 (HP + CR), consisting of teeth subjected to tooth bleaching with 38% hydrogen peroxide and immediately restored with composite resin; G4 (HP + SA + CR), which received treatment similar to that used for G3, but with 10% sodium ascorbate gel applied after the bleaching protocol; and G5 (HP + AT + CR), which was similar to G4 but included 10% alphatocopherol gel as an antioxidant. After 24 h, composite restorations were performed, and teeth were subjected to a fracture resistance test at a speed of 0.5 mm/min in an electromechanical testing machine. The axial force was applied with an angle of incidence of 135° relative to the long axis of the root. Data were subjected to ANOVA and Tukey tests (p = 0.05). G1 exhibited the highest fracture resistance (p < 0.05). No significant differences among the other experimental groups were observed. The 10% sodium ascorbate and 10% alphatocopherol gels did not improve the fracture resistance of endodontically treated teeth subjected to bleaching with 38% hydrogen peroxide.

Regenerative endodontic therapy: a data analysis of clinical protocols.

INTRODUCTION: The aim of the present study was to systematically analyze the protocols that have been used in regenerative endodontic therapy and to detect any variations in clinical procedures. METHODS: An electronic search was executed in PubMed using appropriate Medical Subject Heading terms covering the period from January 1993 to May 2014. Additional publications from hand searching and the reference section of each relevant article enriched the article list. The relevance of each article was initially evaluated by scanning all titles and corresponding abstracts. The definite inclusion of each article in the study was determined by using specific criteria applied independently by 3 reviewers. RESULTS: Sixty relevant publications were finally included. The canal walls were not mechanically instrumented in 68% of the clinical articles. Sodium hypochlorite was included in 97% of the clinical studies either as the only irrigant or in combination with other irrigants. Antibiotic combination paste was used as the intracanal medicament in 80% of the clinical articles. Sodium hypochlorite, chlorhexidine, and EDTA were used in the final irrigation protocol in 75%, 4%, and 13% of the clinical studies, respectively. Neither the creation of a blood clot nor the use of platelet-rich plasma/platelet-rich fibrin was described in 13% of the clinical articles. Mineral trioxide aggregate was used as an intracanal coronal barrier in 85% of the relevant clinical studies. CONCLUSIONS: The variability of the clinical protocols applied during regenerative enododontic procedures is considerably high. A thorough analysis of regenerative protocols may constitute an additional source to provide useful clinical considerations for REPs.

Treatment of abscessed primary molars utilizing lesion sterilization and tissue repair: literature review and report of three cases.

PURPOSE: The purpose of this report was to review an emerging alternative treatment to pulpectomies and extractions for nonvital primary teeth called lesion sterilization and tissue repair (LSTR) and provide the results of three clinical case applications. LSTR is a noninstrumentation endodontic treatment that involves a triantibiotic mixture in a propylene glycol vehicle, which is used to disinfect root canal systems. This concept was developed by the cariology research unit of the School of Dentistry, Niigata University, Niigata, Niigata Prefecture, Japan. This article reviews the development of the technique, clinical procedures required for the technique, three clinical applications and radiographic documentation and follow-up, and a short literature review of the current evidence supporting its application in clinical practice.

Intracanal delivery of Resolvin E1 controls inflammation in necrotic immature rat teeth.

INTRODUCTION: Pulp necrosis in immature teeth and the resulting periodontal apical inflammation negatively affect root formation. Resolvin E1 (RvE1) is a lipid-derived endogenous pro-resolution molecule that controls inflammation. The aim of this investigation was to evaluate the impact of RvE1 applied as an intracanal medication on root formation in nonvital immature teeth. METHODS: To arrest root development, pulpectomy was performed in the lower first molars of 4-week-old Wistar rats. After 3 weeks, irrigation with 2.5% sodium hypochlorite and 0.9% sterile saline was performed, and either a triple antibiotic paste (TAP) or RvE1 in saline was applied into the root canals. In the control group, access openings drilled into molars were left exposed to the oral environment. Root development and periapical repair were evaluated radiographically and histologically at 3 and 6 weeks after treatment. RESULTS: RvE1 reduced periapical lesion size compared with the control at 3 weeks, which was similar to TAP. Inflammatory response in the RvE1-treated group was markedly reduced compared with both TAP and control specimens. At 6 weeks, root development was observed in both groups, but RvE1 treatment produced less cellularity with more regular calcified tissue deposition. CONCLUSIONS: RvE1 and TAP had a positive impact on reducing inflammation and promoting root formation. RvE1 was more effective in reducing inflammation at earlier stages. RvE1 has potential to be used as root canal dressing to control inflammation in endodontically compromised teeth before complete root formation. Stability of RvE1 within the root canal and its delivery are issues to be addressed before its clinical use.

A national survey of pediatric dentists on antibiotic use in children.

PURPOSE: The purposes of this study were to: (1) examine the antibiotic prescribing practices of pediatric dentists and adherence to professional guidelines; and (2) assess their knowledge of and attitudes toward antibiotic resistance. METHODS: A cross-sectional survey regarding antibiotic use, resistance, and knowledge of antibiotic stewardship programs was emailed to 4,636 members of the American Academy of Pediatric Dentistry (AAPD). RESULTS: 987 surveys (21 percent) were completed; 984 were analyzed. Lack of adherence to AAPD antibiotic guidelines was noted. There was a trend toward overuse of antibiotics for the following conditions: irreversible pulpitis with (32 percent) and without vital pulp (42 percent); localized dentoalveolar abscess with (68 percent) and without draining fistula (39 percent); mitral valve relapse with regurgitation (43 percent); intrusion (15 percent); extrusion (13 percent); and rheumatoid arthritis (12 percent). Determinants of antibiotic use were: facial swelling (88 percent); pain relief (15 percent); unavailable appointment for several weeks (six percent); and parental satisfaction (four percent). Although 98 percent of respondents believed that antibiotic resistance is of growing concern, only 15 percent were aware of antibiotic stewardship programs. CONCLUSION: AAPD members overprescribe antibiotics. Educational programs to increase knowledge of antibiotic resistance and stewardship programs should be implemented to increase adherence to professional guidelines.

Induced migration of dental pulp stem cells for in vivo pulp regeneration.

Dental pulp has intrinsic capacity for self-repair. However, it is not clear whether dental pulp cells can be recruited endogenously for regenerating pulp tissues, including mineralizing into dentin. This work is based on a hypothesis that dental pulp stem/progenitor cells can be induced to migrate by chemotactic cytokines and act as endogenous cell sources for regeneration and mineralization. Dental stem cells (DSCs) were isolated from adult human tooth pulp and seeded on the surfaces of 3D collagen gel cylinders that were incubated in chemically defined media with stromal-derived factor-1α (SDF1), basic fibroblast growth factor (bFGF), or bone morphogenetic protein-7 (BMP7). Significantly more cells were recruited into collagen gel by SDF1 or bFGF than without cytokines in 7 days, whereas BMP7 had little effect on cell recruitment. BMP7, however, was highly effective, equally to dexamethasone, in orchestrating mineralization of cultured DSCs. Cell membrane receptors for SDF1, bFGF, and BMP7 were up-regulated in treated DSCs. Upon in vivo delivery, bFGF induced re-cellularization and re-vascularization in endodontically treated human teeth implanted into the dorsum of rats. Thus, endogenous dental pulp cells, including stem/progenitor cells, may be recruited and subsequently differentiated by chemotaxis of selective cytokines in the regeneration of dental pulp.