Periapical bacterial disinfection is critical for dental pulp regenerative cell therapy in apical periodontitis in dogs.

BACKGROUND: Application of pulp regenerative cell therapy for mature teeth with periapical lesions is a critical clinical challenge. The bacterial infection in inaccessible location within the root canal system and in the periapical lesions could cause resistance and impediment, leading to limitations in successful therapy. Thus, the aim of this study was to examine the effect of residual bacteria on the outcome of pulp regeneration in mature teeth with apical periodontitis in dogs. METHODS: Periapical lesions were induced in 32 root canals of 4 dogs in two different models in severities, model A and model B. Model A (moderate infection): the canal exposed to the oral cavity for 2 weeks and then closed for 2 weeks. Model B (severe infection): the canal exposed to the oral cavity for 2 months and then closed for 5 months. All root canals were irrigated with 6% sodium hypochlorite, and 3% EDTA and further with 0.015% levofloxacin-containing nanobubbles, which was also used as an intracanal medicament. The aseptic conditions were examined by bacterial anaerobic culture and/or PCR analyses. The root canal treatment was repeated several times, and allogeneic dental pulp stem cells were transplanted into the root canals. The radiographic evaluation of periapical lesions was performed by cone-beam computed tomography before the first treatment, just after cell transplantation, and after 2 months and 6 months in both model A, model B, respectively. The animals were then sacrificed and the jaw blocks were harvested for histological and histobacteriological evaluations of pulp regeneration and periapical tissue healing. Furthermore, the DiI-labelled DPSCs were transplanted into the root canals after complete disinfection (n = 4) or without root canal treatment (n = 4) in the apical periodontitis model (model A) in one dog, and cell localization was compared 72 h after transplantation. RESULTS: In 8 out of 12 canals from model A, and 10 out of 15 canals from model B, pulp regeneration with good vascularization, innervation, and a significant reduction in the radiolucent area of the periapical lesions were observed. However, in the other 4 canals and 5 canals from model A and model B, respectively, no pulp tissue was regenerated, and inflammation in the periapical tissue, and external resorption or healed external resorption were detected. The presence of residual bacteria in the periapical tissues and severe inflammation were significantly associated with inhibition of regenerated pulp tissue in these 9 unsuccessful canals (P < 0.05, each) (OR = 0.075, each) analyzed by multiple logistic regression analysis. For cellular kinetics, transplanted cells remained in the disinfected root canals, while they were not detected in the infected root canals, suggesting their migration through the apical foramen under the influence of inflammation. CONCLUSIONS: A true pulp-dentin complex was regenerated in the root canal by the pulp regenerative therapy in mature teeth with apical lesions. The successful pulp regeneration was negatively associated both with residual bacteria and inflammation in the periapical tissue.

Accelerating Wound Healing of Traumatic Ulcer with Topical Application of Dental Pulp Mesenchymal Stem Cell Secretome and Robusta Green Coffee Bean Extract Combination in vivo

ABSTRACT Objective: To investigate the ability of a combination dental pulp mesenchymal stem cell secretome (DPMSCS), robusta green coffee bean extract (RGCBE), and Carboxymethylcellulose-Natrium (CMC-Na) in a Wistar rats model of traumatic ulcers. Material and Methods: Twenty-eight young, male, healthy Wistar rats (Rattus norvegicus) were divided into seven groups randomly: Group K0, group K1-3 (traumatic ulcer rats that received CMC-Na gel for three days), group K1-7 (traumatic ulcer rats that received CMC-Na gel for seven days), group K2-3 (traumatic ulcer rats that received RGCBE for three days), group K2-7 (traumatic ulcer rats that received RGCBE for seven days), group K3-3 (traumatic ulcer rats that received DPMSCS for three days), and group K3-7 (traumatic ulcer rats that received DPMSCS for seven days). An ulcer was made with an amalgam stopper on the right buccal mucosa of the rats. DPMSCS 50% gel was applied to the ulcer on the left buccal mucosa. The ulcer diameter was measured on day 3 and day 7. Results: There was a significant difference in the diameter of the ulcer, the number of neutrophils, and fibroblasts in the treatment group compared to the control group on day 7. Conclusion: A combination of DPMSCS and RGCBE 50% accelerates traumatic ulcer wound healing by lowering ulcer diameter, decreasing neutrophil counts, and increasing fibroblast proliferation in vivo.

Nuclear receptor coactivator 4-mediated ferritinophagy drives proliferation of dental pulp stem cells in hypoxia.

Nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy has been implicated in the ferroptosis in cancer cells and hematopoiesis in the bone marrow. However, the role of iron metabolism, especially NCOA4-mediated degradation of ferritin, has not been explored in the proliferation of mesenchymal stem cells. The present study was designed to explore the role of NCOA4-mediated ferritinophagy in hypoxia-treated dental pulp stem cells (DPSCs). Hypoxia treatment increased ROS generation, boosted cytosolic labile iron pool, increased expression of transferrin receptor 1 and NCOA4. Moreover, colocalization of LC3B with NCOA4 and ferritin was observed in hypoxia-treated DPSCs, indicating the development of ferritinophagy. Hypoxia promoted the proliferation of DPSCs, but not ferroptosis, under normal serum supplement and serum deprivation. NCOA4 knock-down reduced ferritin degradation and inhibited proliferation of DPSCs under hypoxia. Furthermore, the activation of hypoxia inducible factor 1α and p38 mitogen-activated protein kinase signaling pathway was involved in the upregulation of NCOA4 in hypoxia. Therefore, our present study suggested that NCOA4-mediated ferritinophagy promoted the level of labile iron pool, leading to enhanced iron availability and elevated cell proliferation of DPSCs. Our present study uncovered a physiological role of ferritinophagy in the proliferation and growth of mesenchymal stem cells under hypoxia.

Analgesic and Neuroprotective Effects of Electroacupuncture in a Dental Pulp Injury Model-A Basic Research.

Irreversible pulpitis is an extremely painful condition and its consequence in the central nervous system (CNS) remains unclear. A mouse model of dental pulp injury (DPI) resembles the irreversible pulpitis profile in humans. This study sought to determine whether pain induced by DPI activates microglia and astrocytes in the trigeminal subnucleus caudalis (Vc), as well as increases levels of proinflammatory cytokines, and whether electroacupuncture (EA) can be a potential analgesic and neuroprotective therapy following DPI. Pain behavior was measured via head-withdrawal threshold (HWT) and burrowing behavior at days 1, 3, 7, 14 and 21 after DPI. A marked decrease in HWT and burrowing activity was observed from day 1 to 14 after DPI and no changes were seen on day 21. Microglial and astrocytes activation; along with high cytokine (TNFα, IL-1ß, and IL-6) levels, were observed in the Vc at 21 days after DPI. These effects were attenuated by verum (local and distal) EA, as well as oral ibuprofen administration. The results suggest that DPI-induced pain and glial activations in the Vc and EA exert analgesic efficacy at both local and distal acupoints. Furthermore, verum (local and distal) EA might be associated with the modulations of microglial and astrocytes activation.

Terapia fotodinâmica como coadjuvante ao tratamento endodôntico: relato de caso / Photodynamic therapy as an endodontic treatment coadjuvant: case report

Introdução: a terapia fotodinâmica surgiu na Endodontia como um método de tratamento que utiliza a laserterapia de baixa potência, com ação analgésica, anti-inflamatória e antibacteriana. Objetivo: o presente trabalho visa apresentar e discutir, por meio do relato de um caso de tratamento endodôntico, o uso de terapia fotodinâmica como um aliado contra bactérias persistentes após o preparo químico-mecânico do canal. Relato de caso: paciente com 40 anos de idade, apresentou-se em consultório particular com dor pulsátil, sensível à percussão, com diagnóstico de periodontite apical aguda no dente #22. Após anamnese, exames radiográficos e odontometria, o tratamento endodôntico foi realizado com o sistema ProTaper® Universal (Dentsply), técnica híbrida, irrigação com hipoclorito de sódio 2,5% e agitação ultrassônica associada; e o elemento foi instrumentado e seco. Então, foi aplicada a terapia fotodinâmica: o corante azul de metileno 0,005% foi aplicado no canal seco durante 5 minutos, seguido de laser vermelho por 180 segundos, totalizando 18J (Laser DUO Portátil-MMO®), com movimentos de apical para incisal. Na sequência, nova irrigação de NaOCl e, então, EDTA 17%, com agitação ultrassônica por um minuto, seguido de NaOCl 2,5%, para se obter a neutralização do meio. Após secagem do canal, a obturação foi realizada com um cone único F3 (ProTaper® Universal) e cimentação com AH Plus®. Conclusão: a terapia fotodinâmica é um método de fácil e rápida aplicação, que surgiu como um coadjuvante ao tratamento endodôntico, sendo indicada para a eliminação de microrganismos persistentes após o preparo químico-mecânico dos canais radiculares (AU).

Introduction: Photodynamic therapy appears in endodontics as a treatment method that uses low level laser therapy with analgesic, anti-inflammatory and antibacterial. Goal: This paper aims to present and discuss through an endodontic treatment using photodynamic therapy as an ally against persistent bacteria after chemical-mechanical canal preparation. Case report: GR patient, 40, appeared in private practice, with throbbing pain, sensitive to shock, with acute apical periodontitis, the element 22. After anamnesis, X-ray examinations and tooth, endodontic treatment was performed with the system ProTaper Universal® (Dentsply), hybrid technique; irrigation with sodium hypochlorite 2.5%, ultrasonic agitation associated; instrumented and dry. Then it was applied to photodynamic therapy, 0.005% methylene blue dye was applied in the dry channel for 5 minutes followed by red laser for 180 seconds totaling 18J (Portable Laser DUO-MMO®) with the apex moves to the incisal, the new sequence NaOCl irrigation and after EDTA 17% with ultrasonic agitation for one minute followed by 2.5% NaOCl for neutralizing medium; Dry the canal obturation was performed with the single cone F3 ProTaper® Universal and cementation with AHPLUS®. Conclusion: We conclude that photodynamic therapy is a method of quick and easy application that comes as an adjunct to endodontic treatment, and is indicated for the elimination of persistent microorganisms after chemical-mechanical preparation of root canals (AU).

Pulp pathosis associated with ancient Maya dental inlays.

OBJECTIVE: The ancient Maya used to practice dental inlays as part of the cultural traditions. Most of those inlays remain in place after more than one thousand years. The purpose of this paper is to investigate the incidence of pulp pathosis associated with ancient Maya dental inlays to assess the impact that such common practice had on the population's oral health. DESIGN: We scored 193 anterior inlaid teeth from 107 pre-Hispanic Maya dentitions studied at three archaeological storage facilities (Universidad Autonoma de Yucatan, Harvard University, Atlas of Guatemala Project). Two hundred eleven untreated frontal teeth of pre-Hispanic Mayan collections were used as controls. We performed macroscopic, radiographic and microscopic analyses to assess the frequency of caries, pulp calcifications, internal root resorption (IRR), and periapical lesions (PALs). RESULTS: In the inlaid teeth, the frequencies of pulp calcifications, IRR, caries and PALs were 59.8%, 2.2%, 18.5% and 19.2%, respectively. Compared with untreated teeth, inlaid specimens exhibited greater susceptibility to caries, pulp calcifications, IRR and PALs than untreated teeth (pulp calcifications: 44.5%, IRR: 0%, caries: 1.4%, and PAL: 1.9%). Age-at-death did not have any significant influence on susceptibility to pulp calcifications, IRR, caries or PALs. CONCLUSIONS: We noted relatively low pulp irritation and a low frequency of carious infections, IRR and PALs in Mayan inlaid teeth. However, these levels exceeded the frequencies of untreated teeth from the same area and time period. We follow that the cements used by the pre-Hispanic Maya to fix the inlays into their sockets provided excellent sealing characteristics on average.

[Optimization of reparative dentinogenesis in experimental osteoporosis]. / Optimizatsiia reparativnogo dentinogeneza pri éksperimental'nom osteoporoze.

The aim of the study was to assess histochemical changes of the dental pulp in direct pulp capping/experimental osteoporosis animal model. The study was performed on 20 two-year sheep with simulated acute pulpitis divided in 2 groups: main (15 animals/120 teeth) and control (5 animals/40 teeth). Direct pulp capping in the main group included tissue-engineered structure composed of a hydrogel PuraMatrix/3DM with ectomesenchymal stem cells immobilized on collagen sponge. In the control group collagen sponges with hydrocortisone furatsilin, chondroitin sulfate, аnaesthesinum were used for the same purpose. Dentinal bridge formation was much slower in controls than in the main group. Developed tissue-engineered design optimizes each stage of the healing process by protecting the pulp from infection, reduction of exudation, hemostatic effect and in long term contributes to a significant acceleration of the formation of the dentinal bridge.

Effect of low-level laser therapy (λ780 nm) on the mechanically damaged dentin-pulp complex in a model of extrusive luxation in rat incisors.

In order to regenerate the dental pulp, many strategies have been developed as phototherapy. In the pulp repair, we do not know if gallium-aluminum-arsenide (GaAlAs) laser preserves the primary odontoblasts or stimulates the formation of more dentin matrix when dental pulp is damaged. The aim of the present study was to examine the effect of laser phototherapy (λ780 nm) on vascularization, inflammation, density of the primary odontoblast layer, and formation of reactionary and reparative dentin in the dental pulp by provoking extrusion of the rat incisor. The upper incisors were extruded 3 mm and then repositioned into their original sockets followed by a laser irradiation of the palatal mucosa (λ = 780 nm; p = 70 mW; CW; 4.2 J/cm2; 60 s) every 48 h. Non-traumatized and/or non-irradiated incisors were used as the controls. At 8 and 30 days after surgery, incisors were processed for histological and histomorphometric analysis. Morphological analysis revealed no differences in vascularization between groups, but showed discrete inflammation in some non-irradiated and injured specimens, which correlated with a more irregular reparative dentin. The density of primary odontoblasts in the groups treated with lasers was higher when compared to non-irradiated groups, but no statistically significant difference between groups (p > 0.05). The thickness of the tertiary dentin was increased in both traumatized groups with no statistically significant difference between non-irradiated and irradiated groups (p > 0.05).The present findings revealed that the GaAlAs laser induced small changes on dentin-pulp complex, with more regular dentin matrix in the irradiated dental pulps.

The Histone-Deacetylase-Inhibitor Suberoylanilide Hydroxamic Acid Promotes Dental Pulp Repair Mechanisms Through Modulation of Matrix Metalloproteinase-13 Activity.

Direct application of histone-deacetylase-inhibitors (HDACis) to dental pulp cells (DPCs) induces chromatin changes, promoting gene expression and cellular-reparative events. We have previously demonstrated that HDACis (valproic acid, trichostatin A) increase mineralization in dental papillae-derived cell-lines and primary DPCs by stimulation of dentinogenic gene expression. Here, we investigated novel genes regulated by the HDACi, suberoylanilide hydroxamic acid (SAHA), to identify new pathways contributing to DPC differentiation. SAHA significantly compromised DPC viability only at relatively high concentrations (5 µM); while low concentrations (1 µM) SAHA did not increase apoptosis. HDACi-exposure for 24 h induced mineralization-per-cell dose-dependently after 2 weeks; however, constant 14d SAHA-exposure inhibited mineralization. Microarray analysis (24 h and 14 days) of SAHA exposed cultures highlighted that 764 transcripts showed a significant >2.0-fold change at 24 h, which reduced to 36 genes at 14 days. 59% of genes were down-regulated at 24 h and 36% at 14 days, respectively. Pathway analysis indicated SAHA increased expression of members of the matrix metalloproteinase (MMP) family. Furthermore, SAHA-supplementation increased MMP-13 protein expression (7 d, 14 days) and enzyme activity (48 h, 14 days). Selective MMP-13-inhibition (MMP-13i) dose-dependently accelerated mineralization in both SAHA-treated and non-treated cultures. MMP-13i-supplementation promoted expression of several mineralization-associated markers, however, HDACi-induced cell migration and wound healing were impaired. Data demonstrate that short-term low-dose SAHA-exposure promotes mineralization in DPCs by modulating gene pathways and tissue proteases. MMP-13i further increased mineralization-associated events, but decreased HDACi cell migration indicating a specific role for MMP-13 in pulpal repair processes. Pharmacological inhibition of HDAC and MMP may provide novel insights into pulpal repair processes with significant translational benefit. J. Cell. Physiol. 231: 798-816, 2016. © 2015 Wiley Periodicals, Inc.

Histological Evaluation of Allium sativum Oil as a New Medicament for Pulp Treatment of Permanent Teeth.

OBJECTIVE: The objective of this study was to evaluate the histo pathology effects of two medicaments Allium sativum oil and formocresol on the remaining pulp tissue of the permanent teething children. MATERIALS AND METHODS: A total of 18 premolars were included in this study. Two sound premolars were extracted and subjected to histological examination to show the normal pulp tissue. Pulpo tomy procedure was performed in the rest of the remaining 16 premolars; half of them using Allium sativum oil and the rest of the tested premolars were medicated using formocresol and all were sealed with suitable restoration. Then, premolars extracted at variable intervals (48 hours, 2 weeks, 1 month, 2 months), stained using hemotoxylin and eosin etain (H&E) and prepared for histopathology examination. RESULTS: Histological evaluation seemed far more promising for Allium sativum oil than formocresol. Histological evaluation revealed that teeth treated with Allium sativa oil showed infammatory changes that had been resolved in the end of the study. On the contrary, the severe chronic infammation of pulp tissue accompanied with formocresol eventually produced pulp necrosis with or without fibrosis. In addition, pulp calcification was evidenced in certain cases. CONCLUSION: Allium sativum oil is a biocompatible material that is compatible with vital human pulp tissue. It offers a good healing potential, leaving the remaining pulp tissue healthy and functioning.

Treatment of dentinal hypersensitivity by means of Nd:YAP Laser: a preliminary in vitro study.

OBJECTIVE: The aim of this study is to evaluate the effectiveness of Nd:YAP laser to seal dentinal tubules at different parameters. MATERIAL AND METHODS: 24 caries-free human wisdom impacted molars were used. The crowns were sectioned transversally in order to totally expose the dentin. The smear layer was removed by a 1 min application of EDTA. Each surface was divided into four quadrants, but only three quadrants were irradiated at a different output power setting (irradiation speed: 1 mm/sec; optical fiber diameter: 320 µm; tangential incidence of beam and in noncontact mode). Samples were smeared with a graphite paste prior to laser irradiation. All specimens were sent for SEM analysis. Pulp temperature increases in additional twenty teeth were measured by a thermocouple. RESULTS: Morphological changes in dentin surfaces depend on the value of used energy density. Higher energy densities (2 W-4 W; 200-400 mJ; pulse duration: 100 m sec.; and 10 Hz) induce higher dentin modifications. Our results confirmed that Nd:YAP laser irradiations can lead to total or partial occlusion of dentin tubules without provoking fissures or cracks. Measurements of pulp temperature increases showed that Nd:YAP laser beam can be considered as harmless for pulp vitality for following irradiation conditions: 2 W (200 mJ) to 4 W (400 mJ) with an irradiation speed of 1 mm/sec; fiber diameter: 320 micrometers; 10 Hz; pulse duration: 100 m sec; noncontact mode and in tangential incidence to exposed dentin. The perpendicular incidence of the laser beam on exposed dentin may injure pulp vitality even at low output power of 3 W. CONCLUSIONS: Nd:YAP laser beam was able to seal the dentin tubules without damaging dentinal surfaces and without harming pulp vitality. Nd:YAP laser is effective and may be safely used for future in vivo treatments of dentinal hypersensitivity under certain conditions.

Avaliação da atividade biológica de células-tronco da polpa dental humana submetida à irradiação laser de baixa intensidade / Evaluation of biological activity of stem cells from human dental pulp subjected to low-intensity laser irradiation

O laser de baixa intensidade (LBI) tem sido utilizado com a finalidade de promover cicatrização e regeneração dos tecidos. A literatura mostra um efeito positivo do LBI na proliferação celular, porém pouco se sabe sobre a sua eficácia na proliferação de célulastronco dentais. O objetivo deste estudo foi avaliar o efeito da irradiação do LBI na atividade biológica de células-tronco da polpa de dente permanente (DPSCs). Extratos de polpa dental foram isolados de cinco terceiros molares hígidos removidos por indicação cirúrgica e/ou ortodôntica. Após a digestão enzimática, as células foram caracterizadas e cultivadas em meio de cultura αMEM suplementado com antibióticos e 15% de soro fetal bovino. No terceiro subcultivo, as células foram irradiadas com um laser diodo InGaAlP, utilizando-se duas diferentes densidades de energia (0,5 J/cm2 - 16 segundos e 1,0 J/cm² - 33 segundos), comprimento de onda de 660nm e potência de 30mW. Uma nova irradiação, utilizando os mesmos parâmetros, foi realizada 48 h após a primeira. Um grupo controle (não irradiado) foi mantido nas mesmas condições experimentais de cultivo. A fim de avaliar a proliferação celular, foram utilizados o método exclusão por Azul de Tripan e a viabilidade celular medida através do ensaio de MTT, nos intervalos de 24, 48, 72 e 96 h após a primeira aplicação do laser. Nos mesmos intervalos foram avaliados os eventos do ciclo celular. Eventos relacionados à morte celular foram analisados por citometria de fluxo nos intervalos de 24 e 72 horas. Os dados das contagens celulares foram submetidos a testes estatísticos não paramétricos de Kruskal-Wallis e Mann-Whitney, considerando um intervalo de confiança de 95%. Os resultados mostraram que os dois grupos irradiados exibiram uma curva de proliferação mais ascendente, com diferença estatisticamente significante (p<0,05) em relação ao grupo controle nos intervalos de 72 e 96h, sem alterações consideráveis na viabilidade celular ao longo do experimento. A distribuição das células nas fases do ciclo celular foi coerente com células em proliferação nos três grupos. Os resultados da curva de crescimento, MTT, Anexina/PI e Ciclo celular foram concordantes, dessa forma é possível concluir que o LLLI, principalmente com dose de 1,0J/cm 2 , seja uma terapia de grande importância para o futuro da engenharia tecidual e medicina regenerativa envolvendo DPSCs, uma vez que neste estudo o LLLI contribuiu com o crescimento e viabilidade celular. (AU)

The low-level laser therapy (LLLT) has been used in order to improve wound healing and tissue regeneration. The literature shows a positive effect of LLLT on cell proliferation, but little is known about its effectiveness on the proliferation of dental pulp stem cells. The aim of this study was to evaluate the effect of irradiation LLLT on biological activity of dental pulp stem cells from permanent teeth (DPSCs). Dental pulp extracts were isolated from healthy five third molars removed by surgical and/or orthodontic indication. After enzymatic digestion, the cells were examined and cultured in αMEM supplemented with antibiotics and 15% fetal bovine serum. On the third subculture, the cells were either irradiated with a laser diode InGaAlP, using two different energy densities (0.5 J/cm2 - 16 seconds and 1.0 J / cm ² - 33 seconds), wavelength of 660nm and power of 30mW. A new irradiation using the same parameters was performed 48 hours after the first. A control group (non-irradiated) was kept under the same experimental conditions of culture. Cell proliferation was evaluated by Trypan blue exclusion method and by measuring mitochondrial activity using the MTT-based cytotoxicity assay, at intervals of 24, 48, 72 and 96 h after the first laser application. Events of the cell cycle were evaluated in the same intervals, and the events related to cell death were analyzed by flow cytometry in the ranges of 24 to 72 hours. Data from cell counts were submitted to non-parametric Kruskal-Wallis and Mann-Whitney test, considering a confidence interval of 95%. The results showed that the both groups irradiated exhibited an upward cell proliferation curve, with statistically significant difference (p < 0.05) compared to the control group in intervals of 72 and 96 hours. No significant changes were observed in cell viability throughout the experiment. The distribution of the cells in the cell cycle phases was consistent with proliferating cells in all three groups. The results of growth curve, MTT, Anexin/PI and cell cycle were concordant, then it is possible conclude that the LLLI, especially with the dose of 1,0J/cm2 , it is a therapy of great importance for the future of tissue engineering and regenerative medicine involving stem cells, once in this study it contributed to the growth and viability of DPSCs. (AU)

[Efficiency and safety of local anesthesia in teeth with mild and moderate periodontal disease].

The rationale for the choice of local anesthesia in teeth with mild to moderate periodontal disease was formulated based on a comparative analysis of the effectiveness and safety of different local anesthesia methods with 4% articaine. Effectiveness of anesthesia was assessed using objective values of electric study of pulp sensitivity and registration of microcirculation in dental pulp. Safety analysis was based on changes in periodontal tissues microcirculation assessed by laser Doppler flowmetry, as well as of central hemodynamics rates.

Dentine sensitivity: past, present and future.

OBJECTIVE: This review defines dentine sensitivity (DS), its prevalence, its aetiology, the mechanism(s) responsible for DS, its diagnosis and its treatment. The review then examines the modes of action of various treatments for DS including potassium salts, strontium salts, bioglasses, arginine/calcium carbonate and professional treatments such as adhesives and oxalates. The methods used to evaluate the various treatment modalities are discussed, including laboratory studies and randomised controlled clinical trials. DATA SOURCES AND STUDY SELECTION: A literature search was conducted using PubMed, Ovid Medline and Cochrane reviews for information on DS and its treatments, as well as laboratory and clinical studies used to evaluate the efficacy of various DS treatments. With regard to efficacy of treatments for DS only reports of clinical studies that were randomised, controlled and blinded were reviewed. The authors offer new insights into the shortcomings of the recent systematic review of the use of oxalates for DS. CONCLUSION: The authors introduce the concept of a novel desensitising mouthrinse containing 1.4% potassium oxalate: Listerine® Advanced Defence Sensitive mouthrinse. Readers of this supplement issue of the Journal of Dentistry are invited to review the significance of managing the clinical problem of DS. They are also invited to assess data from laboratory and randomised controlled clinical studies in order to understand the advantages offered by regular use of 1.4% potassium oxalate-containing mouthrinse, Listerine Advanced Defence Sensitive, in particular its resistance to daily erosive and/or abrasive challenges.

LED light attenuation through human dentin: a first step toward pulp photobiomodulation after cavity preparation.

PURPOSE: To evaluate the transdentinal light attenuation of LED at three wavelengths through different dentin thicknesses, simulating cavity preparations of different depths. METHODS: Forty-two dentin discs of three thicknesses (0.2, 0.5 and 1 mm; n = 14) were prepared from the coronal dentin of extracted sound human molars. The discs were illuminated with a LED light at three wavelengths (450+/-10 nm, 630 +/-10 nm and 850 +/-10 nm) to determine light attenuation. Light transmittance was also measured by spectrophotometry. RESULTS: In terms of minimum (0.2 mm) and maximum (1.0 mm) dentin thicknesses, the percentage of light attenuation varied from 49.3% to 69.9% for blue light, 42.9% to 58.5% for red light and 39.3% to 46.8% for infrared. For transmittance values, an increase was observed for all thicknesses according to greater wavelengths, and the largest variation occurred for the 0.2 mm thickness. All three wavelengths were able to pass through the dentin barrier at different thicknesses. Furthermore, the LED power loss and transmittance showed wide variations, depending on dentin thickness and wavelength.

Should pulp chamber pulpotomy be seen as a permanent treatment? Some preliminary thoughts.

AIM: To investigate the benefits of pulpotomy (to the level of the floor of the pulp chamber) as an endodontic treatment for teeth with vital pulps. METHODOLOGY: Seventeen patients, aged 7-54 years (mean of 37.2 year), were treated by pulpotomy and filling with ProRoot MTA(®) in premolar or molar teeth with vital pulps and without clinical evidence of irreversible pulpitis. The patients were then followed up for 12 to 24 months and the teeth then assessed by clinical and radiographic examination. Statistical analysis was performed with Kaplan-Meier survival probability statistics to estimate the survival of the treated teeth. RESULTS: At 24 months, the survival rate without any complementary treatment was estimated to be 82%. Two of the 17 treated teeth required root canal treatment for pain control and one for prosthetic reasons. CONCLUSIONS: Under the conditions of this study, pulpotomy offered a viable alternative to root canal treatment for teeth with vital pulps in the short term. However, there is insufficient clinical evidence to consider this technique for the treatment of every permanent tooth. Nevertheless, it should be considered as a potential alternative approach to be further developed for future applications.

Nigella sativa oil as a pulp medicament for pulpotomized teeth: a histopathological evaluation.

PURPOSE: Concerns about the safety of formocresol (FC) as a pulpotomy agent in Pediatric Dentistry have lead to the search of new capping medicaments. Indigenous plant medicines such as Nigella Sativa (NS) have been the focus of many researches. Therefore the purpose of this study was to investigate histo-pathologically the pulp response to NS oil and FC in dogs. METHOD: Forty teeth in 4 male dogs of undefined breed aging 12-14 months were used in this study. Coronal access cavities were performed on the upper and lower premolars so that both medicaments were tested in the same animal in alternate sides of the mouth. Four weeks after treatment the animals were sacrificed, paraffin sections were prepared for histological, histochemical and immuno-histochemical staining. RESULTS: Specimens in the NS group showed mild to moderate vasodilatation. Few specimens showed scattered inflammatory cell infiltration and the odontoblastic layer was continuous. While the FC group showed moderate to severe vasodilatation with high inflammatory cell infiltrate and degenerative changes. CONCLUSIONS: NS possesses an anti-inflammatory effect and the pulp maintains its vitality after its application, which could qualify its use as a pulp medicament for pulpotomized teeth in clinical practice.

Dental caries in Rome, 50-100 AD.

Scarce information exists on the clinical features of dental caries in the Imperial Roman population and no structural data on caries lesions from this period have so far been published. We report on the findings of 86 teeth (50-100 AD) found during archaeological excavations of the temple of Castor and Pollux in the Forum Romanum. We found that nearly all teeth had large carious cavities extending into the pulp. The distribution and size of the caries lesions were similar to those found in contemporary adult populations in Africa and China living without access to dental care. Most lesions had a hypermineralized zone in the dentin at the advancing front of the carious cavities as revealed by micro-computed tomography. This biological dentin reaction combined with the morphology of the cavities might indicate that some temporary topical pain relief and intervention treatment slowed down the rate of lesion progression. This is indirectly supported by examination of cavities of similar size and depth from a contemporary population without access to dental health care. In contrast to the lesions in the Roman teeth, these lesions did not exhibit a hypermineralized dentin reaction. We investigated whether the Pb isotopic composition of enamel and/or dentin of a single tooth matched that of a sample of an ancient Forum water lead pipe. The Pb isotopic composition of the tooth did not match that of the tube, suggesting that the subjects were exposed to different Pb sources during their lifetime other than the lead tubes.

A biochemical and histopathological evaluation of generalized pulp calcification in young permanent teeth.

Pulp calcifications are a frequent finding on bitewing and periapical radiographs in older age-groups but their occurrence in the entire dentition in young subjects is unusual. We report such an unusual occurrence of generalized pulp calcification in a 13-year-old Indian female. Radiographic examination of the dentition revealed pulp calcifications in all permanent teeth, located mostly in the pulp chamber but with some in the root canals. The patient's dental, medical, and family history was noncontributory. Biochemical analysis of the removed pulp calcification from one of the teeth during endodontic treatment showed large amounts of calcium, phosphorus, and carbonate. However, metabolic evaluation of patient through liver and kidney function tests and other blood investigations did not reveal any metabolic disorder. The patient was also evaluated for any systemic, syndromic, or genetic involvement but this was also noncontributory. Therefore, we propose that this unusual case of generalized pulp calcification is of idiopathic origin. In this work, histopathological and biochemical evaluations of the pulp calcification was done to try and understand the initiation and progress of calcifications in pulpal tissue.

Is endodontic treatment performed under general anaesthesia technically acceptable?

OBJECTIVES: Undertaking endodontic treatment under general anaesthesia (GA) is often described as difficult and hazardous, but no study reports on safe and efficacious conditions for endodontic treatment under GA. This study aims to evaluate whether compromises made for the endodontic treatment of permanent teeth under GA are acceptable. It describes the quality of endodontic treatment undertaken in two series of consecutive patients treated either under GA or local anaesthesia (LA). MATERIALS AND METHODS: Post-operative data sheets and periapical radiographs were collected for 255 permanent teeth treated under GA during a 4-year period (GA group, 125 patients with special needs) and for 246 permanent teeth treated under local anaesthesia over 7 months (LA group, 180 healthy patients). The radiographic criteria for quality of endodontic treatment (RCQET) were considered satisfactory when (1) the root filling was within 2 mm of the apex; (2) the filling displayed no voids or defects; and (3) all the visible canals had been obturated. The type of tooth, pulpal status and periapical status were considered independent variables for RCQET. RESULTS: The proportion of satisfactory RCQET reached 63% in both groups and differed by type of tooth, being significantly lower for molars than for other teeth. CONCLUSION: From a technical point of view, compromises made for the endodontic treatment of permanent teeth under GA are acceptable. Further studies should be conducted to evaluate the long-term success of endodontic treatment performed under GA. CLINICAL RELEVANCE: This study supports the feasibility of endodontic treatment for patients treated under GA.