Aspectos clínicos y forenses del color rosa de los dientes: reporte de un caso / Clinical and forensic aspects of the pink color of teeth: report of a case

La coloración rosa de los dientes puede originarse por diferentes factores. En el ámbito forense se ha descrito al fenómeno denominado post mortem pink teeth como un signo asociado a muertes violentas de etiología diversa. En la práctica clínica también es posible observar pacientes con dientes rosados, fre-cuentemente ocasionados por traumatismos o iatro-genia proveniente de ortodoncia, cuyo mecanismo de producción obedece a distintas etiopatogenias, destacándose las reabsorciones dentinarias inter-nas, cemento-dentinarias externas y calcificaciones dentinarias. El presente artículo expone el caso de un individuo adulto con antecedente de trauma óseo-dentario por accidente vial que, luego de un prolon-gado tiempo, asiste al Servicio de Urgencias Odon-tológicas y Orientación de Pacientes de la Facultad de Odontología de la Universidad de Buenos Aires, en donde se le detecta, a modo de hallazgo exploratorio, una ostensible coloración rosada en el canino infe-rior derecho. La situación motivó un pormenorizado abordaje clínico y radiográfico, indagando respecto a los probables factores que intervinieron en su ge-neración y desarrollo (AU)

The pink coloration of the teeth can be caused by dif-ferent factors. In the forensic field, the phenomenon called post mortem pink teeth has been described as a sign associated with violent deaths of various etiology. In clinical practice, it is also possible to ob-serve patients with pink teeth, frequently caused by trauma or iatrogenesis from orthodontics, whose production mechanism is due to different etiopatho-genesis, highlighting internal dentin resorption, ex-ternal cemento-dentinal resorption and dentin calci-fications. This article presents the case of an adult individual with a history of bone-dental trauma due to a road accident who, after a long time, attends the Dental Emergency and Patient Guidance Service of the Faculty of Dentistry of the University of Bue-nos Aires, where an ostensible pink coloration was detected in the lower right canine as an exploratory finding. The situation motivated a detailed clinical and radiographic approach, inquiring about the probable factors that intervened in its generation and development (AU)

Evaluación del estatus del tejido pulpar postratamiento oncológico / Assessment of the status of the pulp tissue post oncological treatment

La OMS cataloga al cáncer como uno de los principales problemas en el ámbito mundial, los pacientes sometidos a terapia oncológica son más vulnerables a desarrollar complicaciones en los tejidos de la cavidad bucal entre las que tenemos: mucositis, infecciones, osteorradionecrosis. En el manejo endodóntico hay que tomar en consideración que los trata- mientos como yodoterapia, radioterapia y quimioterapia pueden generar efectos sobre el complejo dentinopulpar. El objetivo de este artículo es determinar el estatus del tejido pulpar postratamiento oncológico mediante la revisión sistemática en bases de datos de gran relevancia científica, como PubMed, Scielo, Medigraphic, Science direct. Se concluye que el sistema estomatognático es un receptor importante de estos efectos y secuelas en pacientes con terapia oncológica, el tejido pulpar no está libre de estas secuelas ya que genera daño celular, como la hipovascularidad, hipocelularidad e hipoxia la cual incrementa el riesgo de necrosis de la región (AU)

The WHO lists cancer as one of the main problems worldwide, patients undergoing oncological therapy are more vulnerable to developing complications in the tissues of the oral cavity among which we have: mucositis, infections, osteoradionecrosis. In endodontic management, it should be taken into consideration that treatments such as iodine therapy, radiotherapy, and chemotherapy can generate effects on the dentin-pulp complex. This article aims to determine the status of the pulp tissue after oncologic treatment. Through a systematic review in databases of great scientific relevance, such as PubMed, Scielo, Medigrafhic, Science direct. It is concluded that the stomatognathic system is an important receptor of these effects and sequelae in patients with oncological therapy, the pulp tissue is not free of these sequelae as it generates cellular damage because of the hypo vascularity, hypocellularity, and hypoxia which increases the risk of necrosis of the region (AU)

Establishment and neural differentiation of neural crest-derived stem cells from human dental pulp in serum-free conditions.

The potential of obtaining cell cultures with neural crest resemblance (neural crest-derived stem cells [NCSCs]) from dental-related tissues, including human dental pulp cells (hDPCs), has been discussed in the literature. However, most reports include the use of serum-rich conditions and do not describe the potential for neural differentiation, slowing translation to the clinic. Therefore, we aimed to culture and characterize NCSCs from the human dental pulp in vitro and evaluate their ability to differentiate into neurons; we also investigated the effectiveness of the addition of BMP4 to enhance this potential. Cultures were established from a varied cohort of patient samples and grown, as monolayers, in serum, serum-free, and also under sphere-aggregation conditions to induce and identify a NCSC phenotype. hDPC cultures were characterized by immunocytochemistry and reverse transcription quantitative polymerase chain reaction. Monolayer cultures expressed stem cell, neural progenitor and neural crest-related markers. Culturing hDPCs as neurospheres (hDPC-NCSCs) resulted in an increased expression of neural crest-related genes, while the addition of BMP4 appeared to produce better NCSC characteristics and neural differentiation. The neural-like phenotype was evidenced by the expression of TUJ1, peripherin, NFH, TAU, SYN1, and GAP43. Our results describe the establishment of hDPC cultures from a large variety of patients in serum-free medium, as NCSC that differentiate into neural-like cells, as well as an important effect of BMP4 in enhancing the neural crest phenotype and differentiation of hDPCs.

Evoked and spontaneous pain assessment during tooth pulp injury.

Injury of the tooth pulp is excruciatingly painful and yet the receptors and neural circuit mechanisms that transmit this form of pain remain poorly defined in both the clinic and preclinical rodent models. Easily quantifiable behavioral assessment in the mouse orofacial area remains a major bottleneck in uncovering molecular mechanisms that govern inflammatory pain in the tooth. In this study we sought to address this problem using the Mouse Grimace Scale and a novel approach to the application of mechanical Von Frey hair stimuli. We use a dental pulp injury model that exposes the pulp to the outside environment, a procedure we have previously shown produces inflammation. Using RNAscope technology, we demonstrate an upregulation of genes that contribute to the pain state in the trigeminal ganglia of injured mice. We found that mice with dental pulp injury have greater Mouse Grimace Scores than sham within 24 hours of injury, suggestive of spontaneous pain. We developed a scoring system of mouse refusal to determine thresholds for mechanical stimulation of the face with Von Frey filaments. This method revealed that mice with a unilateral dental injury develop bilateral mechanical allodynia that is delayed relative to the onset of spontaneous pain. This work demonstrates that tooth pain can be quantified in freely behaving mice using approaches common for other types of pain assessment. Harnessing these assays in the orofacial area during gene manipulation should assist in uncovering mechanisms for tooth pulp inflammatory pain and other forms of trigeminal pain.

Comparison of Pulp Sensibility Tests Responses in Type 2 Diabetes Patients and Healthy Individuals.

INTRODUCTION: Diabetes is a common disease that may have some influence on sensory nerves. The aim of this study was to evaluate dental pulp responses to 2 pulp sensibility tests (ie, cold and electric) in patients with type 2 diabetes compared with healthy individuals. METHODS: Three hundred twenty-two premolar teeth in 51 patients who had type 2 diabetes and 347 premolar teeth in 53 individuals with no medical conditions were investigated. The patients with type 2 diabetes were unified and had fasting plasma glucose <300, hemoglobin A1C <10, less than a 10-year history of diabetes mellitus, and no history of hypertension. Electric and cold pulp sensibility tests were performed for all teeth. The cold test results were recorded by the Heft-Parker visual analog scale, and the electric pulp test results were recorded based on the pulp tester's grade that evoked a response. RESULTS: There was no statistically significant difference between upper and lower premolar teeth in healthy individuals compared with the patients with diabetes in response to the cold and electric pulp tests (P > .05). In the patients with diabetes, the response of their upper premolars to the cold test was significantly reduced in diabetic patients >45 years of age (ß = -1.15, P = .013). However, there was no significant correlation between the cold test and age in the lower premolars of both diabetic and nondiabetic participants (P > .05). There was also no significant correlation between the need for a higher number of the electric pulp test current to evoke a response in maxillary and mandibular premolars of the patients with diabetes and nondiabetic participants with age (P > .05). CONCLUSIONS: There was a significant correlation between the reduction of maxillary premolar teeth responses to the cold test in diabetes patients >45 years of age.

Urgência em Endodontia: diagnóstico e tratamento em casos de pulpite irreversível sintomática / Urgency in Endodontics: Diagnosis and Treatment in Cases of Symptomatic Irreversible Pulpitis

Objetivo: discutir sobre o diagnóstico e a conduta terapêutica em casos de urgência endodôntica em dentes que apresentam pulpite irreversível sintomática. Material e Métodos: realizou-se uma revisão bibliográfica de estudos publicados nos últimos 5 anos (2015- 2020) por meio de busca nas bases de dados: PubMED, BVS (Biblioteca Virtual em Saúde) e Scielo (Scientific Eletronic Library). Para a pesquisa, foram utilizados os seguintes descritores: Pulpite Irreversível (Irreversible Pulpitis), Tratamento (Treatment), Dor (Pain) e Endodontia (Endodontics). Resultados: O diagnóstico é um passo fundamental no tratamento das urgências e emergências de origem endodôntica, pois é a partir do correto diagnóstico que será instituído o tratamento correto, reestabelecendo o conforto do paciente. Quando o profissional dispõe de tempo suficiente para realizar a remoção do tecido pulpar e o preparo do canal radicular, esse é o tratamento de escolha para os casos de pulpite irreversível sintomática, o qual pode ser realizado em sessão única ou em múltiplas sessões. Quando o profissional não dispõe de tempo suficiente para realizar o tratamento endodôntico convencional, a opção de tratamento é realizar apenas o atendimento de urgência para retirar o paciente do quadro de dor aguda presente, e em um momento futuro realizar o tratamento endodôntico completo. Conclusão: As urgências endodônticas sempre estão presentes nos consultórios odontológicos, os profissionais devem estar sempre preparados para realizar um correto diagnóstico e tratamento para cada caso, trazendo assim conforto ao paciente.

Objective: to discuss the diagnosis and therapeutic management in cases of endodontic urgency in teeth with symptomatic irreversible pulpitis. Material and Methods: a bibliographic review of studies published in the last 5 years (2015-2020) was carried out by searching the databases: PubMED, BVS (Virtual Health Library) and Scielo (Scientific Electronic Library). For the research, the following descriptors were used: Irreversible Pulpitis, Treatment, Pain and Endodontics. Results: The diagnosis is a fundamental step in the treatment of urgencies and emergencies of endodontic origin, as it is from the correct diagnosis that the correct treatment will be instituted, reestablishing the patient's comfort. When the professional has enough time to remove the pulp tissue and prepare the root canal, this is the treatment of choice for cases of symptomatic irreversible pulpitis, which can be performed in a single session or in multiple sessions. When the professional does not have enough time to carry out the conventional endodontic treatment, the treatment option is to perform only emergency care to remove the patient from the present acute pain condition, and at a future time to carry out the complete endodontic treatment. Conclusion: Endodontic emergencies are always present in dental offices, professionals must always be prepared to carry out a correct diagnosis and treatment for each case, thus bringing comfort to the patient.

Terapia endodóntica en pacientes adultos mayores ¿qué debemos tener en cuenta? / Endodontic therapy in elderly patients, what should we consider?

De acuerdo con la tendencia mundial, el número de personas de 60 años y más va en aumento. Este crecimiento demográfico de la población, el aumento de las expectativas de vida de las personas y la tendencia a la disminución de pacientes edéntulos, produce una mayor demanda de procedimientos endodónticos en la población anciana. Es fundamental que el odontólogo conozca la fisiología del envejecimiento para poder abordar, en forma eficaz, el tratamiento en los pacientes pertenecientes a este grupo etario. Se ha descripto que los tejidos dentales sufren cambios a lo largo de la vida; entre ellos, la reducción del número de fibroblastos, de odontoblastos, de vasos sanguíneos y de fibras nerviosas; el aumento de fibras colágenas, de masas calcificadas, aposición de cemento, de dentina secundaria y de dentina de reparación. El objetivo del presente trabajo es realizar una revisión bibliográfica en relación a los cambios que presentan la pulpa dental, la dentina y el cemento, relacionados con el proceso de envejecimiento y sus posibles dificultades al momento de realizar el tratamiento endodóntico; sin olvidar cómo pueden inferir en el éxito del tratamiento las posibles patologías sistémicas que presentan los pacientes a consecuencia de la edad (AU)

According to the world trend, the number of people aged 60 and over is increasing. This demographic growth of the population, the increase in people's life expectancies and the tendency to decrease edentulous patients, produces a greater demand for endodontic procedures in the elderly population. It is essential that the dentist knows the physiology of aging to be able to effectively address the treatment in patients belonging to this age group. It has been described that dental tissues suffer changes throughout life, including the reduction of the number of fibroblasts, odontoblasts, blood vessels and nerve fibers; the increase of collagen fibers, calcified masses, apposition of cement, secondary dentin and repair dentin. The objective of the present work is to carry out a bibliographic review in relation to the changes that the dental pulp, dentine and cement have in relation to the aging process and its possible consequences in the endodontic treatment; without forgetting how it can infer in the success of the treatment the possible systemic pathologies that patients present as a result of age (AU)

Ion Channels Involved in Tooth Pain.

The tooth has an unusual sensory system that converts external stimuli predominantly into pain, yet its sensory afferents in teeth demonstrate cytochemical properties of non-nociceptive neurons. This review summarizes the recent knowledge underlying this paradoxical nociception, with a focus on the ion channels involved in tooth pain. The expression of temperature-sensitive ion channels has been extensively investigated because thermal stimulation often evokes tooth pain. However, temperature-sensitive ion channels cannot explain the sudden intense tooth pain evoked by innocuous temperatures or light air puffs, leading to the hydrodynamic theory emphasizing the microfluidic movement within the dentinal tubules for detection by mechanosensitive ion channels. Several mechanosensitive ion channels expressed in dental sensory systems have been suggested as key players in the hydrodynamic theory, and TRPM7, which is abundant in the odontoblasts, and recently discovered PIEZO receptors are promising candidates. Several ligand-gated ion channels and voltage-gated ion channels expressed in dental primary afferent neurons have been discussed in relation to their potential contribution to tooth pain. In addition, in recent years, there has been growing interest in the potential sensory role of odontoblasts; thus, the expression of ion channels in odontoblasts and their potential relation to tooth pain is also reviewed.

Finite element analysis of the dental pulp under orthodontic forces.

INTRODUCTION: To evaluate the stress at the apical third of the pulp and neurovascular bundle (NVB) during 5 types of orthodontic movement at different levels of bone loss. Furthermore, correlations among bone loss, orthodontic appliances, and stress increase were assessed. METHODS: Based on cone-beam computed tomography datasets, 10 models of the mandibular second premolar were created. Each of these models was subjected to a gradual horizontal bone loss simulation (0-8 mm). Orthodontic forces of 20 g, 60 g, and 120 g were applied during the finite element analysis (FEA). For each bone loss level, stress values were evaluated with the use of Abaqus at the apical third of the pulp and the NVB. RESULTS: The stress manifested at the apical third of the pulp was smaller than that at the NVB. The highest apical NVB stress was found for rotation (0.000546 N/mm2 for 8 mm bone loss) whereas the lowest stress resulted after translational movements (2.35E-04 MPa for 8 mm bone loss). The FEA showed that Proffit's indicated orthodontic forces did not significantly disturb the pulpal blood flow and damage the apical NVB. Up to a doubling of the NVB stress, bone loss correlated with the force reduction to obtain similar stress levels compared with teeth with no bone loss. CONCLUSIONS: The present findings indicate that the stress manifested at the apical third of the pulp is smaller than that at NVB. Rotational movements induce the highest stress and translational forces develop the lowest stress related to the physiologic capillary blood pressure. Furthermore, in situations with reduced periodontium, lower forces are needed to reach the maximum tolerable stress compared with teeth with intact periodontium.

[The efficacy of electroodontodiagnosis by means of various types of current]. / Éffektivnost' élektroodontodiagnostiki s pomoshch'iu razlichnykh vidov toka.

THE PURPOSE OF THE STUDY: determination of the optimal parameters of the action of various types of current, which have the most pronounced irritating effect on the receptor apparatus of the tooth pulp. The study involved 102 volunteers aged 19 to 72 years (53 females and 49 males). The study was conducted on 217 teeth: 86 molars, 25 premolars, 19 canines and 98 incisors. 137 (63%) teeth were intact, in 48 (22%) teeth caries were found, in 32 (15%) teeth there was pulpitis or teeth were depulpated. Electroexcitability of the teeth was determined with the help of various types of electric current: an impulse variable, an impulse constant and a sinusoidal variable. The optimal current for carrying out an electroodontodiagnosis proved to be sinusoidal variable current with a frequency of 50 Hz. This current does not cause polarization of tissues, it is easy to dose, it causes a clear, but not painful sensation, gives the smallest spread of the indicators during repeated studies. The obtained results allowed formulating requirements for electroodontodiagnosis devices.

Activation of trigeminal ganglion satellite glial cells in CFA-induced tooth pulp pain in rats.

This study further investigated the mechanisms underlying the rat model of tooth pulp inflammatory pain elicited by complete Freund's adjuvant (CFA), in comparison to other pulpitis models. Pulps of the left maxillary first molars were accessed. In the CFA group, the pulps were exposed, and CFA application was followed by dental sealing. In the open group, the pulps were left exposed to the oral cavity. For the closed group, the pulps were exposed, and the teeth were immediately sealed. Naïve rats were used as negative controls. Several parameters were evaluated at 1, 2, 3 and 8 days. There was no statistical significant difference among the groups when body weight variation, food or water consumption were compared. Analysis of serum cytokines (IL-1ß, TNF or IL-6) or differential blood cell counts did not reveal any evidence of systemic inflammation. The CFA group displayed a significant reduction in the locomotor activity (at 1 and 3 days), associated with an increased activation of satellite glial cells in the ipsilateral trigeminal ganglion (TG; for up to 8 days). Amygdala astrocyte activation was unaffected in any experimental groups. We provide novel evidence indicating that CFA-induced pulp inflammation impaired the locomotor activity, with persistent activation of ipsilateral TG satellite cells surrounding sensory neurons, without any evidence of systemic inflammation or amygdala astrogliosis.

Effects of the nitric oxide releasing biomimetic nanomatrix gel on pulp-dentin regeneration: Pilot study.

Successful disinfection alongside complete endodontic tissue regeneration and revascularization are the most desired clinical outcomes of regenerative endodontics. Despite reported clinical successes, significant limitations to the current regenerative endodontic procedure (REP) have been elucidated. To improve the current REP, an antibiotics and nitric oxide (NO) releasing biomimetic nanomatrix gel was developed. The study evaluates antibacterial effects of an antibiotics and NO releasing biomimetic nanomatrix gel on multispecies endodontic bacteria. Antibiotics, ciprofloxacin (CF) and metronidazole (MN) were mixed and encapsulated within the NO releasing biomimetic nanomatrix gel. The gel was synthesized and self-assembled from peptide amphiphiles containing various functional groups. Antibacterial effects of the antibiotics and NO releasing biomimetic nanomatrix gel were evaluated using bacterial viability assays involving endodontic microorganisms including clinical samples. Pulp-dentin regeneration was evaluated via animal-model experiments. The antibiotics and NO releasing biomimetic nanomatrix gel demonstrated a concentration dependent antibacterial effect. In addition, NO alone demonstrated a concentration dependent antibacterial effect on endodontic microorganism. An in vivo analysis demonstrated the antibiotics and NO releasing biomimetic nanomatrix gel promoted tooth revascularization with maturation of root canals. An optimal concentration of and NO releasing nanomatrix gel is suggested for its potential as a root treatment material for REP and an appropriate protocol for human trials. Further investigation is required to obtain a larger sample size and decide upon ideal growth factor incorporation.

Regenerative endodontics after front tooth trauma. A case report / Regenerative endodontische Therapie nach Frontzahntrauma. Ein Fallbericht

In the context of tooth trauma, mostly the maxillary central front teeth are involved, whereby their roots are in some cases still in the developing stage (immature). Depending on the type of trauma, a necrosis of the pulp is the consequence or at least foreseeable. In order to preserve such a tooth, an endodontic therapy is inevitable. The disadvantage of conventional endodontic therapy methods of immature teeth (apexification, apexogenesis) is the root growth stop. Alternatively, the regeneration/revascularisation of the dental pulp (RP) was suggested, that allows a further root growth. The aim of this case report is to present the procedure of a RP-therapy and to suggest a step-by-step manual.

Role of medullary astroglial glutamine synthesis in tooth pulp hypersensitivity associated with frequent masseter muscle contraction.

Background The mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle hyperalgesia remain largely underinvestigated. In the present study, we aimed to determine whether masseter muscle contraction induced by daily electrical stimulation influences the mechanical head-withdrawal threshold and genioglossus electromyography activity caused by the application of capsaicin to the upper first molar tooth pulp. We further investigated whether astroglial glutamine synthesis is involved in first molar tooth pulp hypersensitivity associated with masseter muscle contraction. Methods The first molar tooth pulp was treated with capsaicin or vehicle in masseter muscle contraction or sham rats, following which the astroglial glutamine synthetase inhibitor methionine sulfoximine or Phosphate buffered saline (PBS) was applied. Astroglial activation was assessed via immunohistochemistry. Results The mechanical head-withdrawal threshold of the ipsilateral masseter muscle was significantly decreased in masseter muscle contraction rats than in sham rats. Genioglossus electromyography activity was significantly higher in masseter muscle contraction rats than sham rats. Glial fibrillary acidic protein-immunoreactive cell density was significantly higher in masseter muscle contraction rats than in sham rats. Administration of methionine sulfoximine induced no significant changes in the density of glial fibrillary acidic protein-immunoreactive cells relative to PBS treatment. However, mechanical head-withdrawal threshold was significantly higher in masseter muscle contraction rats than PBS-treated rats after methionine sulfoximine administration. Genioglossus electromyography activity following first molar tooth pulp capsaicin treatment was significantly lower in methionine sulfoximine-treated rats than in PBS-treated rats. In the ipsilateral region, the total number of phosphorylated extracellular signal-regulated protein kinase immunoreactive cells in the medullary dorsal horn was significantly smaller upon first molar tooth pulp capsaicin application in methionine sulfoximine-treated rats than in PBS-treated rats. Conclusions Our results suggest that masseter muscle contraction induces astroglial activation, and that this activation spreads from caudal to the obex in the medullary dorsal horn, resulting in enhanced neuronal excitability associated with astroglial glutamine synthesis in medullary dorsal horn neurons receiving inputs from the tooth pulp. These findings provide significant insight into the mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle contraction.

Long-term Prognosis of Pulpal Status of Traumatized Teeth Exhibiting Contradictory Results between Pulp Sensibility Test and Ultrasound Doppler Flowmetry: A Retrospective Study.

INTRODUCTION: In this retrospective study, we investigated long-term (over 3 years) follow-up results of teeth that exhibited contradictory results between the pulp sensibility test (thermal or electric pulp test) and ultrasound Doppler flowmetry (UDF) until 1 year after trauma to inspect the prognosis of the pulp. METHODS: Data were collected from the records of trauma patients in our hospital between February 2012 and May 2015. The teeth that had continuously shown contrasting results on the pulp sensibility test and UDF until 1 year after trauma were chosen for the study. Cases with follow-up records of more than 3 years after trauma were finally included, and a retrospective chart review was performed. RESULTS: Data from 343 teeth in 147 patients who visited the hospital with traumatic dental injuries were examined. Among these, 13 teeth from 7 patients were included, and the record of each case was reviewed. All the subjects showed negative responses on the pulp sensibility test and positive responses on UDF until 1 year after trauma. Ultimately, 8 of the 13 teeth recovered pulp sensibility. Two teeth failed to recover pulp sensibility and became symptomatic; root canal treatment was performed on the teeth. The remaining 3 teeth belonged to patients suffering from nerve damage; therefore, the pulp sensibility test was not feasible. CONCLUSIONS: Based on this study, UDF can be effectively used for the evaluation of pulpal status in traumatized teeth.

Dental properties, ultrastructure, and pulp cells associated with a novel DSPP mutation.

OBJECTIVE: To investigate physical characteristics and behaviours of dental pulp cells of teeth isolated from a dentinogenesis imperfecta (DGI) patient with a novel dentin sialophosphoprotein (DSPP) mutation. SUBJECTS AND METHODS: Whole exome and Sanger sequencing were employed to identify mutations. Physical characteristics of the teeth were examined. Pulp cells' behaviours including cell proliferation, colony-forming unit, osteogenic differentiation, pluripotent markers, and mesenchymal stem cell markers were investigated. RESULTS: The proband had opalescent brown primary teeth with extensive loss of enamel. Mutation analysis revealed a novel heterozygous 4-bp deletion, c.1915_1918delAAGT (p.K639QfsX674), in exon 5 of the DSPP associated with DGI. Analysis of the extracted primary incisor demonstrated a decrease in brightness but an increase in yellow and red chroma. The dentin showed reduced mineral density. The dentinal tubules were present in the predentin, but progressively collapsed in the dentin. The pulp cells exhibited markedly reduced CD105 expression, decreased cell proliferation, and smaller colony-forming units. CONCLUSIONS: We identified a novel mutation in the DSPP gene which disturbed dentin characteristics and pulp cells' behaviours. Our study expands the mutation spectrum and understanding of pathologic dentin phenotypes related to the frameshift deletion in the dentin phosphoprotein (DPP) region of the DSPP gene.

Expression of factors involved in dental pulp physiopathological processes by nemotic human pulpal fibroblasts.

AIM: To investigate in human dental pulp fibroblasts (HDPF) the expression of factors involved in dental pulp physiopathological processes and in an experimental model of cell activation called nemosis, and to compare the behaviour of pulp cell activation with sound lung fibroblast MRC5, employed as a reference model for nemosis. METHODOLOGY: Nemotic response was induced in three-dimensional cultures of HDPF and lung fibroblasts. The expressions of molecules involved in physiological (alkaline phosphatase, type I collagen) and in inflammatory processes (IL-6, CXCL8, CCL20, COX-2) were studied using real-time PCR. Concentrations of IL-6 and CXCL8 were analysed during 4 days with ELISA. Nonparametric tests were used to determine statistical differences between groups. RESULTS: A significant decrease (P < 0.001) in type I collagen and alkaline phosphatase was observed in MRC5 and HDPF nemotic responses. Although the amounts of mRNA differed between these cell types, there was an increase in CCL20, CXCL8 and COX-2 expression (P < 0.001). Unlike HDPF, MRC5 spheroids displayed significant amounts of IL-6 concentrations and mRNA expression. Notably, increased concentrations of CXCL8 were recorded in all three-dimensional cultures compared with monolayers as a function of time (P < 0.05). CONCLUSION: Although the nemotic responses observed were not identical in the pulpal and lung fibroblasts, similarities occurred in the expression of chemokines and cyclooxygenase-2. Nemotic reactions and inflammatory processes in pulp diseases share similarities in terms of the expression of factors. Thus, this in vitro model could constitute a powerful tool to study intercellular relations within the dental pulp and to develop new local treatments to counteract the inflammatory reaction that occurs during pulpitis.

Ultrasound Enhances Dentoalveolar Remodeling in an Ex Vivo Orthodontic, Ovariectomy-Induced Osteoporotic Model.

The aim of the study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on dentoalveolar structures during application of force to a cultured mandible slice taken from an ovariectomized rat model of osteoporosis. Rats were divided based on whether they had ovariectomy and/or LIPUS application into four groups: control osteoporosis group, control normal group, ultrasound-treated osteoporosis group and ultrasound-treated normal group. The mandibles were dissected, sliced and cultured before application of a 0.5-N force. Tissue specimens from five rats per group received LIPUS; the remaining rats served as untreated controls. Tissue sections were evaluated histologically and histomorphometrically. Osteoporosis significantly affected the alveolar bone without any effect on the dentin-pulp complex. LIPUS enhanced osteoporotic alveolar bone remodeling and increased cementum and predentin thickness. Furthermore, LIPUS application significantly increased odontoblast and periodontal ligament cell counts (p < 0.05) in both groups. Therefore, LIPUS enhances alveolar bone remolding and increases cementum and predentin formation in osteoporotic rat mandible slice organ cultures.

Age-related morphological, histological and functional changes in teeth.

Throughout lifetime, the teeth are continuously exposed to numerous chemical and physical impacts, which cause the wear of the dental hard tissues, gingival recession and other oral changes with sometimes subsequent problems. Age-related wear of tooth surfaces reduces the dental enamel thickness and exposes deeper layers of enamel, which have different physical and chemical properties than the surface enamel. Gingival recession is the main causal factor of root caries and dentine hypersensitivity. Age-related changes in dentine include the formation of secondary dentine and the reduction in tubular lumen diameter (dentine sclerosis), which lead to a reduction in the volume of the pulp chamber. In addition to the reduction in the volume of pulp chamber, changes to the dental pulp also include dental pulp calcifications. The age-related physiological changes to the teeth should be carefully distinguished from pathological changes, especially when they induce pain or a negative impact on the oral health-related quality of life (OHRQoL) of the older individuals. Therefore, regular oral examinations coupled with early preventive measures should aim at maintaining oral health until old age.

Predicting pre- and postoperative pain of endodontic origin in a southern Brazilian subpopulation: an electronic database study.

AIM: To determine the prevalence of preoperative endodontic pain (PREP) and the incidence of postoperative endodontic pain (POEP), identifying the predictors of PREP and POEP in a southern Brazilian subpopulation, using clinical data from an electronic chart database (ECD). METHODOLOGY: This retrospective observational study included 563 consecutive individuals presenting for root canal treatment (RCT). Patients were treated by undergraduate and graduate students, following standard RCT protocols. Demographic, medical and dental variables were extracted from a pre-structured and standardized ECD. The main outcomes PREP and incident POEP were collected through a 0-10 numeric rating scale, dichotomized as none/mild (<4) or moderate/severe (≥4) pain. Predictive models calculating the prevalence ratios (PR) of PREP and the relative risks (RR) of incident POEP were carried out with Poisson regression analysis, estimating the relationship between clinical factors, PREP and incident POEP. RESULTS: Mean age at baseline was 49.2 ± 17.1 years, with 68.4% women. The prevalence and incidence of moderate/severe PREP and POEP were 44.4% and 3.8%, respectively. RCT intervention significantly reduced PREP (P < 0.001). Multivariate analysis revealed that group of teeth, location (mandibular teeth), pulpitis, necrotic pulp, preoperative swelling and periapical radiolucency were independently associated with moderate/severe PREP, whilst age ≥60 years and root canal retreatments were independent protective factors to PREP (P < 0.05). No demographic, medical or dental variables were associated with POEP, although molar teeth (RR = 4.23, 95%CI = 0.93-19.2, P = 0.056) had a borderline nonsignificant association. CONCLUSIONS: Moderate/severe PREP was independently associated with age, group of teeth, location, preoperative swelling, retreatments and pulp and periapical status. No demographic, medical or dental variable predicted moderate/severe POEP following RCT amongst this subpopulation.