Frequency of pulp canal obliteration in primary teeth after traumatic dental injury and its association with related variables / Frequência de obliteração do canal pulpar nos dentes decíduos após traumatismo dentário e sua associação com variáveis relacionadas

ABSTRACT Objective The aim of this study was to determine the frequency of pulp canal obliteration (PCO) after traumatic dental injury (TDI) of primary anterior teeth and to investigate its relation with the related variables. Methods This retrospective study has been done with dental records of patients selected from the Paediatric Dental Trauma Clinic between 2006 and 2016. Those who had PCO in the primary anterior teeth and were aged 0-108 months at the time of trauma were considered eligible. Data related to patients and TDI, such as sex, the child's age at the time of trauma, aetiology, affected teeth, the child's age at the time of the eruption of the permanent successor as well as the presence of crown discoloration were extracted from the dental records. Results Among the 483 children with traumatised teeth, 14.9% had PCO and the most of them exhibited crown discoloration. The average age of the children at the time of the trauma was 38 months and the most common aetiology of the TDI was falls. The average time for the beginning of the PCO process was 13.5 months. There was no statistically significant association between the child's age at the time of trauma and the types of TDI, PCO and the presence of crown discoloration. Conclusions The frequency of PCO was relatively low though the presence of crown discoloration was considerable. There was no association between the child's age at the time of trauma and the studied variable.

RESUMO Objetivo O objetivo desse estudo foi determinar a frequência de obliteração do canal pulpar (OCP) após traumatismo dos dentes decíduos anteriores e investigar sua associação com variáveis relacionadas. Métodos Este estudo retrospectivo foi realizado com base nos prontuários odontológicos de pacientes selecionados da Clínica de Trauma Dentário Pediátrico entre 2006 e 2016. Aqueles que tinham OCP nos dentes decíduos anteriores e tinham entre 0-108 meses no momento do traumatismo foram considerados elegíveis. Dados dos pacientes e dos traumatismos, tais como, sexo, idade da criança no momento do traumatismo, etiologia, dente afetado, idade da criança na época no momento da erupção do sucessor permanente, bem como presença de alteração de cor da coroa foram extraídos dos prontuários. Resultados Dentre as 483 crianças com dentes com traumatismos, 14.9% tinham OCP e a maioria delas apresentava alteração de cor da coroa. A média de idade da criança no momento do traumatismo foi de 38 meses e a etiologia mais comumente associada ao TD foram as quedas. O tempo médio decorrido para o início do processo de OCP foi de 13,5 meses. Não houve associação estatisticamente significativa entre a idade da criança no momento do traumatismo e os tipos de TD, OCP e presença de alteração de cor da coroa. Conclusão A frequência de OCP foi relativamente baixa, embora a presença de alteração da coroa tenha sido considerável. Não foi encontrada associação entre a idade da criança no momento do trauma e as variáveis estudadas.

Assessment of Dental Caries and Intervention in the First Permanent Molars of Brazilian Children

ABSTRACT Objective: To evaluate the prevalence of caries stages and interventions on first permanent molars (FPM) in Brazilian children. Material and Methods: Data from FPM were extracted from dental records of children aged 5-14 years of age that attended the UERJ Pediatric Dentistry Clinic. Data include patient age, sex, biofilm index, presence of carious lesions in all stages, and the treatments. Data was analyzed using the SPSS® 20.0 program. Results: A total of 158 dental records were analyzed, 587 registers were related to the caries stage and 601 related to the interventions; mean age of 8.26 (±1.4 years) and 53.2% were girls. The prevalence of active/inactive white spot(AWS/IWS) varied from 14.3% to 21.6% in right upper and lower left FPM, respectively. Enamel/dentin lesions without pulp involvement were also more prevalent in the lower arch and ranged from 3.4% for the right upper to 11.5% for the lower right FPM. Cavities with pulp involvement or indicated extraction ranged from 0% to 1.4%. Treatment included dental sealants, varying from 17.1 to 24.0% (n=126) and restorations, varying from 1.3 to 11.8% (n=38). The lower right were the most affected teeth. Conclusion: First permanent molars presented a higher prevalence of dental caries in early stages and the most prevalent treatment was related to the initial carious process, fluor therapy and sealants.

Assesment of artificial caries lesions through scanning electron microscopy and cross-sectional microhardness test.

Aims: To assess through scanning electron microscopy (SEM) and cross-sectional microhardness (CSMH) test whether the methodology exposed in this experiment can be used to produce artificial active white spot lesions (AAWSLs) on smooth unabraded human dental enamel. Materials and Methods: Ten human permanent molars were used in this experiment. One section of each tooth was double coated with nail varnish except for a limited central area sized 2.5 mm × 1 mm (2.5 mm 2 ). Each specimen was individually exposed to 10.4 ml of a demineralizing solution at pH 5.0, during 42 days (37°C) without agitation. Samples were sectioned in the center of the AAWSL and one half was analyzed in SEM and the other half was subjected to CSMH. Descriptive statistics was performed to determine mean depth of the lesion. Results: The mean depth of AAWSL was 100 μm (s.d. =12.1) and a white dull rough surface could be detected by the unaided eye. SEM images demonstrated that although some surface areas of the lesion appeared to be relatively intact, erosion was present. A prismatic pattern of dissolution was observed in all samples with an enlargement of the prism sheaths and some samples had also sites of destruction of prism cores. Conclusion: This methodology can be used to induce AAWSLs in human dental enamel but surface erosion has to be taken into account when performing CSMH test.

Contaminação salivar e o recondicionamento ácido de esmalte dental humano / Salivary contamination and reconditioning of human dental enamel

Objetivo: Avaliar, ao microscópio eletrônico de varredura, a micromorfologia do esmalte dentário decíduo e permanente condicionado com ácido fosfórico a 37%, contaminado por saliva humana e recondicionado por 10 segundos. Métodos: Dois grupos, decíduo e permanente, compostos por cinco incisivos humanos cada, originaram treze superfícies vestibulares onde: dez foram condicionadas com ácido fosfórico (15s e 30s), duas foram apenas contaminadas por saliva (5s e 30s) e uma permaneceu sem condicionamento. Das dez amostras condicionadas, oito foram contaminadas com saliva (5s e 30 s) e apenas quatro foram recondicionadas. Resultados: Os padrões de condicionamento ácido com 15s ou 30s não produziram diferenças visíveis no esmalte de dentes decíduos e permanentes, embora o tempo de 30s produziu uma desmineralização mais profunda no esmalte dos permanentes. A contaminação salivar por 5s e 30s obstruiu as microporosidades produzidas pelo condicionamento ácido, e a lavagem subsequente (30s) não foi suficiente para eliminação desta obstrução. Conclusão: As imagens obtidas ao microscópio eletrônico de varredura sugerem que o recondicionamento ácido do esmalte dentário por 10s produziu uma micromorfologia adequada nas amostras condicionadas durante 15s e contaminadas com saliva por 5s, em ambos os grupos.

Objective: Evaluate the morphology of deciduous and permanent human enamel using a scanning electron microscope (SEM) to analyze it after acid etching with 37% phosphoric acid, human saliva contamination and reconditioning for 10 seconds (s). Methods: Two groups, deciduous and permanent, consisting of five human incisive teeth each, originated thirteen vestibular surfaces where 10 were etched with phosphoric acid (15s and 30s), two were only contaminated with saliva (5s and 30s) and one remained unetched. Eight of the ten etched specimens were contaminated with human saliva (5s and 30s) and only four were reconditioned. Results: The patterns observed with 15s and 30s of acid etching did not produce visible changes on the deciduous or permanent human dental enamel but thirty seconds of acid etching produced a deeper demineralization on the enamel of permanent teeth. Salivary contamination for 5s and 30s obstructed the micropores produced by acid etching and rinsing with water for 30s was not enough to remove it. Conclusion: According to the images obtained by a scanning electron microscope, reconditioning of the enamel for 10s can produce adequate micropores in samples etched for 15s and contaminated with saliva for 5s in both test groups.

Alterações na amelogênese e suas implicações clínicas: relatos de casos / Alterations in amelogenesis and its clinical implications: cases reports

Alterações durante a amelogênese podem acarretar distúrbios no desenvolvimento do esmalte dentário. Em consequência a estas alterações o esmalte dentário pode apresentar modificação de cor e/ou que podem ocorrer isoladamente ou de forma simultânea, envolvendo, apenas um ou mais dentes. A intensidade, a extensão e a quantidade de elementos dentários envolvidos pelas alterações no esmalte podem estar relacionadas ao estágio de desenvolvimento do órgão do esmalte dentário. As causas podem ser de origem local, sistêmica, genética ou idiopática. Após a constatação de uma alteração da amelogênese evidenciada por meio da modificação de cor e/ou estrutura do esmalte dentário pelo dentista é importante que haja um diagnóstico preciso para se proceder à terapêutica adequada, seja ela preventiva, interceptativa ou o acompanhamento clínico do caso. Os casos clínicos relatados neste estudo ilustram algumas das alterações da amelogênese no esmalte dentário humano e suas prováveis causas com base na história clínica apresentada pelo paciente e na literatura consultada.

Alterations in amelogenesis can promote disturbances on the development of dental enamel. These alterations during amelogenesis will result in different color and/or structure of dental enamel that may occur isolated or simultaneously. These alterations may involve one tooth or more, yet the causal factors may be local, systemic, genetic or idiopathic. The intensity, extension and the number of teeth presenting alterations in the dental enamel are related to the developmental stage of the enamel dental organ. After the dentist has evidenced a color and/or structural alteration due to developmental defect in amelogenesis it is very important to make a precise diagnosis so that he can proceed with an adequate therapeutic either if it is only a matter of recall appointments, preventive or interceptive approaches. The clinical cases in this study illustrates some of human dental enamel’s alterations during amelogenesis and their probable causes based on the patient’s clinical history and in the dental literature.

Effect of time in hardness test on artificially demineralized human dental enamel

A cross-sectional microhardness (CSMH) test was carried out in human dental enamel exposed to a demineralizing solution in order to evaluate two different times of indentation in sound tissue and artificially induced caries. Twenty caries-free extracted human molars had one of their smooth surfaces sectioned and the enamel surface was isolated with nail polish except for an area of 6 mm2. These specimens were submitted to artificially induced enamel caries on a lactate buffer containing 0.1 ppm fluoride (F) during 28 days. All specimens were bisected to create groups A and B in which CSMH test was performed employing a Knoop indenter with a 25 g load for 5 or 10 s, respectively. Student’s paired t-test (p<0.05) was used to determine statistically significant differences between groups A and B in 7 depths. There were no significant differences between any of the analyzed depths. Since the present experiment showed no significant difference when comparing indentations made with a 25 g load during either 5 or 10 s in different depths, this method can be used with either one of the time intervals tested without compromising a CSMH test on artificially demineralized human enamel.