Histological study of platelet-rich fibrin combined with MTA for direct pulp capping of rabbit teeth / 口腔疾病防治

Objective @# To investigate the outcomes of a novel direct pulp capping agent containing platelet-rich fibrin (PRF) and mineral trioxide aggregate (MTA). @*Methods @# A total of 32 New Zealand rabbits were randomly divided into 4 groups, namely, the PRF+MTA group (P+M group), PRF group (P group), MTA group (M group) and blank control group (BC group), with 8 rabbits per group. Dental pulp exposure and direct pulp capping were performed, and complete crown square sealing was performed on 2 mandibular central incisor teeth of each rabbit. Four rabbits from each group were euthanized after each observation period (7 and 28 days). The experimental teeth were subjected to HE staining. Inflammatory cell infiltration, calcified bridge formation and pulp tissue disorganization were observed and graded. @*Results@#Inflammatory cell infiltration: on the 7th day, group P+M and group M were lighter than group BC (P<0.05); on the 28th day, group P+M was lighter than group P and group BC (P<0.05); group P+M and group M did not significantly differ (P>0.05). Calcified bridge formation: on the 7th and 28th days, group P+M was lighter than group P, group M and group BC (P<0.05); on the 28th day, group M was higher than group BC (P<0.05). Under microscope, the calcified bridge contained cellular components and was surrounded by odontoblast-like cells, sharing a structure resembled osteodentin; dentin tubule-like structure could not be observed in calcified bridge, and the calcified bridge resembled certain points of osteodentin. Pulp tissue disorganization: on the 7th day, group P+M and group M were lighter than group BC (P<0.05); on the 28th day, group P+M was lighter than group P and group BC (P<0.05). group P+M and group M did not significantly differ (P>0.05). @*Conclusion @# The combination of PRF and MTA for direct pulp capping provided light inflammatory cell infiltration, stable pulp status and a strong ability of pulp tissue to form calcified bridge, and the calcified bridge resembled certain points of osteodentin.

Root morphology and number of canals in mandibular central and lateral incisors using cone beam computed tomography

Abstract Most failures in endodontic treatment of mandibular incisors are due to the presence of a missed canal specifically the lingual. This investigation aimed to examine the root morphology and number of canals in mandibular incisors using cone beam computed tomography (CBCT). Two hundred and seven patients were assessed in terms of their mandibular central and lateral incisors of CBCT. The inclusion criteria were absence of root resorption, coronal restoration or root filling and clarity and optimal resolution of images. According to the Vertucci's classification, number of roots and canals and type of canal were evaluated by two oral and maxillofacial radiologists. In order to data analysis SPSS version 16 and descriptive statistics were implemented. All mandibular incisors had one root. Most central (84.5%) and lateral (78.2%) incisors had a single canal (p= 0.065). The majority of central (54.5%) and lateral (56.5%) incisors were Vertucci's type I (p= 0.102). Prevalence of one canal in males: central (84.8%), lateral (77.9%) and in females: central (84.2%), lateral (78.5%) (p= 0.518). Prevalence of Vertucci's type I in males: central (52.3%), lateral (45.3%) and in females: central (56.1%), lateral (64.4%) (p=0.188). The prevalence of two canals was 15.5% (central) and 21.8% (lateral) in mandibular incisors. The Vertucci's type I was the most typical kinds of mandibular incisors. Considering the limitations of periapical radiography in determining canal morphology, CBCT can be helpful in case of any concern regarding root canal morphology.

Resumo A maioria das falhas no tratamento endodôntico dos incisivos mandibulares é devida à presença de um canal perdido, especificamente do lingual. Esta investigação teve como objetivo analisar a morfologia radicular e o número de canais nos incisivos inferiores utilizando a tomografia computadorizada de feixe cônico (TCFC). Duzentos e sete pacientes foram avaliados em termos de seus incisivos centrais e laterais mandibulares de TCFC. Os critérios de inclusão foram ausência de reabsorção radicular, restauração coronária ou preenchimento radicular e clareza e resolução ótima das imagens. De acordo com a classificação de Vertucci, o número de raízes e canais e o tipo de canal foram avaliados por dois radiologistas orais e maxilo-faciais. Para análise dos dados, o SPSS versão 16 e análise estatística descritiva foram implementados. Todos os incisivos inferiores tinham uma raiz. A maioria dos incisivos centrais (84,5%) e laterais (78,2%) apresentava um único canal (valor de P: 0,065). A maioria dos incisivos centrais (54,5%) e laterais (56,5%) eram do tipo I de Vertucci (valor de P: 0,102). Prevalência de um canal no sexo masculino: central (84,8%), lateral (77,9%) e no feminino: central (84,2%), lateral (78,5%) (valor de P: 0,518). Prevalência de Vertucci tipo I em homens: central (52,3%), lateral (45,3%) e feminina: central (56,1%), lateral (64,4%) (valor de P: 0,188). A prevalência de dois canais foi de 15,5% (central) e 21,8% (lateral) nos incisivos inferiores. O tipo I de Vertucci era dos tipos mais comuns de incisivos inferiores. Considerando as limitações da radiografia periapical na determinação da morfologia do canal, a TCFC pode ser útil em caso de qualquer preocupação com relação à morfologia do canal radicular.

Mandibular talon cusp - a case report

Talon cusp is a relatively rare developmental dental anomaly, characterized by cusp-like projections from the cingulum area, or cemento-enamel junction of maxillary or mandibular anterior teeth, in both the primary and permanent dentition. In most of the cases it involves maxillary lateral incisors. The anomaly has been reported to be rare especially when it occurs on mandibular teeth. This article reports a case of talon cusp on permanent mandibular central incisor, which makes it a rare entity.

Dental gemination in a permanent mandibular central incisor: an uncommon dental anomaly / Geminación dental en un incisivo central mandibular permanente: una anomalía dental infrecuente

Gemination is an anomaly in size, shape, and structure of the teeth. The primary dentition is more frequently affected, but gemination may occur in permanent dentitions, usually in the maxillary-incisal region. In geminated teeth, incomplete development of two teeth from a single bud results in a larger tooth crown with a single root and canal. In this study, a gemination case in a male patient, 13-year-old, with an ancestry of Aymara, who visited a private clinic in Antofagasta, Chile, for a routine check is presented. On intra-oral clinical examination of the coronary anatomy, the tooth 4.1 was observed with a large crown, bifurcated in the center of incisal zone. In addition, a groove extending from the bifurcation to the cementoenamel junction was noted. Radiographic examination revealed the presence of a single root canal and a single root. The pulp cavity was separated in two cavities, in accordance with the division caused by the observed bifurcation. This report describes a unique case of dental gemination of mandibular permanent central incisor in a subject with Aymara ancestry and discusses the differential diagnosis and possible future treatment options anticipated for this particular case.

La geminación es una anomalía que afecta el tamaño, forma y estructura del diente. La dentición temporal es afectada con más frecuencia, pero puede ocurrir en la dentición permanente, generalmente en la región maxilar incisal. En los dientes geminados, el desarrollo incompleto de dos dientes desde un solo brote dentario resulta en una corona dentaria más grande, con una sola raíz y canal. En este artículo, se presenta un caso de geminación en un paciente de sexo masculino, de 13 años de edad con ascendencia Aymara observada durante un control de rutina. Al examen clínico intraoral, el diente 41 se observó con una gran corona, bifurcado en el centro de la zona incisal, junto a un surco que se extendió desde la bifurcación hasta la unión amelo-cementaria. El examen radiográfico reveló la presencia de una sola raíz y un canal único. La cavidad pulpar se separó en dos, según la división causada por la bifurcación coronaria. Este reporte muestra un caso infrecuente de geminación dental del incisivo central mandibular permanente en un sujeto de ascendencia Aymara, y se discute su diagnóstico diferencial y las opciones de tratamiento futuras previstas para este caso en particular.

A Cephalometric Study to Determine The Inclination And Position of Mandibular Incisor Teeth In Dentures And Natural Dentition.

Many dentures do not satisfy the esthetic values the patient deserves. One of the chief error occurs in the placement of anterior teeth. Failure to place anterior teeth in their correct position may cause altered facial appearance, expression and faulty facial contours. In this study an attempt was made to determine by means of a cephalometric analysis, the extent to which artificial mandibular anterior teeth arranged for complete denture, approximate the natural teeth mean values as obtained from adult dentulous subjects