Raíces dentales humanas normales y con perlas de cemento: comparación histológica de estructuras / Normal human dental roots and withcementum pearls: structural histological comparison

Durante la vida del diente en boca se deposita cemento celular en el ápice a fin de compensar el desgaste oclusal considerado normal. Al extraer un diente, en raras ocasiones es posible visualizar excesos de cemento con forma de perlas bien delimitados y duros al tacto, ubicados en otro sector radicular diferente al ápice. Nuestro objetivo fue comparar estructuras en ambos tipos de cemento a fin de hallar diferencias histológicas. Se utilizaron 20 dientes permanentes con perlas (G1) y 20 con raíces normales (G2). Las raíces de G1 se cortaron con disco metálico de grano fino a baja velocidad en sentido transversal, a la altura de la parte más prominente de la protuberancia, las raíces de G2 se marcaron en tercios y se cortaron en sentido transversal aproximadamente a la altura de la mitad del tercio apical y de ambos grupos se obtuvieron un segmento que fue reservado y otro que fue preparado con técnica por desgaste para visualización con MO a menor y mayor aumentos. Los resultados se compararon con prueba t de student, las variables categóricas se compararon con pruebas de Fisher significación 5 por ciento. Se obtuvieron 40 dientes de pacientes adultos, 42,5 por ciento masculinos y 57,5 por ciento femeninos, edad promedio 61+/-16 en G1 y 55+/-18 en G2 (p=0,289). El contorno exterior de las perlas fue liso, conservando su perímetro, la zona granular de Tomes fue visible al igual que las lagunas, que fueron menos abundantes, de mayor tamaño y con distribución desordenada llegando en menor proporción al borde del tejido comparado con cemento normal.

During tooth life in mouth cellular cement settles in the apex in order to compensate the occlusal wear considered normal. After a tooth extraction, on rare occasions it is possible to visualize cement excesses with pearls form well delimited and hard to tact, located in another radicular sector different of the apex. Our aim was to compare structures in both types of cement in order to find histological differences. Consequently, 20 permanent teeth with pearls (G1) and 20 with normal roots (G2) were used. G1 roots were cut by a thin grain metallic disc at low speed in transverse sense, at the height of the protuberance most prominent part; G2 roots were marked in thirds and cut in transverse sense at the half of the third apical. From both groups a segment was obtained to be reserved and other one that was prepared by erosion technology to be visualized by MO at minor and major increases. Results were compared with student t test, categorical variables with Fisher's tests significance 5 percent. Forty adult patients teeth were obtained, male 42.5 percent and female 57.5 percent, age average in G1 61+/-16 and 55+/-18 in G2 (p=0.289). Pearls exterior face was smooth, with a preserved perimeter, Tomes granular zone was visible as were lagoons, which were less abundant, greater in size and with uneven distribution arriving at tissue border in a lesser proportion compared with normal cement.

Hipercementosis apicales y no apicales en raíces dentarias humanas / Apical and non-apical hypercementosis in human dental root

El cemento secundario del ápice radicular se deposita en forma lenta y continua durante toda la vida útil del diente, siendo su función compensar el desgaste producido por la masticación. En raras ocasiones podemos hallar en la raíz dental, a posteriori de una extracción dentaria, excesos de cementos redondeados u ovalados, bien delimitados y duros al tacto, ubicados en un sector radicular diferente al ápice. Nuestro objetivo fue comparar las características físicas y radiológicas de raíces dentales normales con aquéllas que presentan este tipo de formaciones que alteran la anatomía radicular. Fueron incluidos 20 dientes adultos con raíces normales y 20 con raíces donde se visualizaron estos depósitos. Las variables investigadas fueron edad, sexo, patologías generales y periodontales previas, tipo de diente extraído, ubicación en el arco dental, motivo de extracción, características de consistencia, color, aspecto y textura de todas las raíces. La imagen radiológica fue crucial para la inclusión de dientes con exceso de cemento. Se recolectó un total de 40 dientes adultos, cuya edad promedio fue de 61 años (16-79), 42.5 por ciento masculinos y 57.5 por ciento femeninos. Patología general presentó el 37.5 por ciento y periodontal el 55 por ciento, los dientes mas extraídos fueron premolares superiores del lado derecho 15 por ciento. La caries fue causa principal de extracción 72.5 por ciento. En ambos grupos las raíces fueron de consistencia dura y textura lisa. El aspecto nacarado fue de 70 por ciento y 60 por ciento, los colores claros 45 por ciento y 75 por ciento, respectivamente. En las radiografías se observó que el cemento no se diferenció de la dentina en el 40 por ciento y 85 por ciento de cada grupo (p=0.004). Los adultos pueden desarrollar anomalías de cemento ubicadas en otro sector del ápice si bien las características físicas de la raíz se consideran dentro de parámetros normales.

Secondary cementum is deposited in a root apical third throughout the lifespan of a tooth to compensate occlusal erosion, keeping dental pieces in occlusion contact. Pearls are more difficult to spot, found by X-rays or after extraction. Their ovoid or spherical aspect is well outlined, hard to touch, and located in different thirds of the root. Our objective was to compare physical and radiological dental normal roots characteristics with those presenting this type of formations that alter radicular anatomy. We used 20 normal roots and 20 pearl shapes. Variables compared: age, sex, previous general pathologies and periodontals; extracted tooth type, dental arch location, extraction cause, consistency characteristics, color, aspect and texture of all roots and pearls. Radiological image was crucial for incorporation of teeth with cementum excess. Proportions between normal pieces and pearls were calculated with Fisher's Exact Test, with 5 percent significance level. Average age was 61years (16-79), and male proportion was 42.5 percent and 57.5 percent female. General pathology presented 37.5 percent and periodontal 55 percent, more extracted teeth were right side upper premolars 15 percent. Caries were extraction chief motive 72.5 percent. Roots were of hard consistency and smooth texture in both groups; nacreous aspect was 65 percent, clear colors 75 percent. Pearl consistency was hard in all of them; white color 60 percent and root similar color 40 percent; nacreous aspect 75 percent and smooth texture 90 percent. In radiographs was observed that cementum did not differ from dentine in 85 percent of pearls and in 60 percent of normal roots (p=0.004). Adults can develop cementum anomalies located in another apex sector although the root physical characteristics are considered inside normal parameters.

A scanning electron microscopic study of hypercementosis

The purpose of this study was to evaluate morphological characteristics of teeth with hypercementosis that are relevant to endodontic practice. Twenty-eight extracted teeth with hypercementosis had their root apexes analyzed by scanning electron microscopy (SEM). The teeth were divided according to tooth groups and type of hypercementosis. The following aspects were examined under SEM: the contour and regularity of the root surface; presence of resorption; presence and number of apical foramina, and the diameter of the main foramen. The progression of club shape hypercementosis was directly associated with the presence of foramina and apical foramen obstruction. Cases of focal hypercementosis presented foramina on the surface, even when sidelong located in the root. Circular cementum hyperplasia form was present in 2 out of 3 residual roots, which was the highest proportion among the tooth types. The detection of a large number of foramina in the apical third of teeth with hypercementosis or even the possible existence of apical foramen obliteration contributes to understand the difficulties faced during endodontic treatment of these cases.

Estudos macro e microscópico da morfologia do terço dentário apical na hipercementose: implicaçöes clínicas e etiopatogênicas / Macro and microscopical studies of apical dental portion morphology in the hypercementosis: clinical and etiopathogenic implications

Cento e sessenta dentes com e sem hipercementose foram analisados macroscopicamente, ao estereomicroscópio sem e com diafanizaçäo e na microscopia óptica de luz, com a finalidade de estudar a anatomia externa e interna do terço apical. Verificou-se que: 1) A hipercementose aumenta consideravelmente o número de canais secundários, canais acessórios e deltas apicais. 2) As modificaçöes na morfologia interna do terço apical dos dentes comprometidos näo säo passíveis de visualizaçäo e identificaçäo radiográfica. 3) O canal principal na grande maioria dos dentes com hipercementose apresenta-se constricto no terço apical associado à mudança da trajetória original ou a canais secundários, acessórios e deltas apicais. 4) O tipo morfológico mais comum de hipercementose dá à raiz a forma de clava. A forma localizada de hipercementose apresenta-se com considerável menor frequência. A forma de boca de manga de camisa encontra-se apenas eventualmente. 5) O padräo morfológico e aposicional do cemento constituinte da hipercementose assemelha-se ao cemento em dentes normais quando observado na microscopia óptica de luz, assim como sua superfície externa. Após estas verificaçöes, concluiu-se que na hipercementose o clínico de várias especialidades, como o cirurgiäo, o ortodontista e especialmente o endodontista, deve considerar a modificaçäo anatômica externa e interna a que foi submetido o dente portador, pois sua forma radicular tende a ser retentiva, o corpo radicular mais espesso e o terço apical mais rico em canalículos e deltas apicais associado à constricçäo e mudança direcional do canal principal