Nasopalatine Duct Cyst in a 31 Year-Old Male: Imaging Findings in Computed Tomography / Quiste del Canal Nasopalatino en un Hombre de 31 años: Hallazgos en Imágenes de Tomografía Computarizada

A 31-year-old man is presented and is evaluated by panoramic radiography. As a finding, an extensive lesion with a cystic appearance was detected in the anterior part of the maxilla. Computed tomography shows a lesion corresponding to the characteristics of a cyst. In the histology the combination of two types of epithelium is observed, pseudostratified columnar and stratified squamous, confirming that this was a nasopalatine duct cyst.

Se presenta el caso de un hombre de 31 años, evaluado mediante radiografía panorámica. Como hallazgo se detecta una extensa lesión de aspecto quístico en la parte anterior del maxilar. En la tomografía computada se observa una lesión que corresponde a las carácterísticas de un quiste. La histología muestra una combinación de dos tipos de epitelio, pseudostratificado columnar y estratificado escamoso, confirmando que se trataba de un quiste del canal nasopalatino.

Evaluation of the incisive canal using cone beam computed tomography

The incisive canal is innervated by the nasopalatine nerve and irrigated by the anterior branches of the descending palatine vessels, the sphenopalatine and greater palatine artery. Sometimes, the incisor canal interferes with the placement of implants or other surgical procedures, it is necessary to resort to previous treatments in order to have the ideal conditions in the area to be treated and avoid complications. Methods: 100 cone beam computed tomography were studied evaluating the diameter, length and shape of the incisor canal, distance from the lower edge of the incisor canal to the alveolar ridge, length and width of the bone anterior to the incisor canal, and width of the palatal bone. Results and conclusions: The variables that showed a statistically significant difference comparing between male and female patients were vestibulo-palatal and incisor foramen diameter, incisor canal length, distance from the canal to the central incisor, coronal and medial width of the vestibular bone; and the width of the palatal bone at apical and mid-level; being greater in male patients.

El canal incisivo: ¿maxilar o mandibular? Revisión narrativa / The incisive canal: a maxillary or mandibular structure? Narrative review

El canal incisivo es una estructura anatómica ósea que, según la terminología anatómica actual, se encuentra ubicada exclusivamente en la premaxila. Sin embargo, a continuación de los canales mandibulares, se desprenden hacia lateral los canales mentonianos (que contiene el paquete vasculonervioso del mismo nombre) y hacia anterior continua un paquete vasculonervioso, también denominado incisivo que inerva e irriga a dichos dientes mandibulares. Con el fin de aclarar lo previamente mencionado y distinguir ambas estructuras incisivas, se pretende agregar un sufijo (maxilar o mandibular) rectificando los nombres de dichos canales. Para lo anterior, se realizó una revisión de la bibliografía disponible en PubMed y Google Académico, con las palabras clave "CANAL INCISIVO" e "INCISIVE CANAL", utilizando como operador booleano la palabra OR. Los criterios de inclusión de los estudios fueron: 1) que se refieran a algún canal incisivo (ya sea maxilar o mandibular) 2) que estén disponibles para ser leídos a texto completo y 3) que su idioma sea inglés o español. De la totalidad de los artículos analizados, un 52 % hablaba exclusivamente del canal incisivo maxilar, un 43 % solo del canal incisivo mandibular y un 5 % sobre ambos. Concluyendo, podemos colegir que es de suma importancia que se regularice la nomenclatura de dichas estructuras anatómicas, debido a que, el hecho de reconocerla como tal permite garantizar su estudio y aporte desde toda la comunidad científica, sin importar la procedencia ni el idioma. Además, el canal incisivo mandibular está bien documentado, por lo que, al no ser reconocido en la terminología anatómica, se pierde la principal misión de la asociación internacional de asociaciones de anatomía (IFAA), la cual es unificar y organizar los nombres de las estructuras anatómicas existentes.

SUMMARY: The incisive canal is an anatomical bone structure that, according to current anatomical terminology, is located exclusively in the premaxilla. However, following the mandibular canals, the mental canals (containing the neurovascular bundle of the same name) branch off laterally and a neurovascular bundle continues anteriorly, also called the incisor, which innervates and irrigates said mandibular teeth. In order to clarify what was previously mentioned and to distinguish both incisive structures, it is intended to add a suffix (maxillary or mandibular) correcting the names of said canals. For the above, a review of the literature available in PubMed and Google Scholar was carried out, with the keywords "INCISIVE CANAL" and "INCISIVE CANAL", using the word OR as a boolean operator. The inclusion criteria of the studies were: 1) that they refer to an incisive canal (whether maxillary or mandibular) 2) that they be available to be read in full text and 3) that their language be English or Spanish. Of all the articles analyzed, 52% spoke exclusively about the maxillary incisive canal, 43% only about the mandibular incisive canal, and 5% about both. In conclusion, we can infer that it is of the utmost importance that the nomenclature of these anatomical structures be regularized, because the fact of recognizing it as such allows guaranteeing its study and contribution from the entire scientific community, regardless of origin or language. In addition, the mandibular incisive canal is well documented, therefore, by not being recognized in anatomical terminology, the main mission of the international association of anatomy associations (IFAA) is lost, which is to unify and organize the names of the anatomy. existing anatomical structures.

Determinación de la morfología del canal incisivo mandibular mediante tomografía computarizada de haz cónico (CBCT) en población de Valdivia, Chile / Determination of mandibular incisor canal morphology by cone beam computed tomography (CBCT) in a population of Valdivia, Chile

RESUMEN: El canal incisivo mandibular (MIC) es un canal neural que contiene una de las ramas inferiores del nervio alveolar inferior, llamado nervio incisivo mandibular, que puede resultar dañado durante intervenciones quirúrgicas y causar complicaciones postoperatorias. Estudio descriptivo de corte transversal. Se identificó el MIC en la imagen transversal del canino en 83 hemiarcadas. Se registró edad, sexo, hemiarcada, longitudes desde reborde alveolar vestibular de canino a MIC, cortical lingual y vestibular de canino a MIC, base mandibular de canino a MIC y ubicación del MIC (tercio lingual, medio, vestibular). Medidas se registraron en milímetros. Se aplicó test T-student para muestras independientes para variables de longitud y Chi-cuadrado para ubicación espacial del MIC, en relación con grupo etario y sexo. Se evaluó el MIC en todas las muestras (100 %). El MIC fue encontrado mayormente en el tercio medio mandibular (p <0,05). La media desde el MIC a la cortical lingual es de 5,25 mm ? 1,42 mm (derecho) y 5,24 mm ? 1,18 mm (izquierdo). La media desde el MIC a la cortical vestibular fue de 4,42 mm ? 1,29 mm (derecho) y 4,53 mm ? 1,24mm (izquierdo). La media entre centro del canal y reborde alveolar vestibular fue 18,89 mm ? 2,68mm (derecho) y 18,20 mm ? 3,06 mm (izquierdo), media desde centro del MIC al margen basal fue de 9,77 mm ? 1,93 (derecho) y 10,12 mm ? 1,92 mm (izquierdo). Se encontró mayor distribución del MIC en el tercio medio mandibular. Se identificó el MIC en el 100 % de las muestras a través de CBCT por lo que su uso como examen complementario debe ser considerado al planificar cirugías en el sector anterior mandibular.

SUMMARY: The objective of the study was to determine the morphology of the mandibular incisive canal (MIC) and its location using cone beam computed tomography (CBCT) in the population of Valdivia, Chile. Descriptive cross-sectional study. MIC was identified in the canine cross image in 83 quadrants. Age, gender, quadrants, length from buccal alveolar ridge of canine to MIC, lingual and buccal cortical of canine to MIC, mandibular base of canine to MIC, and location of MIC (lingual, middle and buccal third) were recorded. Measurements were recorded in millimeters. Independent sample Student-T test was performed to determine length variables and Chi-square test was performed to determine spatial location of MIC, in relation to age group and gender. MIC was evaluated in all samples (100 %). MIC was found mainly in the mandibular third quadrant (p < 0.05). The mean from the MIC to the lingual cortex is 5.25 mm ? 1.42 mm (right) and 5.24 mm ? 1.18 mm (left). The mean from the MIC to the buccal cortex was 4.42 ? 1.29 mm (right) and 4.53 mm ? 1.24 mm (left). The mean between the center of the canal and the buccal alveolar ridge was 18.89 mm ? 2.68mm (right) and 18.20 mm ? 3.06 mm (left), the mean from the center of the MIC to the basal edge was 9.77 mm ? 1.93 (right) and 10.12 mm ? 1.92 mm (left). A greater distribution of MIC was found in the mandibular third quadrant. MIC was identified in 100 % of the samples through CBCT, therefore, its use as a complementary examination should be considered when planning surgeries in the anterior mandibular area.

Evaluation of Anatomical Characteristics of Mandibular Incisive Canal in a Turkish Subpopulation Using Cone Beam Computed Tomography

ABSTRACT Objective: To assess the anatomical characteristics of mandibular incisive canal and to describe the occurrence of anatomical variations according to side, age and gender using cone beam computed tomography (CBCT). Methods: A retrospective study using CBCT images was performed to evaluate mandibular incisive canal in mandible of 100 patients. Both right and left sides were studied (n = 200). Axial, sagittal, cross-sectional and panoramic images were evaluated, and three dimensional images were also reconstructed and evaluated, as necessary. The morphology, course and length of mandibular incisive canals and the inner and outer diameters of the canals were measured. Results: The incisive canal was found in 87% of the scans. The mean endpoint was approximately 10.98 and 10.26 mm anterior to the mental foramen for left and right side, respectively, without a significant difference (p > 0.05). The mean distance from the lower border of the mandible was 10.7 mm and its course was closer to the buccal border at the starting point while it deviates lingually through the anterior of the mandible. Significant difference was found between gender, side and age groups (p < 0.05). Conclusion: Awareness of these anatomical variations is important to avoid neurovascular damage during surgical intervention and anaesthetic applications. Cone beam computed tomography is an effective imaging modality in the detection of lingual foramina and canals. Further studies with larger data samples are necessary in comparison and estimation of anatomical results.

Morphological features of the incisive canal in patients of the first adult age

The incisive canal and its contents are often subject to intervention in maxillofacial surgery, otorhinolaryngology, and various areas of dentistry. The purpose of this paper is to study the variability of the dimensional and topographic characteristics of the incisive and nasal foramina of the incisive canal depending on the gender, shape, and parameters of the craniofacial complex in the first adult age. The authors have studied the parameters of the craniofacial complex, such as the morphological facial height, the upper morphological facial height, and the morphological facial breadth. They also have determined the Garson facial index and the upper face index. Cone-beam computerized tomography has been used in order to determine the number of foramina of Stensen and incisive foramina, their mesiodistal and vestibulo-lingual diameters, the shape of the incisive foramen; the distance from the incisive foramen to the labial inferior and palatal inferior points of the alveolar process; the distance from the incisive foramen to the central incisors, lateral incisors, canines of the maxilla; the bone density around the incisive canal; the length, shape, and type of incisive canal. Quantitative data were processed by variational statistical methods using the Statistica software package for Windows v 10.0. The significance of differences between groups was assessed using the Kolmogorov- Smirnov criterion at a significance level of p<0.05. It has been discovered that the incisive canal, the nasal and incisive foramina had a pronounced individual variability in size, shape, and topography depending on the gender, shape, the Garson facial index and upper face index, as well as the presence of correlations between the diameters and the number of nasal and incisive foramina. The authors have determined the values of bone tissue density in the area of the nasal and incisive foramina.

Topographical variations of the incisive canal and nasopalatine duct in human fetuses / 대한해부학회지

Prevalence and morphometric characteristics of the mandibular incisive canal through panoramic radiographs in a Chilean population / Prevalencia y características morfométricas del canal incisivo mandibular a través de radiografías panorámicas en población chilena

The mandibular incisive canal (MIC) is a continuation of the mandibular canal, anterior to the mental foramen, containing the neurovascular bundle of the teeth in anterior mandibular segment. The aim of this study was to calculate the prevalence and analyze the morphometric parameters of MIC in a Chilean population through digital panoramic radiographs. A cross-sectional study was performed using 500 digital panoramic radiographies of adult individuals. The prevalence of MIC was set in different sexes, age groups and proximity to teeth; in addition to the morphometric parameters of length, width (diameter) and distances of MIC to dental element and the mandibular base. General MIC prevalence was 53 % (265 cases), 49.9 % in women and 57 % in men. In the age groups, prevalence was higher in men, MIC was predominantly associated to first premolars (98.2 % - women; 90 % - men), however a relevant number (42.6 % women; 55.1 % - men) was close to the canines. The MIC length ranged from 2.6 to 18 mm (median - 5 to 8 mm), the width of 0.8 to 5.4 mm (median - 2 to 3 mm), the distance to other elements from 0.6 to 12 , 5 mm (medians - 5 to 7 mm) and the margin of the mandible from 4.1 to 16.7 mm (median - 8 to 10 mm). The length decreases in older age groups regardless of sex. Width and distance the mandibular base was larger in men compared to women.

El canal incisivo mandibular (MIC) es una continuación del canal mandibular, anterior al agujero mentoniano, que contiene la rama neurovascular de los dientes en el segmento mandibular anterior. El objetivo de este estudio fue calcular la prevalencia y analizar los parámetros morfométricos del MIC en una población chilena mediante radiografías panorámicas digitales. Se realizó un estudio de corte transversal utilizando 500 radiografías panorámicas digitales de individuos adultos. La prevalencia de MIC se estableció en diferentes géneros, grupos de edades y proximidad a los dientes; Además de los parámetros morfométricos de longitud, ancho (diámetro) y distancias de MIC al diente y a la base mandibular. La prevalencia general de MIC fue de 53 % (265 casos), 49,9 % en mujeres y 57 % en hombres. En los grupos de edad, la prevalencia fue mayor en los hombres, el MIC se asoció predominantemente a los primeros premolares (98,2 % - mujeres, 90 % - hombres), sin embargo un número relevante (42,6 % mujeres y 55,1 % hombres) estaba cerca de los caninos. La longitud del MIC osciló entre 2,6 y 18 mm (medianas de 5 a 8 mm), el ancho de 0,8 a 5,4 mm (medianas de 2 a 3 mm), la distancia a otros elementos de 0,6 a 12,5 mm (medianas de 5 a 7 mm) y al borde de la mandíbula de 4,1 a 16,7 mm (medianas de 8 a 10 mm). El largo disminuye en los grupos de mayor edad independientemente del sexo. Ancho y distancia a la base mandibular fue mayor en hombres que en mujeres.

Three dimensionally reconstructed of the mandibular incisive canal by CBCT / 口腔疾病防治

Objective@#To find out the existence of Mandibular Incisive Canal (MIC) through CBCT scanning and measure its 3D relationship with the surrounding tissue, so as to provide protection for the operation in submental area. @*Methods@# CBCT images of 100 patients were measured and three dimensionally reconstructed. The measurement include following items, the existence of the MIC; vertical and horizontal diameter of MIC; vertical distance from MIC to the mandibular buccal and lingual wall; to the root apex, to the inferior border of mandible and alveolar crest in corresponding points (the mandibular first premolar, canine and incisor). @*Results @# the MIC was 100% visible in CBCT. The mean distance between MIC and buccal bone plate and lingual bone plate was 3.52 ± 0.54 mm and 5.37 ± 0.25 mm. The average distance from the inferior border of the mandible, the apex of the root and the crest of the alveolar bone was 10.44 ± 0.61 mm、10.57 ± 0.76 mm and 20.21 ± 0.83 mm relatively. The distance from MIC to the inferior border of the mandible in male was 10.70 ± 0.43 mm and 10.17 ± 0.63 mm in female, P<0.05. @*Conclusion @# The detection rate of MIC is high and there are many variations. It was suggested that the location and size of the MIC should be checked in CBCT in each patient before operation, which is helpful to avoid surgical complications in submental area.

Measurement of mandibular incisive canal by cone beam CT / 中华放射学杂志

Objective This study was conducted to measure the mandibular incisive canal (MIC) by cone beam computed tomography(CBCT)and to assess 3?dimensional structure, course and adjacent structure of the MIC , in order to ensure safe region for surgery of the mandibular interforaminal area. Methods A total of the CBCT images from 83 patients were studied and measured. The detection rates of MIC were calculated The diameter of the MIC and the distances from MIC to the labial and lingual cortices and the inferior border of the mandible and tooth tips were measured at canines and lateral incisors. Results MIC was found in 67.8%of the patients. In the position of canine, the diameter of MIC, the mean distance of the MIC to the tips of the teeth, to the buccal border of the mandible , to the lingual border of the mandible and the inferior border of the mandible were (1.3±0.4), (8.9±2.9), (4.3±0.9), (5.2±1.1) and (8.6± 1.5) mm, respectively. In the position of the incisor, the distance of MIC, the mean distance of the MIC to the tips of the teeth, to the buccal border of the mandible , to the lingual border of the mandible and the inferior border of the mandible were (1.0 ± 0.3), (13.3 ± 4.0), (4.2 ± 0.9), (5.9 ± 0.9) and (8.9 ± 1.8) mm, respectively. Conclusion CBCT clearly show three dimensional structure, course and adjacent structure of the MIC. Preoperative CBCT can provide vital information for surgery of the mandibular interforaminal area.

Sexual dimorphism in the incisive canal in humans: a literature review / Dimorfismo sexual del canal incisivo en cráneos humanos: revisión de la literatura

Aim: To describe the morphometric characteristics of the maxillary incisor canal (IC) in human beings by gender. Material and method. Descriptive study. A systematic search for articles related to anatomical and topographical variations of the IC by sex and published in the last ten years was performed in the Medline database. Selected publications presented the following criteria: Number of samples and average values, in millimeters (mm), for length, diameter and distance from the IC to the maxillary central incisors (ICM). In addition, author and year of publication were considered. Data were presented using descriptive statistics. Results. Three studies were selected. In men, IC average dimensions were higher in diameter (2,79+/-0,94 mm v/s 2,43+/-0,85 mm), length (11,96+/-2,73 mm v/s 10,39+/-2,47 mm) and distance from the apex and middle third of the root of the MCI than in women. Conclusion. IC morphometric values were higher in men. It is important to keep in mind IC dimensions vary according to gender when planning surgeries and rehabilitations in this area of the oral cavity.

Objetivo. Describir las características morfométricas del canal incisivo del maxilar (CI) según el género en humanos. Material y método. Estudio descriptivo. Se realizó una búsqueda sistemática en la base de datos de MEDLINE, sobre artículos relacionados con las variaciones anatómicas y topográficas del CI entre géneros. Se registró autor, año de publicación, cantidad de muestras y valores promedios en milímetros de la longitud, diámetro y distancia del CI con respecto a los incisivos centrales del maxilar (ICM). Resultados. Se analizaron 3 Artículos. Las dimensiones promedio del CI fueron mayores en los hombres que en las mujeres tanto en el diámetro (2.79+/-0.94 mm v/s 2.43+/-0.85 mm ), longitud (11.96+/-2.73 mm v/s 10.39+/-2.47 mm) y distancia con el ápice y punto medio de la raíz de los ICM. Conclusión. Las características morfométricas del CI fueron mayores en hombres. Se debe tener en cuenta que las dimensiones del CI varían dependiendo del sexo para la planificación de cirugías y rehabilitación en este sector de la cavidad oral.

Presencia Bilateral del Canal Incisivo de la Mandíbula: Una Estructura Anatómica con Relevancia Clínica / Bilateral Presence of Mandibular Incisive Canal: An Anatomical Structure with Clinical Relevance

La región anterior de la mandíbula generalmente se considera un área quirúrgica segura, con pocos riesgos de daño a estructuras anatómicas importantes. Sin embargo, esta región contiene un canal intraóseo, el canal incisivo de la mandíbula (CIM), que es la continuación del canal mandibular mesial al foramen mental, donde se encuentra el nervio incisivo de la mandíbula acompañado de estructuras vasculares. Su presencia y el curso de la inervación mandibular anterior siguen siendo un tema de debate y algunos autores incluso niegan su existencia. Este reporte define el curso anatómico del CIM bilateralmente mediante tomografía computarizada, confirmando la presencia del nervio incisivo de la mandíbula mediante técnica microquirúrgica asistida por endoscopía. El conocimiento de la presencia, longitud y diámetro del CIM pueden jugar un rol importante en el éxito de la oseointegración de un implante y prevenir alteraciones sensoriales postoperatorias.

The anterior mandible region is generally considered a safe surgical area, involving few risks of damage to vital anatomic structures. However, this area has an intraosseous canal, the mandibular incisive canal (MIC), the continuation of the mandibular canal, mesial to the mental foramen where the mandibular incisive nerve along with vascular structures is located. The presence and course of the incisive nerve remains a matter of debate and some authors even neglect it. This case report defines the anatomic courses of the incisive mandibular canal bilaterally using cone-beam computed tomography and confirms the presence of the incisive nerve by endoscopically assisted surgical technique. The knowledge of the MIC presence, length and diameter may play an important role in successful implant osseointegration and prevention of postoperative sensory disturbances.

Multi-slice spiral CT appearances of maxillary incisive canal:Observation of normal anatomy and abnormalities / 中国医学影像技术

Objective To observe the morphological features of the incisive canal in normal anatomy and abnormalities with multi-slice spiral CT (MSCT). Methods MSCT findings of 108 normal subjects and 65 patients with abnormalities involving incisive canal were retrospectively analyzed. Results The normal incisive canal were classified into 3 types according to the morphology of the nasal opening:two openings, short bony crest and one opening (37.04%, 33.33% and 29.63%, respectively), as well as cylinder, Y-shaped and pyramidal (59.26%, 37.04% and 3.70%) in coronal images, and cylinder, pyramidal and fusiform (84.26%, 14.81% and 0.93%) in sagittal images. The maximum diameter of the nasal and palatal opening was (4.67±1.31) mm and (3.51±0.88) mm (P<0.05). The length of the incisive canal was (10.71±1.95) mm, (11.51±1.97) mm in male and (9.91±1.58) mm in female respectively, and gender difference was found (P<0.05). The angle between the posterior wall and the hard palate was (118.51±9.44)°. The upper and lower length from the anterior wall of the incisive canal to the cortical palate was (9.29±1.26) mm and (7.12±1.21) mm, respectively (P<0.05). The manifestations of abnormalities involving incisive canal including enlargement (47.69%), narrowing (46.15%), shortening (3.08%) and interruption (3.08%) were observed. Conclusion The morphology of the incisive canal can be clearly delineated with MSCT and post processing techniques. It is extremely valuable for avoiding potential complications during surgical procedures such as implant placement and helpful to the diagnosis and treatment of abnormalities involving maxillary incisive canal.

Anatomic study of the incisive canal in relation to midpalatal placement of mini-implant / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to reveal the position of the incisive foramen in relation to the incisive papilla and cusp tips. METHODS: Plaster models and CT images of 25 adult orthodontic patients were used to measure the width of the incisive canal and positions of the anterior and posterior borders of the incisive foramen in relation to the incisive papilla. RESULTS: The palatal surface distance from the interdental papilla between the maxillary central incisors to the posterior border of the incisive foramen along the palatal surface was 1.7 fold of the distance from the interdental papilla between the central incisors to the posterior border of the incisive papilla. The distance between the posterior border of the incisive papilla and posterior border of the incisive foramen along the palatal surface was 6.15 +/- 1.75 mm. The anteroposterior position of the posterior border of the incisive foramen was slightly anterior to the lingual cusp tips of the maxillary 1st premolars. The width of the incisive foramen was 4.03 +/- 0.64 mm, therefore it is recommended to position the mini-implant more than 3 mm laterally when placing a mini-implant lateral to the incisive foramen, from the center. CONCLUSIONS: These results can be used as a reference in presuming the position of the incisive foramen when placing mini-implant in the anterior palate area.

The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images / 대한구강악안면방사선학회지

PURPOSE: To assess the width of the labial alveolar bone of the incisive canal and the width of the incisive canal on spiral computed tomographic images of the anterior portion of the maxilla. MATERIALS AND METHODS: Study materials included 38 CT scans taken for preoperative planning of implant placement. Axial cross-sectioned image entirely showing the incisive canal was selected and scanned with 600 DPI resolution. The width of the labial alveolar bone of the incisive canal at an orifice to the oral cavity, middle portion, and an orifice to the nasal cavity and the diameter of the incisive canal at the middle portion were determined by two specialist using Digora for Windows 2.1. The statistical analyses were carried out using SPSS 12.0.1. RESULTS: When the maxillary central incisors remained, the mean labial alveolar bone width were 6.81+/-1.41 mm, 6.46+/-1.33 mm, and 7.91+/-1.33 mm. When the maxillary central incisors were missed the mean width were 5.42+/- 2.20 mm, 6.23+/-2.29 mm, and 7.89+/-2.13 mm. CONCLUSIONS: The labial alveolar bone width at middle portion and an orifice to the nasal cavity were of no statistical significant difference according to presence of the maxillary central incisors (P>0.05). The width between oral cavity and nasal cavity, middle portion and to nasal cavity revealed statistically significant difference (P<0.05).

A study of incisive canal using a cone beam computed tomography / 대한구강악안면방사선학회지

PURPOSE: To investigate the anatomical structure of the incisive canal radiographically by a cone beam computed tomography. MATERIALS AND METHODS: 38 persons (male 26, female 12) were chosen to take images of maxillary anterior region in dental CT mode using a cone beam computed tomography. The tube voltage were 65, 67, and 70 kVp, the tube current was 7 mA, and the exposure time was 13.3 seconds. The FH plane of each person was parallel to the floor. The images were analysed on the CRT display. RESULTS: The mean length of incisive canal was 15.87mm+/-2.92. The mean diameter at the side of palate and nasal fossa were 3.49 mm+/-0.76 and 3.89 mm+/-1.06, respectively. In the cross-sectional shape of incisive canal, 50% were round, 34.2% were ovoid, and 15.8% were lobulated. 87% of incisive canal at the side of nasal fossa have one canal, 10.4% have two canals, and 2.6% have three canals, but these canals were merged into one canal in the middle portion of palate. The mean angles of the long axis of incisive canal and central incisor to the FH plane were 110.3.+/-6.96 and 117.45.+/-7.41, respectively. The angles of the long axis of incisive canal and central incisor to the FH plane were least correlated (r = 0.258). CONCLUSION: This experiment suggests that a cone beam computed radiography will be helpful in surgery or implantation on the maxillary incisive area.

Supernumerary Tooth Germs in the Incistive Canal of Five Fetal Maxillas

Five fetal maxillas were obtained from the autopsy file of fetal postmortem examination, and were examined by serial micro-sections of frontal plane and horizontal plane. Especially the area around the incisive canal of the maxilla was carefully observed. The results are as follows. 1) In 5 fetal maxillas extra-dental laminas and supernumerary tooth germs which are severely malformed in shape are found in the dilated incisive canal, where prominent vessels and nerves are distributed. 2) The supernumerary tooth germs disclose almost normal histo-differentiation of odontoblast and ameloblast, and there shows relatively abundant perifollicular fibrosis in the place of perifollicular bone. 3) It is observed that the over-growth of the extradental lamina from the dental ridge of deciduous central incisor frequently tends to direct toward the incisive canal that includes prominent vessels and nerves.