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INTERNAL ROOT MORPHOLOGY OF PREMOLARS ACCORDING TO

RADIOGRAPHIC IMAGING

MORFOLOGÍA DE LA RAÍZ INTERNA DE LOS PREMOLARES SEGÚN IMÁGENES

RADIOGRÁFICAS

Autores: ¹Leonela Karelys Zambrano Balcázar, ²Roberto Johnny Romero Chévez,

Dick Bryan

Vera Morán,

Bernarda Andrea Sánchez Arteaga,

Kevin Roberto Romero Díaz.

ORCID ID: https://orcid.org/0009-0001-7978-317X

ORCID ID: https://orcid.org/0009-0009-1985-5985

ORCID ID: https://orcid.org/0000-0003-2460-2527

ORCID ID: https://orcid.org/0000-0002-1347-1798

ORCID ID: https://orcid.org/0009-0009-3854-1703

E-mail de contacto: leonela.zambranob@ug.edu.ec

E-mail de contacto: roberto.romeroch@ug.edu.ec

E-mail de contacto: dick.veram@ug.edu.ec

E-mail de contacto: bernarda.sancheza@ug.edu.ec

E-mail de contacto: kevin.romerod@ug.edu.ec

Afiliación:

1*2*3*4*5*

Universidad de Guayaquil, (Ecuador).

Artículo recibido: 2 de Agosto del 2025

Artículo revisado: 4 de Agosto del 2025

Artículo aprobado: 8 de Agosto del 2025

Odontóloga graduada de la Universidad de Guayaquil, (Ecuador).

Doctor en Odontología graduado de la Universidad de Guayaquil, (Ecuador). Especialista en Endodoncia graduado de la Universidad de

Guayaquil, (Ecuador). Diplomado en Docencia Superior graduado de la Universidad de Guayaquil, (Ecuador). Magíster en Investigación

Clínica y Epidemiológica graduado de la Universidad de Guayaquil, (Ecuador).

Odontólogo graduado de la Universidad de Guayaquil, (Ecuador). Cirujano Dentista Especialista en Rehabilitación Oral con mención en

Prótesis graduado de la Universidad de Concepción, (Chile).

Odontóloga graduada de la Universidad de Guayaquil, (Ecuador). Especialista en Endodoncia graduada en la Universidad San Francisco

de Quito, (Ecuador).

Odontólogo graduado de la Universidad de Guayaquil, (Ecuador). Especialista en Radiología Bucal y Maxilofacial graduado en la

Universidad Peruana Cayetano Heredia, (Ecuador).

Resumen

El presente estudio aborda el tema de la

morfología interna de los conductos radiculares

y el uso de radiografías para su diagnóstico. El

objetivo se centra en establecer la morfología

de los conductos radiculares en premolares a

través de imágenes radiográficas. La

metodología implicó una investigación

descriptiva, observacional y transversal con un

enfoque cualitativo, utilizando una muestra de

40 piezas dentales extraídas (tanto premolares

superiores como inferiores). Las técnicas e

instrumentos utilizados incluyeron formularios

de observación basados en el análisis de

radiografías, fotografías y un procesador de

placas de fósforo. Se tomaron radiografías

periapicales para observar el sistema de

conductos radiculares y se utilizó un

procesador de placas de fósforo para obtener

imágenes más nítidas. Se identificaron

conductos accesorios o colaterales dentro de la

morfología Tipo I, representando el 7,5% del

total, así como deltas apicales, también con una

incidencia del 7,5%. Cabe destacar que el 85%

de los especímenes no mostraron variaciones

morfológicas. El estudio concluyó que la

anatomía de los sistemas de conductos

radiculares de los premolares es variable, lo

que enfatiza la importancia de comprender

estas variaciones para el éxito del tratamiento

endodóntico. Se observó que el 45 % de los

premolares estudiados presentaban una raíz,

mientras que el 55 % presentaban dos raíces.

La mayoría de los premolares presentaban uno

o dos conductos radiculares, con diferentes

configuraciones según la clasificación de

Vertucci.

Palabras clave: Morfología radicular

interna, Premolares, Radiografía,

Clasificación de Vertucci.

Abstract

The present study addresses the topic of the

internal morphology of root canals and the use

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of radiographs for their diagnosis. The

objective focuses on establishing the

morphology of root canals in premolars

through radiographic imaging. The

methodology involved a descriptive,

observational, and cross-sectional research

with a qualitative approach, using a sample of

40 extracted dental pieces (both upper and

lower premolars). Techniques and instruments

utilized included observation forms based on

the analysis of radiographs, photographs, and a

phosphor plate processor. Periapical

radiographs were taken to observe the root

canal system, and a phosphor plate processor

was used to obtain sharper images. Accessory

or collateral canals were identified within Type

I morphology, representing 7.5% of the total,

as well as apical deltas, also with an incidence

of 7.5%. It is noteworthy that 85% of the

specimens showed no morphological

variations. The study concluded that the

anatomy of premolar root canal systems is

variable, emphasizing the importance of

understanding these variations for the success

of endodontic treatment. It was observed that

45% of the studied premolars had one root,

while 55% had two roots. Most premolars had

one or two root canals, with different

configurations according to Vertucci's

classification.

Keywords: Internal root morphology,

Premolars, Radiography, Vertucci

classification.

Sumário

O presente estudo aborda o tema da morfologia

interna dos canais radiculares e o uso de

radiografias para seu diagnóstico. O objetivo é

estabelecer a morfologia dos canais radiculares

em pré-molares por meio de imagens

radiográficas. A metodologia envolveu uma

pesquisa descritiva, observacional e transversal

com abordagem qualitativa, utilizando uma

amostra de 40 peças dentárias extraídas (pré-

molares superiores e inferiores). As técnicas e

instrumentos utilizados incluíram formulários

de observação baseados na análise de

radiografias, fotografias e um processador de

placa de fósforo. Radiografias periapicais

foram realizadas para observar o sistema de

canais radiculares, e um processador de placa

de fósforo foi utilizado para obter imagens mais

nítidas. Canais acessórios ou colaterais foram

identificados dentro da morfologia Tipo I,

representando 7,5% do total, assim como deltas

apicais, também com incidência de 7,5%. Vale

ressaltar que 85% dos espécimes não

apresentaram variações morfológicas. O estudo

concluiu que a anatomia dos sistemas de canais

radiculares de pré-molares é variável,

enfatizando a importância da compreensão

dessas variações para o sucesso do tratamento

endodôntico. Observou-se que 45% dos pré-

molares estudados apresentavam uma raiz,

enquanto 55% apresentavam duas raízes. A

maioria dos pré-molares apresentava um ou

dois canais radiculares, com diferentes

configurações de acordo com a classificação de

Vertucci.

Palavras-chave: Morfologia radicular

interna, Pré-molares, Radiografia,

Classificação de Vertucci.

Introducción

This study addresses the topic of the internal

morphology of root canals and the use of

radiographs for diagnosis. Internal root canal

morphology refers to the shape and internal

structure of the root canals located within the

tooth roots. Premolars are a type of tooth with a

single root and generally two or three root

canals. Radiographic imaging is a technique

used in dentistry to obtain images of teeth and

surrounding structures, which can include

methods such as computed tomography, digital

radiography, phosphor plate processing, and

clearing techniques. The root canal system in

premolars presents a complex morphology,

which can pose a challenge for dental

professionals when attempting to differentiate

and properly treat these canals. Vertucci

classified root canals into eight types, leading to

various other classifications proposed by

different authors to describe the variations in

root canal morphology. Studies conducted in

countries such as Chile, Peru, Mexico, and

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Argentina have investigated the number of roots

and the configuration of root canals in

premolars within their populations, using

radiographic methods like computed

tomography, digital radiography, phosphor

plate processing, and clearing techniques. These

investigations have highlighted the complexity

and variability of root canal morphology in

premolars, noting the influence of ethnic factors

on these differences.

Various studies have described anthropological

variations in the anatomy of the root canal

system, which has led to discrepancies in the

literature regarding the morphology of

permanent teeth canals. These differences

contribute to potential errors by professionals,

who may face difficulties in identifying the

characteristics of the canals. Such

morphological variations may be due to

significant ethnic differences and the inherent

challenges in studying the complex root canal

system (Greco et al., 2009). The distinction

between internal and external root canal

morphology has been a challenge in dentistry

until Vertucci classified the system into eight

types. Subsequently, various other

classifications have been proposed due to the

high variability of the canals (Retamoso, 2021).

The literature indicates that upper premolars

show highly variable root canal morphology

(Soares & Goldberg, 2002, cited in Oporto et

al., 2010). Conversely, studies in Chile have

revealed that the anatomy of maxillary

premolars is relatively straightforward

compared to other ethnic groups (Monardes et

al., 2021).

A study conducted in Argentina on lower

premolars states that even when they have a

single root canal, these teeth can exhibit

complex anatomy. It is highlighted that a single

canal can show various cross-sectional

morphologies, ranging from circular to pinched

shapes (Berchialla et al., 2022). Recently, in a

South African subpopulation, 13 different

configurations for maxillary premolars were

identified, while in an Egyptian subpopulation,

11 different canal configurations were observed

(Buchanan et al., 2020). The complex anatomy

of mandibular premolar root canals may not be

detectable in routine radiographs. Periapical

radiographs represent three-dimensional

anatomy in a two-dimensional image, which

can result in missing important features of the

tooth and surrounding tissues, especially in the

mesiodistal plane. Therefore, features present in

the vestibulolingual dimension may go

unnoticed (Bolaños & Macías, 2018). In a

theoretical context, the internal root

morphology of premolars is characterized by its

anatomical variability, including fused roots,

accessory roots, single or multiple root canals,

among other features. Radiographic imaging

has been an essential tool in the diagnosis and

planning of endodontic treatments; however, its

accuracy may be influenced by factors such as

the radiographic technique used, the position of

the tooth within the oral cavity, and the quality

of the radiographic equipment. Therefore,

understanding these factors that affect the

visualization of the internal root morphology of

premolars has been crucial for accurate

diagnosis and successful endodontic treatment.

Finally, the use of techniques and

methodological tools in research on the internal

root morphology of premolars, based on

radiographic imaging, has provided substantial

benefits to students, professionals, and patients

in dentistry. From an educational perspective, it

has enabled advanced learning, the

development of research skills, and practical

application of knowledge. For professionals, it

has improved clinical practice, ongoing

professional development, and the quality of

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patient care. Regarding patients, it has resulted

in more accurate diagnoses, reduced

complications, and improved outcomes of

endodontic treatments, thereby benefiting oral

health and patients' quality of life.

Consequently, the purpose of this research was

to determine the morphology of the root canals

in premolars using radiographic imaging.

Additionally, the study analyzed classifications

of the root canal system, quantified the number

of roots and root canals found in premolars,

classified the types of root canals according to

Vertucci's classification, and finally identified

the presence of morphological variations in the

premolars analyzed radiographically. The

research question addressed was: What is the

internal root morphology of premolars as

analyzed radiographically?

The study conducted by Barrón & Sánchez

(2019) analyzed variations in the morphology

of canal systems in the first and second

mandibular premolars of patients who visited

the imaging department of the Universidad

Autónoma de Nayarit. It was observed that the

most common canal system was Type I in both

types of premolars, although other anatomical

variations were also identified. It was concluded

that most mandibular premolars had a single

canal, with a higher frequency of anatomical

variables Type III and V. These variations in the

internal anatomy of mandibular premolars are

important for clinical professionals. From a

practical perspective, the internal root

morphology of premolars has been extensively

studied in dentistry due to its relevance in

endodontic procedures. The variability in root

anatomy can significantly influence treatment

success, making it essential for dentists to

thoroughly understand it. Consequently,

investigating how radiographic imaging affects

the visualization and understanding of premolar

root morphology provides valuable information

to improve clinical practice and reduce potential

complications during endodontic treatments.

In the study by Carosi et al. (2022), the root

canal morphology of maxillary first premolars

was examined using cone-beam computed

tomography (CBCT) in a sample of 50

Argentine patients. It was found that the most

common internal morphology type for

maxillary first premolars was Type IV

according to Vertucci’s classification.

Significant agreement was observed between

the right and left sides regarding the types of

morphology, as well as in the number of roots.

These findings are relevant for appropriate

endodontic treatment. Ontaneda (2019),

evaluating the canal system in macerated roots

from 50 teeth, found that 60% of the teeth had a

single canal, 36% exhibited two canals, and 2%

showed two fused roots in the apical third with

a specific canal configuration. Maceration

proved to be an effective procedure for

identifying the anatomy of the root canal system

and its variations (Ontaneda, 2019). The study

by Castillo et al. (2023) focused on the root

canal system of second maxillary and

mandibular premolars using the technique of

dental maceration, in a sample of 100 second

premolars from an Ecuadorian population. It

was found that Vertucci’s Type I classification

was the most predominant in both upper and

lower premolars, followed by less common

classifications. Maceration allowed for three-

dimensional observation of the internal tooth

anatomy, greatly aiding in understanding its

morphology.

Moreno et al. (2021) mention that mandibular

premolars can present complex anatomy, with

variations ranging from Type I to Type V

according to Vertucci’s classification.

Furthermore, these teeth may have C-shaped

canals, which pose an additional challenge for

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proper endodontic treatment. Root canal

anatomy can vary depending on factors such as

ethnicity, gender, and age. The pulp chamber is

the space inside the tooth that contains the

dental pulp and is mainly coated with dentin,

except near the apex. It divides into two parts:

the pulp chamber and the root canal. The pulp

chamber is the crown portion of the pulp cavity,

located centrally within the crown and

conforms to its exterior shape. It is generally of

considerable size and houses the coronal pulp

(Soares et al., 2002). In terms of shape, the pulp

chamber can be described as cubic, with six

surfaces called mesial, distal, vestibular,

palatolingual, roof, and floor. These surfaces

are not flat but tend to be convex or concave,

following the structure of the corresponding

outer walls. The volume of the pulp chamber

constantly changes due to variations in wall

shape, influenced by ongoing physiological

changes in the dentin (Brau, 2014). The pulp

chamber is composed of the roof, the floor (or

cervical wall), and the surrounding lateral walls.

The roof is the occlusal or incisal part of the

pulp cavity, shaped concavely toward the

occlusal surface or incisal edge, with diverticula

that extend toward the tips of the cusps where

the pulp horns are located. The floor or cervical

wall is the opposite surface to the roof, convex

in shape, and contains the openings of the root

canals. The lateral walls are named according to

their orientation: vestibular, lingual or palatal,

mesial, or distal (Soares et al., 2002).

A root canal is defined as the connection

between the pulp chamber and the

periodontium, extending along the mid-zone of

the root. Regarding dental root morphology,

three main forms can be identified. Simple roots

correspond to single-rooted or multi-rooted

teeth with clearly differentiated roots (Brau,

2014). Bifurcated roots, also known as divided

roots, originate from well-differentiated roots

and can be wholly or partially split. Fused roots

result from the union of two or more roots that

merge into a single dental structure (Brau,

2014). Concerning the size of root canals, two

main aspects must be considered. First, the

longitudinal caliber varies along the length of

the canal, being widest at the pulp floor and

narrowing progressively toward the apex. This

diameter can show variations such as

convergent walls toward the apex, parallel

walls, or divergent walls (Brau, 2014). In young

teeth whose roots have not yet fully developed,

the root canal may be extremely wide, with an

apical diameter larger than the cervical diameter

due to incomplete root formation. Regarding the

shape of the canal in cross-section, it can be

circular, elliptical, or C-shaped, depending on

the root morphology and the configuration of

the root canal (Brau, 2014). The root canal

generally follows the central axis of the root and

can be straight, curved, or kinked. Curved

canals may present varying degrees of

curvature, such as partial bends, full curvatures,

kinks, or dilacerations, which can influence

endodontic procedures (Brau, 2014). According

to a study cited by Brau (2014), approximately

84% of root canals exhibit curvatures.

Regarding the first maxillary premolar, it is

notable that this tooth typically has two roots,

one vestibular and one palatal, according to

multiple authors, which is a characteristic

feature of its anatomy (Checya & Andrade,

2022). Concerning the pulp chamber, it is

described as being wider in the vestibulolingual

direction than in the mesiodistal direction, with

vestibular and palatal pulp horns present, the

vestibular horn generally being larger.

Additionally, most cases show that this

premolar has two roots, with single-root cases

being significantly less common (Soares et al.,

2002). As for the root canal in the first maxillary

premolar, it may have one, two, or even three

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canals. In most cases, two canals are observed,

which tend to be narrow and straight, even when

the tooth has only one root. The presence of

three canals—two vestibular and one palatal—

is less common and may pose challenges during

endodontic treatment due to their narrowness

and difficult access (Soares et al., 2002).

Conversely, the second maxillary premolar

typically presents with a single root in about

95% of cases. Its root is usually longer than that

of the first premolar and flattened mesiodistally

with a distal inclination, as noted by Checya &

Andrade (2022). The pulp chamber is similar to

that of the first premolar but larger, with two

projections housing the pulp horns, which are

usually nearly equal in size (Moenne, 2013).

The root canal of the second maxillary premolar

often contains a single canal, which tends to be

oval in shape in a cross-section—compressed

mesiodistally and broader vestibulopalatally.

Sometimes, two canals are present, with various

configurations that may converge into a single

apical foramen or remain separate with

independent foramina (Soares et al., 2002).

The mandibular first premolar is characterized

by an oval-shaped root in cross-section, with a

small lingual conicity, according to Moenne

(2013). Its pulp chamber has two pulp horns: a

pointed large vestibular horn and a smaller

rounded lingual horn. The chamber is inclined

lingually and conical from cervical to apical,

with a uniformly conical outline up to its sharp

apex, positioned with a lingual tilt. The

anatomical variability of the root canals in

mandibular first premolars is broad, with one,

two, three, four, or even five canals reported,

including C-shaped canals, according to

Cardona & Fernández (2015) and other authors

(Burns & Herbranson, 2002; Játiva et al., 2022).

Particularly, the presence of multiple canals in

mandibular first premolars varies significantly,

with percentages ranging from 11.5% to 36%,

depending on Cohen & Burns and Vertucci.

These anatomical variations are attributed to

genetic, racial, and gender factors that influence

the root morphology of this tooth (Játiva et al.,

2022). The second mandibular premolar

typically has an oval-shaped root with an apical

conicity and a lingual and apical inclination, as

reported by Moenne (2013). Its pulp chamber is

broader vestibulolingually than mesiodistally

compared to the first premolar, with a roof

showing two concavities corresponding to the

cusps, more pronounced in the vestibular cusp,

especially in young individuals (Cardona &

Fernández, 2015).

Regarding the root canal of the second

mandibular premolar, it is commonly a single

canal, larger and less constricted mesiodistally

than the first premolar, with an oval shape in the

cervical and middle thirds, becoming circular in

the apical third, as mentioned by Quispe &

Valero (2021). The separation between the pulp

chamber and the root canal is also a

characteristic frequently observed (Vertucci &

Haddix, 2011). Histologically, it is common to

find ramifications within the root canal that

serve as communication pathways between the

dental pulp and the periodontal ligament. These

ramifications can occur anywhere along the root

and are known by different names based on

their location (Maynard et al., 2023, p. 48).

Vertucci proposed a classification of eight

configurations for the root canal system. Type I

is characterized by a single canal that extends

from the pulp chamber to the apex (Maynard et

al., 2023, p. 48). In Type II, two separate canals

originate from the chamber and fuse near the

apex to form one canal. Type III involves a

canal that splits in the middle third and then

joins again, ending as a single canal at the apex.

Type IV consists of two separate canals from

the chamber that remain distinct throughout

their course until the apex. Type V begins as a

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single canal in the chamber, divides into two,

and terminates as two separate canals at the

apex. Type VI features two canals that fuse in

the middle third, then split again, ending in two

separate foramina at the apex. Type VII

involves a canal that divides in the middle,

briefly fuses, and then divides again near the

apex, resulting in two individual canals. Lastly,

Type VIII is characterized by three separate

canals from the chamber to the root apex

(Maynard et al., 2023, p. 48).

Diaphanization is a process involving

decalcification, dehydration, fixation, and

staining of the root canals to facilitate their

examination. Various clarifying techniques

have been described in the literature, offering

the advantage of providing a three-dimensional

view of the root canal system (Arango et al.,

2023). Cone-beam computed tomography

(CBCT) is employed in dentistry as a

complementary diagnostic tool that enables

three-dimensional visualization of dental

structures, including root canal configurations

and their variations. Although it offers the

advantage of a lower radiation dose, its

limitation in slice thickness can make it difficult

to identify more complex root canal

arrangements. Additionally, CBCT may face

limitations regarding access, cost, and

calibration for the radiographic examination of

individual teeth—important considerations in

endodontic procedures (Rincón et al., 2022).

Currently, dental clinics are equipped with

digital radiography systems, such as digital

radiovisiography and phosphor plate imaging.

These tools are useful throughout all stages of

endodontic treatment, as each step requires

radiographic verification. While they provide

two-dimensional images that allow

visualization of the tooth, surrounding tissues,

and structures, digital radiographs also have

disadvantages, such as superimposition of

anatomical structures, which can hinder the

identification of root canal morphology, among

other issues (Rincón et al., 2022). The phosphor

plate processor is a wireless system that uses

reusable plates coated with phosphor material

for intraoral radiography. These thin, flexible,

and wireless plates can be reused multiple

times. The process involves exposing the plate

to X-ray radiation, capturing the image on the

phosphor coating, scanning the plate with a

high-speed reader, and producing an image that

is displayed on a monitor (Tomas et al., 2022;

Yesim & Seher, 2019).

Materials and Methods

This study was of a descriptive, observational,

cross-sectional, and qualitative nature. An

analytical-synthetic method was employed,

where radiographic examination was used to

observe the premolar samples to identify their

internal anatomy, including the number of

canals, the number of roots, and the

classification of the types of canals found. The

research was descriptive because it detailed the

root morphology observed in the

radiographically analyzed premolars, focusing

on the type of canal present and its variations.

The sample consisted of 40 extracted teeth (both

upper and lower premolars). Inclusion criteria

selected premolars with complete root

formation and no previous root canal treatment.

Teeth with root resorption, root caries, or

calcified canals were excluded. The techniques

and instruments used for data collection

included visual observation to differentiate and

classify the root canal system, as well as to

count the roots and canals of each sample. An

observation form based on radiograph analysis,

photographs, and a phosphor plate processor

was utilized. Periapical radiographs were taken

to evaluate the root canal system, and a

phosphor plate processor was used to obtain

clearer images. A review of bibliographic

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sources was conducted to establish the

theoretical framework, gathering information

on the morphology of the root canal system of

premolars. Extracted premolars, both upper and

lower, were collected according to the

established criteria. Radiographs of each

sample were taken from two orientations and

processed with the phosphor plate processor.

The samples were visualized using the software

of the phosphor plate processor, and the

configuration of the root canals was recorded on

the data collection sheet. The results were

organized into a table for subsequent analysis

and synthesis to determine the presence and

types of root canal configurations within the

Ecuadorian population.

Results and Discusión

Figure 1. Premolars Used as Study Sample

Tabla 1. Number of roots in the observed

premolars

Number of

Roots

Frequency

Percentage

One root

45.00%

Two roots

55.00%

Total

100.00%

Source: own elaboration

In the descriptive-observational study of 40

premolars, Table 1 presents the distribution of

the number of roots. The findings reveal that

45% (18 premolars) have a single root, while

55% (22 premolars) possess two roots.

Tabla 2. Number of root canals in premolars

observed radiographically

Number of

Root Canals

Frequency

Percentage

One canal

75.00%

Two canals

25.00%

Total

100.00%

Fuente: elaboración propia

In the descriptive-observational study of 40

premolars, Table 2 shows the distribution of the

number of root canals. The results indicate that

75% (30 premolars) have a single canal, while

only 25% (10 premolars) have two canals.

Table 3. Distribution of premolars according to

Vertucci's classification

Vertucci

Classification

Frequency

Percentage

Type I

55.00%

Type II

5.00%

Type III

12.50%

Type V

25.00%

Type VII

2.50%

Total

100.00%

Source: own elaboration

As shown in Table 3, of the 40 premolars

examined, 22 exhibited a single canal,

accounting for 55% of the sample. Additionally,

2 premolars had a Type II canal, which

represents 5%; 5 premolars displayed a Type III

canal, equivalent to 12.5%; 10 premolars

showed a Type V canal, corresponding to 25%;

and one premolar exhibited a Type VII canal,

making up 2.5%.

Table 4. Presence of collateral or secondary

canals and apical deltas in relation to

Vertucci's classification

Vertucci

Classification

Collateral or

Secondary

Canals

Apical Detas

Apical Deltas

Type I

7.5%

40%

Type II

Type III

12.5%

Type V

25%

Type VII

2.5%

Total

7.5%

85%

Fuente: elaboración propia

Ciencia y Educación

(L-ISSN: 2790-8402 E-ISSN: 2707-3378)

Vol. 6 No. 6.1

Edición Especial II 2025

Página 829

As shown in Table 4, of the 40 specimens

examined, collateral or accessory canals were

identified in Type I, representing 7.5% of the

total, as well as apical deltas, also with an

incidence of 7.5%. It is important to highlight

that 85% of the samples showed no

morphological variations. Moreno et al. (2021)

mention that the anatomy of premolars can be

complex, and this complexity may vary

depending on factors such as ethnicity, gender,

and age, following Vertucci's classification

ranging from type I to VIII. Various methods

are available to visualize the anatomy of root

canals, including diaphanization, computed

tomography, digital radiography, and digitized

images. In this particular study, periapical

radiographs were taken from two different

angles (buccolingual and mesiodistal) using a

phosphor plate processor. The results indicate

that, out of the 40 premolars studied, 75% had a

single canal and 25% had two canals, classified

according to Vertucci’s system. These findings

are consistent with previous research, such as

Ontaneda’s (2019) study, which also found a

similar distribution of canals in premolars.

Vertucci’s type I classification was the most

common in this study, accounting for 55% of

the samples. This finding aligns with

observations by Barrón & Sánchez (2019) and

Castillo et al. (2023) in similar populations.

However, it differs from Carosi et al.’s (2022)

findings in an Argentine population, where type

IV was the most prevalent. Overall, the results

of this study agree with existing literature

regarding the root canal morphology of

premolars, though some discrepancies can be

attributed to differences in studied populations

and imaging techniques used.

Conclusions

It was concluded that the anatomy of the root

canal system in premolars is variable, and

understanding these variations is crucial for the

success of endodontic treatment. It was

observed that 45% of the studied premolars had

one root, while 55% had two roots. Most

premolars had one or two root canals, with

different configurations according to Vertucci’s

classification. Additionally, variations in

internal root morphology were highlighted,

especially in Type I configurations. It is

suggested to conduct further research using

diverse variables and diagnostic methods, such

as computed tomography, to more accurately

visualize variations in the canal system. The

study also emphasizes the importance of

investigating the configurations and

morphological variations found to improve

diagnosis and prevent potential failures in

endodontic treatments. Several limitations were

identified in the research, such as the lack of

studies using conventional radiography and

phosphor plate processing equipment in

Ecuador, as well as the scarcity of scientific

literature on this topic within the country.

Despite these challenges, the utility and validity

of radiography with phosphor plates for

diagnosing certain variations in root canal

anatomy are highlighted, as demonstrated in

this study and supported by previous research.

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