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ORIGINAL ARTICLE
Year : 2021  |  Volume : 11  |  Issue : 1  |  Page : 73-79

Assessment of the distribution of facial root fenestration in maxillary anterior teeth in Saudi sub-population using cone-beam computed tomography: Retrospective study


1 Department of Periodontics, Riyadh Elm University, Riyadh, Saudi Arabia
2 Department of OMFS and Diagnostic Science, Division of Oral Radiology, Riyadh Elm University, Riyadh, Saudi Arabia
3 Department of Periodontology and Implantology, King Saud Medical City, Riyadh, Saudi Arabia
4 Department of Endodontic, Ministry of Health, Riyadh, Saudi Arabia

Date of Submission28-Nov-2019
Date of Decision16-Mar-2020
Date of Acceptance26-Mar-2020
Date of Web Publication09-Jan-2021

Correspondence Address:
Dr. Fawaz Hamad Alkazman
Department of Periodontics, Riyadh Elm University, P. O. Box: 84891, Riyadh 11681
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/sej.sej_180_19

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  Abstract 


Introduction: The aim of this study is to assess the destitution of facial root fenestration in maxillary anterior teeth among the Saudi population in cone-beam computed tomography (CBCT) scans.
Materials and Methods: A total of 100 CBCT scans of maxillary anterior teeth were evaluated for the presence, location, and type of the fenestration. The age, gender, number of fenestrations, and their location was displayed by frequency and percentage. Data were statistically analyzed.
Results: The overall prevalence of root fenestration in the facial bone of maxillary anterior teeth was 80%. It was higher in females (57.5%) than males. The most common tooth being affected by fenestration was lateral right incisor (35.0%). The most common type of root fenestration was Type IV (52.5%). No significant difference was found between all types of fenestrations and all age groups (P < 0.365). The highest mean of fenestration height was found in relation to the left canine (7.1 mm) and lowest was in lateral right incisor (4.9 mm).
Conclusions: Females and lateral right incisor areas were the most commonly affected by the root fenestration of Type IV.

Keywords: Cone-beam computed tomography, maxillary anterior teeth, periapical bone defect, prevalence, root fenestration


How to cite this article:
Alkazman FH, Abouelkheir HM, Almashat H, Alfahadi HR. Assessment of the distribution of facial root fenestration in maxillary anterior teeth in Saudi sub-population using cone-beam computed tomography: Retrospective study. Saudi Endod J 2021;11:73-9

How to cite this URL:
Alkazman FH, Abouelkheir HM, Almashat H, Alfahadi HR. Assessment of the distribution of facial root fenestration in maxillary anterior teeth in Saudi sub-population using cone-beam computed tomography: Retrospective study. Saudi Endod J [serial online] 2021 [cited 2021 Apr 15];11:73-9. Available from: https://www.saudiendodj.com/text.asp?2021/11/1/73/306604




  Introduction Top


Preoperative considerations, such as periapical lesions and alveolar bone defects, have a common effect on the endodontics treatment outcome.[1],[2],[3]

Mucogingival surgical procedures need the dental surgeon to have a precise knowledge of both normal and abnormal anatomic features of the alveolar process. The reflection of the alveolar bone during surgical procedures may inadvertently expose underlying alveolar defects, including dehiscences and fenestrations. Alveolar dehiscences and fenestrations are defects of the alveolar bone, which are most frequently observed by the dentist during soft- or hard-tissue surgery.[4],[5]

Fenestrations and dehiscences of the alveolar plate of bone are often detected during mucogingival surgical procedures. Deformities of the alveolar process discovered during these procedures can present surgical dilemmas which may seriously affect the outcome of treatment. While dehiscences and fenestrations are assumed to be nonpathological and deviate within the range of periodontal respectability, their misdiagnosed or unexpected nature may complicate periodontal surgical procedures or require changes in implant position procedures.[6] Previous studies have generally agreed to define a fenestration as a narrow defect of the alveolar radicular bone, which exposes the underlying root surface but does not include the alveolar margin.[7],[8]

Fenestration is a pathological structural variant of pulp-periodontal mucosal pathology and involves complex relationships of the teeth-periapical alveolar bone.[9],[10],[11] In addition, the alveolar bone is deviated with root apex exposure, excluding the alveolar bone margin.

Modern anatomy texts indicate a lack of fenestration details.[12] When the tooth root is denuded of bone, and the root surface is covered only by the periosteum and the gingiva, it is called fenestration. When the denuded areas only involving the alveolar margin are called dehiscences.[13]

The alveolar structure consists of an outer plate of cortical bone, and the inner socket wall consisted of the alveolar bone proper, which is seen as the lamina dura on X rays. Alveolar bone structure can differ in thickness, contour, and shape from person to person, and all of these differences can be normal and healthy.[8] These differences are caused by the peculiar relationship between the alveolar system morphology and the teeth. The bone contour normally conforms to the prominence of the roots with vertical depressions that taper in harmonious dental arches toward the margin.

The size of the teeth and the size of their bone housing are congruent. The contour of the marginal bone in a healthy periodontium follows the contour of the cementoenamel junction (CEJ) and is about 2 mm apical to it.[8]

The etiology of fenestration involved a variety of physiological and pathological factors, including root size and contours, tooth place, endodontic and periapical disease, trauma, bruxism, occlusal force, and tooth movement, and thin cortical bone.[14]

As a result of individual differences, obscure clinical manifestations of fenestration (persistent pain, discomfort, abscess, and other complex symptoms) also vary by patient. Some patients have no visible signs of pain, although the root fenestration of their teeth.[15] Due to its importance in endodontic and periodontal therapy, the present study aimed to assess the destitution of facial root fenestration in maxillary anterior teeth among the Saudi population using cone-beam computed tomography (CBCT).


  Materials and Methods Top


Sample acquisition

The current study was approved by the Scientific Research and Ethics Committee of Riyadh Elm University (registration number: FPGRP/43831003/307). A total of 100 CBCT scans randomly selected from the database of patients attending the clinics of Riyadh Elm University, College of Dentistry, were evaluated by two examiners for facial root fenestration of maxillary anterior teeth. The images were taken for different reasons, not related to the current study. The age range was from 12 to 79-years old (mean 33.1 ± 13.9). The age, gender, number of fenestrations, and their location was displayed by frequency and percentage. The CBCT machine used was GALILEOS Comfort Plus (Sirona Dental Systems, Inc.) with the following specifications: Tube potential 98 KV, Tube current 3–6 mA, Effective dose 28–154 μSV, Voxel size 0.25–0.125 mm, and the field of view 15 × 15 × 15.

Inclusion criteria

  • Permanent maxillary anterior teeth with complete development of roots
  • High-quality image showing the entire tooth and surrounding alveolar bone.


Exclusion criteria

  • No dental pathology (e.g., tumor)
  • No facial fracture or trauma
  • No malocclusion such as additional teeth or missing teeth
  • Orthodontically treated patients
  • Patients with a periodontal regeneration procedure


Assessment of images

Fenestration was identified as a tooth root protruding from a window-like opening or a defect in the alveolar bone without involving the alveolar margin as defined by Davies et al. and the American Association of Endodontic.[10],[16] Three points were highlighted:

  • A circumferential bony defect indicates that both the cortical bone and the tubular bone are penetrated concurrently and that the root is either directly in contact with the overlying epithelium or in combination with soft tissue fenestration
  • The uncovered root protrudes beyond the bone
  • The exclusion of the alveolar margin is noted to distinguish between fenestration and dehiscence.[6],[10]


Determine the location of fenestration

The root length was divided into three equal parts, from CEJ (point A) to root apex (point D). Then the investigator locates which a third of the root (coronal, middle, or apical third) contains the fenestration and determines the type of fenestration.

The coronal border of fenestration was assigned as point (B) and the apical border as point (C ([Figure 1].
Figure 1: Points to determine the location of root fenestration. A = CEJ point. B = coronal border of a fenestration, C = the apical border, D = root apex point

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The root fenestrations were categorized according to Davies et al.,[10] Yoshioka et al.,[11] and Pan et al.,[17] into the following six types [Figure 2]:
Figure 2: Types of root fenestrations according to Pan et al. (2014)

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  • Type I: Fenestration on the apical one-third of the root
  • Type II: Fenestration on the middle one-third of the root
  • Type III: Fenestration on the coronal one-third of the root but no involvement of the alveolar margin
  • Type IV: Fenestration on the apical and middle parts of the root
  • Type V: Fenestration on the middle and coronal part of the root but excluding the alveolar margin
  • Type VI: Fenestration on the whole root but excluding the alveolar margin.


Statistical analysis

The data analyzes are carried out using the Statistical Package for the Social Sciences (SPSS) version 20?. Descriptive statistics have been performed. Chi-square test and one-way ANOVA were conducted to measure statistical inferences, as P = 0.05 was considered statistically significant. To measure multiple mean differences, post hoc analyses were performed using the Tukey HSD test and normality by Shapiro–Wilk test.


  Results Top


Descriptive statistics and data visualization

Eighty patients of 100 cases have fenestration in 2–3 teeth giving an overall 80% prevalence of tooth fenestration.

[Table 1] shows the relationship of gender to age group. The majority of patients affected by root fenestration were female (57.5%) and the most common tooth being affected was tooth #12 (maxillary right lateral incisor) (35.0%) as well as #13 (maxillary right canine) (28.7%), while the least was tooth #22 (maxillary left lateral incisor (10.0%). No fenestration was detected on the right maxillary central incisors (#11). In addition, the most common type of root fenestration was Type IV (52.5%), followed by Type I (27.5%) and Type II (15%). The overall mean distribution of root (A–D), fenestration at (A–B) and (B–C) were further described in Table 1.
Table 1: Characteristics of patients with root fenestration according to age group (n=80)

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The relationship between fenestration type and age groups are shown in [Table 1]. It was found that there was no significant difference between all types of fenestrations and any age groups (P < 0.365).

Regarding the relationship of root length (A-D) with each age group, there was no statistical difference with any age group (P < 0.685). It was also showed no statistical difference with any age group (P < 0.133) in relation to fenestration (A-B) and (B-C) (P < 0.4720).

There was a significant difference in tooth #21 in both age intervals (31-40) years and (41-50) years where P < 0.034. Another tooth #22 showed a significant difference in group intervals (31-40) years and (>50 years) where P < 0.034. Finally, tooth # 23 showed a significant difference in group intervals (41-50) years and (>50 years) where P < 0.04.

[Table 2] shows the relationship of root length, fenestration at (A-B), and (B-C) and that with tooth numbers. It was shown that there was a statistically significant of root length with all of the anterior teeth with P < 0.001. Furthermore, there was a statistical significant of fenestration at (B-C) with all anterior teeth (P < 0.028). On the other hand, there was no statistical significant of fenestration at (A-B) with any tooth (P < 0.175).
Table 2: Comparison between the measurement of root length, fenestration (A-B), fenestration (B-C) and tooth number (n=80)

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[Table 3] shows the mean differences of fenestration at (A-B) and (B-C) in relation to tooth number. There was statistical difference in relation to tooth #22 (P < 0.042) and tooth #12 where P < 0.042.
Table 3: Multiple mean differences of the measurement of fenestration (A-B) and fenestration (B-C) in regards to tooth number (n=80)

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[Figure 3] shows fenestration at (A-B) in each tooth number of all teeth. The highest mean was found in relation to tooth #13 (8.9 mm) and lowest was in tooth # 23 (maxillary left canine) (6.9 mm).
Figure 3: Mean comparison of FEN (A.B) between each tooth number. FEN = root fenestration

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Fenestration at (B-C) was shown in each tooth number [Figure 4]. The highest mean was found in relation to tooth #23 (7.1 mm) and lowest in tooth #12 (4.9 mm).
Figure 4: Mean comparison of FEN (B.C) between each tooth number. FEN = root fenestration

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[Figure 5] shows the fenestration type in relation to gender. It was found that Type II fenestration was high among females (83.3%), while Type IV was the lowest (42.9%). On the other hand, Type IV was high among males (57.1%), whereas Type II was the lowest (16.7%).
Figure 5: Comparison between gender and root fenestration type

Click here to view



  Discussion Top


Throughout Saudi populations, the appearance of teeth and the precise anatomy of the root canal vary from those seen in many cultural groups.[10] Cone beam computed tomography scans were used in this study. It allows surgeons to visualize alveolar bone in human patients in three-dimensions. The buccal and lingual surfaces are visible on CBCT scans, which provide information that is unavailable on periapical or panoramic radiographs. This information, if noticed before a surgical procedure, can provide valuable information on the presence and degree of severity of the bone defects. This study was limited to root fenestrations and excluded dehiscences because of the ambiguity in the definition and means of detection of dehiscences.

Only the maxillary anterior teeth were evaluated for this study. The frequency of fenestrations was most commonly detected in the anterior regions. Braut et al.[4] and Larato[18],[19] reported that the defects are more predominant in the anterior region compared to posterior. These facts were taken into consideration when designing the current study. In addition, the time required for observing root fenestrations using CBCT is considerably longer than that required for observing and taking measurements in human skulls. In the latter method, the facial surfaces of the skulls can be viewed relatively quickly, and the presence of fenestrations can be documented. However, when CBCT scans were used to view fenestrations, there was a significant increase in time that has to be allotted for each tooth. For the reasons listed above, this study was limited to the facial surfaces of the maxillary anterior teeth.

Fenestrations were more commonly found in the buccal alveolar plate of maxillary first molar and canine due to thin bone. It is very seldom to occur on the lingual side. Edel et al. noted two fenestrations on the lingual root surfaces out of 990 examined teeth. They were associated with lingually inclined roots of the mandibular incisors.[7] Rupprecht et al. detected only 3.9% of all fenestrations of 3315 examined teeth on the lingual surfaces of the mandibular anterior teeth.[20] The present study was limited to facial root fenestrations because of the low prevalence of lingual (palatal) fenestrations reported in the literature. The most common tooth being affected by fenestration in the current study was tooth #12 (right lateral incisor) (35.0%), as well as tooth #13 (right canine) (28.7%).

Davies et al., Rupprecht et al., and Larato recorded the fenestration rate of the teeth, in general, decreasing with age.[10],[18],[19],[20] This observation was attributed to increased tooth loss with age due to bone loss caused by periodontitis, endodontic pathosis, or trauma. In the current study, both age groups of (31–40), (41–50), and (>50) years showed a higher prevalence of root fenestration compared to other age groups. This is due to the long-term impact of local factors (e.g., plaque accumulation, patient manipulation of affected sites), fenestrations that evolve into dehiscence or other forms of bone defects, which are not known as fenestration. Finally, elderly patient was so more suggest to have extracted, especially teeth with bone deficiencies like fenestrations.

Yoshioka et al. categorized apical fenestration into three subcategories based on apical foramen involvement.[11] However, the deviation of morphological forms, and root apex positions and major apical foramen is common, and this variant frequency varies with age and tooth direction.[21],[22] Treatment options cannot, therefore, be drawn up solely based on whether the apical foramen or the tooth apex protrudes from the alveolar bone.

Six types of fenestrations reported by Pan et al.[17] were classified based on their location and size was used in the present study, which can be useful to establish appropriate treatment planning. Fenestration classification was not used by previously published case reports, so detailed fenestration data such as size and location were not usable. In addition, root resection, tissue regeneration, and bone regeneration have been included in many cases.[9],[15],[23],[24] Although root resection may be improper in Type II, III, and V fenestration, while the residual root may be too short to work just after surgery in Type IV fenestration. Since there is no standardized fenestration treatment guideline, some thoughts need to be provided on how to best handle the different types and levels. In the present study, the most common type of root fenestration was Type IV (52.5%), followed by Type I (27.5%) and Type II (15%), whereas the least of them was Type VI.

Most studies found that the prevalence of root fenestration was not differed by gender. In the current study, it was found that Type II fenestration was high among females (83.3%), while Type IV was the lowest (42.9%). The present study consistent with Rupprecht et al.[20] and Ozcan and Sekerci.[25]

Although there have been many historical studies reporting the prevalence and frequency of alveolar bone defects, few have actually reported the measurements of these defects. Rupprecht et al. reported the mean height and width of root fenestrations in a population of modern American skulls to be 3.6 ± 1.8 × 2.1 ± 0.7 mm.[20] The mean measurements of fenestrations were slightly smaller than that of dehiscences (5.9 ± 2.4 × 3.3 ± 1.3 mm). In the present study, the average length of the fenestrations was measured (6 mm). In the sagittal CBCT view, which was used to measure the length of the fenestrations, it was not possible to measure the width as well.

Depending on the type of periodontal surgery that is performed, the location of the fenestration may be hazardous. For example, if an osseous surgery is performed and the fenestration is located in the coronal third of the tooth, the amount of ostectomy and osteoplasty that can be achieved will be greatly limited and may affect the outcome of the procedure. It may be impossible to obtain positive architecture without jeopardizing the affected tooth or adjacent teeth. In the study of Edel et al., the severity of the root fenestration was not classified, but the location (apical or coronal halves of the root) was estimated. They reported that the majority of fenestrations were located in the apical half of the root.[7] For this reason, the average tooth length, as shown by Ingle, was considered indicative of each specific tooth, and the root length was determined by subtracting the crown length from the overall tooth length.[26]

Research on the efficiency and image quality of CBCT has been limited to determine bone morphology. There has also been no research investigating the use of CBCT to test in vivo alveolar bone morphology, as the present study does. Instead, most studies used artificially created defects on phantoms or dry skulls, which do not accurately represent some anatomic structures such as tooth sockets and alveolar bone margins. The difficulty with assessing artificially created defects on dry skulls is that the detection of defects can be overestimated due to the operator's distinct boundaries.[27] Misch et al. conducted a study to compare CBCT measurements of periodontal defects to traditional methods.[28] Artificial osseous defects, including infrabony facial, palatal, and proximally defects of varying width and height, were created on mandibles of dry skulls. CBCT scanning, periapical radiography, and direct measurements using a periodontal probe were compared to an electronic caliper that was used as a standard reference. For radiographs, most buccal and lingual measures could not be performed; however, all bony deficiencies were directly or with CBCT identifiable and measurable. The results of this study are evidence that CBCT is as accurate as direct measurements using a probe and as reliable as radiographs for interproximal areas.


  Conclusions Top


In Saudi subpopulation, the majority of patients affected by root fenestration were females, and the most common tooth being affected was right lateral incisor. In addition, the most common type of fenestration was Type IV.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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[PUBMED]  [Full text]  
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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