Predictive factors for alveolar fenestration and dehiscence

Fenestration and Dehiscence in Human Maxillary Alveolar Bone: An In Silico Study Using the Finite Element Method

INTRODUCTION

Fenestration and dehiscence are alveolar bone defects. Although not considered a pathology, these alveolar bone defects end up influencing dental treatment, such as surgeries, mainly periodontal, and therefore must be considered during treatment planning. However, currently, little is known about the biomechanical origin of these bone formations. The aim of the study was to use the finite element method (FEM) to test hypotheses of predictive factors for fenestrations and dehiscence in human alveolar bone.

METHODS

A FEM simulation of the action of functional, parafunctional, and orthodontic occlusal loads on the upper central incisor and upper canine was performed. For the simulation, a three-dimensional model of an adult human skull, fully dented and with intact bone structure, was constructed from computed tomography images. The buccal alveolar bone lamina was evaluated considering the calculation of equivalent stresses, as well as maximum principal stresses.

RESULTS

The action of functional and parafunctional forces on the incisal edges and the orthodontic force on the buccal face of the upper central incisor and upper canine teeth generated tensions at different levels of magnitude in the buccal bone lamina, varying in regions, at all levels of strength. Changing levels of force magnitude resulted in variations in relation to the level of deformation.

CONCLUSION

The computational simulation using the FEM was able to identify a difference in stress in the alveolar bone tissue in each of the applied forces. The difference in stresses obtained may suggest the formation of dehiscence or fenestration in the region studied.

Understanding root fenestration: A systematic scoping review of prevalence and clinical factors

The aim of this systematic scoping review is to explore the literature on root fenestration prevalence and its possible etiologic, aggravating and predisposing clinical factors. A systematic search was conducted in 5 electronic databases, by two independent reviewers, without any language and date restrictions. Forty-six full-text records were included in the study, out of which 27 were used for prevalence analysis and 42 for clinical factor analysis. The results suggest that the literature is heterogenous, with major differences in the study protocols and results' presentation, providing limited information regarding root fenestration prevalence and possible racial distribution patterns. Further documentation is also required regarding clinical parameters that may affect root fenestration's presence and severity. Despite their few limitations, retrospective cone beam computed tomography studies with high-resolution protocols, as well as open flap studies for direct observation of possible root fenestration sites, seem the most reliable methods to better comprehend its presence and possible distribution patterns.

Fenestration and dehiscence defects in maxillary anterior teeth using two classification systems

BACKGROUND

The primary objective of the study was to assess the buccal bone thickness (BT), evaluate and compare the prevalence of bone fenestration and dehiscence in anterior maxillary teeth using cone-beam computed tomography (CBCT).

METHODS

Images of 300 maxillary anterior teeth were investigated. The BT was measured at the bone crest, 3, 6 and 9 mm from the bone crest, and apical. Fenestration and dehiscence were recorded according to Yang and Pan's classification. Student's t-test and one-way ANOVA were performed for statistical analysis.

RESULTS

Fenestration and dehiscence rates were 35.66% and 20%, respectively. Type III fenestration was higher in group 3 (>65 years) (P = 0.028). Type I and IV fenestration and CII DII dehiscence were more common in canines (P > 0.05). Fenestration involving two-thirds (46.76%) and one-third (44.84%) of the root length was more common. Fenestrations involving the entire root were 8.4%. Most of the dehiscence (63.3%) involved one-third of the root length. Dehiscence involving two-thirds of the root length and the entire root was 5% and 9.95%, respectively. The coexistence of fenestration and dehiscence was 8.3%. Dehiscence on the palatal aspect was detected in 1.65% of the anterior maxilla.

CONCLUSIONS

The rate of BT ≤1 mm was 80.08%, and ≥2 mm was 3.66%. Fenestration was most common in canines. Fenestration was mostly located in the apical third, while dehiscence was mostly located in the coronal third. © 2022 Australian Dental Association.

Evaluation of facial alveolar bone thickness and fenestration of the maxillary premolars

OBJECTIVE

The objective of this study was to retrospectively investigate the facial alveolar bone (FAB) thickness and fenestration rate of maxillary first and second premolars using cone-beam computed tomography (CBCT).

DESIGN

A total of CBCT images of 66 patients were selected and 200 maxillary premolar (100 first and 100 second premolar) were included. The FAB thicknesses were measured at 1,3 and 5 mm apical to the alveolar bone peak. The prevalence of fenestration in maxillary premolars was recorded. The statistical analyses were performed.

RESULTS

The FAB thicknesses of the second premolars (1.39 mm at 1 mm, 1.42 mm at 3 mm, and 1.22 mm at 5 mm) were significantly higher than the first premolars (1.11 mm at 1 mm, 0.70 mm at 3 mm, and 0.48 mm at 5 mm) at 1, 3, and 5 mm levels (p < 0.05). The lowest prevalence (1 %) of the thickness of FAB ≥ 2 mm was in the first premolar has at 5 mm apical of the alveolar bone peak. The overall prevalence of fenestration in maxillary premolars was found as 30.5 %. There was a statistically significant difference between first and second premolars (p < 0.05).

CONCLUSION

The FAB thicknesses are lower in the first premolar than the second premolar. The lowest FAB thickness was in the first premolar at 5 mm apical of the bone crest as 0.42 mm. The prevalence of fenestration in maxillary premolars was higher in the Turkish subpopulation than in other populations. Fenestration was more common in the maxillary first premolar.

Frequency of root fenestration in a Greek subpopulation: A cone beam computed tomography clinical study

This cone beam computed tomography (CBCT) study aimed to assess the root fenestration (RF) frequency in healthy, intact teeth and analyse their features in a Greek subpopulation. 432 CBCT scans were examined. 5486 teeth were evaluated for RF prevalence. RF prevalence and distribution were recorded for each jaw, tooth group, as well as patient age and sex. RF symmetry, distribution to the affected root surface and the effects of age and sex were evaluated. The prevalence of RF ranged from 0.57% (central incisors) to 7.18% (first premolars) and from 0.48% (second premolars) to 10.79% (lateral incisors) for the maxilla and the mandible, respectively. No symmetrical occurrence of RF was detected. Most RF patients presented one or two defects in both jaws. Types I and IV were the most prevalent in the maxilla, while Types III, II and V were the most prevalent in the mandible. No statistical difference was detected between different sexes and age groups (P > 0.05).

Prevalence of and risk factors for alveolar fenestration and dehiscence in the anterior teeth of Chinese patients with skeletal Class III malocclusion

INTRODUCTION

This study investigated the prevalence of and risk factors for alveolar fenestration and dehiscence in the anterior teeth of Chinese patients with skeletal Class III malocclusion.

METHODS

This study included clinical and radiographic examinations and intraoperative observations of 460 anterior teeth from 54 patients who underwent corticotomy and periodontal regenerative surgery before orthodontic treatment. Fenestration and dehiscence were detected and recorded during open-flap surgery. Univariate and multivariate analyses were performed to assess relationships between fenestration and dehiscence and age, sex, history of previous orthodontic treatment, mandibular plane angle, dentition, tooth position, sagittal root position, periodontal biotype, gingival recession, width of keratinized gingiva, and width of the basal bone.

RESULTS

The prevalence of buccal alveolar bone defects was 16.1% (fenestration) and 20.7% (dehiscence) at the tooth level. Multivariate logistic regressions showed that fenestration was significantly associated with tooth position (canine vs central incisor, odds ratio [OR] = 3.324; P = 0.006; lateral incisor vs central incisor, OR = 5.588; P  <0.001), and sagittal root position (buccally positioned vs centrally positioned, OR = 5.865; P = 0.025). Dehiscence was significantly associated with dentition (mandible vs maxilla, OR = 11.685; P  <0.001), tooth position (canine vs central incisor, OR = 3.863; P = 0.007), age (OR = 1.227; P = 0.010), sex (male vs female, OR = 5.530; P = 0.026), and history of orthodontic treatment (yes vs no, OR = 4.773; P = 0.028).

CONCLUSIONS

Buccally positioned teeth in the osseous housing, lateral incisors, and canines were more likely to exhibit alveolar fenestration. Mandibular teeth and canines, patients who were older, were male, and had a history of orthodontic treatment, were more likely to exhibit alveolar dehiscence.