Prevalence and distribution of facial alveolar bone fenestrations in the anterior dentition: a cone beam computed tomography analysis

UnrestrictedCone beam computed tomography scans can provide valuable information to dental surgeons. This information can help to alleviate the unexpected encounter of an alveolar bone defect and assist in proper treatment planning when reviewed prior to surgical procedures. Additionally, awareness of potential complications may help to optimize the success of treatment when mucogingival surgeries are performed in these areas. The objective of this study was to detect facial alveolar bone fenestrations of the anterior teeth using NewTom CBCT scans and to report the incidence and distributions of these defects. It was hypothesized that the incidence and distributions would be comparable to previously reported studies. The secondary objective was to measure and describe the vertical length of the fenestrations.; Cone beam computed tomography (CBCT) scans were consecutively selected from the USC School of Dentistry active database (Redmond Imaging Center, Los Angeles, CA). The database consisted of CBCT scans of patients who were interested in receiving orthodontic treatment, dental implant therapy, analysis of TMJ pathology, or participating in a sleep apnea study. The one hundred and twenty-five CBCT scans selected for the current study were taken between March 2009 and November 2009. Most of the CBCT scans selected provided twelve teeth for analysis, the anterior dentition (maxillary and mandibular). Scans were not included if the roots of the anterior teeth could not be visualized due to scattered images. Classifying information including the age, gender, and the reason for the scan were included for comparison purposes.; The CBCT scans were evaluated for facial alveolar bone fenestrations. When fenestrations were detected, the location was recorded using the CEJ and the root apex as a reference. The location was listed as coronal, middle, or apical. The apicocoronal length of the fenestrations were also measured and recorded.; The majority of the patients included in the present study did not have detectable fenestrations (n=96). In the remaining twenty-nine patients, fenestrations were more prevalent in females (62.1%). The twenty-nine patients provided a total of thirty-seven fenestrations for analysis. The mean age of the patients with fenestrations was slightly higher than the mean age of patients without fenestrations (25.8 years vs. 22.9 years). In general, fenestrations were more commonly found on the maxillary anterior teeth compared to the mandibular anterior teeth, with tooth #9 having the most occurrences of fenestrations, followed by #10. Twenty-two of the fenestrations were found to be located in the middle third of the root, nine in the coronal third, and six in the apical third.; The mean length of all fenestrations was 1.6mm±0.8mm. The largest fenestration measured was 3.9mm. This measurement was detected on a maxillary right lateral incisor. The smallest fenestration measured was 0.5mm. This measurement was detected on a mandibular right lateral incisor and a maxillary right canine. The overall percentage of teeth with fenestrations was 2.5%. The overall percentage of patients with fenestrations was 23%. There were three patients that had fenestrations on two teeth and two patients with fenestrations on three teeth.; This study provides clinical relevance because it introduces the novel approach of pre-surgically using CBCT images to detect alveolar bone defects, particularly fenestrations. Although CBCT scans are often unnecessary for many periodontal surgeries, it is becoming the standard of care for patients that are undergoing orthodontic therapy or receiving dental implants to have pre-operative three-dimensional scans. The presence of fenestrations can cause implant placement to be contraindicated in a particular site and orthodontic therapy may actually make the fenestration increase in size if treatment is not planned strategically. Further studies should be conducted to confirm and expand the results of the present study on anterior teeth and to determine predictability of the detection of fenestrations of posterior teeth using CBCT scans as well as measuring the length of those fenestrations