Comparative study of mandibular linear measurements obtained by cone beam computed tomography and digital calipers

Abstract

Objectives: Cone beam computed tomography (CBCT) is an innovative dental of imaging system characterized by rapid volumetric imaging with patient exposure to a single dose of radiation. The present study was carried out to compare the linear measurements obtained with CBCT and digital caliper in 20 mandibles from human cadavers. Study design: A total of 4800 linear measurements were measured between different mandibular anatomical points with CBCT and digital caliper. The real measurements were defined as those obtained with the digital caliper. Posteriorly, the mandibles were scanned to obtain the CBCT images, with software-based measurements of the distances. Results: The measurements obtained with the digital caliper were greater. The CBCT technique underestimated distances greater than 100 mm. Conclusions: CBCT allows to obtain linear mandibular anatomical measurements equivalent to those obtained with digital caliper. The differences existing between both methods were clinically acceptable. Key words:Computed tomography, cone beam CT, accuracy, reliability, digital caliper.

Are Dental Measurements Taken on Plaster Casts Comparable to Those Taken From CBCT Images and Laser Scanned Surfaces?

“…Overall, only three mesiodistal crown diameters had differences larger than 0.5 mm, which is considered the threshold for clinical acceptability [7,18]. This corresponds to 8% of the analysed dental distances (3 out of 12 distances x 3 techniques values), a value larger than that reported by Tarazona-Álvarez et al [6] who found only 5% of significant differences when comparing 20 linear distances obtained directly on dried mandibles and on their CBCT scans. Additionally, the current results well confirm that measurements involving the premolars are more variable than the other ones [4].…”

“…In general, the overestimation of calliper measurements vs. digital casts data is in line with the literature reports [18], while the comparison with CBCT data is more scattered. For instance, on dry mandibles, most of CBCT measurements were significantly smaller than those obtained by using the calliper [6].…”

“…Indeed, two or three different operators were involved in other studies, but only intra-operator variability was reported [6]. Similarly, Wiranto et al…”

“…In general, recent investigations found that measurements taken on digital models do not differ clinically from those obtained on CBCT scans and physical models [4,5]. Unfortunately, while reporting intra-examiner reliability, no inter-examiner variations were presented [6][7][8]. Indeed, the assessment of interoperator variations seems to be of relevance in the current scenario where dental technicians often work in centralised locations at distance from clinical offices, and several of them may be involved in the evaluation of the same dental reproductions.…”

“…Among the other applications, these devices can replace dental plaster casts with digital models possessing several advantages: easy storage, no necessary physical space, no damages during handling, and easy data share with other professionals [1][2][3][4][5][6][7][8][9]. CBCT, in particular, gives a 3D representation of the cranio-facial and dental structures and has already several indications in clinical routine: oral and maxillofacial surgery (orthognathic surgery, treatment of traumas and malignancies, nerve tracing in cases of third molar extraction and implant placement), endodontics (root fracture detection), orthodontics (diagnosis and treatment planning) [6,[10][11][12][13][14][15]. In this last field, several studies have successfully compared the accuracy of craniofacial measurements taken using landmarks identified on CBCT scans with those taken directly on skulls with conventional digital callipers [16,17].…”