Article_4_v5_1
Generated from PDF: /home/opencode/cpanel/stomaeduj_hacked/uploads/2018/01/Article_4_v5_1.pdf
ORTHODONTICS
ARE DENTAL MEASUREMENTS TAKEN ON PLASTER CASTS COMPARABLE TO THOSE
Original Article
TAKEN FROM CBCT IMAGES AND LASER SCANNED SURFACES?
Luca Pisoni1a, Marina Codari2b, Simone Galli1c, Francesca M.E. Rusconi1d, Gianluca Martino Tartaglia1e, Valentina Pucciarelli1f,
Chiarella Sforza1g*
1
LAFAS, Laboratory of Functional Anatomy of the Stomatognathic System, Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
2
Unit of Radiology, IRCCS Policlinico San Donato, Via Morandi 30, San Donato Milanese, 20097 Milan, Italy.
a,e
DDS, PhD
b
MSBE, PhD
c
CDT
d
DDS
f
MBiothec, PhD
g
MD, PhD, Head
ABSTRACT DOI: 10.25241/stomaeduj.2018.5(1).art.4
Introduction: Intraoral scanning techniques, laser scans and cone-beam computed OPEN ACCESS This is an
tomography (CBCT) are becoming widely diffused in dental practice. These instruments Open Access article under the CC
BY-NC 4.0 license.
can replace dental plaster casts with digital models; recent investigations have found that
Peer-Reviewed Article
measurements taken on digital models do not differ clinically from those obtained on
CBCT scans and physical models, but only intra-examiner reliability has been assessed. In Citation: Pisoni L, Codari M, Galli S,
Rusconi FME, Tartaglia GM, Pucciarelli
the current study we tested both intra- and inter-examiner variations, together with inter- V, Sforza C. Are dental measurements
techniques reliability. taken on plaster casts comparable to
those taken from CBCT images and
Methodology: Data from six adult subjects were retrospectively obtained. Twelve dental laser scanned surfaces? Stoma Edu J.
2018;5(1):38-42.
distances were measured on dental plaster casts using a digital calliper; on digital 3D CBCT
images using inVivoDental software (Anatomage, San Jose, CA); and on laser scanned Academic Editor: Lidia Boboc, DDS,
PhD, Associate Professor, “Carol Davila”
surfaces using Mirror Vectra Software (Canfield Scientific, Fairfield, NJ). Two different University of Medicine and Pharmacy
operators performed all measurements twice. Bland-Altman analysis, Kruskal-Wallis and Bucharest, Romania
Wilcoxon tests were used for comparisons. Received: December 23, 2017
Results: The intra- and inter-operator biases range was 0-0.34 mm. The reproducibility range Revised: February 09, 2018
Acccepted: March 01, 2018
was 72-99%. The three different techniques gave very similar measurements, with biases Published: March 03, 2018
between ±0.1 mm. Reproducibility ranged between 90 and 100%; the best reproducibility *Corresponding author: Professor
coefficients were found between plaster and digital casts, and only three differences were Chiarella Sforza, MD, PhD, Head
Department of Biomedical Sciences
larger than 0.5 mm. Calliper measurements slightly overestimated digital casts values. Only for Health, University of Milan, Milan,
the mesiodistal distance of tooth 24 (p=0.002) was significantly different among techniques. Italyvia Mangiagalli 31, I-20133 Milano,
Italy Tel: +39 – 02 503 15385, Fax:
Conclusion: Measurements on digital dental models and CBCT reconstructions of the dental +39 – 02 503 15387, e-mail: chiarella.
arches seem clinically reliable as direct calliper measurements. The inter- and intra-operator sforza@unimi.it
reliabilities were acceptable, some more care may be needed for CBCT measurements. Copyright: © 2018 the Editorial Coun-
Keywords: teeth, laser scan, cone beam computerised tomography. cil for the Stomatology Edu Journal.
1. Introduction skulls with conventional digital callipers [16, 17].
New technologies like scanning techniques, cone- Safety, accuracy and reliability of measurements taken
beam computerised tomography (CBCT) and three with new instruments must be evaluated and compared
dimensional imaging are becoming more and more with those obtained with traditional methods also for
used in all branches of dental practice (conservative, dental landmarks: data obtained from both the digital
prosthodontics, surgery and orthodontics). Among the and traditional plaster casts models must match in
other applications, these devices can replace dental order to allow using the new technologies in clinical
plaster casts with digital models possessing several practice [2, 8, 18].
advantages: easy storage, no necessary physical space, In general, recent investigations found that
no damages during handling, and easy data share with measurements taken on digital models do not differ
other professionals [1-9]. clinically from those obtained on CBCT scans and
CBCT, in particular, gives a 3D representation of the physical models [4, 5]. Unfortunately, while reporting
cranio-facial and dental structures and has already intra-examiner reliability, no inter-examiner variations
several indications in clinical routine: oral and were presented [6-8]. Indeed, the assessment of inter-
maxillofacial surgery (orthognathic surgery, treatment of operator variations seems to be of relevance in the
traumas and malignancies, nerve tracing in cases of third current scenario where dental technicians often work
molar extraction and implant placement), endodontics in centralised locations at distance from clinical offices,
(root fracture detection), orthodontics (diagnosis and and several of them may be involved in the evaluation
treatment planning) [6, 10-15]. In this last field, several of the same dental reproductions.
studies have successfully compared the accuracy of In the current study, we compared measurements
craniofacial measurements taken using landmarks taken on digital models obtained from CBCT images
identified on CBCT scans with those taken directly on and laser scanned surfaces with direct measurements
38 Stoma Edu J. 2018;5(1): 38-42 http://www.stomaeduj.com
ARE DENTAL MEASUREMENTS TAKEN ON PLASTER CASTS COMPARABLE TO THOSE
TAKEN FROM CBCT IMAGES AND LASER SCANNED SURFACES?
obtained on dental plaster casts. Both intra- and inter-
Original Article
operator reliabilities were assessed.
2. Material and methods
Data from six adult Caucasian subjects with full
dentition, no implant surgery, dental fillings, prostheses
or caries that could affect the morphology of teeth
were obtained. The absence of implants and metal
fillings was selected as inclusion criterion to reduce
the presence of metal artefacts that can alter the
measurement process.
All patients were retrospectively selected from a clinical
database and underwent CBCT examination for clinical
reasons uncorrelated with this study. Their plaster casts
poured from alginate impressions, cast in gypsum and
conventionally trimmed, were collected as well. They
reproduced the full arches with no surface damage. The Figure 1. Dental crown distances chosen for the study in the right side
casts were imaged by a laser scan (iSeries, Dental Wings, mandibular arch. The corresponding distances were selected also in the
Montreal, Canada), and their 3D digital models obtained [1]. left side maxillary arch: a) Mesiodistal distance of tooth 41; b) Mesiodistal
The work described was carried out in accordance with distance of tooth 43; c) Mesiodistal distance of tooth 44; d) Mesiodistal dis-
The Code of Ethics of the World Medical Association tance of tooth 46; e) Distance from vestibular to lingual cusp of tooth 44; f)
Distance from mesial-vestibular to mesial-lingual cusp of tooth 46.
(Declaration of Helsinki). Informed consent was
obtained from all patients, and their privacy rights
observed. Considering the retrospective nature of the
study, no ethical approval was required. No clinical
information was retrieved from the database.
Twelve dental distances (Fig. 1) were measured on dental
plaster casts using a digital calliper; on digital 3D CBCT
images using inVivoDental software (Anatomage, San
Jose, CA); and on laser scanned surfaces using Mirror®
Vectra Software (Canfield Scientific, Fairfield, NJ).
Two different operators performed all measurements
twice. A previous calibration session was performed:
each operator made the whole set of measurements on
a dental plaster cast and on its digital reproduction, as
well as on the CBCT images of a patient not included in Figure 2. Mean differences between measurement methods. MD: Me-
the study. The results were discussed until a consensus siodistal distance; VL or VP: vestibulolingual or vestibulopalatal distance. *:
P = 0.002, Kruskal-Wallis test.
about landmark location was obtained.
Intra- and inter-operator reliability was assessed by the best for plaster casts (all larger than 93%). The intra-
Bland-Altman analysis, and for each comparison both and inter-operator reliabilities were comparable.
the reproducibility coefficient and the bias (difference The three different techniques gave very similar
between measurements divided by the mean value) measurements, with biases smaller than ±0.1
were calculated [7, 18]. mm, except the calliper-CBCT comparisons of the
The mean values were computed separately for tooth mesiodistal diameters of teeth 41 and 24 (Table 2).
and measurement (mesiodistal and vestibulopalatal or Reproducibility ranged between 90 and 100%; the
vestibulolingual crown diameters). The three different comparisons between plaster and digital casts had the
techniques were compared by Bland-Altman analysis best reproducibility coefficients (all larger than 97%).
and Kruskal-Wallis test, with the Wilcoxon test for post- The mean differences (± 1 SD) for calliper-digital,
hoc comparisons. digital-CBCT and calliper-CBCT measurements were
For all tests, the statistical significance level was set to respectively 0.09±0.14, 0±0.3, 0.09±0.37 mm (Fig. 2).
p < 0.01, with the Bonferroni correction for post-hoc Only three differences were larger than 0.5 mm, which
comparisons. represents the threshold for clinical acceptability [7,
18]: calliper-CBCT for teeth 41 and 24, and digital-CBCT
for tooth 24 (all mesiodistal crown diameter). Calliper
3. Results measurements slightly overestimated digital cast
The intra- and inter-operator biases ranged between 0 values, while the other differences were more scattered.
and 0.34 mm, and only 3/72 biases were equal to larger Only the mesiodistal distance of tooth 24 (Kruskal-
than |0.3| mm (Table 1). These biases were observed for Wallis test, p = 0.002) was significantly different among
the vestibulopalatal diameters of teeth 24 and 26 (intra- techniques (Table 3).
operator analysis), and the vestibulopalatal diameter of
tooth 26 (inter-operator analysis). Reproducibility ranged
between 72 and 99%, the worst coefficients were found 4. Discussion
for CBCT measurements (18/24 were lower than 90%), In the present investigation, we compared dental
Stomatology Edu Journal 39
ARE DENTAL MEASUREMENTS TAKEN ON PLASTER CASTS COMPARABLE TO THOSE
TAKEN FROM CBCT IMAGES AND LASER SCANNED SURFACES?
Original Article Table 1. Intra- and inter-operator repeatability (Bland-Altman analysis).
Intraoperator Interoperators
Central First First First First Central First First First First
Canine Canine
incisor premolar molar premolar molar incisor premolar molar premolar molar
Vestibulopalatal/ Vestibulopalatal/
Hemiarch Mesiodistal Mesiodistal
Vestibulolingual Vestibulolingual
Left maxillary
Calliper Bias 0.07 0.02 0.04 0.01 0.01 0.07 0.03 0.02 0.03 0.03 0.04 0.03
Reproducibility 96 95 95 99 95 97 98 99 97 99 98 95
Digital Bias 0.03 0.13 0.14 0.05 0.00 0.23 0.04 0.06 0.20 0.16 0.16 0.21
Reproducibility 96 95 95 93 94 95 98 94 95 98 94 97
CBCT Bias 0.06 0.22 0.21 0.16 0.30 0.30 0.05 0.12 0.19 0.12 0.03 0.34
Reproducibility 91 87 83 87 78 78 91 90 94 80 75 72
Right mandibular
Calliper Bias 0.02 0.00 0.04 0.06 0.03 0.04 0.05 0.03 0.06 0.05 0.04 0.07
Reproducibility 96 97 98 96 93 95 96 98 97 98 97 94
Digital Bias 0.08 0.28 0.06 0.14 0.02 0.13 0.00 0.26 0.28 0.08 0.25 0.01
Reproducibility 98 88 93 96 90 81 97 94 89 94 94 89
CBCT Bias 0.10 0.06 0.04 0.20 0.04 0.21 0.10 0.25 0.24 0.04 0.09 0.10
Reproducibility 87 93 86 89 87 75 72 94 90 94 82 82
Bias values (absolute values) are in mm, reproducibility coefficients are in %
Table 2. Bland-Altman analysis for the three measurement methods.
Central First First
Canine First premolar First molar
incisor premolar molar
Hemiarch Mesiodistal Vestibulopalatal/ Vestibulolingual
Left maxillary
Calliper - Digital Bias 0.00 0.02 -0.02 0.00 0.05 0.04
Reproducibility 100 100 99 100 99 99
Digital – CBCT Bias 0.05 0.00 -0.08 -0.02 0.02 -0.01
Reproducibility 99 99 99 99 98 95
Calliper - CBCT Bias 0.06 0.02 -0.10 -0.02 0.07 0.03
Reproducibility 99 99 99 99 98 95
Right mandibular
Calliper - Digital Bias 0.02 -0.01 0.03 -0.01 0.01 0.04
Reproducibility 99 99 99 100 98 98
Digital – CBCT Bias 0.08 0.05 -0.03 -0.03 -0.02 0.02
Reproducibility 97 98 98 99 91 97
Calliper - CBCT Bias 0.10 0.04 0.00 -0.04 -0.01 0.06
Reproducibility 97 98 98 99 90 96
Bias values (absolute values) are in mm, reproducibility coefficients are in %
linear distances (crown dimensions) taken with three intra- and inter-operator variabilities. Indeed, the
different techniques. Overall, differences among the quantification of inter-operator reliability is necessary
measurements were limited, and their reproducibility whenever multiple operators contribute to the analysis
very high, ranging between 90 and 100%. Together of the same dental reproductions. The good agreement
with the comparison among methods, we investigated between our two operators may be an effect of their
the variability inherent to each measurement protocol, prior calibration, which should be included in all
namely the effect of repeated measurements made measurement protocols [12].
by the same and different operators. We found limited Apparently, this is the first study that reported inter-
40 Stoma Edu J. 2018;5(1): 38-42 http://www.stomaeduj.com
ARE DENTAL MEASUREMENTS TAKEN ON PLASTER CASTS COMPARABLE TO THOSE
TAKEN FROM CBCT IMAGES AND LASER SCANNED SURFACES?
operator differences: for instance, both White et al. [19] Table 3. P values from Kruskal-Wallis test.
Original Article
and El-Zanaty et al. [20] assessed only intra-examiner Central First First First First
Canine
bias. Indeed, two or three different operators were incisor premolar molar premolar molar
involved in other studies, but only intra-operator Hemiarch Mesiodistal Vestibulopalatal
variability was reported [6]. Similarly, Wiranto et al. [8] Left
0.09 0.93 0.002* 0.93 0.18 0.47
assessed the variability from three different operators, maxillary
but did not report the actual inter-operator data, Right
0.05 0.55 0.86 0.36 0.93 0.44
quoting a previous investigation. mandibular
The excellent reproducibility of the three different *Significant difference p < 0.01. For significant values, post hoc Wilcoxon tests:
measurement techniques is in line with the current Calliper – CBCT: p = 0.002; Digital - CBCT: p = 0.03.
literature reports. For instance, De Luca Canto et al. were acceptable, while more care may be needed for
[2] made an extensive review to study the validity of CBCT measurements, as also underlined by previous
measurements obtained from digital dental models studies [3, 4].
produced from laser scanning against those directly The results are promising, nevertheless further
made on the original physical dental models. The evaluations on a larger sample are advised.
authors concluded that the current scientific evidence
supports the validity of digital measurements.
White et al. [19] tested the accuracy of the digital Author Contributions
reproductions of dental models made by using CBCT LP: design of the study, data collection and
scans, and found satisfactory values for intra-arch interpretation, drafting the MS, final approval of the
measurements but inaccurate inter-arch relationships. MS; MC: design of the study, data elaboration, drafting
El-Zanaty et al. [20] compared linear distances obtained the MS, final approval of the MS; SG: data collection,
on plaster casts and from CT head scans; the two critical review of the MS, final approval of the MS; FMER:
techniques had excellent agreement. More recent data collection and elaboration, critical review of the
studies reported that both intraoral scanning and MS, final approval of the MS; GMT: design of the study,
CBCT scanning of alginate impressions of the dental data elaboration and interpretation, critical review of
arches gave valid, reliable, and reproducible dental the MS, final approval of the MS; VP: design of the study,
measurements for diagnostic purposes. data collection, drafting the MS, final approval of the
Wiranto et al. [8] compared traditional plaster scans, MS; CS: design of the study, data interpretation, critical
scans obtained from intraoral scans, and CBCT scans review of the MS, final approval of the MS.
of alginate impressions, and found that the digital
reproduction of dental arches can be usefully employed
for diagnostic purposes. Acknowledgments
In the current study, the worst coefficients of Not applicable. The study was self-funded. There are
reproducibility were found for CBCT measurements, while no conflicts of interest and no financial interests to be
the best were those obtained for plaster casts. For CBCT, disclosed.
similar data were reported by Kim et al. [4, 5]. Literature
is not in agreement about the technique with the best
reproducibility: both digital models [4, 5, 7], and plaster References
models [16] had the best scores in different studies. 1. Codari M, Pucciarelli V, Pisoni L, et al. Laser scanner compared
Overall, only three mesiodistal crown diameters had with stereophotogrammetry for measurements of area on nasal
plaster casts. Br J Oral Maxillofac Surg. 2015;53(8):769-770. doi:
differences larger than 0.5 mm, which is considered the 10.1016/j.bjoms.2015.05.007.
threshold for clinical acceptability [7, 18]. This corresponds [Full text links] [PubMed] Google Scholar(4) Scopus(1)
to 8% of the analysed dental distances (3 out of 12 2. De Luca Canto G, Pachêco-Pereira C, Lagravere MO, et al. Intra-
arch dimensional measurement validity of laser-scanned digital
distances x 3 techniques values), a value larger than that dental models compared with the original plaster models: a
reported by Tarazona-Álvarez et al. [6] who found only systematic review. Orthod Craniofac Res. 2015;18(2):65-76. doi:
10.1111/ocr.12068.
5% of significant differences when comparing 20 linear [Full text links] [PubMed] Google Scholar(13) Scopus(4)
distances obtained directly on dried mandibles and on 3. Kau CH, Littlefield J, Rainy N, et al. Evaluation of CBCT digital
their CBCT scans. Additionally, the current results well models and traditional models using the Little’s Index. Angle
Orthod. 2010;80(3):435-439. doi: 10.2319/083109-491.1.
confirm that measurements involving the premolars are [Full text links] [PubMed] Google Scholar(78) Scopus(41)
more variable than the other ones [4]. 4. Kim J, Heo G, Lagravère MO. Accuracy of laser-scanned models
compared to plaster models and cone-beam computed
In general, the overestimation of calliper measurements tomography. Angle Orthod. 2014;84(3):443-450. doi:
vs. digital casts data is in line with the literature reports 10.2319/051213-365.1.
[18], while the comparison with CBCT data is more [Full text links] [PubMed] Google Scholar(37) Scopus(16)
5. Kim J, Lagravére MO. Accuracy of Bolton analysis measured in
scattered. For instance, on dry mandibles, most of CBCT laser scanned digital models compared with plaster models
measurements were significantly smaller than those (gold standard) and cone-beam computer tomography
images. Korean J Orthod. 2016;46(1):13-19. doi: 10.4041/
obtained by using the calliper [6]. kjod.2016.46.1.13.
[Full text links] [Free PMC Article] [PubMed] Google Scholar(9)
Scopus(6)
6. Tarazona-Álvarez P, Romero-Millán J, Peñarrocha-Oltra D, et al.
5. Conclusion Comparative study of mandibular linear measurements obtained
In conclusion, measurements on digital dental models by cone beam computed tomography and digital calipers. J Clin
Exp Dent. 2014;6(3):e271-274. doi: 10.4317/jced.51426.
and CBCT reconstructions of the dental arches seem [Full text links] [Free PMC Article] [PubMed] Google Scholar(11)
clinically reliable as direct measurements performed on Scopus(5)
dental plaster casts. Inter- and intra-operator reliability 7. Wan Hassan WN, Othman SA, Chan CS, et al. Assessing
agreement in measurements of orthodontic study models:
Stomatology Edu Journal 41
ARE DENTAL MEASUREMENTS TAKEN ON PLASTER CASTS COMPARABLE TO THOSE
TAKEN FROM CBCT IMAGES AND LASER SCANNED SURFACES?
Digital caliper on plaster models vs 3-dimensional software 14. Horner K, Jacobs R, Schulze R. Dental CBCT equipment and
Original Article on models scanned by structured-light scanner. Am J Orthod performance issues. Radiat Prot Dosimetry. 2013;153(2):212-218.
Dentofacial Orthop. 2016;150(5):886-895. doi:10.1016/j. [Full text links] [PubMed] Google Scholar(26) Scopus(12)
ajodo.2016.04.021. 15. Shaheen E, Politis C. The use of 3D virtual planning and
[Full text links] [PubMed] Google Scholar(2) Scopus(1) 3D printing for the treatment of facial asymmetry: a case
8. Wiranto MG, Engelbrecht WP, Tutein Nolthenius HE, et al. report. Stoma Edu J. 2016;3(3-4):156-161. doi: 10.25241/
Validity, reliability, and reproducibility of linear measurements stomaeduj.2016.3(3-4).art.4.
on digital models obtained from intraoral and cone-beam 16. Berco M, Rigali PH Jr, Miner RM, et al. Accuracy and reliability
computed tomography scans of alginate impressions. Am J of linear cephalometric measurements from cone-beam
Orthod Dentofacial Orthop. 2013;143(1):140-147. doi: 10.1016/j. computed tomography scans of a dry human skull. Am J Orthod
ajodo.2012.06.018. Dentofacial Orthop. 2009;136:17e1-e9; discussion 17-18. doi:
[Full text links] [PubMed] Google Scholar(96) Scopus(49) 10.1016/j.ajodo.2008.08.021.
9. Gibelli DM, Pucciarelli V, Pisoni L, et al. Quantification of dental [Full text links] [PubMed] Google Scholar(200) Scopus(87)
movements in orthodontic follow-up: a novel approach based 17. Periago DR, Scarfe WC, Moshiri M, et al. Linear accuracy
on registration of 3D models of dental casts. Stoma Edu J. and reliability of cone beam CT derived 3-dimensional
2017;4(1):55-61. doi: 10.25241/stomaeduj.2017.4(1).art.5. images constructed using an orthodontic volumetric
10. Asgary S, Nikneshan S, Akbarzadeh-Bagheban A, et rendering program. Angle Orthod. 2008;78(3):387-395. doi:
al. Evaluation of diagnostic accuracy and dimensional 10.2319/122106-52.1.
measurements by using CBCT in mandibular first molars. J Clin [Full text links] [PubMed] Google Scholar(322) Scopus(159)
Exp Dent. 2016;8(1):e1-8. doi: 10.4317/jced.52570. 18. Radeke J, von der Wense C, Lapatki BG. Comparison of orthodontic
[Full text links] [Free PMC Article] [PubMed] Google Scholar(1) measurements on dental plaster casts and 3D scans. J Orofac
Scopus(1) Orthop. 2014;75(4):264-274. doi:10.1007/s00056-014-0217-9.
11. Codari M, Pucciarelli V, Tommasi DG, et al. Validation of a [Full text links] [PubMed] Google Scholar(14) Scopus(6)
technique for integration of a digital dental model into 19. White AJ, Fallis DW, Vandewalle KS. Analysis of intra-arch and
stereophotogrammetric images of the face using cone- interarch measurements from digital models with 2 impression
beam computed tomographic data. Br J Oral Maxillofac Surg. materials and a modeling process based on cone-beam
2016;54(5):584-586. doi: 10.1016/j.bjoms.2016.01.019. computed tomography. Am J Orthod Dentofacial Orthop.
[Full text links] [PubMed] Google Scholar(2) Scopus(0) 2010;137(4):456.e1-9; discussion 456-457. doi: 10.1016/j.
12. Codari M, Caffini M, Tartaglia GM, et al. Computer-aided ajodo.2009.09.019.
cephalometric landmark annotation for CBCT data. Int J Comput [Full text links] [PubMed] Google Scholar(55) Scopus(27)
Assist Radiol Surg. 2017;12:113-121. doi: 10.1007/s11548-016-1453-9. 20. El-Zanaty HM, El-Beialy AR, Abou El-Ezz AM, et al. Three-
[Full text links] [PubMed] Google Scholar(2) Scopus(1) dimensional dental measurements: An alternative to plaster
13. De Angelis D, Gibelli D, Gaudio D, et al. Sexual dimorphism of models. Am J Orthod Dentofacial Orthop. 2010;137(2):259-265.
canine volume: a pilot study. Leg Med (Tokyo). 2015;17(3):163- doi: 10.1016/j.ajodo.2008.04.030.
146. doi:10.1016/j.legalmed.2014.12.006. [Full text links] [PubMed] Google Scholar(71) Scopus(30)
[PubMed] Google Scholar(13) Scopus(5)
Luca PISONI
DDS, PhD
LAFAS, Laboratory of Functional Anatomy of the Stomatognathic System
Department of Biomedical Sciences for Health, University of Milan
Milano, Italy
CV
Luca Pisoni, DDS, PhD, is currently a member of the research staff in the Laboratory of Functional Anatomy of the Stomatognathic
System - LAFAS, Department of Biomedical Sciences for Health at the University of Milan, Milan, Italy. His fields of research are
the morphological and metrical assessment of anatomical characteristics of craniofacial structures, dental arches, and teeth,
including their modifications with age, sex and pathology. He authored/co-authored some papers published in international,
peer reviewed Journals. He is also in private practice in Legnano (Milan, Italy).
Questions
1. Which instruments can be used to obtain a 3D virtual model of dental arches?
qa. Bite wing radiographs;
qb. Ultrasounds;
qc. Laser scans;
qd. Conventional orthopantomographs.
2. Which instruments can be used to obtain a 3D virtual model of dental roots?
qa. Laser scans;
qb. Cone Beam Computerized Tomography (CBCT);
qc. Teleradiographs;
qd. Surface EMG.
3. In the current study we assessed
qa. Three different methods to measure dental diameters;
qb. The effect of operator experience in making dental measurements;
qc. The use of Magnetic Resonance to measure dental diameters;
qd. Dental arch diameters in fully edentulous patients.
4. In the current study, we found that
qa. Intra-operator error was larger than 20%;
qb. Measurements on the ultrasound reconstructions of the dental arches were clinically useful;
qc. Measurements on the laser scanned reconstructions of the dental arches were too prone to error;
qd. Measurements on the CBCT reconstructions of the dental arches were clinically reliable.
42 Stoma Edu J. 2018;5(1): 38-42 http://www.stomaeduj.com