10.59987/ads/2015.2.42-57
Aims. To define if the new portable appliances, like smartphone, iPad, small laptop and tablet can be used in cephalometric tracing without dropping out the validity of any measurement.
Methods. We investigated and compared the reproducibility and the speed of landmarks identification process on lateral X-rays in two input devices: a mouse-driven cursor and a pen used as input means in mobile devices. One expert located 22 landmarks on 15 lateral X-rays in a repeated measure design two times, at time T1 and T2, after at least one month. The Intraclass Correlation coefficient was used to evaluate the reproducibility for each landmark tracing and the agreement between the value derived from both input devices. Also, the mean errors in measurements, the standard deviation and the Friedman Test significans (P &lt; 0.05) between both input were statistically evaluated.
Results. All landmarks had a high agreement and the Friedman Test indicated statistically significant differences (P&lt;0.05) for the identification of Na, Po, Pt, PNS, Ba, Pg, Gn, UIE, UIA, APOcc and PPOcc landmarks.
Conclusions. Even if the mouse input give higher agreement for landmark tracing the differences are really minimal and they can be ignored in private practice. We suggest the adequacy of pen input in clinical setting.
application/pdf
1971-1441
91
2
en
R. Leonardi 
https://creativecommons.org/licenses/by-nc-nd/4.0
Annali di stomatologia
intraexaminer reliability
Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor versus pen
Text.Serial.Journal
https://www.annalidistomatologia.eu/ads
6
Original Article
2022-08-12
2022-08-12
2015-06-01
2023-12-04
42-57
Ann Stomatol (Roma)
R. Leonardi 
2015
10.59987/ads/2015.2.42-57
42
1971-1441
2
intraexaminer reliability
en
57
Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor versus pen
https://www.annalidistomatologia.eu/ads/article/download/91/77
6
                                                                                                    Original article



    Reproducibility and speed of landmarking process
    in cephalometric analysis using two input devices:
    mouse-driven cursor versus pen




                                                                                                      i
                                                                                                    al
                                                                                                 on
    Alice Cutrera, DDS1                                         are really minimal and they can be ignored in pri-
    Ersilia Barbato, DMD, MSD2                                  vate practice. We suggest the adequacy of pen in-
    Francesco Maiorana, PhD3                                    put in clinical setting.
    Daniela Giordano, MS, PhD3
    Rosalia Leonardi, DMD, MSD4                                 Key words: computed aided cephalometric land-




                                                                                         zi
                                                                mark tracing, landmark identification errors, later-
                                                                al cephalometry, intraexaminer reliability.
    1   Department of Orthodontics, University of Catania,




                                                                            na
        Italy
    2   Department of Oral and Maxillofacial Sciences, School   Introduction
        of Dentistry, “Sapienza” University of Rome, Italy
    3   Department of Electrical, Electronic and Computer       Cephalometric analysis is one of the major diagnostic
                                                                tool in orthodontic, since 1931 when Broadbent intro-




                                                                  er
        Engineering, University of Catania, Italy
    4   Department of Medical and Surgical Science, Sec-        duced a standard diagnostic method to analyze the
        tion of Dentistry, University of Catania, Italy         lateral head film (1). The constant progress in tech-
                                                                nologies has allowed the orthodontists to perform the



                                                          t     cephalometric analysis on digital head film by means
    Corresponding author:
    Alice Cutrera
                                                       In       of computer software simplifying the landmark identi-
                                                                fication process, because of the image enhancement
    Department of Orthodontics, University of Catania           (2-5), and eliminating the majority of the errors that
    Via S. Sofia, 78                                            usually occurs during the hand tracing (drawing lines
    97019 Vittoria (Catania), Italy                             and use rulers and protractors for measuring dis-
                                                 ni
    E-mail: alice.cutrera@gmail.com                             tances and angles) (6, 7). Additionally, the cephalo-
                                                                metric analysis performed on digital images lets the
                                                                decreasing of time spent during the private practice
                                    io

    Summary                                                     and lets to achieve many different analysis at one
                                                                time (8).
    Aims. To define if the new portable appliances,             However, landmark identification on lateral X-ray still
    like smartphone, iPad, small laptop and tablet can          is the main source of error in cephalometric analysis
                           iz



    be used in cephalometric tracing without drop-              regardless of the kind of input devices used. Abelson
    ping out the validity of any measurement.                   compared the reliability of cephalometric landmark-
    Methods. We investigated and compared the re-               ing using both mouse and pen input focusing on mi-
           Ed




    producibility and the speed of landmarks identifi-          cro parameters differences (9, 10-18). The Author
    cation process on lateral X-rays in two input de-           claimed that the landmarking process and cephalo-
    vices: a mouse-driven cursor and a pen used as              metric tracing soft tissue and hard tissue outlines is
    input means in mobile devices. One expert locat-            faster and more accurate using a pen tablet than a
    ed 22 landmarks on 15 lateral X-rays in a repeated          mouse. Vogel (19) evaluated the hand occlusion with
    measure design two times, at time T1 and T2, af-            tablet sized direct pen input. But, only few Authors
IC




    ter at least one month. The Intraclass Correlation          studied how new technological devices with their
    coefficient was used to evaluate the reproducibili-         small monitors size (iPad, smartphone, tablets) could
    ty for each landmark tracing and the agreement              affect the efficiency of the accuracy of cephalometric
    between the value derived from both input de-               tracing process in orthodontics. Goracci and Ferrari
C




    vices. Also, the mean errors in measurements,               (20) analyzed the reproducibility of cephalometric
    the standard deviation and the Friedman Test sig-           measurements performed with software for tablet
    nificans (P < 0.05) between both input were statis-         (where the clinician had to identify the landmarks
    tically evaluated.                                          with a stylus pen on the tablet screen) and for per-
                                                                sonal computers. Those Authors concluded that Pc-
©




    Results. All landmarks had a high agreement and
    the Friedman Test indicated statistically signifi-          aided and tablet-assisted cephalometric tracing had
    cant differences (P<0.05) for the identification of         good agreement, but they did not evaluate if the
    Na, Po, Pt, PNS, Ba, Pg, Gn, UIE, UIA, APOcc and            landmarks are more affected to errors during their
    PPOcc landmarks.                                            detection in both devices. However, in that study, the
    Conclusions. Even if the mouse input give higher            speed efficiency for both digital appliances was not
    agreement for landmark tracing the differences              analyzed.

    Annali di Stomatologia 2015; VI (2): 47-52                                                                      47
    A. Cutrera et al.


    The aim of this study, therefore, is to compare two            the quality levels found in daily clinical practice. A
    classical input devices, mouse and pen, by consider-           sample collection was approved by the Local Re-
    ing macro results and performance on a real clinical           search Ethics Committee and informed consent was
    task such as a complete cephalometric landmarking              obtained from each patient’s parents before the
    analysis requiring great precision in pointing. Hence,         study. The cephalometric radiographs were scanned




                                                                                                              i
    we wanted to understand if the two different input de-         (Epson Expression 1680 Twain 2.10 Pro, Epson




                                                                                                            al
    vices affect:                                                  Company) at a resolution of 300 dpi with 256 gray
    1. accuracy of landmarks detection in lateral                  levels to transform the analogue image into tiff digital
        cephalometric X-ray;                                       format and stored blinded in a Personal Computer




                                                                                                         on
    2. to quantify time spent to detect the landmarks.             (Intel Pentium IV, 3.2 GH with 2 GB RAM, 300 GB
                                                                   Hard Disk, ASUSTeK Computer Incorporated). An ex-
                                                                   tension of a software developed in other analysis (14)
    Materials and methods                                          was used to record landmark coordinates and their
                                                                   Euclidean distances in millimeters. Twenty-two com-




                                                                                               zi
    All the cephalometric landmarks in both devices were           monly used cephalometric landmarks were included
    recordered by the same investigator, just graduated            in this study (10) (Tab. 1). The sequence of land-
    from the Department of Orthodontic at the University           marks was enforced by the software interface. The




                                                                                na
    of Catania, performed complete cephalometric analy-            software tool also logged the time elapsing between
    sis on 15 X-rays, randomly collected from the                  any two consecutive landmarks, the total time spent
    archives of the Orthodontics Department from 2010              recording the landmarks and the whole set up of
    till 2014. To simulate common clinical practice, we            mouse movements.




                                                                     er
    didn’t deliberately focus on gender, type of occlusion         The observer recorded the 22 landmarks on the im-
    and skeletal patterns. The subjects (5 males and 10            ages displayed on a Toshiba Portege M205 with a
    females) were aged between 10 and 15 (mean age                 1200 TFT polysilicon display with a native 1400 X
    12.9 ± 1.7). Exclusion criteria were: (1) unerupted or         1050 resolution (Toshiba America Inc., New York,
    missing incisors or (2) unerupted teeth overlying the


                                                          t        USA). The equipment was used in tablet mode with
                                                       In
    incisor apices; (3) obvious malpositioning of the head
    in the cephalostat; (4) no unerupted or partially erupt-
                                                                   the pen parallel to the desk and in laptop mode when
                                                                   the mouse was used as landmarking device. The
    ed teeth that would have hindered landmark identifi-           scanned images maximum size was 2700 X 2500 pix-
    cation; (5) patients with severe cranio-facial deformi-        els and they were resized keeping the original propor-
    ties; (6) posterior teeth not in maximum intercuspa-           tions by a resampling procedure available in Adobe
                                          ni
    tion and (7) facial asymmetries. Image quality was             Photoshop CS4 software (Adobe, Inc. San Jose, Cali-
    not used as an exclusion criteria since the selection          fornia, USA) in order to obtain images with a vertical
    was made from a pool of images representative of               side of 900 pixels maximum in order to display all the
                                 io


    Table 1. The twenty-two commonly used cephalometric landmarks included in this study.

                                 Landmarks
                           iz



    Name                         Abbreviation   Definition
    Nasion                       Na             Junction of the frontal nasal bones at the naso-frontal suture
          Ed




    Sella                        S              The midpoint od Sella Turcica
    Orbitale                     Or             The most inferior point of the infraorbital margin
    Porion                       Po             The most superior point of infraorbital margin
    Basion                       Ba             The lowest point on the anterior margin of the foramen magnum in the midline
    Pterigo- Maxillary Fessure   Pt             The intersection of the posterior border of the foramen rotundum
                                                 with the posterior wall of the pterigomaxillary fessure
    Anterior Nasal Spine         ANS            Tip of the Anterior Nasal Spine
IC




    Point A                      A              The deepest point in the concavity of the anterior maxilla between the anterior
                                                 nasal spine and the alveolar crest
    Posterior Nasal Spine        PNS            Tip of the Posterior Nasal Spine
    Point B                      B              The deepest in the concavity of the anterior mandible between the alveolar
C




                                                 crest and Pogonion
    Menton                       Me             The most inferior point of the Chin
    Gonion                       Go             The most outward point on the angle of the mandible formed
                                                 by the conjunction of the rams and the body of the mandible
    Condilion                    Co             The most upper-posterior point of the condile
©




    Upper Incisal Edge           UIE            Tip of the crown of the upper central incisor
    Lower Incisal Edge           LIE            Tip of the lower central incisor
    Upper Incisal Apex           UIA            Tip if the apex of the upper central incisor
    Lower Incisal Apex           LIA            Tip of the apex of the lower central incisor
    Anterior Occlusal Plane      APOcc          Contact point between the first upper and lower premolars
    Posterior Occlusal Plane     PPOcc          Contact point between the first upper and lower molars


    48                                                                                  Annali di Stomatologia 2015; VI (2): 47-52
    Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor
    versus pen

    X-ray without scrolling bars. The participant didn’t            After outliers removal the mean and standard devia-
    have any previous experience with software tool and             tions of the distances between the landmark coordi-
    he was briefed about the purpose of the experiment.             nates at T1 and T2 for each landmark, and the time
    The landmarking process was performed directly on               spent to locate each landmark were computed for
    the monitor displayed X-ray with a mouse-controlled             each of the two experimental conditions.




                                                                                                          i
    cursor. This cursor consisted of an empty arrow. A red          For each input devices were calculated the mean er-




                                                                                                        al
    dot on the selected pixel was used to signal the se-            rors and the standard deviations (in millimeters) of
    lected landmark on the screen. The landmark position            the Euclidean distance in landmark pointing between
    could be corrected until the operator was satisfied.            T1 and T2. It was also detected the Friedman’s test




                                                                                                     on
    A repeated measure design was chosen. The first                 significance between T1 and T2 for mouse cursor
    time (T1), the observer performed the identification of         and pen input device where the significance level was
    22 landmarks on all the 15 X-rays, without any time             5% (P<0.05). Non-parametric Friedman’s test was
    limit, on each of the two input devices. A rotation             used to analyze the variance in a repeated measures
    scheme was used to ensure that any X-ray head film              design because the data sets had a non-normal dis-




                                                                                             zi
    was displayed to the examiner at the same frequency             tribution with non homogeneous variance. All statisti-
    on each one of the two input devices, in order to               cal analysis were done with the software MATLAB
    avoid any learning effect. No more than 5 radi-                 version 7.10.0.499 (R2010a) (The Mathworks, Natik,




                                                                                na
    ographs per day were analyzed to avoid the examiner             MA, USA) and its Statistics toolbox.
    fatigue (21). The landmarking process was repeated
    a second time (T2) for all X-rays and in both advices
    at least one month after the first session. Overall in          Results




                                                                      er
    the experiment 3,960 data points from the investiga-
    tor, two input devices, 15 radiographs, 22 landmarks            Table 2 shows the ICC values of landmarking
    and 2 repeated measures were collected. The Euclid-             process with the mouse-cursor devices for both times
    ean distance between each cephalometric point lo-               (T1 and T2) and Table 3 shows the ICC of landmark-
    cated at T1 and T2 for both devices was used as the


                                                             t      ing process between T1 and T2 using the pen device.
    gold standard measurement to assess repeatability.
                                                          In
    The Intraclass Correlation Coefficient was calculated for
                                                                    All the pointing processed had ICC >̳ 0.95: this result
                                                                    was indicative of a very high agreement among the
    each Euclidean distance landmark detection to define            landmarking process for both devices. The mouse-
    the reliability of the point identification for each used in-   cursor device had the highest values of correlation,
    put device. The ICC was computed using the more re-             ICC > 0.996, for Menton (X-axis), Orbitale (X-axis)
                                                 ni
    strictive index of absolute agreement on the basis of the       and Basion (X-axis). The pen device had the highest
    vector distance of the landmark position from the origin        values of correlation, ICC > 0.996 for Sella (X-axis),
    of the coordinates system (10). Overall the rate of             Porion (X-axis) and Pterigo-maxillary fissure (X-axis).
                                    io

    agreement was considered low for an ICC <         ̳ 0.80 and    After outliers removal the mean and standard devia-
    an ICC > 0.80 was indicative for good agreement.                tions of the distances between the landmark coordi-
                           iz


    Table 2. The Intra-Class Correlation for the mouse cursor devise evaluates the agreement among the landmarking process
    in T1 and T2. The agreement is high when ICC>0.80.

    Mouse-Cursor Device                                  X-axis                                       Y-axis
          Ed




    Nasion                                               0,997535404229079                            0,99752295715014
    Sella                                                0,999401854224947                            0,987099486029854
    Orbitale                                             0,999666897017603                            0,99005469272275
    Porion                                               0,999569537007793                            0,980427303078359
    Basion                                               0,999156109755965                            0,996381499987584
    Pterigoid maxillary fessure                          0,999697903832193                            0,999454418826513
IC




    Anterior Nasal Spine                                 0,998665572003988                            0,992379285485212
    A Point                                              0,9971841105861                              0,98115227811275
    Posterion Nasal Spine                                0,989655916459857                            0,989261997063066
    B Point                                              0,999502641163362                            0,998076974380408
C




    Pogonion                                             0,994347093257402                            0,983123759705164
    Gnation                                              0,987763576302059                            0,988314973962179
    Menton                                               0,998168211697634                            0,99575280126277
    Gonion                                               0,99611348877175                             0,969128526136086
    Condylion                                            0,992494024483712                            0,995058661875066
©




    Occlusal Point Upper Incisor                         0,988628251924127                            0,998653318730979
    Occlusal Point Lower Incisor                         0,952687899194511                            0,986275922263936
    Apex Upper Incisor                                   0,953401022916771                            0,991830699536617
    Apex Lower Incisor                                   0,99625081352735                             0,983498206000574
    Anterior Occlusal Point                              0,993671053793834                            0,955790067372581
    Posterior Occusal Point                              0,997407175137818                            0,988157332078623


    Annali di Stomatologia 2015; VI (2): 47-52                                                                           49
    A. Cutrera et al.


    Table 3. The Intra-Class Correlation for the pen devise evaluates the agreement among the landmarking process in T1 and
    T2. The agreement is high when ICC > 0.80.

    Pen device                                          X-axis                                          Y-axis
    Nasion                                              0,997535404229079                               0,99752295715014




                                                                                                            i
    Sella                                               0,999401854224947                               0,987099486029854




                                                                                                          al
    Orbitale                                            0,999666897017603                               0,99005469272275
    Porion                                              0,999569537007793                               0,980427303078359
    Basion                                              0,999156109755965                               0,996381499987584




                                                                                                       on
    Pterigoid maxillary fessure                         0,999697903832193                               0,999454418826513
    Anterior Nasal Spine                                0,998665572003988                               0,992379285485212
    A Point                                             0,9971841105861                                 0,98115227811275
    Posterion Nasal Spine                               0,989655916459857                               0,989261997063066
    B Point                                             0,999502641163362                               0,998076974380408




                                                                                             zi
    Pogonion                                            0,994347093257402                               0,983123759705164
    Gnation                                             0,987763576302059                               0,988314973962179
    Menton                                              0,998168211697634                               0,99575280126277




                                                                               na
    Gonion                                              0,99611348877175                                0,969128526136086
    Condylion                                           0,992494024483712                               0,995058661875066
    Occlusal Point Upper Incisor                        0,988628251924127                               0,998653318730979
    Occlusal Point Lower Incisor                        0,952687899194511                               0,986275922263936
    Apex Upper Incisor                                  0,953401022916771                               0,991830699536617




                                                                    er
    Apex Lower Incisor                                  0,99625081352735                                0,983498206000574
    Anterior Occlusal Point                             0,993671053793834                               0,955790067372581
    Posterior Occusal Point                             0,997407175137818                               0,988157332078623




                                                          t
                                                       In
    Table 4.The mean error, the standard deviation and the Friedman’s test significance between T1 and T2 in millimeters for
    the cephalometric landmarks detected with the two input devices: mouse and pen. NS = not significant. P < 0.05.

    Landmark                          Mouse                              Pen                                     Significance
    Na                                0,37±0,21                          0,57±0,31                               *
                                          ni
    S                                 0,30±0,10                          0,38±0,19                               NS
    Or                                0,91±0,58                          0,91±0,48                               NS
    Po                                0,68±0,21                          0,72±0,35                               NS
                                   io

    Ba                                0,59±0,28                          1,34±0,90                               *
    Pt                                0,92±0,54                          1,63±1,00                               *
    ANS                               0,76±0,42                          0,76±0,42                               NS
    A                                 0,44±0,18                          0,65±0,26                               *
                        iz



    PNS                               0,79±0,42                          0,99±0,57                               NS
    Ba                                0,81±0,40                          0,73±0,40                               NS
    PM                                0,57±0,25                          0,66±0,40                               NS
          Ed




    Pg                                0,39±0,21                          0,54±0,31                               *
    Gn                                0,54±0,24                          0,80±0,42                               NS
    Me                                0,37±0,21                          0,72±0,26                               *
    Go                                1,10±0,65                          1,48±0,43                               NS
    Co                                1,22±0,63                          1,56±0,91                               NS
    UIE                               0,27±0,12                          0,29±0,18                               NS
IC




    LIE                               0,32±0,17                          0,37±0,16                               NS
    UIA                               0,98±0,45                          0,95±0,34                               NS
    LIA                               0,97±0,41                          1,24±0,52                               NS
    APOcc                             0,84±0,24                          1,63±1,00                               NS
    PPOcc                             0,97±0,37                          1,58±0,63                               *
C




    nates at T1 and T2 for each landmark, and the time            tically significant difference, with P < 0.05, in land-
    spent to locate each landmark, were computed for              mark detection repeatability under the two experi-
©




    the two experimental conditions.                              mental conditions. In all the cases with statistically
    The mean errors and the standard deviations (in mil-          significant difference the lowest error was obtained
    limeters) of the Euclidean distance in landmark detec-        with the mouse as input device.
    tion between T1 and T2 and the significance of the            Table 5 shows the mean values, standard deviations
    Friedman’s test are reported in Table 4 for each input        and the significance of the Friedman’s test of the time
    device. The Friedman test indicates that, except for          employed by the observer to locate each cephalomet-
    Na, Ba, Pt, A, Pg, Me and PPocc there was no statis-          ric landmark (averaged over all users and images

    50                                                                                Annali di Stomatologia 2015; VI (2): 47-52
    Reproducibility and speed of landmarking process in cephalometric analysis using two input devices: mouse-driven cursor
    versus pen

    Table 5. The mean, standard deviation and Friedman’s test significance for the time, in hundreds of seconds, required to
    digitize each landmark. Data have been averaged over all users, all X-rays at T1 and T2 for each of the two input devices:
    mouse and pen. NS = not significant. p < 0.05.

    Landmark                            Mouse                              Pen                                  Significance




                                                                                                            i
    Na                                  439,29±253,51                      718,94±652,18                        *




                                                                                                          al
    S                                   252,25±92,88                       298,74±91,28                         NS
    Or                                  164,72±48,81                       222,61±26,37                         NS
    Po                                  166,94±73,64                       214,42±65,45                         *




                                                                                                       on
    Ba                                  257,50±97,64                       286,44±95,92                         NS
    Pt                                  148,04±67,66                       202,52±71,82                         *
    ANS                                 256,03±84,73                       300,62±68,93                         NS
    A                                   265,88±124,29                      225,54±139,94                        NS
    PNS                                 248,25±121,93                      312,24±132,17                        *




                                                                                              zi
    Ba                                  158,39±64,60                       278,90±52,46                         *
    PM                                  338,63±115,25                      359,37±209,16                        NS
    Pg                                  216,21±109,94                      398,53±152,87                        *




                                                                                 na
    Gn                                  192,96±86,22                       288,58±135,58                        *
    Me                                  204,41±107,19                      223,60±117,58                        NS
    Go                                  346,25±106,06                      465,50±220,38                        NS
    Co                                  203,58±79,22                       264,84±34,85                         NS
    UIE                                 98,73±71,75                        170,77±90,20                         *




                                                                     er
    LIE                                 247,46±77,80                       228,44±94,90                         NS
    UIA                                 106,58±48,84                       227,19±108,98                        *
    LIA                                 271,24±104,59                      277,52±98,89                         NS
    APOcc                               146,45±63,95                       250,65±33,13                         *
    PPOcc                               368,68±130,36


                                                           t               489,57±156,23                        *
                                                        In
    during both experiments i.e. T1 and T2), for the two           bitale, and Lower Incisor Apex are unreliable because of
    input devices. Statistically significant differences           the superimposition of many anatomic structures that
    (P<0.05) were found for landmarks Na, Po, Pt, PNS,             causes great variation. This difference could be be-
                                                 ni
    Ba, Pg, Gn, UIE, UIA, APOcc and PPOcc.                         cause the digital images can be manipulated to improve
                                                                   the quality of the lateral head films so to reduce errors
                                                                   due to the superimposition of other anatomical struc-
                                    io

    Discussion                                                     tures or to the low contrast of the X-ray (4, 5, 7).
                                                                   About the time spent to point the landmarks on lateral
    The development of technology introduced the ortho-            X-rays, even if a statistically significant difference ex-
    dontists to a new approach for diagnosis by the use            ist for half of the landmarks, the difference of the sum
                           iz



    of digital systems for tracing and analyzing cephalo-          of average time spent is 51 seconds when the mouse
    metric head films. Digital radiology has many advan-           is used as input device and 67 seconds when the pen
    tages: reduced radiation dose, easier information ac-          is used as input device. This difference is reduced if
          Ed




    cess and image manipulation (22, 23), however the              we avoid considering the first landmark that usually
    reproducibility of digital cephalometric analysis has to       requires more time to be located due to the habit of
    be high and has to reduce to the minimum the errors.           the expert to obtain an overall impression of the
    To avoid the inter examiner errors and to standardize          X-ray. In this case the time required using the mouse
    the protocol for a comparative study, all the tracings         is 47 seconds and the time required using the pen is
    were done by the same investigator.                            60 seconds. In any case a difference between 16 and
IC




    Based on the Friedman test outcomes, there is no               13 seconds for an entire analysis is not so relevant in
    statistically significant difference on the repeatability      clinical practice.
    of landmark detection for the two input device, except         The difference in landmarking using the pen can be
    for Nasion, Basion, Pterigo-Maxillary Fessure, A               due to the parallax error experienced and reported by
C




    Point, Pogonion, Menton and Posterio Occlusal                  the expert in a post interview and in a questionnaire
    Plane. For all those landmarks with statistically differ-      that requires an inspection to precisely locate the
    ence, the lowest error was obtained using the mouse.           landmarks. However, the characteristic method of
    This can be due to the parallax error using the pen. In        landmark detection by touching the screen needed to
©




    some cases locating some landmarks, such as Me,                be tested in an independent study.
    requires to move the hand down to avoid hand occlu-            In conclusion this work is a quantitative study to eval-
    sions of the area where the landmark lies.                     uate the differences between two different input de-
    Our findings are not in line with Chen, Polat-Ozsoy and        vices, mouse and pen, in accuracy and speed land-
    Celik’s results (22-24), who analyzed the reproducibility      marking process. Hence we claim:
    of the landmarking process during conventional hand-           • Landmarks, in most of the cases, were pointed with
    tracing. These Authors claimed that Gonion, Porion, Or-             more accuracy by mouse device respect the pen;

    Annali di Stomatologia 2015; VI (2): 47-52                                                                             51
    A. Cutrera et al.


    •  Less time was needed to identify the landmarks                    11. Giordano D, Leonardi R. Web-trace and the learning of vi-
       with the mouse device.                                                sual discrimination skills. 1st International Workshop on Pen-
    The difference in accuracy with the advent of more                       Based Learning Technologies. PLT. 2007.
                                                                         12. Leonardi R, Giordano D, Caltabiano M. Interactive online pro-
    sophisticated devices will probably decrease and it
                                                                             gram to improve cephalometric tracing skills. Am J Orthod
    could be interesting to extend the analysis to new pen




                                                                                                                       i
                                                                             Dentofacial Orthop. 2004;126;256-258.
    devices as well as to evaluate the performance when




                                                                                                                     al
                                                                         13. Abelson M. Potpourri II. Digital Imaging Update. Am J Or-
    touch input is used.                                                     thod Dentofacial Orthop. 1999;115;599-601.
                                                                         14. ISO, Ergonomic requirements for office work with visual dis-
                                                                             play terminals (VDTs), Part 9: Requirements for non-keyboard




                                                                                                                  on
    References                                                               input devices. International Organization for Standardisation.
                                                                             2000.
     1. Liu JK, Cheng KS. Accuracy of computerized automatic iden-       15. Fitts PM. The information capacity of the human motor sys-
        tification of cephalometric landmarks. Am J Orthod Dento-            tem in controlling the amplitude of movement. J Exp Psy-
        facial Orthop. 2000;118:535-540.                                     chology. 1954;47;381-391.




                                                                                                       zi
     2. Major PW, Johnson DE, Hesse KL, Glover KE. Landmark              16. MacKenzie IS, Sellen A, Buxton W. A comparison of input
        identification error in posterior anterior cephalometrics. An-       devices in elemental pointing and dragging tasks. Proc CHI,
        gle Orthod. 1994;64:447-54.                                          New York: ACM.1991;161-166.




                                                                                        na
     3. Sicurezza E, Greco M, Giordano D, Maiorana F, Leonardi           17. Accot J, Zhai S. Beyond Fitts’ law: models for trajectory-based
        R. Accuracy of landmark identification on postero-anterior           HCI tasks. In Proceedings of the ACM SIGCHI Conference
        cephalograms. Prog Orthod. 2012;13;132-140.                          on Human factors in computing systems. ACM. 1997;295-
     4. Leonardi RM, Giordano D, Maiorana F, Greco M. Accura-                302.
        cy of cephalometric landmarks on monitor-displayed radi-         19. MacKenzie IS, Kauppinen T, Silfverberg M. Accuracy mea-
        ographs with and without image emboss enhancement. Eur               sures for evaluating computer pointing devices. In Pro-




                                                                           er
        J Orthod. 2010;32;242-247.                                           ceedings of the SIGCHI conference on Human factors in com-
     5. Giordano D, Maiorana F, Leonardi R. Effects of monitor size          puting. New York, ACM. Systems. 200;9-16.
        on accuracy and time needed to detect cephalometric radi-        20. Vogel D, Cudmore M, Casiez G, Balakrishnan R, Keliher L.
        ographs landmarks. Displays. 2012;33;206-213.                        Hand occlusion with tablet-sized direct pen input. In Pro-
     6. Tsorovas G, Karsten AL. A comparison of hand-tracing and


                                                                  t          ceedings of the SIGCHI Conference on Human Factors in
        cephalometric analysis computer programs with and with-
        out advanced features-accuracy and time demands. Eur J
                                                               In            Computing Systems. ACM. 2009;557-566.
                                                                         21. Goracci C, Ferrari M. Reproducibility of measurements in
        Orthod. 2010;32:721-728.                                             tablet-assisted, PC-aided, and manual cephalometric analy-
     7. Leonardi R, Giordano D, Maiorana F. An evaluation of cel-            sis. Angle Orthod. 2014;84;437-442.
        lular neural networks for the automatic identification of        21. Erkan M, Gurel HG, Nur M, Demirel B. Reliability of four dif-
                                                ni
        cephalometric landmarks on digital images. J. Biomed.                ferent computerized cephalometric analysis programs. Eur
        Biotechnol. 2009;1-12. Article ID 717102.                            J Orthod. 2012;34:318-321.
     8. AlBarakati SF, Kula KS, Ghoneima AA. The reliabiity and the      22. Chen YJ, Chen SK, Chan HF, Chen KC. Comparison of land-
        reproducibility of cephalometric measurements: a compar-             mark identification in traditional versus computer-aided
                                     io

        ison of conventional and digital methods. Dentomaxillofac            digital cephalometry. Angle Orthod. 2000;70:387-392.
        Radiol. 2012;41:11-17.                                           23. Celia E, Polat-Ozsoy O, Ufuk Toygar Memikoglu T. Com-
     9. Trpkova B, Major P, Prasad N, Nebbe B. Cephalometric land-           parison of cephalometric measurements with digital versus
                           iz


        marks identification and reproducibility: a meta analysis. Am        conventional cephalometric analysis. Eur J Orthod.
        J Orthod Dentofacial Orthop. 1997;112:165-70.                        2009;31:241-246.
    10. McClure SR, Sadowsky PL, Ferreira A, Jacobson A. Relia-          24. Polat-Ozsoy O, Celik E, Ufuk Toygar Memikoglu T. Differ-
        bility of digital versus conventional cephalometric radiology:       ences in cephalometric measurements: a comparison of dig-
          Ed




        a comparative evaluation of landmark identification error. In        ital versus hand-tracing methods. Eur J Orthod. 2009;31:254-
        Seminars in Orthodontics. 2005;11:98-110. WB Saunders.               259.
IC
C
©




    52                                                                                          Annali di Stomatologia 2015; VI (2): 47-52
