Clin Plastic Surg 31 (2004) 141–148

Three-dimensional technology for documentation and

record keeping for patients with facial clefts

Adriana C. Da Silveira, DDS, MS, PhDa,b,*, Orlando Martinez, DDSa,Dimitrio Da Silveira, MSc, Joseph L. Daw Jr, DDS, MDa,d,e,

Mimis Cohen, MDd,e,f

aThe Craniofacial Center, The University of Illinois at Chicago, 811 South Paulina Street (MC 588), Chicago,

IL 60612, USAbDepartment of Orthodontics, The University of Illinois at Chicago, 801 South Paulina Street (MC 841), Chicago,

IL 60612, USAcStatistical Consultant, Chicago, IL, USA

dDepartment of Surgery, The University of Illinois at Chicago, 840 South Wood Street (MC 958), Chicago, IL 60612, USAeDivision of Plastic Surgery, The Craniofacial Center, The University of Illinois at Chicago, 820 South Wood Street (MC 958),

Chicago, IL 60612, USAfCook County Hospital, 1901 West Harrison Street, Chicago, IL 60612, USA

Records are essential to any investigative process Pruzansky and Lis in 1958 [5] with a description of

because they are prerequisites for adequate diagnosis.

Moreover, they are important for treatment planning

and are fundamental for the correct evaluation of

treatment progress [1]. This is especially important in

the treatment of cleft lip and palate and craniofacial

anomalies because there are several treatment proto-

cols available, and outcomes vary greatly between

cases. The essential elements of good record gath-

ering in craniofacial research and clinical practice

are medical and dental examinations, photographs,

impressions, and radiographs [1–4]. Although radio-

graphs are an essential source of information and

were routinely taken on infant patients in the past,

this is not the case anymore due to the possible harm-

ful effects of x-rays. When such examination is

required, CT scans are the examination of choice be-

cause they provide three-dimensional (3-D) informa-

tion in high resolution.

The guidelines of record keeping for treatment of

cleft lip and palate patients were first reported by

0094-1298/04/$ – see front matter D 2004 Elsevier Inc. All right

doi:10.1016/S0094-1298(03)00139-1

* Corresponding author. The Craniofacial Center, The

University of Illinois at Chicago, 811 South Paulina Street

(MC 588), Chicago, Illinois 60612.

E-mail address: ads@uic.edu (A.C. Da Silveira).

a protocol for record acquisition, and its importance

was reinforced by Mazaheri and Sahni in 1969 [1]. At

that time, children over 2 months of age were referred

for radiographic examination under sedation. Intra-

oral and facial impressions were taken while the in-

fant was awake so that the infant would maintain his

own reflexes. Impressions were critical procedures

that required at least four assistants and a fair amount

of patience [1].

New imaging techniques have been developed

since then, and data collection is easier and more

qualified. On the other hand, impression techniques

have not improved in the same amount as imaging. It

is still difficult to get an infant’s cooperation, and soft

tissue deformation is likely to occur due to tension

and weight of the impression material [6]. Impression

techniques have been developed in an attempt to

minimize such distortions [7–10]. Furthermore, this

distortion can be increased as the impressions get

filled with plaster and stone for fabrication of casts

and models.

Different methods for facial impressions of infants

with clefts have been described, including cumber-

some methods that require the participation of many

team members and extensive manual skill and prac-

tice [11,12]. Our experience is that it is possible to

s reserved.

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148142

take intraoral impressions with the infant awake with

the help of only one assistant, usually one of the

parents. The assistant holds the infant dorsally laid on

his legs, and the operator uses a small manually

constructed tray filled with irreversible hydrocolloid

(Lascod; Siesto Fiorentino, Firenze, Italy) or green

compound (Kerr, Orange, CA) [13]. Facial impres-

sions are taken only in the operating room before the

surgery, when the child is already sedated to receive

the major procedure. These impressions provide 3-D

information in addition to 2-D information from pho-

tographs, which have been demonstrated not to be

precise [14,15]. It has been said that ‘‘photographs

are only as good as the photographer’’ [15]. There is

an elemental problem in representing 3-D structure in

a 2-D form. 2-D analysis provides incomplete data

and does not account for differences in facial depth

and shape.

The problems and limitations associated with casts

and models from intraoral and facial impressions

include the production, storage, and archiving costs

of plaster models, including space for storage, espe-

cially considering that craniofacial and cleft patients

may be in treatment from birth until early adult-

hood. Accessibility and availability to such records

for evaluation of treatment progress and outcome,

treatment plan, research, and communication be-

tween professionals that are not located in the same

site may be difficult.

A variety of 3-D acquisition techniques for soft

tissue have been developed in recent years that can be

Fig. 1. Example of a 3-D image (A) and mesh d

applied to imaging of the human body. Several

commercially available devices have been developed

that are based on any one of a wide variety of tri-

angulation-based 3-D sensing techniques (eg, laser

baselines, camera-projector baselines, and camera-

camera baselines). Stereophotogrammetry provides

an alternative to overcome the limitations of facial

impressions and 2-D photographs [16,17]. Another

promising choice is 3-D noncontact laser surface

scanning [18–21], which has been used for visual-

ization of craniofacial surgery and its effects [22–28].

Its advantages include noninvasiveness and noncon-

tact with the patient. The reliability of a noncontact

surface laser scanner (Vivid700; Minolta, Ramsey,

NJ) was assessed when manually derived measure-

ments on a plaster facial model were compared with a

computerized technique [21]. The two measurements

did not differ statistically; therefore, the second

methodology could be considered consistent.

The objectives of the present study were to assess

the suitability and the reliability of the noncontact

3-D laser surface scanner for documentation and

record keeping of infants with facial clefts.

Materials and methods

Method for 3-D image acquisition

The Vivid700 operates on a light-stripe triangula-

tion range-finder principle. The subject’s facial sur-

iagram (B) of an infant born with UCLP.

Table 1

Demographics of the sample

Subject Sex Race Type of cleft

Age at time

of lip repair

(months)

Date of

3-D imaging

Date of

facial impression

Time lapse between

3-D imaging and facial

impression (days)

1 F Hispanic BCLP 6 9/10/02 10/09/02 30

2 F Hispanic BCLP 13 8/27/02 10/16/02 40

3 M African American UCLP 3 2/20/02 3/27/02 37

4 M Asian UCLP 4 9/10/02 9/20/02 10

5 M Caucasian UCLP 3 2/11/03 2/14/03 3

6 M African American UCLP 4 2/19/02 3/01/02 12

7 M Caucasian UCLP 2.5 12/17/02 12/20/02 3

8 F Hispanic UCLP 5 12/10/02 12/20/02 10

9 M Hispanic UCLP 3.5 1/29/02 2/17/03 18

10 F Caucasian/Hispanic UCLP 3 4/28/03 5/13/03 15

11 F Hispanic UCLP 3 1/29/03 2/17/03 20

12 M Asian/Hispanic UCLP 4 5/13/03 6/15/03 32

All subjects had complete clefts. Average length of time lapse between records was 19.16 days.

Abbreviations: UCLP, Unilateral cleft lip and palate; BCLP, bilateral cleft lip and palate.

Table 2

Facial landmarks and their location

Points Facial landmarks

1 Right eye outer canthus

2 Right eye inner canthus

3 Soft tissue nasion

4 Left eye inner canthus

5 Left eye outer canthus

6 Cleft side supra alare

7 Nasal tip

8 Noncleft side supra alare

9 Cleft side alar base

10 Cleft side middle superior alar rim

11 Cleft side columella base

12 Noncleft side columella base

13 Noncleft side middle superior alar rim

14 Noncleft side alar base

15 Cleft side half-distance from alar base

to commissure

16 Cleft side crista philtri

17 Noncleft side crista philtri

18 Noncleft side half-distance from alar

base to commissure

19 Right commissure

20 Cleft side mid distance upper lip

21 Noncleft side mid distance upper lip

22 Left commissure

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148 143

face is scanned from top to bottom with a projected

class 2 laser light stripe. The reliability of this method

has been tested and found to be accurate [21,29,30],

and this methodology has been described [31]. At

The Craniofacial Center, 3-D images are routinely

captured for initial evaluation and subsequent visits.

Infants are placed in the sitting position on the

parent’s lap. A flat background is placed between

the infant and the parent. The laser surface scanner is

positioned at 1 m distant to the subject, and each

scanning takes approximately 1 second. One facial

scanning may contain 40,000 points. A polygonal

mesh is formed of all these points representing the

facial surface (Fig. 1). Cartesian coordinates (x, y,

and z) from facial landmarks [23,32] can be identified

with the surface distance between them calculated

using computer software (Measure; Minolta).

Sample and facial landmarks

The laser surface scanner was used to generate

3-D images of 12 subjects with complete bilateral

cleft lip and palate (BCLP) (n = 2) or complete uni-

lateral cleft lip and palate (UCLP) (n = 10) (Table 1).

Traditionally in our institution, these subjects have

irreversible hydrocolloid (alginate) impressions taken

of their faces while they are under general anesthesia

at the time of lip repair. The plaster casts generated

were also scanned by the same equipment. The

average length of time between the records used in

this study was 19.16 days (Table 1). Although there

were more 3-D images available for each subject,

the ones chosen demonstrated higher quality and de-

tail, which facilitated landmark positioning. All pro-

cedures followed the guidelines of The Office of

Protection of Research Subjects, University of Illinois

at Chicago, and IRB protocol was approved before

initiation of the study. Facial landmarks were iden-

tified by a single operator on the computer screen

(Table 2).

Fig. 2. Location of the facial landmarks on the facial casts of UCLP (A) and BCLP (B) infants. Casts were made from facial

impressions performed at the time of lip repair.

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148144

The intra-examiner reliability was assessed by

collecting a subsample of three subjects (each includ-

ing facial casts and 3-D images directly taken from

the subjects) and repeating the landmark identifica-

tion three times consecutively by the same examiner.

A student’s paired sample t-test was performed for

these twenty and two measurements to determine

whether significant differences between the mean of

three data sets for each subject existed. No statistical

significance was found (P > 0.05).

Lower facial landmarks (lip and nose areas) for

unilateral clefts were chosen to reflect their position

relative to the cleft, which eliminated the problem of

cleft side (right or left). Cartesian coordinates from

each facial landmark derived from facial impressions

and from the 3-D images taken directly from the in-

fant’s faces were obtained by using computer soft-

ware (Measure) (Figs. 2 and 3). Soft tissue nasion

was used as registration point and was defined as

point 0 for all coordinates (0, 0, 0).

Fig. 3. Location of the facial landmarks on a 3-D image of

an infant with UCLP.

Calculations and statistical analysis

After Cartesian coordinates from each facial land-

mark were obtained, the length (or norm) of a vector

was calculated. This length or norm represents the

3-D distance from point (x, y, z) to the origin (0,0,0)

and can be calculated by:

Length =ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffix2 + y2 + z2

p

Student’s paired sample t test with a = 0.05 was

used to test the hypothesis in which the means of

Table 4

Comparison of the means of the vector norms of each

facial landmark between facial casts and facial images for

all subjects in order to evaluate which facial landmarksa

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148 145

the vector norms from facial casts were equal to

the means of the vector norms of facial images for

each subject against the alternative hypothesis in

which the means were different.

are different

Facial landmark Mean difference Standard deviation

1 4.885778b F5.251938

2 1.231117 F2.012768

4 0.4287606 F1.524027

5 2.410748b F3.355056

6 1.858884b F1.952629

7 2.304338b F1.742788

8 3.807297b F1.824886

9 1.720411 F2.6857

10 1.763785b F2.191443

11 2.528122b F2.065665

12 2.811414b F1.775122

13 3.124654b F2.068437

14 3.324007b F2.369221

15 1.318292b F1.718287

16 1.174642 F1.815771

17 1.759326b F1.698682

18 2.667442b F3.200233

19 2.157878 F0.320025

20 1.6264 F2.887341

21 3.28044b F3.967561

22 3.147343b F3.725347

a Student’s paired sample t-test; n = 10 UCLP for 22

facial landmarks; a = 0.05.b Statistically significant.

Results

The results demonstrated that, when comparing

the means of the vector norms (3-D distances for each

facial landmark) from facial casts to the means of the

vector norms of facial images for each subject,

statistical significant difference was found for seven

UCLP subjects and two BCLP subjects (Table 3).

To evaluate which facial landmarks were different

between facial casts and facial images, a student’s

paired sample t test was performed of the means of

the vector norms of each facial landmark between fa-

cial casts and facial images for all subjects. Statisti-

cally significant differences between casts and images

were found for 15 facial landmarks in UCLP subjects

(P< 0.05) (Table 4) and for 21 out of 22 facial land-

marks in BCLP subjects (P< 0.05) (data not shown).

Student’s paired sample t tests were applied sepa-

rately to determine the coordinate (x, y, z) in which

the difference was located for each facial landmark

found to be statistically significant from the previ-

ous analysis. The means of each facial landmark

in each coordinate from facial casts was compared

with its corresponding coordinate means from facial

images. The results are demonstrated in Table 5 and

Table 3

Comparison of the mean differences of the vector norms

(3-D distances for each facial landmark) from facial casts to

the vector norms of facial images for each subject a

Subject Mean difference Standard deviation

1 UCLP 0.0089883 F2.253944

2 BCLP 4.07811b F3.631246

3 UCLP 4.315687b F2.445196

4 UCLP 2.19987b F3.731547

5 UCLP 2.372091b F2.59321

6 UCLP 1.868761b F1.757508

7 UCLP 4.73136b F2.654955

8 UCLP 1.100289 F2.433142

9 UCLP 0.817846 F2.008052

10 UCLP 2.233988b F1.182573

11 BCLP 2.847548b F2.708773

12 UCLP 2.774338b F2.202901

Abbreviations: UCLP, unilateral cleft lip and palate. BCLP,

bilateral cleft lip and palate.a Student’s paired sample t-test. UCLP: n = 10; BCLP:

n = 2. a = 0.05.b Statistically significant.

Table 5

Comparison of the mean differences of each facial land-

mark in each coordinate (x, y, z) (cast-image) for facial

landmarks found to be statistically significant from the pre-

vious analysisa

Mean difference

Facial landmark x y z

1 *

5 *

6 *

7 *

8 *

10 *

11 *

12 *

13 * *

14 * *

15 *

17 *

18 * *

21 * *

22 *

a Student’s paired sample t-test; a = 0.05.* Statistically significant.

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148146

indicate that most differences were found in the

y and z coordinates.

Discussion

In this study, significant differences were found

between the 3-D positions of facial landmarks of 3-D

images taken directly from subjects with facial clefts

using a 3-D laser surface scanner as compared with

their corresponding facial casts. Statistically signifi-

cant differences were found between the means of

vector norms of facial casts and the means of vector

norms of facial images in 7 out of 10 UCLP subjects.

Although we did not investigate the culprit in this

study, we hypothesize that the differences found were

probably due to soft tissue deformations originating

from the facial impressions and, in the cases where no

differences were found, that the impression technique

was more accurate when performed at the time of lip

repair. Facial impressions are taken in the operatory

room by different professionals at different times.

To substantiate this theory, previous studies have

demonstrated this scanner to be accurate, suggesting

that distortions are likely to derive from facial casts

[21,29,30]. Other studies have used the difference of

linear distances between landmarks as a form of 3-D

analysis [22–24]. However, for comparison between

facial casts and 3-D images for the same subjects, this

methodology is not appropriate. If landmarks have

their position in space modified to a certain degree,

such as when an impression material displaces the

soft tissue, it is possible that the linear distance

between two landmarks remains unaltered.

Careful analysis of the differences in facial land-

mark positioning reveals that the differences for the

outer canthi landmarks were found in the x coordi-

nate. An explanation may be that facial impressions

may get distorted in this area due to the face’s curved

shape and the landmarks’ distance from the center of

the face. On the contrary, inner canthi landmarks

were found not to be statistically different.

Differences in facial landmark positioning in the

lower face (nose and lip areas) were found to be pri-

marily in the y coordinate, followed by the z coordi-

nate (Table 5). Soft tissue deformation is likely to

occur due to tension and weight of the impression

material and would be expected to affect the height

and depth of the impression. The position of each

landmark is then altered in the y and z coordinates to

a higher extent. This may be more evident in areas

with greater amounts of soft tissue, such as the nose

and the noncleft lip segment in UCLP subjects.

Due to limited sample size, the data obtained from

BCLP subjects were limited. Nonetheless, these data

demonstrate differences between facial casts and fa-

cial impressions for each subject. Also, all but one

facial landmarks were found to differ between casts

and images in this group.

Although the benefits of the 3-D laser surface

scanning technique are extensive, there are shortcom-

ings, especially when scanning infants. The greatest

barrier faced by 3-D picturing assessment is the

child’s constant motion. It is a challenge to make kids

stay still when posing for pictures [33]. Frequently,

babies do not remain still long enough to have the

scanning completed, which may create distortions of

the 3-D polygonal mesh, especially in the z coordi-

nate, even though scanning takes less than 1 second. It

is our experience that infants older than 6 months are

more difficult to scan. In addition, changes in facial

expression (eg, crying) may affect recording of facial

morphology. It has been suggested to feed the baby

and leave him with his parents in a darker room until

he is asleep [1]. In this study, multiple 3-D scannings

of subjects were performed on a routine basis, starting

from the first visit. However, some of these images

were of poor quality due to the problems previously

mentioned that resulted in some cases in an increased

time lapse between the records analyzed.

Some advantages of having 3-D images in com-

puter format are decreased demand for storage space

in the case of facial casts and easy accessibility of

stored images. There is less need to have specialized

personnel available in the operating room to perform

the facial impressions. Effective communication and

increased efficiency may be facilitated due to potential

exchange of information via e-mail. Moreover, when

the cost of rented space to house records is considered,

the initial investment required to purchase such equip-

ment might be worthwhile.

When comparing 2-D and 3-D pictures, the first

choice is less expensive but often is the result of a

soft tissue compensation of a skeletal deformity.

Photographic analyses are considered inaccurate re-

sources of anthropometric measurements [34]. In the

3-D picture, every point has a coordinate in the x, y,

and z axes, which gives a ‘‘geometric address’’ for

each facial landmark [32,35]. Previously, for this par-

ticular model of 3-D laser surface scanner (Vivid700),

it was found that more accurate measurements in the

height (x) and width ( y) coordinates and less accurate

measurements in depth (z) were produced [21]. Con-

sequently, Minolta has changed its design to posi-

tion the laser beam from the bottom to the top of the

object being scanned to allow more detail and less dis-

tortion. In this study, differences were found in the

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148 147

z coordinate between facial casts and facial images;

however, these differences seemed to be accompanied

by differences seen also in the y coordinate.

Summary

The surface laser scanner has great potential as a

method for documentation of cleft infant due to its

accuracy, ease of use, and convenience. The images

can be stored in the computer for easy access. As

purchasing costs decrease, its acquisition will be fa-

cilitated, resulting in an increase in its use.

Acknowledgments

We thank Dr. Nanci Oliveira, Dr. Silvana Gon-

zalez, Dr. Budi Kusnoto, Dr. Adriana Uribe, Ms. Terri

Kaisling, and Ms. Susan Villegas for their help in

image acquisition and analysis.

References

[1] Mazaheri M, Sahni PP. Techniques of cephalometry,

photography, and oral impressions for infants. J Pros-

thet Dent 1969;21:315–23.

[2] Aduss H, Pruzansky S. Width of cleft at level of the

tuberosities in complete unilateral cleft lip and palate.

Plast Reconstr Surg 1968;41:113–23.

[3] Rosenstein SW. A new concept in the early orthopedic

treatment of cleft lip and palate. Am J Orthod 1969;55:

765–75.

[4] Chandra R, Sharma RN, Makrandi SK. Permanent

records of cleft lip, nose and palate abnormalities. Br

J Plast Surg 1974;27:139–41.

[5] Pruzansky S, Lis EF. Cephalometric roentgenography

of infants: sedations, instrumentation and research. Am

J Orthod 1958;44:159–86.

[6] Mishima K, Sugahara T, Mori Y, Sakuda M. Applica-

tion of a new method for anthropometric analysis of

the nose. Plast Reconstr Surg 1996;98:637–44.

[7] Ma T, Taylor TD, Johnson M. A boxing technique for

making moulages of facial defects. J Prosthet Dent

1990;63:564–6.

[8] Guerra LR, Finger IM, Echeverri J, Shipman B. Impres-

sion making, sculpting, and coloring of orbital pros-

theses. Adv Ophthalmic Plast Reconstr Surg 1992;9:

287–96.

[9] Mitchell D, Shipman B. Impressions for oculofacial

prosthetics. Adv Ophthalmic Plast Reconstr Surg

1992;9:273–83.

[10] Coleman AJ, Schweiger JW, Urquiola J, Tompkins

KA. A two-stage impression technique for custom

facial prostheses. J Prosthet Dent 1995;73:370–2.

[11] Bacher M, Goz G, Pham T, Bacher U, Werner O, Buch-

ner P, et al. Three-dimensional analysis of cleft palate

topology in newborn infants with reference to the cra-

nial skeleton. Cleft Palate Craniofac J 1998;35:379–95.

[12] Bacher M, Bacher U, Goz G, Pham T, Cornelius CP,

Speer CP, et al. Three-dimensional computer mor-

phometry of the maxilla and face in infants with Pierre

Robin sequence: a comparative study. Cleft Palate

Craniofac J 2000;37:292–302.

[13] Da Silveira A, Oliveira N, Gonzalez S, Shahani M,

Reisberg D, Daw J, et al. Modified nasal alveolar

molding appliance for management of cleft lip defect.

J Craniofac Surg 2003;14:700–3.

[14] Strauss RA, Weis BD, Lindauer SJ, Rebellato J, Isaac-

son RJ. Variability of facial photographs for use in

treatment planning for orthodontics and orthognathic

surgery. Int J Adult Orthodon Orthognath Surg 1997;

12:197–203.

[15] Vegter F, Hage JJ. Standardized facial photography of

cleft patients: just fit the grid? Cleft Palate Craniofac J

2000;37:435–40.

[16] Burke PH, Beard FH. Stereophotogrammetry of the

face: a preliminary investigation into the accuracy of

a simplified system evolved for contour mapping by

photography. Am J Orthod 1967;53:769–82.

[17] Burke PH, Hughes-Lawson CA. Stereophotogrammet-

ric study of growth and development of the nose. Am J

Orthod Dentofacial Orthop 1989;96:144–51.

[18] Aung SC, Ngim RC, Lee ST. Evaluation of the laser

scanner as a surface measuring tool and its accuracy

compared with direct facial anthropometric measure-

ments. Br J Plast Surg 1995;48:551–8.

[19] Bush K, Antonyshyn O. Three-dimensional facial an-

thropometry using a laser surface scanner: validation of

the technique. Plast Reconstr Surg 1996;98:226–35.

[20] Yamada T, Sugahara T, Mori Y, Sakuda M. Rapid

three-dimensional measuring system for facial surface

structure. Plast Reconstr Surg 1998;102:2108–13.

[21] Kusnoto B, Evans C. The reliability of a 3D surface

laser scanner for orthodontic applications. Am J Orthod

Dentofacial Orthop 2002;122:342–8.

[22] Ferrario VF, Sforza C, Poggio CE, Schmitz JH. Three-

dimensional study of growth and development of the

nose. Cleft Palate Craniofac J 1997;34:309–17.

[23] Ferrario VF, Sforza C, Schmitz JH, Miani Jr A, Serrao

G. A three-dimensional computerized mesh diagram

analysis and its application in soft tissue facial mor-

phometry. Am J Orthod Dentofacial Orthop 1998;114:

404–13.

[24] Ferrario VF, Sforza C, Poggio CE, Schmitz JH. Soft-

tissue facial morphometry from 6 years to adulthood:

a three-dimensional growth study using a new model-

ing. Plast Reconstr Surg 1999a;103:768–78.

[25] Ferrario VF, Sforza C, Schmitz JH, Santoro F. Three-

dimensional facial morphometric assessment of soft

tissue changes after orthognathic surgery. Oral Surg

Oral Med Oral Pathol Oral Radiol Endod 1999;88:

549–56.

[26] Nute SJ, Moss JP. Three-dimensional facial growth

A.C. Da Silveira et al / Clin Plastic Surg 31 (2004) 141–148148

studied by optical surface scanning. J Orthod 2000;

27:31–8.

[27] Ismail SF, Moss JP, Hennessy R. Three-dimensional

assessment of the effects of extraction and nonextrac-

tion orthodontic treatment on the face. Am J Orthod

Dentofacial Orthop 2002;121:244–56.

[28] Ismail SF, Moss JP. The three-dimensional effects of

orthodontic treatment on the facial soft tissues: a pre-

liminary study. Br Dent J 2002;192:104–8.

[29] Kuroda T, Motohashi N, Tominaga R, Iwata K. Three-

dimensional dental cast analyzing system using laser

scanning. Am J Orthod Dentofacial Orthop 1996;110:

365–9.

[30] Foong KW, Sandham A, Ong SH, Wong CW, Wang Y,

Kassim A. Surface laser scanning of the cleft palate

deformity: validation of the method. Ann Acad Med

Singapore 1999;28:642–9.

[31] Da Silveira AC, Daw Jr JL, Kusnoto B, Evans C,

Cohen M. Craniofacial applications of three-dimen-

sional laser surface scanning. J Craniofac Surg 2003;

14:449–56.

[32] Ferrario VF, Sforza C, Poggio CE, Serrao G. Facial

three-dimensional morphometry. Am J Orthod Dento-

facial Orthop 1996;109:86–93.

[33] Shanner DJ, Peterson AE, Beattie OB, Bamforth JS.

Assessment of soft tissue facial asymmetry in medi-

cally normal and syndrome-affected individuals by

analysis of landmarks and measurements. Am J Med

Genet 2000;93:143–54.

[34] Ferrario VF, Sforza C, Miani A, Tartaglia G. Cranio-

facial morphology by photographic evaluations. Am J

Orthod Dentofacial Orthop 1993;103:327–37.

[35] Farkas LG, Cheung G. Facial asymmetry in healthy

North American Caucasians: an anthropometric study.

Angle Orthod 1981;51:70–7.