ORIGINAL ARTICLE

Condylar and ramal vertical asymmetry inadolescent patients with cleft lip and palateevaluated with cone-beam computedtomography

Mevlut Celikoglu,a Koray Halicioglu,b Suleyman K. Buyuk,c Ahmet E. Sekerci,d and Faruk I. Ucare

Trabzon, Bolu, and Kayseri, Turkey

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Introduction: The aims of this study were to evaluate condylar and ramal mandibular vertical asymmetry in apatient group affected by unilateral (UCLP) and bilateral (BCLP) cleft lip and palate, and to compare the findingswith awell-matched control groupwith normal occlusion.Methods: The study groups included 20UCLP patients(12 male, 8 female), 21 BCLP patients (12 male, 9 female), and a control group of 21 subjects with normal oc-clusion (10male, 11 female). Measurements of condylar, ramal, and condylar plus ramal heights and asymmetryindexes were examined on cone-beam computed tomography images. One-way analysis of variance was usedto determine potential statistical differences among the groups for condylar, ramal, and condylar plus ramalasymmetry index measurements. The post-hoc Tukey HSD test was used to determine individual differences.Results: No investigated group showed a statistically significant sex difference for any asymmetry index(P.0.05). There was a statistically significant difference between the normal and cleft sides in the ramal heightand ramal plus condylar height measurements in the UCLP group (P 5 0.004 and P 5 0.006, respectively).The Tukey HSD test showed a statistically significant difference between the UCLP and BCLP groups in termsof ramal asymmetry index values (P 5 0.018). Conclusions: The ramal height and ramal plus condylarheight measurements were significantly lower in the cleft side in the UCLP patients, and there was a statisticallysignificant difference in ramal asymmetry index values between the patients affected by UCLP and BCLP.(Am J Orthod Dentofacial Orthop 2013;144:691-7)

Patients affected by cleft lip and palate (CLP)exhibit different growth patterns of the dento-maxillofacial tissues than do their normal peers1

and commonly have anterior and posterior crossbite ten-dencies caused by scarring.2 The crossbite side, espe-cially unilateral posterior crossbite, is related to

ciate professor, Department of Orthodontics, Faculty of Dentistry, Karade-chnical University, Trabzon, Turkey.tant professor, Department of Orthodontics, Faculty of Dentistry, AbantBaysal University, Bolu, Turkey.arch assistant, Department of Orthodontics, Faculty of Dentistry, Erciyesrsity, Kayseri, Turkey.tant professor, Department of Oral and Maxillofacial Radiology, Faculty ofstry, Erciyes University, Kayseri, Turkey.te practice, Kayseri, Turkey.thors have completed and submitted the ICMJE Form for Disclosure of Po-l Conflicts of Interest, and none were reported.ss correspondence to: Mevlut Celikoglu, Department of Orthodontics, Fac-f Dentistry, Karadeniz Technical University, Trabzon, Turkey; e-mail,tcelikoglu@hotmail.com.itted, February 2013; revised and accepted, July 2013.5406/$36.00ight � 2013 by the American Association of Orthodontists./dx.doi.org/10.1016/j.ajodo.2013.07.009

asymmetrical muscular function.3 Prolongation ofabnormal muscular functions can cause changes in thegrowth center at the temporomandibular joint4 becausethe condyle is one of the most sensitive areas to occlusalchanges.5

Some studies6,7 have reported mandibular asymmetryin patients affected by CLP, whereas others,8-10 throughthe use of different radiographs and assessmenttechniques, have claimed that patients affected by CLPhave no asymmetric mandible. For the first timereported in the literature, Habets et al11,12 applied amethod to assess vertical mandibular asymmetry. Thisnew method, which compares the vertical height of theright and left condyles and rami, has been used bysome researchers to compare condylar asymmetry inunilateral13,14 and bilateral14,15 posterior crossbitepatients, patients with temporomandibular disorders,11

early bilateral first molar extraction patients,16 and pa-tients with Class II17,18 and Class III18,19 malocclusions.Recently, Kurt et al20 found no statistically significantdifferences among unilateral (UCLP) and bilateral

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(BCLP) cleft lip and palate groups and a control groupwith normal occlusion, using the method of Habetset al.11,12

All of these mentioned studies on vertical mandibularasymmetry were performed with panoramic radiographs,which enable scanning of end-to-end structuresof the entire dental system with relatively limited radia-tion doses and reduced financial costs to patientsand health service providers.21,22 Nevertheless, thereare some disadvantages to panoramic radiographs,such as inconstant magnification, image distortion,and vertical measurements that might be affected bythe patient's head position.23 However, cone-beamcomputed tomography (CBCT) technology makes itfeasible to achieve true (1:1 size) images without magni-fication and with a relatively lower radiation dose andlower cost than with computed tomography.24,25

Although studies on vertical condylar asymmetry haveincreased in recent years, to date, no study has been donewith CBCT images to investigate condylar asymmetry ingroups of UCLP and BCLP patients and compare themwith a normal occlusion sample. Therefore, in this study,we aimed to determine whether there is an increase incondylar asymmetry associated with patients affected byUCLP and BCLP compared with an unaffected controlpopulation, using CBCT images according to the methoddescribed by Habets et al.11,12

MATERIAL AND METHODS

This study was carried out on the CBCT radiographsselected from the archives of the Departments of Oraland Maxillofacial Radiology and Orthodontics of theFaculty of Dentistry, Erciyes University, Kayseri, Turkey.The CBCT scans of the patients included in this studywere part of the diagnostic records collected for pa-tients with impacted teeth or those who required or-thodontic treatment; the patients were not exposedto any additional radiation. Therefore, approval fromthe ethics committee was not required for this retro-spective archive study. In addition, as a usual protocol,all patients (or parents) signed an informed consentagreeing to the use of the patients' data for scientificstudies.

The patientswere divided into 3 groups: (1) 20patients(12 male, 8 female) affected by UCLP, (2) 21 patients (12male, 9 female) affected by BCLP, and (3) 21 patients (10male, 11 female) as the control group. Subjects in the con-trol group with normal occlusion met the followingcriteria, as suggested by Kurt et al20: (1) Class I canineand molar relationships with minor crowding, normalgrowth, and normal development, including normal skel-etal relationship and facial balance; (2) all teeth present

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except third molars; (3) no history of trauma, previous or-thodontic or prosthodontic treatment, or maxillofacialsurgery; and (4) no significant medical history.

All images were obtained with the patient in the su-pine position using CBCT (NewTom 5G; QR srl, Verona,Italy). Scanning time was 18 seconds, collimation heightwas 13 cm, exposure time was 3.6 seconds, and voxelsize was 0.3 mm3. Digital Imaging and Communicationsin Medicine (DICOM) files obtained from the CBCT scanswere reconstructed using NNT viewer software (QR S.r.l.,Verona, Italy). All measurements were made by 1 author(S.K.B.). In addition, the cervical vertebra maturationstages of all patients were determined according to themethod of Hassel and Farman.26

On both sides, the most posterior points of thecondyle and ramus of the mandible were marked asthe X and Y points. A line was drawn through X and Yand called the A-line. Another line, called the B-line,was drawn from the most superior points of the condyleperpendicular to the A-line. The confluence of the A-lineand B-line was called point Z. The distance betweenpoints X and Z was measured as condylar height. In addi-tion to this measurement, the distance between X and Yand the distance between Z and Y were measured asramus height and condylar plus ramus height, respec-tively (Fig).

Finally, the vertical mandibular asymmetry indexes ofthe condyle, ramus, and condyle plus ramus were calcu-lated using the following formula, developed by Habetset al11,12:Asymmetry index (%): [(Right� Left)/ (Right1 Left)]3 100

Statistical analysis

Two weeks after the first measurements, 20 randomlyselected CBCT images were retraced and remeasured bythe same author. The method error coefficient wascalculated with Dahlberg's formula.27 Dahlberg'smethod error values were within acceptable limits(range, 0.409-0.954). In addition, the difference be-tween the 2 tracings was tested for significance with apaired t test; no significant difference was found(P .0.05), confirming the intraobserver reliability ofthe measurements.

Data regarding the asymmetry measurements werecomputed. The normality test of the Shapiro-Wilks andthe Levene variance homogeneity test were applied tothe data; all data were found to be normally distributed.Thus, the comparisons among the groups and sexes wereanalyzed using parametric tests. The Student t test wasused to compare the sexes, and 1-way analysis of vari-ance (ANOVA) was used to compare the asymmetry in-dexes among the UCLP, BCLP, and control groups. The

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Table I. Demographic features of the patients in cleft and normal groups

Group Sex Age (y) Number Sex comparison UCB BCB

Cervical vertebral maturation (CVM) stage

1 2 3 4 5 6UCLP Male 15.49 6 3.84 12 NS 3 2 2 3 2 1 2 2

Female 12.42 6 3.36 8 2 1 4 0 3 0 0 1Total 14.26 6 3.88 20 5 3 6 3 5 1 2 3

BCLP Male 14.38 6 2.48 12 NS 4 6 3 2 2 3 1 1Female 14.63 6 2.59 9 3 4 0 1 1 1 2 4Total 14.49 6 2.47 21 7 10 3 3 3 4 3 5

Normal occlusion Male 13.85 6 2.22 10 NS 0 0 0 2 1 4 3 0Female 14.69 6 2.26 11 0 0 0 1 2 4 2 2Total 14.29 6 2.23 21 0 0 0 3 3 8 5 2

Group comparison NS NS

UCLP, Unilateral cleft lip and palate;BCLP, bilateral cleft lip and palate;UCB, unilateral crossbite; BCB, bilateral crossbite;NS, not significant. CVMstages according to Hassel and Farman26: CVM1, initiation of adolescent growth; CVM2, acceleration of adolescent growth; CVM3, transition ofadolescent growth; CVM4, deceleration of adolescent growth; CVM5, maturation of adolescent growth; CVM6, completion of adolescent growth.

Fig. Measuring method according to Habets et al.11,12

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Tukey HSD post-hoc test was performed to determineindividual differences. In addition, a paired t test wasused to determine possible statistical differences be-tween the sides for condylar height, ramal height, andcondylar height plus ramal height measurements in allgroups.

All statistical analyses were performed with SPSSsoftware (version 15.0 for Windows; SPSS, Chicago,Ill); P\0.05 was considered statistically significant.

RESULTS

Table I shows descriptive data of the patients in thestudy. Sex distribution and chronologic ages in all

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groups were well matched (tested by chi-square and 1-way ANOVA, respectively; P .0.05 for both tests). Thechronologic ages of the patients affected by UCLP andBCLP and the normal occlusion controls were 14.26 63.88, 14.49 6 2.47, and 14.29 6 2.23 years, respec-tively.

The descriptive mandibular asymmetry indexes forboth sexes were calculated separately in the normal oc-clusion and CLP patient groups to investigate the rela-tionship between the sexes. Because no statisticallysignificant differences were found for these meanvalues, the data were pooled for further analyses(Table II).

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Table II. Comparison of mandibular asymmetry indexes between the sexes

Group Variable (%)

Male (n 5 34) Female (n 5 28)

PMean SD Mean SDUCLP (n 5 20) (F/M, 8/12) CAI 10.87 8.89 11.59 7.57 0.851

RAI 4.30 5.73 3.72 2.29 0.791CRAI 3.83 5.50 2.90 1.70 0.649

BCLP (n 5 21) (F/M, 9/12) CAI 8.81 8.36 6.88 7.95 0.598RAI 1.53 1.85 1.49 1.89 0.954CRAI 1.47 1.57 1.63 1.81 0.827

Normal occlusion (n 5 21) (F/M, 11/10) CAI 11.00 11.68 13.12 7.76 0.627RAI 2.50 1.21 2.48 1.16 0.970CRAI 1.98 1.75 2.19 1.64 0.788

UCLP, Unilateral cleft lip and palate; BCLP, bilateral cleft lip and palate; CAI, condylar asymmetry index; RAI, ramal asymmetry index; CRAI,condylar plus ramal asymmetry index; F/M, female/male ratio; P, results of Student t test comparing the sexes.

Table III. Comparison of the height measurements for sides in the normal, UCLP, and BCLP groups

Variable

UCLP BCLP Normal occlusion

Normal side Cleft side

P

Right side Left side

P

Right side Left side

PMean (mm) Mean (mm) Mean (mm) Mean (mm) Mean (mm) Mean (mm)CH 3.41 6 0.95 3.56 6 0.84 0.489 3.41 6 0.72 3.66 6 0.81 0.148 4.41 6 0.89 4.01 6 0.83 0.156RH 42.70 6 5.63 40.24 6 6.76 0.004 39.34 6 3.79 39.42 6 3.41 0.839 42.67 6 4.76 42.07 6 5.26 0.252CH 1 RH 46.11 6 6.01 43.80 6 7.19 0.006 42.75 6 3.99 43.08 6 3.98 0.442 47.08 6 5.11 46.08 6 5.54 0.054

UCLP, Unilateral cleft lip and palate; BCLP, bilateral cleft lip and palate; CH, condylar height; RH, ramal height; CR 1 RH, condylar plus ramalheight; P, results of paired-samples t test.

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Means, standard deviations, and statistical results ofpaired t tests comparing the condylar height, ramalheight, and condylar height plus ramal height measure-ments of the normal and cleft sides in the UCLP group,and the left and right sides in the BCLP and the normalocclusion groups are shown in Table III. There were nostatistically significant differences in the condylarheight, ramal height, and condylar height plus ramalheight measurements between the right and left sidesin the BCLP and control groups; however, there werestatistically significant differences in ramal height andcondylar height plus ramal height measurements be-tween the normal and cleft sides in the UCLP groups(P 5 0.004 and P 5 0.006, respectively). The ramalheight values were 42.70 6 5.63 mm in the normalside and 40.246 6.76 mm in the cleft side; the condylarheight plus ramal height values were 46.11 6 6.01 mmin the normal side and 43.80 6 7.19 mm in the cleftside.

The results of the ANOVA showed no statisticallysignificant differences in the condylar asymmetryindex or the condylar plus ramal asymmetry index mea-surements among the groups, whereas the ramal asym-metry index was statistically significantly different(P 5 0.023). The Tukey HSD test showed a statistically

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significant difference in the ramal asymmetry index be-tween the UCLP and BCLP groups (P 5 0.018). Theramal asymmetry index values were 4.07% 6 4.59%in the UCLP group and 1.52% 6 1.82% in the BCLPgroup (Table IV).

DISCUSSION

Panoramic films have often been used by investiga-tors who performed condylar13-20,28 and mandi-bular29,30 asymmetry studies. However, CBCT is themost accurate and most reliable available techniquefor determination, without magnification of asym-metries10,24,31 and with a relatively low radiation doseand relatively low cost.11,30 Two-dimensional data ob-tained from CBCT are more reliable than conventional2-dimensional radiographs in terms of magnification.Thus, in our study, CBCT images were used for theassessment of mandibular vertical asymmetry. This studyis the first in the literature to use CBCT to investigatevertical condylar and ramal asymmetry with the methodof Habets et al11,12 in patients affected by UCLP andBCLP. The reproducibility of vertical measurements onpanoramic films is admissible if the patient's head iscorrectly positioned in the cephalostat.32 According toHabets et al, a 3% index ratio can result from a 1-cm

Journal of Orthodontics and Dentofacial Orthopedics

Table IV. Comparisons of mandibular asymmetry index values among the groups

Asymmetry index Group n Mean (%) P G1-G2 G1-G3 G2-G3CAI UCLP 20 11.16 6 8.18 0.280 .474 .934 .278

BCLP 21 7.98 6 8.04Normal occlusion 21 12.11 6 9.63

RAI UCLP 20 4.07 6 4.59 0.023 0.018 .197 .525BCLP 21 1.52 6 1.82Normal occlusion 21 2.49 6 1.16

CRAI UCLP 20 3.46 6 4.33 0.089 .082 .273 .800BCLP 21 1.54 6 1.64Normal occlusion 21 2.09 6 1.66

UCLP, Unilateral cleft lip and palate and (G1); BCLP, bilateral cleft lip and palate and (G2); G3, normal occlusion; CAI, condylar asymmetry index;RAI, ramal asymmetry index; CRAI, condylar plus ramal asymmetry index; P, results of 1-way ANOVA comparing the 3 groups.

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change in head position while the panoramic film is be-ing taken; thus, asymmetry index (condylar asymmetry,ramal asymmetry, and condylar plus ramal asymmetryindexes) values greater than 3% should be approved asposterior mandibular vertical asymmetry. In this study,we examined this hypothesis because the patient'shead position is not an assessment criterion when usingCBCT.

The condylar asymmetry index values of all groupswere high (control group, 12.11% 6 9.63%; UCLP,11.16% 6 8.18%; BCLP, 7.98% 6 8.04%) whencompared with the 3% threshold value of Habetset al.11,12 Turp et al33 mentioned that mild condyleand ramus asymmetries are part of the biologic varia-tions of humans. Nevertheless, all patients in this study,both with and without CLP, had severely asymmetricmandibles according to the condylar asymmetry indexmeasurements. Furthermore, Uysal et al,14 Haliciogluet al,16 Saglam,18 and Kurt et al20 found condylar asym-metry index values of 7.57%6 8.39%, 7.04%6 6.79%,7.96% 6 6.73%, and 9.95% 6 10.42%, respectively, intheir normal occlusion groups. These studies have simi-larly high condylar asymmetry index values, even thoughthey were performed using panoramic films. Therefore,investigators who are interested in condylar asymmetryshould revise the 3% condylar asymmetry indexthreshold value of Habets et al.11,12

Kurt et al20 reported that the ramal height andcondylar height plus ramal height measurements oftheir CLP patient groups were approximately 10 mmgreater than those of a peer control group with normalocclusion, and they observed that there were statisti-cally significant condylar height differences in theBCLP patients. We need to take into account condylarasymmetry studies performed on patients with poste-rior crossbites because patients affected by CLPcommonly have unilateral or bilateral posterior cross-bites. Most of the patients in our study had unilateralor bilateral posterior crossbites (Table I). Kilic et al15

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reported that condylar height, ramal height, andcondylar height plus ramal height measurements onthe unilateral crossbite side were smaller than thoseon the noncrossbite side. However, Kiki et al13 andUysal et al14 found no significant differences betweenthe right and left sides in the bilateral posterior cross-bite group. In our study, condylar height, ramal height,and condylar height plus ramal height measurementswere close to each other in both sides of all groupsexcept the UCLP group. Ramal height and condylarheight plus ramal height measurements were statisti-cally lower in the cleft side of the UCLP groups whencompared with the normal side. In addition, the cleftsides in the UCLP and BCLP groups were approximately2.5 to 3 mm smaller when compared with the normalsides in the UCLP and control groups. This finding isinteresting when compared with the findings of Kurtet al, who stated that the ramal height and condylarheight plus ramal height measurements of their CLPpatients were approximately 10 mm greater than thoseof patients with normal occlusion. We think that thisdifference between our study and that of Kurt et al isdue to the use of panoramic films in their study andCBCT in our study.

In another study performed with CBCT, Veli et al10

reported that ramal heights measured using differentanatomic landmarks did not show statistically signifi-cant differences between sides in their UCLP and normalocclusion groups. We attribute the differences betweenour results and those of earlier studies to the use ofdifferent landmarks for ramal-height assessment.10,24

The method we used is different in that it actuallyundermeasures the full condylar height andovermeasures the actual anatomic ramus. In addition,a recent study of unilateral crossbite patients reporteda statistically significant decrease in the crossbite sidescompared with the normal sides.15 This agrees withour findings because unilateral crossbite is almost al-ways seen in UCLP patients.

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696 Celikoglu et al

Kurt et al20 found no statistically significant differ-ences in condylar asymmetry, ramal asymmetry, orcondylar plus ramal asymmetry index values amongthe UCLP, BCLP, and control groups. In our study, nostatistically significant differences in the condylar asym-metry index or condylar plus ramal asymmetry indexvalues were found. However, we found a statistically sig-nificant difference in the ramal asymmetry index be-tween the UCLP and BCLP groups. The differencesbetween our findings and those of Kurt et al might bedue to the different film techniques used in the studiesbecause CBCT images provide more valuable informa-tion than do panoramic films. It is difficult to compareour findings with those of previous studies of patientsaffected by CLP to determine condylar asymmetrybecause no studies have investigated condylar asymme-try in CLP patients with 2-dimensional data obtainedfrom CBCT and the method of Habets et al.12

CONCLUSIONS

1. The condylar asymmetry index values of allgroups were significantly higher when comparedwith the 3% threshold value of Habets et al,11,12

but comparisons among the groups were notstatistically significant. Therefore, the 3%threshold value for the condylar asymmetry indexmeasurement must be examined further.

2. There were statistically significant differences in theramal height and condylar height plus ramal heightmeasurements between the normal and cleft sidesof the UCLP group (P 5 0.004 and P 5 0.006,respectively).

3. The ramal asymmetry index values of the patientsaffected by UCLP and BCLP were statisticallydifferent (P 5 0.018).

4. Further investigations with larger samples, evalu-ated in 3 dimensions, and correlating with occlusalasymmetry are needed to confirm the results of thisstudy.

REFERENCES

1. Bugaighis I, O'Higgins P, Tiddeman B, Mattick C, Ben Ali O,Hobson R. Three-dimensional geometric morphometrics appliedto the study of children with cleft lip and/or palate from the NorthEast of England. Eur J Orthod 2010;32:514-21.

2. Shetye PR, Evans CA. Midfacial morphology in adult unoperatedcomplete unilateral cleft lip and palate patients. Angle Orthod2006;76:810-6.

3. Ferrario VF, Sforza C, Serrao G. The influence of crossbite on thecoordinated electromyographic activity of human masticatorymuscles during mastication. J Oral Rehabil 1999;26:575-81.

4. Graber TM. Orthodontics—principles and practice. Philadelphia:W. B. Saunders; 1967. p. 470 and 674-5.

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5. Pirttiniemi P, Kantomaa T, Salo L, Tuominen M. Effect of reducedarticular function on deposition of type I and type II collagens inthe mandibular condylar cartilage of the rat. Arch Oral Biol1996;41:127-31.

6. Ishiguro K, KrogmanWM, Mazaheri M, Harding RL. A longitudinalstudy of morphological craniofacial patterns via P-A x-ray head-films in cleft patients from birth to six years of age. Cleft PalateJ 1976;13:104-26.

7. Horswell BB, Levant BA. Craniofacial growth in unilateral cleft lipand palate: skeletal growth from eight to eighteen years. Cleft Pal-ate J 1988;25:114-21.

8. Smahel Z, Brejcha M. Differences in craniofacial morphology be-tween complete and incomplete unilateral cleft lip and palate inadults. Cleft Palate J 1983;20:113-27.

9. Laspos CP, Kyrkanides S, Tallents RH, Moss ME, Subtelny JD.Mandibular asymmetry in noncleft and unilateral cleft lip and pal-ate individuals. Cleft Palate Craniofac J 1997;34:410-6.

10. Veli I, Uysal T, Ucar FI, Eruz M, Ozer T. Cone-beam computed to-mography assessment of mandibular asymmetry in unilateral cleftlip and palate patients. Korean J Orthod 2011;41:431-9.

11. Habets LL, Bezuur JN, Naeiji M, Hansson TL. The orthopantomo-gram, an aid in diagnosis of temporomandibular joint problems. II.The vertical symmetry. J Oral Rehabil 1988;15:465-71.

12. Habets LL, Bezuur JN, VanOoij CP, Hansson TL. The orthopanto-mogram, an aid in diagnosis of temporomandibular joint prob-lems. I. The factor of vertical magnification. J Oral Rehabil 1987;14:475-80.

13. Kiki A, Kilic N, Oktay H. Condylar asymmetry in bilateral posteriorcrossbite patients. Angle Orthod 2007;77:77-81.

14. Uysal T, Sisman Y, Kurt G, Ramoglu SI. Condylar and ramal verticalasymmetry in unilateral and bilateral posterior crossbite patientsand a normal occlusion sample. Am J Orthod Dentofacial Orthop2009;136:37-43.

15. Kilic N, Kiki A, Oktay H. Condylar asymmetry in unilateral posteriorcrossbite patients. AmJOrthodDentofacial Orthop 2008;133:382-7.

16. Halicioglu K, Celikoglu M, Caglaroglu M, Buyuk SK, Akkas I,Sekerci AE. Effects of early bilateral mandibular first molar extrac-tion on condylar and ramal vertical asymmetry. Clin Oral Investig2012;17:1557-61.

17. Miller VJ, Smidt A. Condylar asymmetry and age in patients withan Angle's Class II division 2 malocclusion. J Oral Rehabil 1996;23:712-5.

18. Saglam AM. The condylar asymmetry measurements in differentskeletal patterns. J Oral Rehabil 2003;30:738-42.

19. Miller VJ, Bodner L. Condylar asymmetry measurements in pa-tients with an Angle's Class III malocclusion. J Oral Rehabil1997;24:247-9.

20. Kurt G, BayramM, Uysal T, Ozer M. Mandibular asymmetry in cleftlip and palate patients. Eur J Orthod 2010;32:19-23.

21. Rushton VE, Horner K. The use of panoramic radiology in dentalpractice. J Dent 1996;24:185-201.

22. Tugnait A, Clerehugh DV, Hirschmann PN. Survey of radiographicpractices for periodontal disease in UK and Irish dental teachinghospitals. Dentomaxillofac Radiol 2000;29:376-81.

23. Kitai N, Mukai Y, Murabayashi M, Kawabata A, Washino K,Matsuoka M, et al. Measurement accuracy with a new dentalpanoramic radiographic technique based on tomosynthesis. AngleOrthod 2013;83:117-26.

24. Veli I, Uysal T, Ozer T, Ucar FI, Eruz M. Mandibular asymmetry inunilateral and bilateral posterior crossbite patients using cone-beam computed tomography. Angle Orthod 2011;81:966-74.

25. Rossini G, Cavallini C, Cassetta M, Galluccio G, Barbato E. Locali-zation of impacted maxillary canines using cone beam computed

Journal of Orthodontics and Dentofacial Orthopedics

Celikoglu et al 697

tomography. Review of the literature. Ann Stomatol (Roma) 2012;3:14-8.

26. Hassel B, Farman AG. Skeletal maturation evaluation using cervicalvertebrae. Am J Orthod Dentofacial Orthop 1995;107:58-66.

27. Dahlberg G. Statistical methods for medical and biological stu-dents. New York: Interscience Publications; 1940.

28. Sezgin OS, Celenk P, Arici S. Mandibular asymmetry in differentocclusion patterns. Angle Orthod 2007;77:803-7.

29. Ramirez-Ya~nez GO, Stewart A, Franken E, Campos K. Prevalence ofmandibular asymmetries in growing patients. Eur J Orthod 2011;33:236-42.

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30. Van Elslande DC, Russett SJ, Major PW, Flores-Mir C. Mandibularasymmetry diagnosis with panoramic imaging. Am J Orthod Den-tofacial Orthop 2008;134:183-92.

31. Sanders DA, Rigali PH, Neace WP, Uribe F, Nanda R. Skeletal anddental asymmetries in Class II subdivision malocclusions usingcone-beam computed tomography. Am J Orthod Dentofacial Or-thop 2010;138:542.e1-20.

32. Yale SH. Radiographic evaluation of the temporomandibular joint.J Am Dent Assoc 1969;79:102-7.

33. T€urp JC, Alt KW, VachW, Harbich K.Mandibular condyles and ramiare asymmetric structures. Cranio 1998;16:51-6.

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