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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 7  |  Issue : 2  |  Page : 99-107

Three-dimensional assessment of craniofacial parameters in subjects with cleft lip and palate: A cone-beam computed tomography study


1 Department of Plastic Surgery, K.G.M.U, Lucknow, Uttar Pradesh, India
2 Department of Orthodontics and Dentofacial Orthopaedics, F.O.D.S, K.G.M.U, Lucknow, Uttar Pradesh, India
3 Department of Oral Medicine and Radiology, F.O.D.S, K.G.M.U, Lucknow, Uttar Pradesh, India

Date of Submission20-Jan-2020
Date of Acceptance01-Jun-2020
Date of Web Publication31-Jul-2020

Correspondence Address:
Dr. Priyawati Moungkhom
Department of Plastic Surgery, K.G.M.U, Lucknow, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jclpca.jclpca_1_20

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  Abstract 


Objective: The objective of this study is to observe the differences in craniofacial parameters in subjects with cleft lip and palate and compare with normal subjects and also evaluate the association between chin deviation and asymmetry of face. Materials and Methods: Fifty cone-beam computed tomography (CBCT) scans (25 each) of the control group (Group I: normal) and study group (Group II: cleft lip and palate) subjects residing in Uttar Pradesh were obtained using care-stream CS 9300 3D system (care-stream Health, Inc. 2004). The digitizations and measurements were carried out in Dolphin Imaging software (Dolphin imaging version 11.9.07.24 premium). All subjects were within the age group of 15.1–18.9 years. Asymmetry indices (AI%) of the parameters were calculated as proposed by Habets et al. Results: Mean ± standard deviation of the differences in the variables between noncleft side (right side) and the cleft side (left) among the study group showed significant differences for Nasal width (P < 0.001), Ramus length (P < 0.004); mandibular body length (P < 0.021), total mandibular body length (P < 0.023), gonial angle (P < 0.034), nasal height (P < 0.043), maxillary dental width (P < 0.039), and mandibular dental width (P < 0.01). The asymmetric index value was >3% threshold value for nasal width (5.08% ± 5.72%) and for nasal height (−4.80 ± 10.81%) in the study group. Conclusion: From the study, it was observed that asymmetry exists in the region of the defect that lies in the area of the contracture. Mandibular asymmetry has also been expressed with deviation of chin to the cleft side. The asymmetry index (AI%) values were >3% threshold value only in the region of the defect.

Keywords: Asymmetry, cone-beam computed tomography, unilateral cleft lip and/palate


How to cite this article:
Moungkhom P, Nagar A, Tandon P, Singh GK, Singh A, Patil RK, Prasad V. Three-dimensional assessment of craniofacial parameters in subjects with cleft lip and palate: A cone-beam computed tomography study. J Cleft Lip Palate Craniofac Anomal 2020;7:99-107

How to cite this URL:
Moungkhom P, Nagar A, Tandon P, Singh GK, Singh A, Patil RK, Prasad V. Three-dimensional assessment of craniofacial parameters in subjects with cleft lip and palate: A cone-beam computed tomography study. J Cleft Lip Palate Craniofac Anomal [serial online] 2020 [cited 2020 Dec 1];7:99-107. Available from: https://www.jclpca.org/text.asp?2020/7/2/99/291133




  Introduction Top


Apparently symmetrical face is perceived as normal in the society. Any deviation from the normal becomes highlighted and is a social disadvantage. People born with congenital craniofacial deformities such as the cleft lip and palate becomes a psychosocial victim, especially during adolescence, as they are in the period of personality and relationship development and achieving independence.[1] It has been reported that the oral health-related quality of life is significantly low in young adults, that is, 15–18-year-old participants than in younger children, thereby, amplifying their social burden. During this period of adolescence, their growth is toward completion and skeletal discrepancy is no longer a moving target, therefore, if required the skeletal surgical corrections and nasolabial soft-tissue revisions are planned.[2]

According to the literature, asymmetry in the cleft lip and palate is secondary to the deformity and the result of the surgical repair of cleft lip and palate.[3] The development of mandibular asymmetry in cleft lip/palate may result due to true skeletal mandibular asymmetries, positional adaptation of jaw to asymmetric mandibular fossae, and functional adaptation to dento-alveolar and occlusal disharmonies.[4],[5] It has also been reported that asymmetries of the mandible, maxilla, and the cranial base structures lead to deviation of the chin.[6] Therefore, evaluating chin deviation is an important characteristic in the assessment of the asymmetry of the face.

Even though, the soft tissue may mask the skeletal asymmetry, hard-tissue evaluation is inescapable in the assessment of asymmetry. Three-dimensional (3D) evaluation is the recent addition in the field of orthodontics, which has showed significant advantages over two-dimensional cephalometric analysis. The advent of CBCT specifically dedicated to imaging the maxillofacial region has shifted from 2D data acquisition to a 3D approach.[7] 3D evaluation has showed significant advantages over 2D cephalometric analysis. CBCT allows determining the dental and skeletal craniofacial structures quickly, reliably, precisely, and accurately. CBCT provides high-quality images in short time with a lesser amount of radiation than conventional computed tomography. CBCT technology makes it feasible to achieve true (1:1) size images without magnification.[7]

Till date, there are relatively few 3D studies done on the craniofacial structures in unilateral cleft lip and/palate (UCLP) patients. Therefore, the objectives of the present study were: to observe the differences in craniofacial parameters in UCLP subjects and compare with normal subjects and also evaluate the association of asymmetry and chin deviation using CBCT.


  Materials and Methods Top


The present study was conducted on 50 CBCT scans of normal and UCLP subjects residing in Uttar Pradesh [Table 1]. The study subjects enrolled in the study were those, who got the CBCT done for the purpose of cleft lip and palate, and the normal subjects were selected from those, who got the CBCT done for the purpose of orthodontic diagnosis or temporomandibular joint (TMJ), pharyngeal space, and impacted tooth position assessment. An approval was obtained from the Institutional Ethics Committee. Informed consent from all the participants was obtained.
Table 1: Sample distribution

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Criteria for selection of control group: nonsyndromic adolescent subjects with skeletal Class I and average growth pattern; no obvious facial and dental abnormalities; no previous history of trauma/systemic diseases/neuromuscular deformities or any orthodontic treatment. Criteria for the selection of study group: patient with nonsyndromic cleft lip and palate with horizontal growth pattern, no previous history of trauma/systemic diseases/neuromuscular deformities, lip and palate reconstruction surgery or any orthodontic treatment.

Methods

All CBCT scans were carried out using Carestream CS9300 3D system (Carestream Health, Inc., 2004). The maxillofacial regions were scanned at 80 kV, 4.0 mA for 6.40 s with voxel size of 0.25 mm. The raw images of the patients were exported into Digital Imaging and Communications in Medicine files using the CS 3D imaging software. The digitizations and measurements were carried out in Dolphin Imaging software (dolphin imaging version 11.9.07.24 premium). The reference points [Figure 1], [Figure 2] and [Table 2] and planes[8],[9],[10] [Figure 3], [Figure 4] and [Table 3] and the measurements used in this study are described in [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9] and [Table 4].
Figure 1: Three-dimensional orthogonal reconstruction depicting mid-sagittal plane landmarks.

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Figure 2: Three-dimensional orthogonal reconstruction depicting bi-lateral landmarks on the noncleft and cleft side

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Table 2: Reference points used in the study

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Figure 3: Depicts the reference planes used in this study: mid-sagittal plane, Frankfort horizontal plane, coronal plane

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Figure 4: Depicts the reference planes used in this study: mandibular plane

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Table 3: Reference planes used in the study

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Figure 5: Depicts the measurements in relation to mid-sagittal plane

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Figure 6: Depicts the measurements in relation to Frankfort horizontal plane

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Figure 7: Depicts the measurements in relation to coronal plane

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Figure 8: Depicts the measurements in relation to mandibular plane

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Figure 9: Depicts the measurements of the mandible in lateral dimension

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Table 4: Measurements used in the study

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All the variables were measured and differences in the craniofacial parameters were observed in the subjects. Asymmetry indices (AI%) were calculated by the formula as proposed by Habets et al.: AI% = [(R − L)/(R + L)] ×100 in normal participants and AI% = [(Noncleft – Cleft)/(Noncleft + cleft)] ×100] in UCLP subjects.

Statistical methods

All the statistical analysis was performed using IBM SPSS Statistics V21.0, (IBM corporation, Armonk, New York, USA). Data were summarized as mean ± standard deviation the variables were compared between the groups by Student's t-test. Pearson correlation analysis was used to assess the association among variables. A two-sided P < 0.05 was considered statistically significant.


  Results Top


[Table 5] shows significant differences for nasal width (P < 0.001), ramus length (P < 0.004), mandibular body length (P < 0.021), total mandibular body length (P < 0.023), gonial angle (P < 0.034), nasal height (P < 0.043), maxillary dental width (P < 0.039), and mandibular dental width (P < 0.01) in Group II. The difference value between the right and the left side (noncleft and the cleft side) of nasal width (1.24) shows a positive value, indicating it is more deficient in the cleft side, maxillary height (−0.02), nasal height (−1.20), maxillary dental height (−0.10) shows a negative value indicating that the jugulare, lateral nasal, and mesio-bucccal cusp tip of molar point was at a larger distance to the mid-sagittal plane (MSP) on the cleft side; inter-condyle (−0.79), shows that condylar distance to MSP is increased in the cleft side; gonial angle (−0.88) shows that it is increased in the cleft side than that of the noncleft side. AI% was significant for inter-condyle distance (P = 0.026), nasal height (P = 0.026), sagittal position of lateronasal (P = 0.010), ramus length (P < 0.020), and body length (P < 0.043) in Group II. The AI% value was >3% threshold value for nasal width (5.08% ± 5.72%) and nasal height (−4.80% ± 10.81%) in Group II. No significant differences were observed in Group I.
Table 5: Intra-group comparison of mean differences and asymmetric index % between right and left side of Group I and between noncleft and cleft side of Group II for all the parameters

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Mean chin deviation in Group I was 0.228 ± 0.20 mm and 0.608 ± 1.21 mm in Group II [Table 6]. Significant correlation of chin deviation was observed with intercondyle (P < 0.022), ramus length (P < 0.020), mandibular body length (P < 0.020), and total mandibular length (P < 0.022) in Group II [Table 7]. The significant parameters were negatively correlated with chin deviation.
Table 6: Mean values and differences in the chin deviation

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Table 7: Correlation of chin deviation with various parameters

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  Discussion Top


Reference planes

Several methods have been put forward to construct the reference planes in the 3D cephalometric analysis. However, the best or most accurate planes have not been agreed to for craniofacial asymmetry. It was observed by Kwon et al., (2006)[11] that the cranial base structures were not relevant to the visual perception of craniofacial asymmetry and also not a dominant factor in explaining the degree of facial asymmetry. Therefore, they suggested that the cranial base may be used as a reference to determine the MSP for mild-to-moderate craniofacial asymmetries. Kyrkanides et al.,[12] in their study, observed that UCLP participants exhibiting cranial base asymmetry, did not significantly differ from those individuals without cleft. Therefore, cranial base structures can be relied on to construct the reference planes.

Considering the MSP, most 3D cephalometric analysis relies on midline structures to construct the MSP. Our study used the MSP according to the protocol suggested by Damstra et al., where the MSP passed through the Sella (S), Nasion (N) points and drawn perpendicular to the Frankfort Horizontal plane. It was considered to be most accurate clinically in resembling the morphometric values.

The Frankfort Horizontal plane was constructed through the bilateral Porion (Po) and Orbitale (Or) on the unaffected side of the UCLP participants (Orbitale on right side for the control group). Choi et al.,[13] in their study observed that Po tends to have symmetrical vertical locations in symmetrical face as well as in patients with facial asymmetry. Asymmetric location of external acoustic meatus was observed in participants with facial asymmetry and prominent maxillary occlusal cant. Therefore, our study has considered Porion to construct the FH plane. The coronal plane was constructed by passing through Ba, perpendicular to FH plane and MSP similar to that used by Lin et al.[9] in their study, and the mandibular plane was constructed by passing through the Menton (Me) and the Gonion (Go) bilaterally as used by Yang et al.,[10] in their study.

Normal subjects

The study showed no statistically significant differences (P > 0.05) between the right and the left side for all the parameters in Group I [Table 5]. These findings were consistent with the previous study by Sanders et al.,[14] who have observed that minor skeletal asymmetries existed in an otherwise symmetric patients clinically, where increased tendency for right side laterality was shown in normal adolescence. In the present study, the difference in value was not significant enough to be relevant although a positive value was expressed, signifying mild right side predominance, which was in consensus with the previous study.[14],[15],[16]

Unilateral cleft lip and/palate subjects

In UCLP participants, significant reduction in nasal chamber width, sagittal position, and increased vertical height on the cleft side was seen in consistent with previous studies. [5, 10, 17-19] These finding could be because of absence of nasal floor on the cleft side due to the presence of alveolar cleft. Farkas et al. (1993)[17] in their study had noticed that nostril floor width asymmetry was the most frequent among the residual deformities after surgery.

Significant difference was seen in maxillary dental width, with reduction on the cleft side, which was in consensus with the previous study.[5],[15] It has been suggested that these could be due to superadded pressure from buccal musculature on the defect side leading to mechanical displacement of the unsupported segment. Significant reduction in mandibular dental width was observed by Heidbuchel and Kuijpers-Jagtman[19] which have resulted as an adaptation to the maxillary arch. The maxillary dental height was similar on the cleft and noncleft sides, which was in accordance to the findings of Atherton.[20]

Morphological parameters of the mandible

The difference value of ramus length (1.31), mandibular body length (1.43), and total mandibular body length (0.83) were shorter on the cleft side in accordance with previous study.[5],[16] The difference value of Gonial angle (−0.88) was larger on the cleft side which was in agreement with that of Kurt et al., (2009),[21] 2011, Lin et al.[9]

Therefore, our study is in consensus with previous study by Kim et al.[22] which states that mandibular asymmetry may exist due to directed mandibular growth that may have compensated for the already existing asymmetries of the cranial base and the nasomaxillary complex. It may also have been exhibited by the cleft-related soft-tissue problems, which is increased muscular tension due to postoperative scarring.

Asymmetry index as proposed by Habetset al.

Asymmetry index (AI%) formula: [(R − L)/(R + L) ×100] was proposed by Habets et al.[23] He had described the formula while evaluating the Condylar and Ramal asymmetry in patients with TMDs. According to Habets et al., AI% >3% has been considered to support the existence of vertical asymmetry, as 3% index ratio may result if 1 cm change in head position results while obtaining Orthopantomogram (OPG). These formula have been used in our study to assess the asymmetry.

Significant differences were observed in Group II for nasal height, sagittal position of lateronasal, intercondyle distance, and mandibular body length. Nasal width AI% values were >3% threshold value in Group II (5.08% ± 5.72%). Previous studies[10] observed that significant differences were seen in the region of cleft and nasal chamber, as the major cause of this asymmetry may have occurred due to the lack of bone in this area. According to previous studies, asymmetry in the Condylar position to MSP results due to functional deviation secondary to occlusal characteristics and/or anatomic characteristics.[24] Significant asymmetry in ramus length and mandibular body length may have resulted due to functional adaptation of the mandible to the maxillary base. Although AI% values were <3% threshold value in the mandibular dimension.

Chin deviation

From previous studies, chin deviation of 4 mm and greater is regarded to be significant to indicate asymmetry clinically.[25],[26] Mean chin deviation in the study group was 0.608 mm ± 1.22 mm to the cleft side, not significant to indicate asymmetry. Although, the result was in consistent with that of previous studies by Son and Kim[27] (1.59 mm); Kim et al.[22] (1.94 mm). Nevertheless, it can be assumed that chin tends to deviate to the cleft side in UCLP participants.

Correlation of chin deviation with the parameters

Significant correlation of chin deviation with various parameters was observed in Group II with intercondyle (P < 0.022), ramus length (P < 0.020), mandibular body length (P < 0.020), and total mandibular length (P < 0.022) parameters. These findings were similar to the study of Lin et al.,[9] These parameters were negatively correlated with chin deviation, which was in the consensus with previous studies.[19] Yang et al.[10] and Lin et al.[9] in their study had observed that condylar position to MSP was correlated with horizontal mandibular asymmetry, with functional elements being the key factor. Therefore, it was observed that patients with cleft lip and palate do exhibit facial asymmetry, especially in the region of cleft as they are in the direct area of the contracture. Mandibular asymmetry has also been expressed with deviation of chin to the cleft side. Possibly, it may have developed as a compensatory mechanism to the existing deformity in the naso-maxillary complex.

As a matter of fact, asymmetry in the cleft lip and/palate participants is an inevitable finding. Had the surgeries not been undertaken at the initial ages, the existing asymmetry would have been much deteriorating and exhibit significantly decreased oral-health related quality of life with severely compromised functional, emotional, and psychosocial well-being.

However, for the findings to be superlative, larger sample of cleft patients has to be evaluated. To the best of our knowledge, very few studies on UCLP patients have been assessed by asymmetric index (AI%) formula as proposed by Habets et al. using CBCT. AI% formula is quite rewarding in appraising asymmetry. This index is efficacious as a diagnostic asset for evaluating asymmetry in UCLP patients and may be considered for interpretation.


  Conclusion Top


Following conclusions were drawn from the study:

  1. Significant differences in the mid-face region was observed in the region of pyriform aperture and the dentoalveolar region as they lie directly in the contraction area of the cleft
  2. Mandibular asymmetry has been expressed with deviation of chin to the cleft side. Mild mandibular asymmetry (P < 0.05) existed in individuals with chin deviation (0.608 ± 1.219 mm) which may or may not be clinically evident and was probably due to underlying asymmetry of the nasomaxillary complex or due to functional deviations of the mandible
  3. Asymmetry index was significant in the region of cleft
  4. Asymmetry index values were >3% threshold value only in the region of the nasal chamber.


Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Richman LC. Self-reported social, speech, and facial concerns and personality adjustment of adolescents with cleft lip and palate. Cleft Palate J 1983;20:108-12.  Back to cited text no. 1
    
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Laspos CP, Kyrkanides S, Tallents RH, Moss ME, Subtelny JD. Mandibular and maxillary asymmetry in individuals with unilateral cleft lip and palate. Cleft Palate Craniofac J 1997;34:232-9.  Back to cited text no. 4
    
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Smahel Z, Brejcha M. Differences in craniofacial morphology between complete and incomplete unilateral cleft lip and palate in adults. Cleft Palate J 1983;20:113-27.  Back to cited text no. 5
    
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Hwang HS, Hwang CH, Lee KH, Kang BC. Maxillofacial 3-dimensional image analysis for the diagnosis of facial asymmetry. Am J Orthod Dentofacial Orthop 2006;130:779-85.  Back to cited text no. 6
    
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8.
Damstra J, Fourie Z, De Wit M, Ren Y. A threedimensional comparison of a morphometric and conventional cephalometric midsagittal planes for craniofacial asymmetry. Clin Oral Investig 2012;16:285-94.  Back to cited text no. 8
    
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Lin Y, Chen G, Fu Z, Ma L, Li W. Conebeam computed tomography assessment of lower facial asymmetry in unilateral cleft lip and palate and non-cleft patients with class III skeletal relationship. PLoS One 2015;10:e0130235.  Back to cited text no. 9
    
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Kyrkanides S, Klambani M, Subtelny JD. Cranial base and facial skeleton asymmetries in individuals with unilateral cleft lip and palate. Cleft Palate Craniofac J 2000;37:556-61.  Back to cited text no. 12
    
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Choi YK, Park SB, Kim YI, Son WS. Three-dimensional evaluation of midfacial asymmetry in patients with nonsyndromic unilateral cleft lip and palate by cone-beam computed tomography. Korean J Orthod 2013;43:113-9.  Back to cited text no. 13
    
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Sanders DA, Chandhoke TK, Uribe FA, Rigali PH, Nanda R. Quantification of skeletal asymmetries in normal adolescents: Cone-beam computed tomography analysis. Prog Orthod 2014;15:26.  Back to cited text no. 14
    
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de Moraes ME, Hollender LG, Chen CS, Moraes LC, Balducci I. Evaluating craniofacial asymmetry with digital cephalometric images and cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2011;139:e523-31.  Back to cited text no. 16
    
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Farkas LG, Hajnis K, Posnick JC. Anthropometric and anthroposcopic findings of the nasal and facial region in cleft patients before and after primary lip and palate repair. Cleft Palate Craniofac J 1993;30:1-2.  Back to cited text no. 17
    
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Suri S, Utreja A, Khandelwal N, Mago SK. Craniofacial computerized tomography analysis of the midface of patients with repaired complete unilateral cleft lip and palate. Am J Orthod Dentofacial Orthop 2008;134:418-29.  Back to cited text no. 18
    
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Heidbuchel KL, Kuijpers-Jagtman AM. Maxillary and mandibular dental-arch dimensions and occlusion in bilateral cleft lip and palate patients from 3 to 17 years of age. Cleft Palate Craniofac J 1997;34:21-6.  Back to cited text no. 19
    
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Atherton JD. Morphology of facial bones in skulls with unoperated unilateral cleft palate. Cleft Palate J 1967;4:18-30.  Back to cited text no. 20
    
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Kurt G, Bayram M, Uysal T, Ozer M. Mandibular asymmetry in cleft lip and palate patients. Eur J Orthod 2010;32:19-23.  Back to cited text no. 21
    
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Kim KS, Son WS, Park SB, Kim SS, Kim YI. Relationship between chin deviation and the position and morphology of the mandible in individuals with a unilateral cleft lip and palate. Korean J Orthod 2013;43:168-77.  Back to cited text no. 22
    
23.
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]



 

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