Scand J Plast Reconstr I h n d d h r n 26.177-183. 1992
CEPHALOMETRIC MEASUREMENTS I N PATIENTS WITH PIERRE ROBIN SYNDROME A N D ISOLATED CLEFT PALATE
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
Sirpa H. Laitinen' and Reijo E. Rants'.* From the Department of ' Pedodontics und Orthodontics, University of Helsinki and the Department of 2Plustic Surgery, Cleft Center, Helsinki University Centrul Hospital, Finland (Submitted for publication March 27, 1991)
Abstract. To compare craniofacial structure and growth, two standard lateral cephalograms of 35 children with Pierre Robin syndrome and 30 age and sex matched children with isolated cleft palate were taken at two different ages. The mean (SD) age of the children with Pierre Robin syndrome was 9.5 (3.0) years and of the children with isolated cleft palate 7.1 ( I. 1 ) years at the start of the follow up period. The follow up time in the first group was 4.3 (1.6) and in the second group 3.8 (2.7) years. There were no significant differences between the groups in the shape of the cranial base or the maxilla. The main differences were in the mandible, which showed more recession among those with Pierre Robin syndrome. There was a significant correlation between the shape of the maxilla and that of the mandible in that group, but not in the group with isolated cleft palate. During the follow up period there were no significant differences between the two groups in the rate of growth of the jaws. The association between the maxilla and the mandible (ss-n-sm) remained unchanged, or increased, or decreased with equal frequency in both groups. There was no catch up mandibular growth among the children with Pierre Robin syndrome. Ke,v tvords: Pierre Robin syndrome, isolated cleft palate, craniofacial growth, craniofacial morphology.
The Pierre Robin syndrome refers to a combination of micrognathia, glossoptosis, and cleft palate, which may occur as an isolated defect or as part of a broader pattern of malformations (4-6,9). The aetiology is complex (5), and it has been suggested that it may be a non specific symptom complex rather than a specific syndrome (4). The growth pattern of children with Pierre Robin syndrome varies depending on the aetiology. In the newborn period it clearly differs from the isolated cleft palate with regard to the maxillary overjet, but not to the width of the cleft ( 1 I ) ; the mandible is the structure that varies (18,21). Moreover, many authors accept that substantial spontaneous correction
in the facial profile will occur within the first few years of life ( 11, 13- 15, 17, 25). Marcovic ( 13) showed that the normalisation in the relationship of the jaws occurred after the age of 10 years, and a retrognathic maxilla was a common finding in his study of 15 children with Pierre Robin syndrome. Randall et al. (17) showed three well defined growth patterns in 18 1 year old children with the syndrome: almost normal mandibular size and position; persistent micrognathia; and a tendency to forward protrusion and achievement of a fairly normal anterior relationship. Closer examination of the mandible in such patients shows the pathognomic shape and proportion. The gonial angle is obtuse, the condyle extends distally from the ramus, and the ramus to body proportion deviates because of the reduction in the body length (16.25). The features can be retained from infancy into later years, but disappear with age ( I I , 13, 15- 17,25). The slope of both maxilla and mandible of Pierre Robin syndrome is anteriorly downwards, and the gonial angle is more obtuse than in patients with isolated cleft palate (18). The cranial base angle in patients with Pierre Robin syndrome is nearly the same or larger than that in patients with isolated cleft palate ( 1 I), in whom it either does not differ from the mean among subjects without clefts (2, 7, 18), or may show greater flexion of the angle ( 12). The aim of this follow up study was to compare the craniofacial structure and growth in children with the Pierre Robin syndrome with that among children with isolated cleft palate. PATIENTS AND METHODS We studied 35 patients with Pierre Robin syndrome (group I); there were 17 boys and 18 girls aged from 4-20 Scund
J Plus: Reconsrr Hund Surg 26
178
S. H . Luitinen and R. E. Ranta
Table I. Other congenital anomalies in the two groups
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
Pierre Robin syndrome ( n = 35) Hypertelorism Myopia Heart murmur Talipes Mandibular tumor Protruding ears Central depression of lower lip Van der WoudeS syndrome Hypoplastic nose Uveal coloboma Other Total
Isolated cleft palate (n = 30)
2 0 0 0
0
Isolated cleft palate (11 = 30)
9. I 4.1-16.0
7. I 5.0- 16.4
13.3 7.6-20.0
12.4 7.4-21.8
4.3 1 . 1 -7.0
3.8 1.0- 12.7
9
years. The mean (SD)follow up period was 4.3 ( I .6) years. The diagnostic criteria were micrognathia, cleft palate, and various degrees of respiratory difficulties caused by glossoptosis in the immediate neonatal period. Other distinct syndromes were not included in this group or in the control group, but both groups include subjects with concomitant anomalies (Table I). A sex and age matched control group of 30 children with isolated cleft palate (group 11) was randomly selected and followed up for a mean (SD) period of 3.8 (2.7) years. The patients were all examined by a paediatrician after delivery and by a pdediatrician and medical geneticist during hospital visits. It is therefore unlikely that any of them had undiagnosed Stickler syndrome (22.23). The cleft palate had been operated on at the age of 18 to 24 months in all children in both groups. The orthodontic treatment carried out for some patients during the follow up period consisted of alignment of incisors. primary molar and bicuspid extractions, and palatal expansion. No intermaxillary effecting orthodontic appliances were used. Standard lateral cephalometric radiographs were taken with the same cephalostat with a Frankfort horizontal plane. The mean ages (range) at the first and second stage examinations during the follow up period are shown in Table 11. The reference points and lines used in this study are the same as were used in our earlier study and they are shown in Fig. I . ( 3 , 18). All tracings of cephalograms were made by the first author. The angular measurements were made with a digital electronic device (TetronixR). The intraexaminer error was calculated for the first 10 patients in group I, and there were no significant differences between the first and second measurements of any variable in this study. For each variable the significance of differences between means in the groups was assessed by Studenti I test. The estimate based on unequal variances was used with the Si,cmrl J Plirsr Reronsrr H m l Surg 26
Pierre Robin syndrome (n = 35) Stage I Mean age Range Stage I1 Mean age Range Length of follow up Mean (years) Range
1 1
11
Table 11. Age (years) of the two groups when they were studied during the follow up period
MBL Fig. 1. Reference points and lines on the profile cephalometric films: ba = basion, s = sella, n = nasion, sp = spinal point, ss = subspinale. sm = supramentale. pg = pogonion, pgn = prognathion, gn = gnathion, mlp = posterior tangent point of the mandibular line. rli = the inferior tangent point of the ramus line, ar = articulare, pm= pterygomaxillare. NSL = nasion-sella line, NL = nasal line, ML = mandibular line, R L = ramus line. MBL = mandibular base line.
degrees of freedom calculated by the method of Remington and Shork, 1970 (27). The correlation matrix was calculated to assess the accuracy of the linear relationship among the variables.
Craniofacial growih in Pierre Robin syndrome and isolated cleft palate
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
RESULTS
179
the craniofacial structure constructed from the mean values at each point at each stage for both groups. Fig. 3 shows the comparison of the craniofacial structure between the groups at the two stages. Table V shows changes of the ss-n-sm angle between the two stages in the two groups. The changes were similar in the two groups. Table VI shows the correlation matrix of the cephalometric measurements at the first examination. In both groups there was an equal negative correlation between cranial base angles and the s-nsm. Similar correlations were also found between some other measured variables in both groups at both stages. The only differences between the groups were in the correlation of the s-n-ss angle to some other angles. In group I there was a significant positive correlation to the s-n-sm angle and a negative correlation to the cranial base angles; this was not the case in the control group.
In group I the mandible showed more recession among boys (ss-n-sm, NL/ML, NSL/ML), ( p < 0.05). There were no significant sex differences between the groups at either stage. Table I l l shows the comparison of the measured variables between the two groups at the two stages. At both stages there were significant differences in craniofacial structure between the groups in variables ss-n-sm, ss-n-pg, s-n-sm and s-n-pg. The differences were restricted to the position of the mandible in relation to the anterior cranial base, and to the intermaxillary relationship. The mandibles of children with Pierre Robin syndrome showed more recession than those of the control group. The relationship of the maxilla to the anterior cranial base and the cranial base angulations were similar in the two groups. In group I the angle between the palatal plane and the nasion-sella plane was more obtuse than in the control group. DISCUSSION Table IV shows the comparison of the two groups at stages I and 11; there were no significant differ- The findings reported here confirm the results of our ences in any of the variables studied. Fig. 2 shows previous cross sectional studies of children with Table I l l . Comparison of various measurements made during the two stages of study between the two groups Pierre Robin syndrome
Isolated cleft palate
~~
Variable
Stage
Mean (SD)
Mean (SD)
ss-n-sm
I II I
5.2 (2.6) 4.6 (2.5) 4.4 (2.9) 3.1 (3.0) 77.5 (4.1) 77.0 (3.3) 72.2 (4.5) 72.4 (3.9) 73.1 (4.9) 73.9 (4.5) 120.9 (4.1) 120.8 (3.8) 130.7 (4.7) 129.9 (4.4) 29.3 (6.6) 29.4 (6.4) I I .8 (4.3) 11.5(3.6) 41.1 (5.9) 40.9 (5.9) 133.7 (7.0) 130.7 (7.4)
0.0 (4.4) -0.5 (4.1) -0.1 (4.5) -1.3(4.6) 77.0 (3.2) 77.3 (3.4) 77.0 (4.4) 77.9 (4.1) 77. I (4.5) 78.6 (4.5) 122. I ( 6.4) 121.1 (6.1) 131.6 (7.2) 129.9 (7.0) 29.5 (5.5) 29.1 (7.3) 9.4 (4.5) 8.8 (4.3) 38.9 (5.7) 37.8 (6.8) 134.3(5.7) 132.2(7.3)
ss-n-pg
11
s-n-ss
I 11
s-n-sm
I 11
s-n-pg n-s-ar
I II I 11
n-s-bd NL/ML NSL/NL NSL/ML ML/RL
I I1 I II I II I I1 1
11
Difference
5.2 5. I 4.5 4.4 0.5 -3.3 -4.8 -5.5 -4.0 -4.7 - 1.2 -0.3 -0.9 0.0 -0.2 -0.3 -2.4 2.7 2.2 3.1 - 0.6 - 1.5
t
5.68 5.93 4.70 4.49 0.55 -0.37 -4.34 -5.51 - 3.43 -4.20 -0.88 -0.23 0.59 0.0 -0. I3 -0.18 -2.19 2.72 1.53 I .95 -0.38 -0.82
P value
CEPHALOMETRIC MEASUREMENTS I N PATIENTS WITH PIERRE ROBIN SYNDROME A N D ISOLATED CLEFT PALATE
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
Sirpa H. Laitinen' and Reijo E. Rants'.* From the Department of ' Pedodontics und Orthodontics, University of Helsinki and the Department of 2Plustic Surgery, Cleft Center, Helsinki University Centrul Hospital, Finland (Submitted for publication March 27, 1991)
Abstract. To compare craniofacial structure and growth, two standard lateral cephalograms of 35 children with Pierre Robin syndrome and 30 age and sex matched children with isolated cleft palate were taken at two different ages. The mean (SD) age of the children with Pierre Robin syndrome was 9.5 (3.0) years and of the children with isolated cleft palate 7.1 ( I. 1 ) years at the start of the follow up period. The follow up time in the first group was 4.3 (1.6) and in the second group 3.8 (2.7) years. There were no significant differences between the groups in the shape of the cranial base or the maxilla. The main differences were in the mandible, which showed more recession among those with Pierre Robin syndrome. There was a significant correlation between the shape of the maxilla and that of the mandible in that group, but not in the group with isolated cleft palate. During the follow up period there were no significant differences between the two groups in the rate of growth of the jaws. The association between the maxilla and the mandible (ss-n-sm) remained unchanged, or increased, or decreased with equal frequency in both groups. There was no catch up mandibular growth among the children with Pierre Robin syndrome. Ke,v tvords: Pierre Robin syndrome, isolated cleft palate, craniofacial growth, craniofacial morphology.
The Pierre Robin syndrome refers to a combination of micrognathia, glossoptosis, and cleft palate, which may occur as an isolated defect or as part of a broader pattern of malformations (4-6,9). The aetiology is complex (5), and it has been suggested that it may be a non specific symptom complex rather than a specific syndrome (4). The growth pattern of children with Pierre Robin syndrome varies depending on the aetiology. In the newborn period it clearly differs from the isolated cleft palate with regard to the maxillary overjet, but not to the width of the cleft ( 1 I ) ; the mandible is the structure that varies (18,21). Moreover, many authors accept that substantial spontaneous correction
in the facial profile will occur within the first few years of life ( 11, 13- 15, 17, 25). Marcovic ( 13) showed that the normalisation in the relationship of the jaws occurred after the age of 10 years, and a retrognathic maxilla was a common finding in his study of 15 children with Pierre Robin syndrome. Randall et al. (17) showed three well defined growth patterns in 18 1 year old children with the syndrome: almost normal mandibular size and position; persistent micrognathia; and a tendency to forward protrusion and achievement of a fairly normal anterior relationship. Closer examination of the mandible in such patients shows the pathognomic shape and proportion. The gonial angle is obtuse, the condyle extends distally from the ramus, and the ramus to body proportion deviates because of the reduction in the body length (16.25). The features can be retained from infancy into later years, but disappear with age ( I I , 13, 15- 17,25). The slope of both maxilla and mandible of Pierre Robin syndrome is anteriorly downwards, and the gonial angle is more obtuse than in patients with isolated cleft palate (18). The cranial base angle in patients with Pierre Robin syndrome is nearly the same or larger than that in patients with isolated cleft palate ( 1 I), in whom it either does not differ from the mean among subjects without clefts (2, 7, 18), or may show greater flexion of the angle ( 12). The aim of this follow up study was to compare the craniofacial structure and growth in children with the Pierre Robin syndrome with that among children with isolated cleft palate. PATIENTS AND METHODS We studied 35 patients with Pierre Robin syndrome (group I); there were 17 boys and 18 girls aged from 4-20 Scund
J Plus: Reconsrr Hund Surg 26
178
S. H . Luitinen and R. E. Ranta
Table I. Other congenital anomalies in the two groups
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
Pierre Robin syndrome ( n = 35) Hypertelorism Myopia Heart murmur Talipes Mandibular tumor Protruding ears Central depression of lower lip Van der WoudeS syndrome Hypoplastic nose Uveal coloboma Other Total
Isolated cleft palate (n = 30)
2 0 0 0
0
Isolated cleft palate (11 = 30)
9. I 4.1-16.0
7. I 5.0- 16.4
13.3 7.6-20.0
12.4 7.4-21.8
4.3 1 . 1 -7.0
3.8 1.0- 12.7
9
years. The mean (SD)follow up period was 4.3 ( I .6) years. The diagnostic criteria were micrognathia, cleft palate, and various degrees of respiratory difficulties caused by glossoptosis in the immediate neonatal period. Other distinct syndromes were not included in this group or in the control group, but both groups include subjects with concomitant anomalies (Table I). A sex and age matched control group of 30 children with isolated cleft palate (group 11) was randomly selected and followed up for a mean (SD) period of 3.8 (2.7) years. The patients were all examined by a paediatrician after delivery and by a pdediatrician and medical geneticist during hospital visits. It is therefore unlikely that any of them had undiagnosed Stickler syndrome (22.23). The cleft palate had been operated on at the age of 18 to 24 months in all children in both groups. The orthodontic treatment carried out for some patients during the follow up period consisted of alignment of incisors. primary molar and bicuspid extractions, and palatal expansion. No intermaxillary effecting orthodontic appliances were used. Standard lateral cephalometric radiographs were taken with the same cephalostat with a Frankfort horizontal plane. The mean ages (range) at the first and second stage examinations during the follow up period are shown in Table 11. The reference points and lines used in this study are the same as were used in our earlier study and they are shown in Fig. I . ( 3 , 18). All tracings of cephalograms were made by the first author. The angular measurements were made with a digital electronic device (TetronixR). The intraexaminer error was calculated for the first 10 patients in group I, and there were no significant differences between the first and second measurements of any variable in this study. For each variable the significance of differences between means in the groups was assessed by Studenti I test. The estimate based on unequal variances was used with the Si,cmrl J Plirsr Reronsrr H m l Surg 26
Pierre Robin syndrome (n = 35) Stage I Mean age Range Stage I1 Mean age Range Length of follow up Mean (years) Range
1 1
11
Table 11. Age (years) of the two groups when they were studied during the follow up period
MBL Fig. 1. Reference points and lines on the profile cephalometric films: ba = basion, s = sella, n = nasion, sp = spinal point, ss = subspinale. sm = supramentale. pg = pogonion, pgn = prognathion, gn = gnathion, mlp = posterior tangent point of the mandibular line. rli = the inferior tangent point of the ramus line, ar = articulare, pm= pterygomaxillare. NSL = nasion-sella line, NL = nasal line, ML = mandibular line, R L = ramus line. MBL = mandibular base line.
degrees of freedom calculated by the method of Remington and Shork, 1970 (27). The correlation matrix was calculated to assess the accuracy of the linear relationship among the variables.
Craniofacial growih in Pierre Robin syndrome and isolated cleft palate
Scand J Plast Surg Recontr Surg Hand Surg Downloaded from informahealthcare.com by RMIT University on 08/15/15 For personal use only.
RESULTS
179
the craniofacial structure constructed from the mean values at each point at each stage for both groups. Fig. 3 shows the comparison of the craniofacial structure between the groups at the two stages. Table V shows changes of the ss-n-sm angle between the two stages in the two groups. The changes were similar in the two groups. Table VI shows the correlation matrix of the cephalometric measurements at the first examination. In both groups there was an equal negative correlation between cranial base angles and the s-nsm. Similar correlations were also found between some other measured variables in both groups at both stages. The only differences between the groups were in the correlation of the s-n-ss angle to some other angles. In group I there was a significant positive correlation to the s-n-sm angle and a negative correlation to the cranial base angles; this was not the case in the control group.
In group I the mandible showed more recession among boys (ss-n-sm, NL/ML, NSL/ML), ( p < 0.05). There were no significant sex differences between the groups at either stage. Table I l l shows the comparison of the measured variables between the two groups at the two stages. At both stages there were significant differences in craniofacial structure between the groups in variables ss-n-sm, ss-n-pg, s-n-sm and s-n-pg. The differences were restricted to the position of the mandible in relation to the anterior cranial base, and to the intermaxillary relationship. The mandibles of children with Pierre Robin syndrome showed more recession than those of the control group. The relationship of the maxilla to the anterior cranial base and the cranial base angulations were similar in the two groups. In group I the angle between the palatal plane and the nasion-sella plane was more obtuse than in the control group. DISCUSSION Table IV shows the comparison of the two groups at stages I and 11; there were no significant differ- The findings reported here confirm the results of our ences in any of the variables studied. Fig. 2 shows previous cross sectional studies of children with Table I l l . Comparison of various measurements made during the two stages of study between the two groups Pierre Robin syndrome
Isolated cleft palate
~~
Variable
Stage
Mean (SD)
Mean (SD)
ss-n-sm
I II I
5.2 (2.6) 4.6 (2.5) 4.4 (2.9) 3.1 (3.0) 77.5 (4.1) 77.0 (3.3) 72.2 (4.5) 72.4 (3.9) 73.1 (4.9) 73.9 (4.5) 120.9 (4.1) 120.8 (3.8) 130.7 (4.7) 129.9 (4.4) 29.3 (6.6) 29.4 (6.4) I I .8 (4.3) 11.5(3.6) 41.1 (5.9) 40.9 (5.9) 133.7 (7.0) 130.7 (7.4)
0.0 (4.4) -0.5 (4.1) -0.1 (4.5) -1.3(4.6) 77.0 (3.2) 77.3 (3.4) 77.0 (4.4) 77.9 (4.1) 77. I (4.5) 78.6 (4.5) 122. I ( 6.4) 121.1 (6.1) 131.6 (7.2) 129.9 (7.0) 29.5 (5.5) 29.1 (7.3) 9.4 (4.5) 8.8 (4.3) 38.9 (5.7) 37.8 (6.8) 134.3(5.7) 132.2(7.3)
ss-n-pg
11
s-n-ss
I 11
s-n-sm
I 11
s-n-pg n-s-ar
I II I 11
n-s-bd NL/ML NSL/NL NSL/ML ML/RL
I I1 I II I II I I1 1
11
Difference
5.2 5. I 4.5 4.4 0.5 -3.3 -4.8 -5.5 -4.0 -4.7 - 1.2 -0.3 -0.9 0.0 -0.2 -0.3 -2.4 2.7 2.2 3.1 - 0.6 - 1.5
t
5.68 5.93 4.70 4.49 0.55 -0.37 -4.34 -5.51 - 3.43 -4.20 -0.88 -0.23 0.59 0.0 -0. I3 -0.18 -2.19 2.72 1.53 I .95 -0.38 -0.82
P value
