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Cartilaginous septum deviation in children with cleft lip, alveolus and palate – an MRI analysis
Journal of Cranio-Maxillofacial Surgery (2006), 34, Suppl. S2, 49–51 © 2006 European Association for Cranio-Maxillofacial Surgery available online at http://www.sciencedirect.com
Cartilaginous septum deviation in children with cleft lip, alveolus and palate – an MRI analysis Thomas BAYERLEIN 1 , Peter PROFF 1 , Thomas KOPPE 2 , Jochen FANGHAENEL 1 , Norbert HOSTEN 3 1
Department of Orthodontics, Preventive and Pediatric Dentistry (Head: Prof. Dr. T. Gedrange) Department of Anatomy and Cell Biology (Head: Prof. Dr. K. Endlich) 3 Department of Diagnostic Radiology and Neuroradiology (Head: Prof. Dr. N. Hosten), Ernst Moritz Arndt University Greifswald, Germany 2
SUMMARY. Introduction: This study aimed to investigate by MRI examination the degree of deviation of the cartilaginous septum in relation to cleft size in patients with cleft lip, alveolus and palate. Material and methods: Six children with cleft lip, alveolus and palate at age 5–20 days were examined with a 1.0 Tesla scanner using a head coil. The following parameters were evaluated: maximal cleft size (millimeter) and degree of the nasal septum deviation from the median-sagittal plane (degrees). Results: Two children with bilateral clefts had no deviation; 3 children with unilateral (left-sided) cleft had a deviation to the right and 1 patient with a unilateral right-sided cleft a deviation to the left side. In all 4 patients, the degree of the nasal septum deviation increased with cleft size. Conclusion: Cartilaginous nasal septum deviation was noticed only in patients with unilateral cleft lip and palate toward the non-cleft side and was greater with increasing cleft sizes. © 2006 European Association for Cranio-Maxillofacial Surgery Keywords: nasal septum deformity; cleft lip and palate; MRI analysis
INTRODUCTION
it (Suzuki et al., 1999; Warren et al., 1969/1989). This study aimed to evaluate the direction of deviation of the cartilaginous nasal septum as well as its degree in relation to cleft width by MRI examination of children with clefts of lip, alveolus and palate.
Clefts of lip, alveolus and palate are among the most important and most frequent craniofacial anomalies with a steadily increasing incidence – meanwhile amounting to 1:500 births in central Europe (Koch et al., 1995). They develop during early embryonic organogenesis between the 4th and 12th gestational week due to an interplay of endogenous and exogenous factors. From an aetiological point of view, the previously favoured model of “multifactorial polygenic inheritance with threshold effect” is no longer regarded as up-to-date considering the disease’s complexity. Besides different gender and side specific distributions of the clefts (Derijcke et al., 1996; Shapira et al., 1999), these patients show a number of heterogeneous anatomical variations and audiological and rhinological disorders of function (Suzuki et al., 1999). With respect to nasal sinus morphology, numerous clinical and radiological studies have provided evidence of an increased incidence of nasal septum deviations in children with unilateral cleft lip and palate as compared to the normal population (Aduss and Pruzansky, 1967; Drettner, 1960; Sandham and Murray, 1993). Nasal septum deviation as a cleft-associated factor may favour pathological mouth breathing resulting from increased nasal airway resistance, which not only implies negative consequences to the respiratory tract, but may subsequently also aggravate existing malocclusion or increase the incidence of
PATIENTS AND METHODS This study included MRI diagnostics of the skull in 6 newborn cleft patients (4 males, 2 females, with a total of 2 bilateral, 3 left-sided, and 1 right-sided cleft lip and palate) at 5–20 days of age (10.9 ± 5.2 days; Table 1). The MRI examination was performed using a 1.0 Tesla device (Magnetom Impact Expert, Siemens, Erlangen) with a head coil. A T1-weighted spin-echo sequence with the following parameters was chosen for examination: pulse repetition time (TR) 570 ms, echo time (TE) 14 ms, field of view (fov) 173 × 230 mm, matrix Table 1 – Gender distribution of cleft lip, alveolus and palate (CLAP) types within the study sample
Number of CLAP Left-sided CLAP Right-sided CLAP Bilateral CLAP
49
Male
Female
Total
4 1 1 2
2 2 -
6 3 1 2
50
Journal of Cranio-Maxillofacial Surgery
192 × 2560 pixel, gapless slice thickness 3 mm. The enlargement factor was calculated by preceding MRI examination of an individually manufactured specimen (square of 1 cm side length, consisting of a 0.16 inch nickel-titanium wire, embedded in plastic) with subsequent measurement using the tomographic image. The factor was 1/2.33. The newborns were sedated using chlorale hydrate (1.5ml/kg body weight). MRI examination was performed in supine position. The head was placed in the centre of the magnetic field and fixed with laterally attached towels. The radiation path was parallel of the nasion-menton line in all children examined. Measurement of cleft width and assessment of septal deviation were done using these coronal tomograms. The data were transmitted to a separate workstation (Indy, Silicon Graphics, Mountain View, USA). Planes that permitted recognition of the maximal diameter of the cleft alveolus or palate were chosen for slice orientation. Measurements (mm) were made taking into consideration the magnification factor. The direction of septal deviation was determined and the degree was given in degrees with reference to the midsagittal plane. RESULTS The deviation of the cartilaginous nasal septum from the median-sagittal plane was 11.6 ± 7.3° (n = 6). The direction of the nasal septum deviation depended on the side of the cleft: The cartilaginous nasal septum deviated towards the non-cleft side, while no deviation was observed in bilateral clefts (Tables 2 and 3). The greater the deviation of the cartilaginous nasal septum the greater the cleft width giving evidence of a well known correlation. The smallest deviation (amounting to 5°) was observed in a cleft of 7 mm width, whereas the maximum deviation of 22° was found in the child displaying the widest cleft within the study sample amounting to 16.4 mm (alveolus) and 8.6 mm (palate) (Tables 2 and 3). Table 2 – Left- (n = 3) and right-sided CLAP (n = 1) Size of alveolar cleft
Size of cleft palate
Side of cleft
Degree of cartilaginous septum deviation
7 mm 9.5 mm 12.8 mm 16.4 mm
7 mm 7.5 mm 8.6 mm 8.6 mm
L L L R
5° to the right 9° to the right 10.5° to the right 22° to the left
Table 3 – Bilateral CLAP (n =2) Size of alveolar cleft
Size of cleft palate
Degree of cartilaginous septum deviation
4.7 mm left L 5.8 mm right R 7.2 mm L 6 mm R
5.2 mm L 4.4 mm R 6 mm to the L 5.5 mm to the R
0° 0°
DISCUSSION A disturbed structure of the naso-maxillary complex is a common concomitant in children with unilateral clefts of lip, alveolus and palate. These anatomical variations have been examined by numerous radiographic studies already (Harvold et al.1954; Mølsted and Dahl, 1990). From a rhinological point of view, the nasal septum deviation rises the nasal airway resistance on the affected side and poses a crucial problem. Combined with pathologically forced mouth breathing it may, besides a number of general dental and orthodontic secondary disorders, lead not only to an increase of rhinological diseases such as upper airway infections, sinusitis or sleep apnea syndrome, but also to internal medical diseases like hypertension or cardiac arrhythmia (Josephson et al. 1996; Ishikawa et al., 1989). The patients with unilateral cleft lip, alveolus and palate examined within this study displayed an association between the direction of nasal septum deviation and cleft width, with the dislocation of the cartilaginous nasal septum being directed exclusively to the non-cleft side. This finding is supporting the findings of several authors in previous studies. Aduss and Pruzansky (1967) described the deviation of the cartilaginous nasal septum toward the healthy side by means of posterioranterior radiographs. Similar results were obtained by Li et al. (2000) who studied 6 stillborn children with complete unilateral clefts of lip, alveolus and palate. Sandham and Murray (1993) reported deviation of the cartilaginous nasal septum toward the non-cleft side in 18 out of their 21 patients with unilateral clefts. A convex displacement of the nasal septum toward the cleft side was described by Suzuki et al. (1999). Apart from deviation of the cartilaginous nasal septum – which has been in the focus of the current study – numerous other publications also pay attention to displacement of the bony nasal septum which significantly deviates toward the cleft side (Drettner, 1960; Sandham and Murray, 1993; Mølsted and Dahl, 1990). No comparable studies can be found in current literature regarding the degree of deviation of the cartilaginous nasal septum which was found to increase with cleft width. The negative consequences of an increasing deviation of the cartilaginous nasal septum for airway resistance and, thus, for airflow patency of the nasal cavity on the non-cleft side is rated as a minor pathological-functional event compared to the deviation of the bony nasal septum to the cleft side (Dretter, 1960; Sandham and Murray, 1993). Due to the severity of resulting negative effects on the organism, higher significance may be ascribed to intercorrelations between the cleft width and the degree of deviation of the bony nasal septum, which makes necessary further studies involving larger samples. For surgical therapy of septal deviation in cleft children, however, the degree of both the bony and the cartilaginous deviation play a role, as distinctive types of septum deformation do not lend themselves to classical septoplastic techniques, but require correction using the more invasive technique of extracorporal septoplasty (Gubisch, 2002) later in life.
Cartilaginous septum deviation in children with cleft lip, alveolus and palate – an MRI analysis
CONCLUSION Unilateral cleft lip, alveolus and palate is closely associated with craniofacial deformations which develop with increasing severity of the underlying disease. In this study, MRI examination of the deviation of the cartilaginous nasal septum revealed a deviation to the non-cleft side increasing with cleft width. Literature provides evidence, however, that deformation of the bony nasal septum seems to be of far greater importance acting as a co-factor of possible secondary cleft-associated diseases. Hence, further studies on the intercorrelations of these structures may be in the focus of interest. References Aduss H, Pruzansky S: The nasal cavity in complete unilateral cleft lip and palate. Arch Otolaryngol 85: 75–83, 1967 Derijcke A, Eerens A, Carels C: The incidence of oral clefts: a review. Br J Oral Maxillofac Surg 34: 488, 1996 Drettner B: The nasal airway and hearing in patients with cleft palate. Acta Otolaryngol (Stockh) 54: 131–140, 1960 Gubisch W: Zwanzig Jahre Erfahrung mit der extrakorporalen Septumkorrektur. Laryngorhinootologie 81: 22–30, 2002 Harvold E: Cleft lip and palate. Am J Orthod 40: 493–450, 1954 Ishikawa Y, Kawano M, Honjo I, Amitani R: The cause of nasal sinusitis in patients with cleft palate. Arch Otolaryngol Head Neck Surg 115: 442–446, 1989. Josephson GD, Levine J, Cutting CB: Septoplasty for obstructive sleep apnea in infants after cleft lip repair. Cleft Palate Craniofac J 33: 473–476, 1996 Jörgensen G: Ätiologie der Lippen-Kiefer-Gaumenspalte. Med Zeitschr 10: 293, 1969
51
Koch H, Grzonka M, Koch J: Cleft malformation of lip, alveolus, hard and soft palate and nose (LAHSN)- a critical view of the terminology, the diagnosis and gradation as a basis for documentation and therapy. British J Oral Max Surg 33: 51–58, 1995 Li AQ, Sun YG, Wang GH, Zhong ZK, Cutting C: Anatomy of the nasal cartilages of the unilateral cleft lip nose. Plastic and reconstructive surgery 109: 1835–1838, 2002 Mølsted K, Dahl E: Asymmetry of the maxilla in children with complete unilateral cleft lip and palate. Cleft Palate Craniofac J 27: 184–190, 1990 Sandham A, Murray JA: Nasal septal deformity in unilateral cleft lip and palate. Cleft Palate Craniofac J 30: 222–226, 1993 Shapira Y, Lubit E, Kuftinec MM et al: The distribution of clefts of the primary and secondary palates by sex, type, and locations. Angle Orthod 69: 523, 1999 Suzuki H, Yamaguchi T, Furukawa M: Rhinologic computed tomographic evaluation in patients with cleft lip and palate. Arch Otolaryngol Head Neck Surg 125: 1000–1004, 1999 Warren DW, Duany LF, Fisher WD: Nasal pathway resistance in normal and cleft lip and Palate subjects 6: 134–140, 1969 Warren DW, Hairfield WM, Dalston ET, Sidman JD, Pillsbury HC: Effects of cleft lip and palate on the nasal airway in children. Arch Otolaryngol Head Neck Surg 115: 750–751, 1989 Dr. Dr. Thomas BAYERLEIN Poliklinik für Kieferorthopädie, Präventive und Kinderzahnheilkunde Zentrum für Zahn-, Mund- und Kieferheilkunde Ernst-Moritz-Arndt-Universität Greifswald Rotgerberstraße 8 D-17487 Greifswald Germany Tel.: +0 (49) 3834 / 86-7110 Fax: +0 (49) 3834 / 86-7113 E-mail: kieferorthopä[email protected]
Cartilaginous septum deviation in children with cleft lip, alveolus and palate – an MRI analysis Thomas BAYERLEIN 1 , Peter PROFF 1 , Thomas KOPPE 2 , Jochen FANGHAENEL 1 , Norbert HOSTEN 3 1
Department of Orthodontics, Preventive and Pediatric Dentistry (Head: Prof. Dr. T. Gedrange) Department of Anatomy and Cell Biology (Head: Prof. Dr. K. Endlich) 3 Department of Diagnostic Radiology and Neuroradiology (Head: Prof. Dr. N. Hosten), Ernst Moritz Arndt University Greifswald, Germany 2
SUMMARY. Introduction: This study aimed to investigate by MRI examination the degree of deviation of the cartilaginous septum in relation to cleft size in patients with cleft lip, alveolus and palate. Material and methods: Six children with cleft lip, alveolus and palate at age 5–20 days were examined with a 1.0 Tesla scanner using a head coil. The following parameters were evaluated: maximal cleft size (millimeter) and degree of the nasal septum deviation from the median-sagittal plane (degrees). Results: Two children with bilateral clefts had no deviation; 3 children with unilateral (left-sided) cleft had a deviation to the right and 1 patient with a unilateral right-sided cleft a deviation to the left side. In all 4 patients, the degree of the nasal septum deviation increased with cleft size. Conclusion: Cartilaginous nasal septum deviation was noticed only in patients with unilateral cleft lip and palate toward the non-cleft side and was greater with increasing cleft sizes. © 2006 European Association for Cranio-Maxillofacial Surgery Keywords: nasal septum deformity; cleft lip and palate; MRI analysis
INTRODUCTION
it (Suzuki et al., 1999; Warren et al., 1969/1989). This study aimed to evaluate the direction of deviation of the cartilaginous nasal septum as well as its degree in relation to cleft width by MRI examination of children with clefts of lip, alveolus and palate.
Clefts of lip, alveolus and palate are among the most important and most frequent craniofacial anomalies with a steadily increasing incidence – meanwhile amounting to 1:500 births in central Europe (Koch et al., 1995). They develop during early embryonic organogenesis between the 4th and 12th gestational week due to an interplay of endogenous and exogenous factors. From an aetiological point of view, the previously favoured model of “multifactorial polygenic inheritance with threshold effect” is no longer regarded as up-to-date considering the disease’s complexity. Besides different gender and side specific distributions of the clefts (Derijcke et al., 1996; Shapira et al., 1999), these patients show a number of heterogeneous anatomical variations and audiological and rhinological disorders of function (Suzuki et al., 1999). With respect to nasal sinus morphology, numerous clinical and radiological studies have provided evidence of an increased incidence of nasal septum deviations in children with unilateral cleft lip and palate as compared to the normal population (Aduss and Pruzansky, 1967; Drettner, 1960; Sandham and Murray, 1993). Nasal septum deviation as a cleft-associated factor may favour pathological mouth breathing resulting from increased nasal airway resistance, which not only implies negative consequences to the respiratory tract, but may subsequently also aggravate existing malocclusion or increase the incidence of
PATIENTS AND METHODS This study included MRI diagnostics of the skull in 6 newborn cleft patients (4 males, 2 females, with a total of 2 bilateral, 3 left-sided, and 1 right-sided cleft lip and palate) at 5–20 days of age (10.9 ± 5.2 days; Table 1). The MRI examination was performed using a 1.0 Tesla device (Magnetom Impact Expert, Siemens, Erlangen) with a head coil. A T1-weighted spin-echo sequence with the following parameters was chosen for examination: pulse repetition time (TR) 570 ms, echo time (TE) 14 ms, field of view (fov) 173 × 230 mm, matrix Table 1 – Gender distribution of cleft lip, alveolus and palate (CLAP) types within the study sample
Number of CLAP Left-sided CLAP Right-sided CLAP Bilateral CLAP
49
Male
Female
Total
4 1 1 2
2 2 -
6 3 1 2
50
Journal of Cranio-Maxillofacial Surgery
192 × 2560 pixel, gapless slice thickness 3 mm. The enlargement factor was calculated by preceding MRI examination of an individually manufactured specimen (square of 1 cm side length, consisting of a 0.16 inch nickel-titanium wire, embedded in plastic) with subsequent measurement using the tomographic image. The factor was 1/2.33. The newborns were sedated using chlorale hydrate (1.5ml/kg body weight). MRI examination was performed in supine position. The head was placed in the centre of the magnetic field and fixed with laterally attached towels. The radiation path was parallel of the nasion-menton line in all children examined. Measurement of cleft width and assessment of septal deviation were done using these coronal tomograms. The data were transmitted to a separate workstation (Indy, Silicon Graphics, Mountain View, USA). Planes that permitted recognition of the maximal diameter of the cleft alveolus or palate were chosen for slice orientation. Measurements (mm) were made taking into consideration the magnification factor. The direction of septal deviation was determined and the degree was given in degrees with reference to the midsagittal plane. RESULTS The deviation of the cartilaginous nasal septum from the median-sagittal plane was 11.6 ± 7.3° (n = 6). The direction of the nasal septum deviation depended on the side of the cleft: The cartilaginous nasal septum deviated towards the non-cleft side, while no deviation was observed in bilateral clefts (Tables 2 and 3). The greater the deviation of the cartilaginous nasal septum the greater the cleft width giving evidence of a well known correlation. The smallest deviation (amounting to 5°) was observed in a cleft of 7 mm width, whereas the maximum deviation of 22° was found in the child displaying the widest cleft within the study sample amounting to 16.4 mm (alveolus) and 8.6 mm (palate) (Tables 2 and 3). Table 2 – Left- (n = 3) and right-sided CLAP (n = 1) Size of alveolar cleft
Size of cleft palate
Side of cleft
Degree of cartilaginous septum deviation
7 mm 9.5 mm 12.8 mm 16.4 mm
7 mm 7.5 mm 8.6 mm 8.6 mm
L L L R
5° to the right 9° to the right 10.5° to the right 22° to the left
Table 3 – Bilateral CLAP (n =2) Size of alveolar cleft
Size of cleft palate
Degree of cartilaginous septum deviation
4.7 mm left L 5.8 mm right R 7.2 mm L 6 mm R
5.2 mm L 4.4 mm R 6 mm to the L 5.5 mm to the R
0° 0°
DISCUSSION A disturbed structure of the naso-maxillary complex is a common concomitant in children with unilateral clefts of lip, alveolus and palate. These anatomical variations have been examined by numerous radiographic studies already (Harvold et al.1954; Mølsted and Dahl, 1990). From a rhinological point of view, the nasal septum deviation rises the nasal airway resistance on the affected side and poses a crucial problem. Combined with pathologically forced mouth breathing it may, besides a number of general dental and orthodontic secondary disorders, lead not only to an increase of rhinological diseases such as upper airway infections, sinusitis or sleep apnea syndrome, but also to internal medical diseases like hypertension or cardiac arrhythmia (Josephson et al. 1996; Ishikawa et al., 1989). The patients with unilateral cleft lip, alveolus and palate examined within this study displayed an association between the direction of nasal septum deviation and cleft width, with the dislocation of the cartilaginous nasal septum being directed exclusively to the non-cleft side. This finding is supporting the findings of several authors in previous studies. Aduss and Pruzansky (1967) described the deviation of the cartilaginous nasal septum toward the healthy side by means of posterioranterior radiographs. Similar results were obtained by Li et al. (2000) who studied 6 stillborn children with complete unilateral clefts of lip, alveolus and palate. Sandham and Murray (1993) reported deviation of the cartilaginous nasal septum toward the non-cleft side in 18 out of their 21 patients with unilateral clefts. A convex displacement of the nasal septum toward the cleft side was described by Suzuki et al. (1999). Apart from deviation of the cartilaginous nasal septum – which has been in the focus of the current study – numerous other publications also pay attention to displacement of the bony nasal septum which significantly deviates toward the cleft side (Drettner, 1960; Sandham and Murray, 1993; Mølsted and Dahl, 1990). No comparable studies can be found in current literature regarding the degree of deviation of the cartilaginous nasal septum which was found to increase with cleft width. The negative consequences of an increasing deviation of the cartilaginous nasal septum for airway resistance and, thus, for airflow patency of the nasal cavity on the non-cleft side is rated as a minor pathological-functional event compared to the deviation of the bony nasal septum to the cleft side (Dretter, 1960; Sandham and Murray, 1993). Due to the severity of resulting negative effects on the organism, higher significance may be ascribed to intercorrelations between the cleft width and the degree of deviation of the bony nasal septum, which makes necessary further studies involving larger samples. For surgical therapy of septal deviation in cleft children, however, the degree of both the bony and the cartilaginous deviation play a role, as distinctive types of septum deformation do not lend themselves to classical septoplastic techniques, but require correction using the more invasive technique of extracorporal septoplasty (Gubisch, 2002) later in life.
Cartilaginous septum deviation in children with cleft lip, alveolus and palate – an MRI analysis
CONCLUSION Unilateral cleft lip, alveolus and palate is closely associated with craniofacial deformations which develop with increasing severity of the underlying disease. In this study, MRI examination of the deviation of the cartilaginous nasal septum revealed a deviation to the non-cleft side increasing with cleft width. Literature provides evidence, however, that deformation of the bony nasal septum seems to be of far greater importance acting as a co-factor of possible secondary cleft-associated diseases. Hence, further studies on the intercorrelations of these structures may be in the focus of interest. References Aduss H, Pruzansky S: The nasal cavity in complete unilateral cleft lip and palate. Arch Otolaryngol 85: 75–83, 1967 Derijcke A, Eerens A, Carels C: The incidence of oral clefts: a review. Br J Oral Maxillofac Surg 34: 488, 1996 Drettner B: The nasal airway and hearing in patients with cleft palate. Acta Otolaryngol (Stockh) 54: 131–140, 1960 Gubisch W: Zwanzig Jahre Erfahrung mit der extrakorporalen Septumkorrektur. Laryngorhinootologie 81: 22–30, 2002 Harvold E: Cleft lip and palate. Am J Orthod 40: 493–450, 1954 Ishikawa Y, Kawano M, Honjo I, Amitani R: The cause of nasal sinusitis in patients with cleft palate. Arch Otolaryngol Head Neck Surg 115: 442–446, 1989. Josephson GD, Levine J, Cutting CB: Septoplasty for obstructive sleep apnea in infants after cleft lip repair. Cleft Palate Craniofac J 33: 473–476, 1996 Jörgensen G: Ätiologie der Lippen-Kiefer-Gaumenspalte. Med Zeitschr 10: 293, 1969
51
Koch H, Grzonka M, Koch J: Cleft malformation of lip, alveolus, hard and soft palate and nose (LAHSN)- a critical view of the terminology, the diagnosis and gradation as a basis for documentation and therapy. British J Oral Max Surg 33: 51–58, 1995 Li AQ, Sun YG, Wang GH, Zhong ZK, Cutting C: Anatomy of the nasal cartilages of the unilateral cleft lip nose. Plastic and reconstructive surgery 109: 1835–1838, 2002 Mølsted K, Dahl E: Asymmetry of the maxilla in children with complete unilateral cleft lip and palate. Cleft Palate Craniofac J 27: 184–190, 1990 Sandham A, Murray JA: Nasal septal deformity in unilateral cleft lip and palate. Cleft Palate Craniofac J 30: 222–226, 1993 Shapira Y, Lubit E, Kuftinec MM et al: The distribution of clefts of the primary and secondary palates by sex, type, and locations. Angle Orthod 69: 523, 1999 Suzuki H, Yamaguchi T, Furukawa M: Rhinologic computed tomographic evaluation in patients with cleft lip and palate. Arch Otolaryngol Head Neck Surg 125: 1000–1004, 1999 Warren DW, Duany LF, Fisher WD: Nasal pathway resistance in normal and cleft lip and Palate subjects 6: 134–140, 1969 Warren DW, Hairfield WM, Dalston ET, Sidman JD, Pillsbury HC: Effects of cleft lip and palate on the nasal airway in children. Arch Otolaryngol Head Neck Surg 115: 750–751, 1989 Dr. Dr. Thomas BAYERLEIN Poliklinik für Kieferorthopädie, Präventive und Kinderzahnheilkunde Zentrum für Zahn-, Mund- und Kieferheilkunde Ernst-Moritz-Arndt-Universität Greifswald Rotgerberstraße 8 D-17487 Greifswald Germany Tel.: +0 (49) 3834 / 86-7110 Fax: +0 (49) 3834 / 86-7113 E-mail: kieferorthopä[email protected]