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Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Oral strength in subjects with a unilateral cleft lip and palate Kristiane M. Van Lierde a, *, Kim Bettens a , Anke Luyten a , Janne Plettinck a , Katrien Bonte b , Hubert Vermeersch b , Nathalie Roche c a
Department of Speech, Language and Hearing Sciences, Ghent University, Belgium Department of Head and Neck Surgery, Ghent University Hospital, Belgium c Department of Plastic Surgery, Ghent University Hospital, Belgium b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 24 February 2014 Received in revised form 9 May 2014 Accepted 13 May 2014 Available online xxx
Purpose: Facial appearance and speech outcome may affect psychosocial functioning in girls and boys. Several studies reported dissatisfaction with facial appearance and more specifically the lip and mouth profile in children with cleft lip and palate (CLP). The purpose of this controlled study was to measure the tongue and lip strength and endurance in boys and girls with CLP. Methods: Twenty-five subjects (mean age: 10.6 years) with a unilateral CLP and a gender- and agematched control group were selected. All subjects with an unilateral CLP consulted the same craniofacial team and had undergone an identical surgical procedure. Surgical procedure of the lip was performed using a modified Millard technique without primary nose correction at an average age of 5.5 months. The Iowa Oral Performance instrument was used to measure lip and tongue strength and tongue endurance. Results: The results of the Iowa Oral Performance measurement showed no significant differences between the subjects with an unilateral cleft lip and palate and the age and gender matched control group without a cleft lip and palate. Conclusion: There is no significant differences regarding oral strength more specifically the lip and tongue strength and endurance between subjects with and without an unilateral cleft lip and palate. ENT specialists and speech pathologists must be aware of this aspect of the normal lip and tongue functions. ã 2014 Elsevier Ireland Ltd. All rights reserved.
Keywords: Cleft lip and palate Iowa Oral Performance Instrument Lip strength Tongue strength Tongue endurance
Introduction Facial appearance and speech outcome may affect psychosocial functioning [1] in girls and boys. Several studies reported dissatisfaction with facial appearance [1–4] and more specifically the lip and mouth profile [5–10] in children with cleft lip and palate. An appropriate lip and also tongue function is essential for facial aesthetics (e.g., lip competence, interdental tongue behavior), speech production and non-verbal functions like chewing, swallowing and facial emotional readability. Few authors assessed oral strength in children with cleft lip and palate. Table 1 provides a summary of recent studies regarding lip strength in children with cleft lip and palate. Several studies reported restrictions and/or compensatory behavior in upper lip or nasolabial movements [11–15] and one study [11] mentioned variable interlip coupling. Some of these studies were performed in specific controlled test situations with
* Corresponding author at: Department of Speech, Language and Hearing Sciences, Ghent University Hospital, ENT 2P1, De Pintelaan 185, 9000, Gent, Belgium. Tel.: +09 332 23 32 . E-mail address: [email protected] (K.M. Van Lierde).
for example the use of a midsagittal articulograph [11] or the use of an instrument with an interdental yoke and lip saddle [13]. Moreover, small control groups [11] or no age- [12,15] and gendermatched [11,12] control groups were used. Studies clearly identifying specific outcome measures in both boys and girls with clefts regarding oral strength have the power to evaluate cleft related surgical techniques (e.g., the type and timing of primary lip closure and revisions of the lip repair). The purpose of this controlled study was to measure the tongue and lip strength and endurance using the Iowa Oral Performance Instrument (IOPI) [17] in boys and girls with unilateral cleft lip and palate (CLP). Assessment of the lip function is necessary to evaluate the surgical procedure of the lip. All patients were treated by the craniofacial team of the Ghent University Hospital. Based on the results of previous reports in the literature, a decreased lip strength was hypothesized in subjects with clefts compared with subjects without a cleft. Methods and materials This study was approved by the Human Subject Committee of the Ghent University (B670201215561).
http://dx.doi.org/10.1016/j.ijporl.2014.05.017 0165-5876/ ã 2014 Elsevier Ireland Ltd. All rights reserved.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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Subjects Twenty-five Flemish with CLP subjects responded positively to an invitation to participate in this study. They ranged in age from 6 to 17.9 years with a mean age of 10.6 years. Only subjects with nonsyndromic unilateral or bilateral CLP, no secondary pharyngeal
surgery, no cognitive deficiency, no neuromotor dysfunction or residual hard palate fistula and no acute nose, ear and throat diseases were invited. The subjects in the experimental group included 17 boys and 8 girls. All subjects with a unilateral CLP consulted the same craniofacial team and had undergone an identical surgical procedure. Surgical procedure of the lip was
Table 1 Summary of recent studies regarding the lip functions in children with cleft lip (and palate). CLP: cleft lip and palate, CL: cleft lip, U/BCLP: unilateral/bilateral cleft lip and palate; m.a.: mean age Authors
Patients
van Lieshout et al., 2002 [11]
9 CLP/m. a.:15.8 years 3 boys, 6 girls 4 controls/m. a.: 17.8 years 2 boys, 2 girls
1. Functional assessment of potential dif- Midsagittal articulography was used during
Trotman et al., 2005 [12]
16 CLP/m.a: 13.4 years 12 UCLP, 4 BCLP 8 boys, 8 girls 8 controls/m. a.: 10.5 years 4 boys, 4 girls 42 CL/m.a.: 13.3 years 12 boys, 30 girls 31 controls/ m.a.: 13.4 years 14 boys, 17 girls 32 CL (nonrevision CL) m.a.: 12.4 years 21 boys, 11 girls 31 CL (revision CL) m.a.: 12.1 years 18 boys, 13 girls 37 controls/ m.a.: 13.1 years 20 boys, 17 girls 15 unrepaired CLP m.a.: 3.20 months 9 boys, 6 girls 16 controls/ m.a.: 4.25 months 10 boys, 6 girls
1. Statistically analyzing facial movement Video recordings and measurements in three
Trotman et al., 2007 [13]
Trotman et al., 2007 [14]
Trotman et al., 2013 [15]
Nakatsuka et al., 2011 [16]
15 CLP/m.a.: 11.3 years 1 UCL, 5 UCLA, 9UCLP 8 boys, 7 girls 15 controls/ m.a.: 10.2 years 8 boys, 7 girls
Purpose
Methods
ferences in upper and lower lip kine- non-verbal and verbal tasks. matics and lip coupling.
Important results
1. Reduced upper lip movement ranges. 2. Variable spatiotemporal pattern for upper lip movement cycles.
3. More variable interlip coupling. 4. Linguistically more complex
tasks showed more variability in the individual upper and lower lip movement.
data.
1. To investigate lip force dynamics.
some patients with CLP more specifically a restricted antero-posterior movement of the upper lip. 2. Greater movement of the lower lip and chin regions to compensate for this upper lip impairment.
Measurement of fine motor control and compressions forces with upper and lower lip using an interdental yoke with lip saddle.
1. Subjects with a cleft of the upper lip had
1. To measure nasolabial movements in Three-dimensional movements were subjects with CLP.
1. Compensatory movements were seen in
dimensions of facial movement (smile, cheek puff, grimace, lip purse, mouth opening).
assessed using a video-based tracking system (38 landmarks) during maximum smile, cheek puff, lip purse, mouth opening and natural smile.
Seven measures of facial movement before 1. To collect dynamic facial images. 2. To determine differences in facial move- and 4 months after primary lip repair in CLP subjects and at similar time points in the ment. 3. To determine changes in facial move- control group. ments before and after primary lip repair.
1. To estimate effects of lip repair on the A multidirectional lip-closing force multidirectional lip-closing forces dur- measurement system. ing maximum pursing-like lip-closing movement.
increased contraction instability and elevated force recruitment rates of the lower lip. 2. A reduction in on-target force behavior and degradation in force control.
1. Lateral movements of the upper lip were greater than vertical movements.
2. The revision and nonrevision groups demonstrated 6–28% less upper lip movements (most restriction for smiling and greater asymmetry in upper lip movement).
1. The range of facial movements increased by 17% for all infants during the 4-month period. 2. Subjects with UCLP had 50% less nasolabial movement and no difference due to lip repair. 3. Subjects with U/B CLP had 58% and 118% greater lateral upper lip movement respectively. 4. Subjects with UCLP had 3.67 and BCLP 3.56 times greater asymmetry of movement before lip repair. Less problems after lip repair.
1. Identical forces were measured in all directions.
2. Identical total lip-closing forces were measured.
3. The vertical and oblique lip-closing forces are different between the cleft and the non-cleft side.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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performed (by the same surgeon) using a modified Millard technique without primary nose correction at an average age of 5.5 months (range 3–6.1 months). The cleft had been closed using one-stage Wardill-Kilner palatoplasty (by the same surgeon) at an average age of 12.5 months (range 11.9–20.1 months). All patients had been operated by the same surgical team and with the same surgical technique in the same conditions. At an average age of 8.03 years (range 7.09–11.6 years), bone grafting (preceded by orthodontic treatment) was performed. Twelve subjects had speech therapy for a minimum period of 8 months, twice a week. The goals of speech therapy were to establish correct phonetic placement and to eliminate compensatory articulations or speech developmental errors. The gender- and age-matched Flemish control group was randomly selected and consisted of 25 subjects (17 boys and 8 girls) with a mean age of 10.7 years (range 6.7–18.2 years). All children went to normal schools and had no history or presence of ear, nose and throat pathologies. No significant differences in age were found between the subjects in the experimental group and those in the control group (independent Student t-test, p = 0.959). For this study each subject in the control and experimental group was assessed by an otorhinolaryngologist who performed an examination to exclude nasal and ear pathologies using indirect laryngoscopy and macroscopic otoscopy. A Thudicum speculum was used to inspect the nose. Assessment with the Iowa Oral Performance Instrument The Iowa Oral Performance Instrument (IOPI) (model 2.1; IOPI medical LLC, Carnation, WA) was used to measure lip strength, tongue elevation strength [18–20] and tongue endurance. The IOPI is a small hand-held device that measures the amount of pressure on a small pliable air-filled bulb. The lip and tongue pressures are digitally displayed (kPa) on an LCD panel on the device. To ensure accurate measurement, calibration was checked and adjusted if necessary prior to obtaining measures from each participant. Every subject used a new bulb. During the assessments, the examiner used verbal encouragement. Lip strength (kPa) was assessed with the IOPI bulb between two wooden tongue blades as used in the assessment protocol of Clark and Solomon [21] (Fig. 1). This configuration distributed the pressure exerted on the blades evenly across the entire surface of the tongue bulb. The blades were positioned between the lips at midline. The subjects were instructed to protrude the lips and to push and squeeze the lips around the wooden tongue blades with maximum effort [21]. The lip strength was measured on the basis of three test trials with a brief resting period of 30 s between each trial. The highest pressure was used for the statistical analysis. The anterior tongue elevation strength (kPa) was assessed according the standard IOPI procedure [22] (Fig. 2). The speech bulb was positioned longitudinally along the hard palate prior to the upper alveolar ridge. Subjects were instructed to elevate the tongue tip against the bulb with maximum effort. The tongue elevation strength was measured on the basis of three test trials with a resting period of 30 s between each trial and the highest pressure value was used for further analysis. The tongue endurance (s) was measured following the anterior tongue elevation strength after a short break of 5 min. Subjects were instructed to elevate the tongue tip against the bulb and to sustain 50% of the maximal pressure for as long as possible. The highest time (on the basis of three test trials) was used for the statistical analysis.
Fig. 1. Lip strength was assessed with the IOPI bulb between two wooden tongue blades (as used in the assessment protocol of Clark and Solomon [21]).
Fig. 2. Tongue elevation strength is the maximum pressure of the tongue pressing against the hard palate. The IOPI measures this when the tongue bulb is placed in the position as seen in this figure (http://www.iopimedical.com/Tongue_Strength. html).
variables, an independent Student t-test was applied. A probability level of less than .05 was considered to be significant. Results Assessment with the Iowa Oral Performance Instrument
Statistical analysis SPSS version 21 was used for the statistical analysis of the data. To determine the significance level of difference of the continuous
In Table 2 the results of the IOPI measurement of the lip strength, anterior tongue elevation strength and tongue endurance in both the subjects with and without CLP are provided. No
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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Table 2 Results of the lip strength, anterior tongue elevation strength and tongue endurance in both the subjects with (n = 25) and without (n = 25) cleft lip and palate (CLP). *significant difference between the results of the subjects with and without CLP (significance level set at 0.05, independent Student t-test). Reference data (mean and range) as mentioned in the literature are provided. NA: no reference data from child studies available. IOPI assessment
Mean subjects with CLP SD
Lip strength (kPa) 21.6 Anterior tongue elevation strength (kPa) 37.2 Tongue endurance (s)
3.7
Mean subjects control group SD
5.5 20.7 15.3 43.0 2.3
3.9
significant difference was measured between the boys and girls with and without CLP. Discussion The present controlled study measured the lip and tongue strength in 25 subjects (mean age 10.6 years) with an unilateral CLP. Assessment of the lip function during growth is necessary to evaluate the surgical procedure of the lip. All subjects consulted the same craniofacial team and had undergone an identical surgical procedure with surgical closure of the lip using a modified Millard technique at an average age of 5.5 months and a one-stage Wardill-Kilner palatoplasty at an average age of 12.5 months. Bone grafting (preceded by orthodontic treatment) was performed at an average age of 8.03 years. The general goals of lip repair in unilateral clefts are: to reconstruct the lip as close to its normal anatomical and functional features as possible and to correct the nasal deformity to minimize the severity of secondary deformities [23]. Repositioning of the unilateral cleft lip includes positioning both sides of the lip at equal height to obtain balance and symmetry. On both sides of the cleft edges, the orbicularis oris muscles are maldirected and malpositioned, with abnormal attachments. The orbicularis oris muscle runs parallel to the edges of the cleft and inserts into the margins of the piriform fossa [24]. These muscles must be released on both sides, redirected, and sutured in a normal horizontal position to assure normal lip function [23]. The orbicularis oris muscle closes the lips, and helps protrude lips and shapes lip [25]. These lip strength functions were assessed in this study with the use of IOPI. When specific aspects of facial appearance are reported in literature, specifically the function of the lip, significant differences between the experimental and control group are obtained with a decreased satisfaction for the aesthetics of the lip in the cleft group [9,10]. In the study by Sinko et al. [9] 63% of the female subjects with CLP wanted upper lip correction. Also in a previous study of Van Lierde et al. [10] fifty-eight percent (19/33) of the children with CLP are satisfied or very satisfied (24%, 8/33) with the appearance of the lip, whilst 18% (6/33) are unsatisfied. Significantly more children with CLP (42%, 14/33, p = 0.03) are unsatisfied with the aesthetics of the lip in comparison with the control group. According to several authors primary lip repair is mostly the final lip repair because the aesthetic and functional results are excellent and no secondary correction is required. Following primary lip repair, the appearance and function of the lip will improve with time. This improvement is related to constant function of the lip and molding pressure from the lower lip [23,24,26–28]. In this study a normal lip strength (as measured with the IOPI) was present in the children with unilateral cleft lip and palate. The subjects were instructed to protrude the lips and to push and squeeze the lips around the wooden tongue blades with maximum effort [21]. The subjects with CLP in this study had a primary lip closure with a modified Millard technique. The lack of information regarding satisfaction with lip aesthetics can be regarded as a limitation of this study.
Level of significance Reference data [26]
5.5 .572 14.8 .189 3.7 .816
NA 49.8 (range: 42–58) Age group: 10.0–10.11, n = 5 males NA
In this study the anterior tongue elevation strength and tongue endurance was also measured with the IOPI. The tongue elevation strength is related to the action of the anterior portion of the genioglossus muscle which draws the root of the tongue anteriorly to exit the oral cavity or to press the apex on the alveolar ridge or teeth [25]. The palatal cleft has a major impact on physiology and has functional consequences [28,29]. In cleft palate the tongue rises higher than usual during elevation of the aero-digestive bract, which represents the first phase of deglutition [28,29]. The anterior tongue elevation strength and tongue endurance are normal in children with unilateral CLP as measured with the IOPI. No significant differences were obtained between the subjects with and without cleft lip and palate. The IOPI is an ideal instrument for the measurement of lip and tongue strength and endurance in isolated conditions because it is psychologically and physically noninvasive and the results are easy to interpret. According to Barlow [25] the complex arrangement of interdigitating muscle fibers in the lower face makes the lips rater difficult structures to study during force tasks. Although accessibility is good, establishing the biomechanical properties of the lips is further complicated by other factors including lip-jaw relations, dentition, facial asymmetry, and muscle length [24]. Especially in the cleft lip and palate patients the abnormal facial morphology, the possible presence of a mid-face retrusion and poor facial growth in repaired CLP is still an extremely complex subject [26,27]. The IOPI can assist in the quantification of perceptual judgments and facilitate the sharing of information of subjects with oral problems. The relationship between orofacial motor control during specific lip (IOPI) measures and during lip tasks used in daily life (oromyo functional assessment) is still subject for further research. Conclusion In conclusion the results of this controlled study demonstrated normal lip and tongue functions in young subjects with unilateral CLP as measured with the IOPI. The surgical correction of the pathological lip anatomy leads to a normal lip function in these subjects with a unilateral CLP. The ENT specialists and speech pathologists must be aware of this aspect. Conflict of interest No conflict of interest declared. Acknowledgements Our research was made possible by the cooperation and support of the children with cleft palate. This study was approved by the human subject committee of the Ghent University (B670201215561). The patients provided signed consent to publish the data. The authors have no competing interests to declare and no author had any paid consultancy or any other conflict of interest. The authors have no financial disclosures to report on this article.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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References [1] T. Millard, L. Richman, Different cleft conditions, facial appearance, and speech: relationship to psychological variables, Cleft Palate Craniofac. J. 38 (4) (2001) 68–75. [2] Z. Berger, L. Dalton, Coping with a cleft: psychosocial adjustment of adolescents with a cleft lip and palate and their parents, Cleft Palate Craniofac. J. 46 (4) (2009) 435–443. [3] O. Hunt, D. Burden, P. Hepper, M. Stevenson, C. Johnston, Self-reports of psychosocial functioning among children and young adults with cleft lip and palate, Cleft Palate Craniofac. J. 43 (5) (2006) 598–605. [4] P. Thomas, S. Turner, N. Rumsey, T. Dowell, J. Sandy, Satisfaction with facial appearance among subjects affected by a cleft, Cleft Palate Craniofac. J. 34 (3) (1997) 226–231. [5] C. Havstam, A. Lohmander, A. Dahlgren Sandberg, A. Elander, Speech and satisfaction with outcome of treatment in young adults with unilateral or bilateral complete clefts, Scand. J. Plast. Reconstr. Surg. Hand Surg. 42 (4) (2008) 182–189. [6] A. Marcusson, G. Paulin, L. Ostrup, Facial appearance in adults who had cleft lip and palate treated in childhood, Scand. J. Plast. Reconstr. Surg. Hand Surg. 36 (1) (2002) 16–23. [7] S. Noor, S. Musa, Assessment of patients’ level of satisfaction with cleft treatment using the Cleft Evaluation Profile, Cleft Palate Craniofac. J. 44 (3) (2007) 292–303. [8] B. Oosterkamp, P. Dijkstra, H. Remmelink, R. van Oort, S. Goorhuis-Brouwer, A. A. Sandham, et al., Satisfaction with treatment outcome in bilateral cleft lip and palate patients, Int. J. Oral Maxillofac. Surg. 36 (10) (2007) 890–895. [9] K. Sinko, R. Jagsch, V. Prechtl, F. Watzinger, K. Hollmann, A. Baumann, Evaluation of esthetic, functional, and quality-of-life outcome in adult cleft lip and palate patients, Cleft Palate Craniofac. J. 42 (4) (2005) 355–361. [10] K. Van Lierde, E. Dhaeseleer, A. Luyten, K. Van De Woestijne, H. Vermeersch, N. Roche, Parent and child ratings of satisfaction with speech and facial appearance in Flemish pre-pubescent boys and girls with unilateral cleft lip and palate, Int. J. Oral Maxillofac. Surg. 41 (2) (2012) 192–199. [11] P. van Lieshout, C. Rutjens, P. Spauwen, The dynamics of interlip coupling in speakers with a repaired unilateral cleft-lip history, J. Speech Lang. Hear. Res. 45 (1) (2002) 5–19. [12] C. Trotman, J. Faraway, C. Phillips, Visual and statistical modeling of facial movement in patients with cleft lip and palate, Cleft Palate Craniofac. J. 42 (3) (2005) 245–254. [13] C. Trotman, S. Barlow, J. Faraway, Functional outcomes of cleft lip surgery. Part III: Measurement of lip forces, Cleft Palate Craniofac. J. 44 (6) (2007) 617–623.
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[14] C. Trotman, J. Faraway, H. Losken, J. van Aalst, Functional outcomes of cleft lip surgery. Part II: Quantification of nasolabial movement, Cleft Palate Craniofac. J. 44 (6) (2007) 607–616. [15] C. Trotman, J. Faraway, R. Soltmann, T. Hartman, J. van Aalst, Facial soft tissue dynamics before and after primary lip repair, Cleft Palate Craniofac. J. 50 (3) (2013) 315–322. [16] K. Nakatsuka, T. Adachi, T. Kato, M. Murakami, K. Yamada, Y. Masuda, Asymmetric lip-closing forces in children with repaired unilateral cleft lip and/ or palate, J. Oral Rehabil. 38 (12) (2011) 921–928. [17] IOPI Medical LLC, Redmond: IOPI Medical LLC. http://www.iopimedical.com/ Images/PDFs/800-2301-01%20LS1,%20EN,%20IOPI%202.3%20User%20Manual, %20WEB.pdf, 2005 (accessed 27.09.13). [18] H. Clark, P. Henson, W. Barbe, J. Stierwalt, M. Sherrill, Relationships among subjective and objective measures of tongue strength and oral phase swallowing impairments, Am. J. Speech Lang. Pathol. 12 (1) (2003) 40–50. [19] D. Robin, A. Goel, L. Somodi, E. Luschei, Tongue strength and endurance: relation to highly skilled movements, J. Speech Hear. Res. 35 (6) (1992) 1239–1245. [20] C. Lazarus, J. Logemann, C. Huang, A. Rademaker, Effects of two types of tongue strengthening exercises in young normals, Folia Phoniatr. Logop. 55 (4) (2003) 199–205. [21] H. Clark, N. Solomon, Age and sex differences in orofacial strength, Dysphagia 27 (1) (2012) 2–9. [22] J. Vanderwegen, C. Guns, G. Van Nuffelen, R. Elen, M. De Bodt, The influence of age, sex, bulb position, visual feedback, and the order of testing on maximum anterior and posterior tongue strength and endurance in healthy belgian adults, Dysphagia 28 (2) (2013) 159–166. [23] J. Baradach, K. Salyer, Cleft classification and cleft lip repair, in: J. Shprintzen, J. Bardach (Eds.), Cleft Palate Speech Management, Mosby, St. Louis, 1995. [24] A. Watson, Primary surgery, in: A. Watson, D. Sell, P. Grunwell (Eds.), Management of cleft lip and palate, Whurr, London, 2004. [25] S. Barlow, Handbook of Clinical Speech Physiology, Singular, San Diego, 1999. [26] A. Kummer, Cleft Palate and Craniofacial anomalies, Singular, Canada, 2001. [27] A. Watson, D. Sell, P. Grunwell, Management of Cleft Lip and Palate, Whurr, Philadelphia, 2004. [28] S. Peterson-Falzone, M. Hardin-Jones, M. Karnell, Surgical management of cleft lip and palate, in: S. Peterson-Falzone, M. Hardin-Jones, M. Karnell (Eds.), Cleft Palate Speech, Mosby, St. Louis, 2001. [29] R. Malek, Cleft Lip and Palate, Lesions, Pathophysiology and Primary Treatment, Martin Dunitz, London, 2001.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
International Journal of Pediatric Otorhinolaryngology xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Oral strength in subjects with a unilateral cleft lip and palate Kristiane M. Van Lierde a, *, Kim Bettens a , Anke Luyten a , Janne Plettinck a , Katrien Bonte b , Hubert Vermeersch b , Nathalie Roche c a
Department of Speech, Language and Hearing Sciences, Ghent University, Belgium Department of Head and Neck Surgery, Ghent University Hospital, Belgium c Department of Plastic Surgery, Ghent University Hospital, Belgium b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 24 February 2014 Received in revised form 9 May 2014 Accepted 13 May 2014 Available online xxx
Purpose: Facial appearance and speech outcome may affect psychosocial functioning in girls and boys. Several studies reported dissatisfaction with facial appearance and more specifically the lip and mouth profile in children with cleft lip and palate (CLP). The purpose of this controlled study was to measure the tongue and lip strength and endurance in boys and girls with CLP. Methods: Twenty-five subjects (mean age: 10.6 years) with a unilateral CLP and a gender- and agematched control group were selected. All subjects with an unilateral CLP consulted the same craniofacial team and had undergone an identical surgical procedure. Surgical procedure of the lip was performed using a modified Millard technique without primary nose correction at an average age of 5.5 months. The Iowa Oral Performance instrument was used to measure lip and tongue strength and tongue endurance. Results: The results of the Iowa Oral Performance measurement showed no significant differences between the subjects with an unilateral cleft lip and palate and the age and gender matched control group without a cleft lip and palate. Conclusion: There is no significant differences regarding oral strength more specifically the lip and tongue strength and endurance between subjects with and without an unilateral cleft lip and palate. ENT specialists and speech pathologists must be aware of this aspect of the normal lip and tongue functions. ã 2014 Elsevier Ireland Ltd. All rights reserved.
Keywords: Cleft lip and palate Iowa Oral Performance Instrument Lip strength Tongue strength Tongue endurance
Introduction Facial appearance and speech outcome may affect psychosocial functioning [1] in girls and boys. Several studies reported dissatisfaction with facial appearance [1–4] and more specifically the lip and mouth profile [5–10] in children with cleft lip and palate. An appropriate lip and also tongue function is essential for facial aesthetics (e.g., lip competence, interdental tongue behavior), speech production and non-verbal functions like chewing, swallowing and facial emotional readability. Few authors assessed oral strength in children with cleft lip and palate. Table 1 provides a summary of recent studies regarding lip strength in children with cleft lip and palate. Several studies reported restrictions and/or compensatory behavior in upper lip or nasolabial movements [11–15] and one study [11] mentioned variable interlip coupling. Some of these studies were performed in specific controlled test situations with
* Corresponding author at: Department of Speech, Language and Hearing Sciences, Ghent University Hospital, ENT 2P1, De Pintelaan 185, 9000, Gent, Belgium. Tel.: +09 332 23 32 . E-mail address: [email protected] (K.M. Van Lierde).
for example the use of a midsagittal articulograph [11] or the use of an instrument with an interdental yoke and lip saddle [13]. Moreover, small control groups [11] or no age- [12,15] and gendermatched [11,12] control groups were used. Studies clearly identifying specific outcome measures in both boys and girls with clefts regarding oral strength have the power to evaluate cleft related surgical techniques (e.g., the type and timing of primary lip closure and revisions of the lip repair). The purpose of this controlled study was to measure the tongue and lip strength and endurance using the Iowa Oral Performance Instrument (IOPI) [17] in boys and girls with unilateral cleft lip and palate (CLP). Assessment of the lip function is necessary to evaluate the surgical procedure of the lip. All patients were treated by the craniofacial team of the Ghent University Hospital. Based on the results of previous reports in the literature, a decreased lip strength was hypothesized in subjects with clefts compared with subjects without a cleft. Methods and materials This study was approved by the Human Subject Committee of the Ghent University (B670201215561).
http://dx.doi.org/10.1016/j.ijporl.2014.05.017 0165-5876/ ã 2014 Elsevier Ireland Ltd. All rights reserved.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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Subjects Twenty-five Flemish with CLP subjects responded positively to an invitation to participate in this study. They ranged in age from 6 to 17.9 years with a mean age of 10.6 years. Only subjects with nonsyndromic unilateral or bilateral CLP, no secondary pharyngeal
surgery, no cognitive deficiency, no neuromotor dysfunction or residual hard palate fistula and no acute nose, ear and throat diseases were invited. The subjects in the experimental group included 17 boys and 8 girls. All subjects with a unilateral CLP consulted the same craniofacial team and had undergone an identical surgical procedure. Surgical procedure of the lip was
Table 1 Summary of recent studies regarding the lip functions in children with cleft lip (and palate). CLP: cleft lip and palate, CL: cleft lip, U/BCLP: unilateral/bilateral cleft lip and palate; m.a.: mean age Authors
Patients
van Lieshout et al., 2002 [11]
9 CLP/m. a.:15.8 years 3 boys, 6 girls 4 controls/m. a.: 17.8 years 2 boys, 2 girls
1. Functional assessment of potential dif- Midsagittal articulography was used during
Trotman et al., 2005 [12]
16 CLP/m.a: 13.4 years 12 UCLP, 4 BCLP 8 boys, 8 girls 8 controls/m. a.: 10.5 years 4 boys, 4 girls 42 CL/m.a.: 13.3 years 12 boys, 30 girls 31 controls/ m.a.: 13.4 years 14 boys, 17 girls 32 CL (nonrevision CL) m.a.: 12.4 years 21 boys, 11 girls 31 CL (revision CL) m.a.: 12.1 years 18 boys, 13 girls 37 controls/ m.a.: 13.1 years 20 boys, 17 girls 15 unrepaired CLP m.a.: 3.20 months 9 boys, 6 girls 16 controls/ m.a.: 4.25 months 10 boys, 6 girls
1. Statistically analyzing facial movement Video recordings and measurements in three
Trotman et al., 2007 [13]
Trotman et al., 2007 [14]
Trotman et al., 2013 [15]
Nakatsuka et al., 2011 [16]
15 CLP/m.a.: 11.3 years 1 UCL, 5 UCLA, 9UCLP 8 boys, 7 girls 15 controls/ m.a.: 10.2 years 8 boys, 7 girls
Purpose
Methods
ferences in upper and lower lip kine- non-verbal and verbal tasks. matics and lip coupling.
Important results
1. Reduced upper lip movement ranges. 2. Variable spatiotemporal pattern for upper lip movement cycles.
3. More variable interlip coupling. 4. Linguistically more complex
tasks showed more variability in the individual upper and lower lip movement.
data.
1. To investigate lip force dynamics.
some patients with CLP more specifically a restricted antero-posterior movement of the upper lip. 2. Greater movement of the lower lip and chin regions to compensate for this upper lip impairment.
Measurement of fine motor control and compressions forces with upper and lower lip using an interdental yoke with lip saddle.
1. Subjects with a cleft of the upper lip had
1. To measure nasolabial movements in Three-dimensional movements were subjects with CLP.
1. Compensatory movements were seen in
dimensions of facial movement (smile, cheek puff, grimace, lip purse, mouth opening).
assessed using a video-based tracking system (38 landmarks) during maximum smile, cheek puff, lip purse, mouth opening and natural smile.
Seven measures of facial movement before 1. To collect dynamic facial images. 2. To determine differences in facial move- and 4 months after primary lip repair in CLP subjects and at similar time points in the ment. 3. To determine changes in facial move- control group. ments before and after primary lip repair.
1. To estimate effects of lip repair on the A multidirectional lip-closing force multidirectional lip-closing forces dur- measurement system. ing maximum pursing-like lip-closing movement.
increased contraction instability and elevated force recruitment rates of the lower lip. 2. A reduction in on-target force behavior and degradation in force control.
1. Lateral movements of the upper lip were greater than vertical movements.
2. The revision and nonrevision groups demonstrated 6–28% less upper lip movements (most restriction for smiling and greater asymmetry in upper lip movement).
1. The range of facial movements increased by 17% for all infants during the 4-month period. 2. Subjects with UCLP had 50% less nasolabial movement and no difference due to lip repair. 3. Subjects with U/B CLP had 58% and 118% greater lateral upper lip movement respectively. 4. Subjects with UCLP had 3.67 and BCLP 3.56 times greater asymmetry of movement before lip repair. Less problems after lip repair.
1. Identical forces were measured in all directions.
2. Identical total lip-closing forces were measured.
3. The vertical and oblique lip-closing forces are different between the cleft and the non-cleft side.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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performed (by the same surgeon) using a modified Millard technique without primary nose correction at an average age of 5.5 months (range 3–6.1 months). The cleft had been closed using one-stage Wardill-Kilner palatoplasty (by the same surgeon) at an average age of 12.5 months (range 11.9–20.1 months). All patients had been operated by the same surgical team and with the same surgical technique in the same conditions. At an average age of 8.03 years (range 7.09–11.6 years), bone grafting (preceded by orthodontic treatment) was performed. Twelve subjects had speech therapy for a minimum period of 8 months, twice a week. The goals of speech therapy were to establish correct phonetic placement and to eliminate compensatory articulations or speech developmental errors. The gender- and age-matched Flemish control group was randomly selected and consisted of 25 subjects (17 boys and 8 girls) with a mean age of 10.7 years (range 6.7–18.2 years). All children went to normal schools and had no history or presence of ear, nose and throat pathologies. No significant differences in age were found between the subjects in the experimental group and those in the control group (independent Student t-test, p = 0.959). For this study each subject in the control and experimental group was assessed by an otorhinolaryngologist who performed an examination to exclude nasal and ear pathologies using indirect laryngoscopy and macroscopic otoscopy. A Thudicum speculum was used to inspect the nose. Assessment with the Iowa Oral Performance Instrument The Iowa Oral Performance Instrument (IOPI) (model 2.1; IOPI medical LLC, Carnation, WA) was used to measure lip strength, tongue elevation strength [18–20] and tongue endurance. The IOPI is a small hand-held device that measures the amount of pressure on a small pliable air-filled bulb. The lip and tongue pressures are digitally displayed (kPa) on an LCD panel on the device. To ensure accurate measurement, calibration was checked and adjusted if necessary prior to obtaining measures from each participant. Every subject used a new bulb. During the assessments, the examiner used verbal encouragement. Lip strength (kPa) was assessed with the IOPI bulb between two wooden tongue blades as used in the assessment protocol of Clark and Solomon [21] (Fig. 1). This configuration distributed the pressure exerted on the blades evenly across the entire surface of the tongue bulb. The blades were positioned between the lips at midline. The subjects were instructed to protrude the lips and to push and squeeze the lips around the wooden tongue blades with maximum effort [21]. The lip strength was measured on the basis of three test trials with a brief resting period of 30 s between each trial. The highest pressure was used for the statistical analysis. The anterior tongue elevation strength (kPa) was assessed according the standard IOPI procedure [22] (Fig. 2). The speech bulb was positioned longitudinally along the hard palate prior to the upper alveolar ridge. Subjects were instructed to elevate the tongue tip against the bulb with maximum effort. The tongue elevation strength was measured on the basis of three test trials with a resting period of 30 s between each trial and the highest pressure value was used for further analysis. The tongue endurance (s) was measured following the anterior tongue elevation strength after a short break of 5 min. Subjects were instructed to elevate the tongue tip against the bulb and to sustain 50% of the maximal pressure for as long as possible. The highest time (on the basis of three test trials) was used for the statistical analysis.
Fig. 1. Lip strength was assessed with the IOPI bulb between two wooden tongue blades (as used in the assessment protocol of Clark and Solomon [21]).
Fig. 2. Tongue elevation strength is the maximum pressure of the tongue pressing against the hard palate. The IOPI measures this when the tongue bulb is placed in the position as seen in this figure (http://www.iopimedical.com/Tongue_Strength. html).
variables, an independent Student t-test was applied. A probability level of less than .05 was considered to be significant. Results Assessment with the Iowa Oral Performance Instrument
Statistical analysis SPSS version 21 was used for the statistical analysis of the data. To determine the significance level of difference of the continuous
In Table 2 the results of the IOPI measurement of the lip strength, anterior tongue elevation strength and tongue endurance in both the subjects with and without CLP are provided. No
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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Table 2 Results of the lip strength, anterior tongue elevation strength and tongue endurance in both the subjects with (n = 25) and without (n = 25) cleft lip and palate (CLP). *significant difference between the results of the subjects with and without CLP (significance level set at 0.05, independent Student t-test). Reference data (mean and range) as mentioned in the literature are provided. NA: no reference data from child studies available. IOPI assessment
Mean subjects with CLP SD
Lip strength (kPa) 21.6 Anterior tongue elevation strength (kPa) 37.2 Tongue endurance (s)
3.7
Mean subjects control group SD
5.5 20.7 15.3 43.0 2.3
3.9
significant difference was measured between the boys and girls with and without CLP. Discussion The present controlled study measured the lip and tongue strength in 25 subjects (mean age 10.6 years) with an unilateral CLP. Assessment of the lip function during growth is necessary to evaluate the surgical procedure of the lip. All subjects consulted the same craniofacial team and had undergone an identical surgical procedure with surgical closure of the lip using a modified Millard technique at an average age of 5.5 months and a one-stage Wardill-Kilner palatoplasty at an average age of 12.5 months. Bone grafting (preceded by orthodontic treatment) was performed at an average age of 8.03 years. The general goals of lip repair in unilateral clefts are: to reconstruct the lip as close to its normal anatomical and functional features as possible and to correct the nasal deformity to minimize the severity of secondary deformities [23]. Repositioning of the unilateral cleft lip includes positioning both sides of the lip at equal height to obtain balance and symmetry. On both sides of the cleft edges, the orbicularis oris muscles are maldirected and malpositioned, with abnormal attachments. The orbicularis oris muscle runs parallel to the edges of the cleft and inserts into the margins of the piriform fossa [24]. These muscles must be released on both sides, redirected, and sutured in a normal horizontal position to assure normal lip function [23]. The orbicularis oris muscle closes the lips, and helps protrude lips and shapes lip [25]. These lip strength functions were assessed in this study with the use of IOPI. When specific aspects of facial appearance are reported in literature, specifically the function of the lip, significant differences between the experimental and control group are obtained with a decreased satisfaction for the aesthetics of the lip in the cleft group [9,10]. In the study by Sinko et al. [9] 63% of the female subjects with CLP wanted upper lip correction. Also in a previous study of Van Lierde et al. [10] fifty-eight percent (19/33) of the children with CLP are satisfied or very satisfied (24%, 8/33) with the appearance of the lip, whilst 18% (6/33) are unsatisfied. Significantly more children with CLP (42%, 14/33, p = 0.03) are unsatisfied with the aesthetics of the lip in comparison with the control group. According to several authors primary lip repair is mostly the final lip repair because the aesthetic and functional results are excellent and no secondary correction is required. Following primary lip repair, the appearance and function of the lip will improve with time. This improvement is related to constant function of the lip and molding pressure from the lower lip [23,24,26–28]. In this study a normal lip strength (as measured with the IOPI) was present in the children with unilateral cleft lip and palate. The subjects were instructed to protrude the lips and to push and squeeze the lips around the wooden tongue blades with maximum effort [21]. The subjects with CLP in this study had a primary lip closure with a modified Millard technique. The lack of information regarding satisfaction with lip aesthetics can be regarded as a limitation of this study.
Level of significance Reference data [26]
5.5 .572 14.8 .189 3.7 .816
NA 49.8 (range: 42–58) Age group: 10.0–10.11, n = 5 males NA
In this study the anterior tongue elevation strength and tongue endurance was also measured with the IOPI. The tongue elevation strength is related to the action of the anterior portion of the genioglossus muscle which draws the root of the tongue anteriorly to exit the oral cavity or to press the apex on the alveolar ridge or teeth [25]. The palatal cleft has a major impact on physiology and has functional consequences [28,29]. In cleft palate the tongue rises higher than usual during elevation of the aero-digestive bract, which represents the first phase of deglutition [28,29]. The anterior tongue elevation strength and tongue endurance are normal in children with unilateral CLP as measured with the IOPI. No significant differences were obtained between the subjects with and without cleft lip and palate. The IOPI is an ideal instrument for the measurement of lip and tongue strength and endurance in isolated conditions because it is psychologically and physically noninvasive and the results are easy to interpret. According to Barlow [25] the complex arrangement of interdigitating muscle fibers in the lower face makes the lips rater difficult structures to study during force tasks. Although accessibility is good, establishing the biomechanical properties of the lips is further complicated by other factors including lip-jaw relations, dentition, facial asymmetry, and muscle length [24]. Especially in the cleft lip and palate patients the abnormal facial morphology, the possible presence of a mid-face retrusion and poor facial growth in repaired CLP is still an extremely complex subject [26,27]. The IOPI can assist in the quantification of perceptual judgments and facilitate the sharing of information of subjects with oral problems. The relationship between orofacial motor control during specific lip (IOPI) measures and during lip tasks used in daily life (oromyo functional assessment) is still subject for further research. Conclusion In conclusion the results of this controlled study demonstrated normal lip and tongue functions in young subjects with unilateral CLP as measured with the IOPI. The surgical correction of the pathological lip anatomy leads to a normal lip function in these subjects with a unilateral CLP. The ENT specialists and speech pathologists must be aware of this aspect. Conflict of interest No conflict of interest declared. Acknowledgements Our research was made possible by the cooperation and support of the children with cleft palate. This study was approved by the human subject committee of the Ghent University (B670201215561). The patients provided signed consent to publish the data. The authors have no competing interests to declare and no author had any paid consultancy or any other conflict of interest. The authors have no financial disclosures to report on this article.
Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
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Please cite this article in press as: K.M. Van Lierde, et al., Oral strength in subjects with a unilateral cleft lip and palate, Int. J. Pediatr. Otorhinolaryngol. (2014), http://dx.doi.org/10.1016/j.ijporl.2014.05.017
