Role of Myofunctional Appliances on Children with Anterior Open Bite and Tongue Thrusting- An Original Research
Prateek Shakti
1, Khushtar Haider
21MDS, Senior resident, Department of Dentistry, All India Institute of Medical Sciences, Bhopal (M.P.), India;
2MDS, Senior resident, Department of Dentistry, Government Medical College, Datia (M.P.), India Corresponding author:
Dr. Khushtar Haider, MDS, Senior resident, Department of Dentistry, Government Medical College, Datia (M.P.), India, E-mail: [email protected]
ABSTRACT:
Background: Anterior open bite is one of the commonly occurring malocclusion among young population. The present study was conducted to assess the role of Myofunctional appliances on children with anterior open bite and tongue thrusting.
Materials & Methods: This study included 40 children age ranged 8- 12 years of both genders.
Children were divided into 2 groups of 20 each. Group I were those who received Myofunctional appliance therapy and Group II (Control) children were those who did not receive Myofunctional appliance therapy. Patients were divided based on presence of unilateral or bilateral transversal cross-bite, thus each group had two subgroups, patients treated with and without arch expansion.
The maximum tongue elevation strength was measured in kilopascal using the Iowa oral performance instrument (IOPA) system at baseline (T0), at the end of treatment (T1) and after 6 months of follow-up (T2).Tongue posture at rest, swallowing pattern and articulation were also examined.
Results: Maximum tongue elevation pressure at T0 in orofacial myofunctional therapy (MYO) was 36.5, in Non-OMT (CON) was 43.1, in orofacial myofunctional therapy group (COMBI) was 48.5 and in Non-OMT (EXP) ((treated with removable expansion devices) was 38.5. At T1 in orofacial myofunctional therapy group (MYO) was 44.3, in Non-OMT (CON) was 44.5, in orofacial myofunctional therapy (COMBI) was 51.4 and in Non-OMT (EXP) was 39.8. At T2 in orofacial myofunctional therapy (MYO) was 46.7, in Non-OMT (CON) was 44.2, in orofacial myofunctional therapy (COMBI) was 52.8 and in Non-OMT (EXP) was 37.2. The difference was significant (P< 0.05). A non- significant difference in group I and group II regarding AOT, tongue posture at rest, swallowing pattern (water), swallowing pattern (solid), articulation /l,n,d,t/ and articulation /s/ recorded at T1 and T2 (P> 0.05).
Conclusion: Authors found that OMT can positively influence tongue behaviour.OMT changed tongue elevation strength, tongue posture at rest, and tongue position during swallowing of solid food. However, large scale studies are required to substantiate the results found in this study.
Key words: Anterior open bite, Myofunctional appliances, Tongue elevation pressure
INTRODUCTION
Anterior open bite (AOB) is one of the commonly occurring malocclusion among young population. There are numerous causes for this anomaly. Among all, mouth breathing, thumb or digit sucking and lip or tongue thrusting are common.1 In anterior open bite, posterior teeth are in occlusion but anterior teeth are not in occlusion as there is space between incisors of both arches.
This is the major cause of unaesthetic appearance among children. As there is increased concern about facial esthetic, patients usually seek orthodontic consultation. Orthodontists play an important role in aligning teeth in occlusion such as in case of anterior open bite, posterior open bite, rotation, tipping, transposition, proclination, retroclination etc.2
Tongue thrusting is also one of the commonly occurring parafunctional habits. It has been observed in various studies that functional tongue movements during swallowing are correlating with anterior open bite.3 People with partial anterior open bite and incorrect tongue position shows altered gnostic sensibility of the tongue, which is a symptom of disturbed sensorimotor coordination resulting in imprecise action and reduced vertical movement of the tongue. Thus abnormal tongue positioning during deglutition should be considered as cause of AOB. Those who have the habit of swallowing without touching tip of tongue with hard palate tend to place it between incisors tip.4
Myofunctional appliances have gained attention in last couple of years with extreme good results. Before Myofunctional appliances, many studies have mentioned the role of fixed orthodontics in the correction of AOB, but results are not fully successful.5 The present study was conducted to assess the role of Myofunctional appliances on children with anterior open bite and tongue thrusting.
MATERIALS & METHODS
This study included 40 children age ranged 8- 12 years of both genders who visited the department of Orthodontics for correction of anterior open bite. The study was approved from institutional ethical committee. Parents of children were informed regarding the study and with their written consent, the study was commenced.
Data related to children such as name, age, gender etc. was recorded. Children were divided into 2 groups of 20 each. Group I were those who received orofacial Myofunctional therapy and Group II children were those who did not receive orofacial Myofunctional therapy. Patients were divided based on presence of unilateral or bilateral a transversal cross-bite, thus each group had two subgroups, patients treated with and without arch expansion. If no cross-bite was present, the subjects were sub-grouped to MYO subgroup and CON subgroup. Children in the MYO subgroup were subjected to 10 hours of myofuctional treatment followed by same exercises at home. The CON subgroup was observed after 6 months without treatment.
If a cross-bite was present, the children were divided into the EXP subgroup (treated with removable expansion devices) or COMBI subgroup (first underwent 10 hours of orofacial myofunctional therapy (OMT), followed by a treatment with a removable expansion device).
The removable expansion device consisted of an acrylic resin plate with coverage of the occlusal surfaces of the posterior teeth and a jack-screw which was activated 1–2 times a week by the patient.
The maximum tongue elevation strength was measured using the IOPI system at baseline (T0), at the end of treatment (T1) and after 6 months of follow-up (T2). Tongue posture at rest, swallowing pattern and articulation were also examined. During swallowing the lips were gently separated to visualize tongue position. Tongue position during the production of the sounds /l,n,d,t,s/ was recorded as the child spoke Dutch test sentences and words. Results were analyzed statistically.
RESULTS
Table I Distribution of patients
Group I (OMT) (20) Group II (Non- OMT) (20) Posterior cross-
bite absent
Posterior cross-bite present
Posterior cross-bite absent
Posterior cross-bite present
10 10 10 10
Table I shows distribution of patients based on OMT and non OMT and based on whether posterior cross-bite was present or absent. Group I had 20 and group II had 20 patients each having 10 patients each in sub groups.
Table II Assessment of maximum tongue elevation pressure in both groups Mean
pressure
No expansion Expansion P value
OMT (MYO) Non-OMT (CON)
OMT (COMBI)
Non-OMT (EXP)
T0 36.5 43.1 48.5 38.5 0.05
T1 44.3 44.5 51.4 39.8 0.02
T2 46.7 44.2 52.8 37.2 0.01
Table II, graph I shows that maximum tongue elevation pressure (kiloPascal) at T0 in OMT (MYO) was 36.5, in Non-OMT (CON) was 43.1, in OMT (COMBI) was 48.5 and in Non-OMT (EXP) was 38.5. At T1 in OMT (MYO) was 44.3, in Non-OMT (CON) was 44.5, in OMT (COMBI) was 51.4 and in Non-OMT (EXP) was 39.8. At T2 in OMT (MYO) was 46.7, in Non- OMT (CON) was 44.2, in OMT (COMBI) was 52.8 and in Non-OMT (EXP) was 37.2. The difference was significant (P< 0.05).
Graph I Maximum tongue elevation pressure in both groups
T0, No expansion OMT (MYO), 36.5
T0, No expansion Non-OMT (CON), 43.1
T0, Expansion OMT (COMBI), 48.5
T0, Expansion Non-OMT (EXP), 38.5 T1, No expansion OMT
(MYO), 44.3
T1, No expansion Non-OMT (CON), 44.5
T1, Expansion OMT
(COMBI), 51.4 T1, Expansion Non-OMT
(EXP), 39.8 T2, No expansion OMT
(MYO), 46.7
T2, No expansion Non-OMT (CON), 44.2
T2, Expansion OMT (COMBI), 52.8
T2, Expansion Non-OMT (EXP), 37.2
T0 T1 T2
Table III Comparison of variables in both groups
Variables Time Group I Group II P value
AOT T1 2 1 0.51
T2 7 1 0.23
Tongue posture at rest T1 6 0 0.07
T2 7 1 0.25
Swallowing pattern (water) T1 4 1 0.16
T2 5 1 0.19
Swallowing pattern (solid) T1 6 1 0.14
T2 5 0 0.08
Articulation /l,n,d,t/ T1 3 1 0.32
T2 1 2 0.91
Articulation /s/ T1 7 4 0.15
T2 2 3 0.25
Table III non- significant difference in group I and group II regarding AOT, tongue posture at rest, swallowing pattern (water), swallowing pattern (solid), articulation /l,n,d,t/ and articulation /s/ recorded at T1 and T2 (P> 0.05).
DISCUSSION
Orthodontists pay an important role in correcting dental and skeletal anomalies in patients. The skill, knowledge and experience of orthodontists determine the outcome of treatment. Which treatment is to be given in which patient, is solely the decision of the doctor. Anterior or posterior open bite treatment comprise of bonded or removable appliances to eliminate destructive habits.6 Similarly the use of intra- or extraoral appliances brings back vertical maxillary growth. In severe cases, the use of orthognathic surgery may be helpful. However, the concept of zygoma implants may be fruitful to control or even minimize the maxillary dentoalveolar dimensions.7The present study was conducted to assess the role of Myofunctional appliances on children with anterior open bite and tongue thrusting.
In our study, we enrolled, 40 children age ranged 12- 15 years which were randomly assigned into Group I and Group II. Group I was OMT and Group II was non- OMT group. Each group was further sub- divided based on whether posterior cross-bite present or not.
Van et al8 included 22 children which were divided into OMT and non-OMT groups. OMT did significantly change tongue elevation strength, tongue posture at rest, and tongue position during swallowing of solid food. At T2 more OMT subjects had contact between the lower central incisors and their antagonists or palate. More OMT subjects performed a physiological pattern of water swallowing than non-OMT children at T1 and T2. Articulation of /s,l,n,d,t/ was not improved by OMT. No interaction between OMT and expansion was found for any of the parameters.
We found that maximum tongue elevation pressure at T0 in OMT (MYO) was 36.5, in non-OMT (CON) was 43.1, in OMT (COMBI) was 48.5 and in non-OMT (EXP) was 38.5. At T1 in OMT (MYO) was 44.3, in non-OMT (CON) was 44.5, in OMT (COMBI) was 51.4 and in non-OMT (EXP) was 39.8. At T2 in OMT (MYO) was 46.7, in non-OMT (CON) was 44.2, in OMT (COMBI) was 52.8 and in non-OMT (EXP) was 37.2.
Numerous methods such as force sensitive resistors, strain-gauge manometry and IOPI system
swallowing problems are presumed to have tongue strength significantly lower than in normal subjects. Potter and Short9 in their study suggested that IOPI is a reliable method for evaluating maximum tongue strength in pediatric patients.
We found non- significant difference in Group I and Group II regarding AOT, tongue posture at rest, swallowing pattern (water), swallowing pattern (solid), articulation /l,n,d,t/ and articulation /s/ recorded at T1 and T2. In various studies it has been found that patients of AOB with habits of tongue thrusting, speech errors and low forward tongue rest posture are more prone to relapse following fixed orthodontic treatment for the same.10,11
Egermark-Ericksson et al12 found that functional malocclusion due to occlusal interferences was more important than morphologic malocclusion in the etiology of mandibular dysfunction. It has been also documented that patients with temporo- mandibular diseases tend to have more chances of anterior open bite as compared to normal subjects. The utility of OMT in anterior open bite management is well studied. The limitation of the study is small sample size and short follow up. Large scale studies are needed to reach at more reliable and successful results.
CONCLUSION
Authors found that OMT can positively influence tongue behaviour. OMT changed tongue elevation strength, tongue posture at rest, and tongue position during swallowing of solid food.
However, large scale studies are required to substantiate the results found in this study.
REFERENCES
1. Ngan P. and Fields H.W. Open bite: a review of etiology and management. Pediatric Dentistry 1997; 19: 91–98.
2. Greenlee G.M. Huang G.J. Chen S.S.H. Chen J.D. Koepsell T. and Hujoel P. Stability of treatment for anterior open-bite malocclusion: a meta-analysis. American Journal of Orthodontics and Dentofacial Orthopedics 2011;139: 154–169.
3. Remmers D. Van’t Hullenaar R.W. Bronkhorst E.M. Bergé S.J. and Katsaros C. Treatment results and long-term stability of anterior open bite malocclusion. Orthodontics &
Craniofacial Research 2008; 11: 32–42.
4. Bondemark L. Holm A. Hansen K. Axelsson S. Mohlin B. Brattstrom V. Pauling G. and Pietila T. Long-term stability of orthodontic treatment and patient satisfaction. A systematic review. The Angle Orthodontist 2007; 77: 181–191.
5. Smithpeter J. and Covell D. Relapse of anterior open bites treated with orthodontic appliances with and without orofacial myofunctional therapy. American Journal of Orthodontics and Dentofacial Orthopedics 2010; 137: 605–614.
6. Giuntini, V., Franchi, L., Baccetti, T., Mucedero, M. and Cozza, P. Dentoskeletal changes associated with fixed and removable appliances with a crib in open-bite patients in the mixed dentition. American Journal of Orthodontics and Dentofacial Orthopedics 2008;133:
70–80.
7. Torres, F., Almeida, R.R., de Almeida, M.R., Almeida-Pedrin, R.R., Pedrin, F. and Henriques, J.F. Anterior open bite treated with a palatal crib and high-pull chin cup therapy.
A prospective randomized study. European Journal of Orthodontics 2006; 28: 610–617.
8. Van Dyck C, Dekeyser A, Vantricht E, Manders E, Goeleven A, Fieuws S, Willems G. The effect of orofacial myofunctional treatment in children with anterior open bite and tongue dysfunction: a pilot study. European journal of orthodontics. 2016 Jun 1;38(3):227-34.
9. Potter, N.L. and Short, R. Maximal tongue strength in typically developing children and adolescents. Dysphagia 2009; 24:391–397.
10. Menezes, L.M., Ritter, D.E. and Locks, A. Combining traditional techniques to correct anterior open bite and posterior cross-bite. American Journal of Orthodontics and Dentofacial Orthopedics 2013; 143: 412–420.
11. Torres, F.C., Almeida, R.R., Almeida-Pedrin, R.R., Pedrin, F. and Paranhos, L.R.
Dentoalveolar comparative study between removable and fixed cribs, associated to chincup, in anterior open bite treatment. Journal of Applied Oral Science 2012; 20: 531–537.
12. Egermark-Eriksson I, Ingervall B, Carlsson G: The dependence of mandibular dysfunction in children on functionaland morphologic malocclusion. Am J Orthod 1983; 83:187-94.
