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Studies Showing Efficacy of Orofacial Myofunctional Therapy:

I A O M | International Association of Orofacial Myology | IAOM

American Speech-Language-Hearing Association | ASHA

Smithpeter, J., and Covell, D. JR. (2010): Relapse of anterior open bites treated with orthodontic appliances with and without orofacial myofunctional therapy. American Journal of Orthodontics and Dentofacial Orthopedics, 137, 5, 605-614, 2010.

The purpose of the study was to compare the relapse rate of orthodontic appliances with and without orofacial myofunctional therapy. Results revealed: Orofacial myofunctional therapy with orthodontic treatment was efficacious in closing and maintaining closure of dental open bites in Angle Class I and Class II malocclusions, and it dramatically reduced the relapse of open bites in patients who had forward tongue posture and tongue thrust.


Moore, N.L. (2003). Suffer the little children: fixed intraoral habit appliances for treating childhood thumb sucking habits: a critical review of the literature. International Journal of Orofacial Myology, 28: 3-4.

This review of literature was written by a librarian from the United Kingdom who became concerned about the use of oral appliances for the use of various myofunctional habit patterns especially thumb sucking. His concerns motivated him to address this treatment regime through literature review, analysis and commentary. The preparation of these materials by the author presents the most extensive and comprehensive information on this topic within the past decades and beyond.


Pierce, R. (1997). The effectiveness of oral myofunctional therapy in improving patients' ability to swallow pills. International Journal of Orofacial Myology, 23:50.

Results from a review of 100 patient charts who had orofacial myology evaluation/consultation and subsequent therapy in a particular Orofacial Myologist's office for a period of 5 years revealed that 39 patients reported difficulty swallowing pills at the initial evaluation. At the conclusion of therapy all 100 patients were able to swallow pills easily at the conclusion of ten to twelve lessons of orofacial myofunctional therapy.


Ray, J. (2003). Effects of orofacial myofunctional therapy on speech intelligibility in individuals with persistent articulatory impairments. International Journal of Orofacial Myology. 29, 5-11.

This study examined the effects of orofacial myofunctional therapy (OMT) on speech intelligibility in adults with persistent articulation impairments. Six adults in the age range of 18-23 years were selected to receive OMT for a period of six weeks. Speech intelligibility increased significantly in all clients except the one diagnosed with developmental apraxia of speech. Orofacial myofunctional therapists, speech-language pathologists, and other professionals need to rule out underlying orofacial myofunctional variables when targeting speech sounds for intervention.


Andrianopoulos, M.V., and Hanson, M.L. (1987). Tongue thrust and stability of overjet correction. Angle Orthodontist, 57, 121-135.

A long-term study of incidence of tongue thrust from ages 4 to 18 found the dysfunction disappearing in some individuals and appearing in others. A small study of the effect of tongue-thrust therapy on stability of overjet correction suggested a beneficial effect. Among 34 subjects, mean age 22:

  • Orthodontic treatment alone did not eliminate tongue thrust (12 of 17 were still tongue thrusting)
  • Of 17 subjects who had received therapy, only 3 were tongue thrusting after treatment
  • Mean relapse in overjet among subjects who had received therapy: 0.56mm Among no therapy subjects: 1.94mm The difference was statistically significant
  • The results suggested that tongue thrust therapy will help in preventing overjet relapse after orthodontic treatment and that patients who have undergone therapy will tend to maintain proper tongue function


Benkert, K. (1997). The effectiveness of orofacial myofunctional therapy in improving dental occlusion. International Journal of Orofacial Myology. Vol. 23, 35-47.

The purpose of this retrospective study was to determine if dental occlusion improved when patients received orofacial myofunctional therapy. The most significant findings of this study definitively established the beneficial effect of orofacial myofunctional therapy on improving dental occlusion, decreasing dental open bite and decreasing dental overjet.


Carvalho, M.P., Sato-Tsuji, A. M., Ferreira, F.A. (1992). International Journal of Orofacial Myology. Volume XVIII, 14-20.

A prototype is presented by six orthodontists for evaluation of oral myofacial dysfunctions including oral breathing, abnormal swallowing, speech articulation errors, and chewing and sucking habits. An accurate assessment of these parameters prior to orthodontic treatment may aid in the completion and stability of orthodontic cases. The orthodontist who follows these procedures should be able to evaluate the presence or absence of facial musculature dysfunctions, and, once detected, refer the patient to a specialist such as an otolaryngologist, or certified orofacial myologist for further evaluation and more specific treatments.


Gommerman, S., Hodge, M (1995). Effects of oral myofunctional therapy on swallowing and sibilant production. The International Journal of Orofacial Myology. Vol. XXI, 9-22.

The study investigated the effectiveness of oral myofunctional therapy in eliminating a 16 year-old girl’s tongue thrust swallowing pattern and mild sibilant distortion. Oral myofunctional therapy was shown to be effective in eliminating the tongue thrust swallowing pattern of this subject, but not her sibilant distortion. However, four articulation treatment sessions were sufficient for the subject to demonstrate satisfactory sibilant production six months following treatment. It was hypothesized that oral myofunctional treatment facilitated her tongue function for accurate sibilant production.


Hahn, V., and Hahn, H. (1992). Efficacy of oral myofunctional therapy. International Journal of Orofacial Myology, 18, 21-23.

These authors contacted 131 finished cases and ninety-eight responded to the invitation to come for a post-treatment check-up. These patients were divided into three groups based on age. The results were as follows:

Group I: 6 to 10 years old: This entire group except one had learned the physiological act of swallowing by means of myofunctional therapy. The later examination showed a permanent change of the distorted pattern of swallowing in 81%. In 19%, the new swallowing pattern had not been habituated completely, i.e. not in all media. Sometimes they extended their tongues to the cup when drinking. Seventy-two percent maintained correct tongue resting position during the daytime, and in the morning upon awakening.

Group II: 12 to 16 years old: Results of this group did not differ significantly from those of Group I. The later examination showed a permanent change of the normal physiological pattern of swallowing in 83%. Seventy-one percent maintained correct tongue rest positions, day and night.

Group III: Adults: One hundred percent had normalized their patterns permanently for saliva, food and liquids. Eighty-seven percent were continuing to maintain correct tongue resting position

The comparison between the results at the end of therapy and those after several years demonstrates the necessity of a long-term surveillance of the habituation of newly learned tongue functions, breathing, and lip closure. The surveillance should continue until orthodontic treatment is finished.


Hanson, M.L. and Andrianopoulos, M.V. (1982). Tongue thrust and malocclusion. A longitudinal study. International Journal of Orthodontics, 20, 9-18.

Data was collected from a longitudinal study of tongue thrust beginning in 1967 by Hanson and associates. Data was gathered over a period of 12 3/4 years, starting with a group of 225 children with a mean age of 4 years, 9 months. Of this group, 61 were located and examined at or near age 18. The findings from this final evaluation were analyzed. Following the results of this study, these authors concluded that they were reasonably certain that orthodontic treatment does not eliminate tongue thrust with any appreciable degree of consistency. This study reported findings that demonstrate the unpredictability of tongue thrusting. Patients using the tongue in a normal manner before adolescence, or before orthodontic treatment, may develop a thrusting pattern at some time during treatment, or during adolescence. This study presents convincing evidence that the incidence of tongue thrust does not decline through adolescence, but rather increases slightly.


Harden, J., and Rydell, C.M. (1983). Effectiveness of therapy: A study of changes in swallowing habits resulting from tongue thrust therapy recommended by R.H. Barrett. International Journal of Orofacial Myology, 9, 5-11.

The purpose of this study was to (1) select from the files of R.H. Barrett subjects who had been diagnosed as manifesting tongue thrust behavior, (2) evaluate the swallowing behavior of subjects who had successfully completed therapy at least five years prior to the study, and (3) evaluate the swallowing behavior of subjects who had declined therapy at least five years prior.

Results of the study indicated that 84% of the therapy group demonstrated correct tongue function, and 100% of the individuals who had declined therapy exhibited a tongue thrust swallowing pattern. Ninety-four percent of the subjects in the therapy group typically maintained a rest posture with lips lightly closed or slightly parted and 92% appeared to have relaxed facial muscles. In contrast to this, 63.3% of the subjects in the control group held the lips apart with the tongue protruded and 70% displayed unnecessarily tense facial muscles during non-speech activities.


Haruki, T, Kishi, K. Zimmerman, J. (1999). The importance of orofacial myofunctional therapy in pediatric dentistry: Reports of two cases. Journal of Dentistry for Children, 103-107.

The purpose of this article was to evaluate cephalometric tracings regarding the impact that the cessation of thumb-sucking had on the developing dentition in two cases. Only orofacial myofunctional therapy principles were utilized to bring the thumb habit under control. In both case reports, it appeared that some of the abnormal growth tendencies were reversed by eliminating the active digit sucking habit.


Umberger, F.G., Johnston, R. (1997). The efficacy of oral myofunctional and coarticulation therapy. International Journal of Orofacial Myology, 23. 3-10.

The authors summarize the current state of knowledge about the relationships between oral myofunctional therapy and articulation therapy. They conclude that considerable evidence has been obtained that indicates that oral myofunctional therapy techniques can improve articulation of sibilant sounds.


Van Norman, Rosemarie (2001). Why we can’t afford to ignore prolonged digit sucking. Contemporary Pediatrics, Vol. 18, No. 6, 61-81.

A specialist explains the hazards of continued digit (thumb/finger) sucking habits and offers advice on breaking the habit. The article explains that children who persist in sucking a thumb or finger beyond early childhood risk significant dental problems as well as learning, speech and emotional difficulties.


Van Norman, Rosemarie: Digit-sucking: A review of the literature, clinical observations and treatment recommendations (1997). International Association of Orofacial Myology, 23, 14-35.

The purpose of this paper is to share information about the digit-(thumb/finger) sucking behavior including how it begins; the biological psychological and physiological connections; how it becomes perpetuated; problems related to prolonged sucking activity; guidelines for referral; and considerations for appropriate patient selection to enhance successful therapy.


Van Norman, Rosemarie (1985). Digit Sucking: It’s time for an attitude adjustment or rationale for the early elimination of digit-sucking habits through positive behavior modification. The International Association of Orofacial Myology, 2 (2), 14-20.

This article discusses that digit-sucking can be a significant etiological factor in atypical dental growth and development, oral-facial development, oral-facial muscle dysfunction and speech dysfunction. The technique of positive behavior modification to terminate the digit-sucking behavior has been practiced successfully by hundreds of therapists for many years.


Zimmerman, J.B. (1989). Orofacial Myofunctional therapy for bilateral tongue posture and tongue thrust associated with open bite: A case report. International Association of Orofacial Myology. Vol 15, No. 1, 5-9.

This article discusses the significance of lateral and bilateral (posterior) tongue thrust and resting posture anomalies. A case study is presented with photographic documentation of results of the coordinated efforts of the orthodontist, and the orthodontist to ensure ideal timing and coordination of intervention strategies. This case study supports the concept that orofacial myofunctional therapy can facilitate the task of the orthodontist, and contribute to orthodontic stability by creating a more favorable muscle environment for the dentition.


Yamaguchi, H. and Sebata. M (1995). Changes in oral functions and posture at rest following surgical orthodontic treatment and myofunctional therapy. International Journal of Orofacial Myology, Vol.21., 29-32.

Fifteen adult patients with skeletal mandibular prognathism or openbite underwent surgical and orthodontic treatment, and then received myofunctional therapy. The faces of fifteen adults with jaw deformities were videotaped before and after surgical orthodontic treatment and myofunctional therapy. After surgery and orthodontic treatment, improvement in occlusion and facial harmony were apparent. Study and observation of the videotape films indicated improvements in orofacial posture, muscle-tone, function in speech and swallowing and reduction of damaging muscle pressure habits.

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