- Email: [email protected]
Indications for reduction of tongue in surgical treatment of mandibular prognathism
Int. J. Oral Surg. 1976: 5:107-110 (Key words: surgery, oral; tongue; prognathism, mandibular; osteotomy)
Indications for reduction of tongue in surgical treatment of mandibular prognathism J. I, ]'. F, V E R M E E R E N
Department of Oral and Jaw Surgery, Ignatius Hospital, Breda, Holland
The literature suggests that the tongue plays an important role in the recurrence after operative correction of mandibular prognathism. To prevent such a recidivism a reductiou of tongue can be considered. However, it is difficult to decide how the tongue is involved. Size, strength and function are difficult to measure, and the literature on this subject is not concerned with these properties. A number of methods are given with which an impression can be acquired about the above-mentioned properties of the tongue. Special attention is paid to the type of the ostectomy, and the arguments for this procedure are exemplified by the investigation of 75 patients in whom a surgical correction of mandibular prognathism was performed. It is concluded that tongue reduction is more readily ind~ cated preparatory to correction of mandibular prognathism by a modified K61e procedure than before correction by means of a stepped ostectomy or an Obwegeser-Dal Pont procedure. ABSTRACT
-
-
(Received for publication 11 November 1975, accepted 5 January 1976)
Three indications for reduction of tongue volume can be found in the literature: 1. To support orthodontic treatment of abnormalities in which the tongue possibly plays a role in the pathogenesis~, 4,10. 2. Partial glossectomy has also been suggested preparatory to surgical treatment of dysgnathic disorders, especially mandibular prognathism, open bite, and bimaxillary protrusion1-8, ~, 7, o,3. Reduction of tongue volume is also indicated in cases of macroglossia due to a tumor of the tongue, e.g. a hemangioma or lymphangiomaS,10. In these cases it is often impossible to remove the entire tumor and thus partial glossectomy must suffice.
A n important consideration in the evaluation of indications is that reduction of tongue volume entails reduction of the muscular pressure exerted on adjacent structures. This is significant because the tongue is believed to play an important role in the pathogenesis, continuation, and relapse of dysgnathie disorders. BECKER8 attaches great importance to the tongue for the growth of the corpus and the capitulum of the mandible, and holds that prognathism is largely caused by macroglossia. However, other authors believe that the influence of the tongue on mandibular growth is minimal 4. This controversy is' probably explained
108
VERMEEREN
by the fact that it is virtually impossible to establish objectively to what extent tongue volume, function, and position are important in the pathogenesis of dysgnathic disorders, o r are a consequence of these disorders. I n other words, does the tongue contribute to the pathogenesis of dysgnathic disorders, or has it developed as it has because dysgnathic disorders were present? An additional difficulty is that, even given an undisturbed intermaxillary relation, it is difficult to measure and quantify tongue volume and function. A reproducible method has been described4 in which the volume of the excised tongue fragment was compared with the loss of space in the floor of the m o u t h after an operation to correct mandibular prognathism. The tongue fragment volume was measured by immersing it in water in a graduate. The loss of space in the oral floor was measured by determining the volume of the plaster mould before and after the operation (again with the aid of the amount of water which could be p o u r e d into the mould). It was thus found that the loss of space in the floor of the mouth exceeded the volume of the excised tongue fragment. This supports the idea that the tongue plays a role in relapse following operative correction of mandibular prognathism. R E I C H E N B A C H 8 and KORKHAUS 6 even went so far as to maintain that the tongue must be held almost exclusively responsible for this. SrcmF.-rst~, on the other hand, studied the position of the tongue before and after correction o f mandibular prognathism and concluded from the changes in the position of the tongue and the interval until the relapse that the tongue could hardly be held responsible. After review of the literature and from personal observations a number of factors were determined which should be taken into consideration when determining indications for tongue reduction.
1. The size of the tongue A n impression of tongue size can be gained by clinical examination. Consistency and mobility can be assessed. If, when the t o n g u e is in maximum protrusion, the tip extends past the mental pliea while at the same time the lateral edges touch the corners of the mouth, then the tongue can be regarded as enlarged 6. In the case of macroglossia, moreover, dental impressions are believed to be visible in the edges of the tongues, 10. 2. Mobility and use of the tongue The mobility of the tongue during swallowing and speech can be studied b y radiocinematography. This gives a good i m p r e s sion of tongue movements and possible abnormal habits such as tongue c o m p r e s s i o n . Logopedic examination can give information on abnormal habits such as sigmatism. 3. The strength of the tongue This can be studied by e l e c t r o m y o g r a p h i c examination of the tongue muscles. T h e r e is a linear relationship between electrical activity and the degree of contraction o f a muscle. The action potentials can supply information on the strength of a muscle. The practical procedure is very c o m p l i c a t e d due to the large n u m b e r of muscles, and the interpretation of results is difficult. It remains to be seen whether the d a t a thus obtained are "useful" in this context. 4. The type of dysgnathic disorder Clinical examination. In the l i t e r a t u r e it is stated that the tongue plays a role p a r t i c ularly in open bite, alone or c o m b i n e d with dental protrusion ~, and w h e n t h e r e are diastemas between the frontal t e e t h 10. Cephalometric examination. By c e p h a l o metric analysis the a b n o r m a l i t y c a n be characterized as dental, d e n t o a l v e o l a r , and/or skeletal. The role of the t o n g u e is
109
T O N G U E R E D U C T I O N IN PROGNATISM
1234-
M. digastricus M. mylohyoideus M. genioglossus Hyoid bone
Fig. 2. Osteotomy by a modified KSle procedure.
Fig. 1. Stepped ostectomy in the corpus mandibulae.
p r o b a b l y most important in dental or dentoalveolar protrusion in the mandible. F r o m personal observation, we w o u l d also add the type of' operation used to correct mandibular prognathism.
KSle procedure (Fig. 2). Fairly shortly after removal of the fixation device (which had been in situ for 8 weeks), six patients showed spacing between the teeth in the anterior region of the mandible. Cephalometric analysis revealed that some slight dentaI protrusion had also occurred. This abnormality was not conspicuous, however, and necessitated subsequent tongue reduction in only two cases. No further progression of spacing or of dental protrusion was observed after this intervention. In five patients the tongue had been considered too large and reduction had been carried out prior to the ostectomy. The results for all patients are listed in Table 1,
Material and methods ONLAND & MERKX7 made a follow-up study of 41 patients in whom mandibular prognathism had been corrected by a stepped ostectomy in the corpus mandibulae (Fig. 1). No relapse was observed in this series. Special attention was paid to the development of dentoalveolar protrusion and spacing between the frontal teeth. The follow-up examinations were made at least 18 months after removal of the fixation device, In six patients the tongue had been judged large or enlarged on the basis of the criteria already mentioned, and tongue reduction had been carried out prior to the operation for prognathism, In 34 other patients the mandibular prognathism had been corrected by a modified
Table 1. Number of patients, therapy and results Type of operation
Number of patients Preceding tongue reduction Subsequent tongue reduction Spacing and dental protrusion
Stepped ostectomy
Modified KSle procedure
41
34
6
5
-
2
-
6
110
VERMEEREN
Discussion
References
It remains difficult t o decide whether tongue reduction is indicated prior to surgical correction of a dysgnathic disorder. However, it is plausible that, with the second operative procedure, the tongue must be held responsible f o r the spacing and the dental protrusion. In these eases the base of the mandible is left intact and only the alveolar process is displaced in a dorsal direction (Fig. 2). The musculature of the floor o f the mouth remains largely in the same position. The tongue, too, remains in place and, after the ostectomy, it occupies considerably less space in the anterior part of the mouth. Consequently the pressure on the anterior teeth increases, and this can l e a d to spacing and protrusion of the anterior mandibular teeth. In the case of a stepped ostectomy, the entire frontal portion of the mandible, ineluding the caudal edge, is displaced in distal direction. M u c h o f the musculature of the floor of the mouth, including the tongue, is displaced in a dorsal direction. Consequently the space available to the tongue is only slightly reduced. After 6 months the dorsal displacement of the tongue was found to have diminished, but the preoperative position could no longer be attaineda~. On the basis of the above theory and results it is reasonable to assume that if a mandibular prognathism is corrected by a operative procedure in the ascending ramus (Obwegeser-Dal Pont), the findings will not essentially differ from the stepped procedure. Also, in these cases the base of the mandible, including the musculature of the floor of the mouth, is moved in a dorsal direction. There is therefore only a slight reduction in the space available to the tongue and thus no considerable increase in pressure on the anterior teeth.
L B~cK~, R.: Die Zunge als Faktor des Sagittale Unterkieferwachstums. Fortschr. Kie/erorthop. 1960: 21: 422-425. 2. BECKER, R.: Ergebnisse bei der Behandlung der Progenie und des offenen Bisses bei gleichzeitlger Zungenverkleinerung. Dtsch. Zahnaerztl. Z. 1962: 13: 892-902. 3. BECKER, R.: Die Zungenverkleinerung zur UnterstiJtzung der K.ieferorthopiidischen Behandlung. Dtsch. Zahn-, Mund-, Kie/erheilkd. 1966: 46: 210-219. 4. EGY~DI, P. & OBWEGESER, H.: Zur operativen Zungenverkleinerung. Dtsch. Zahn-, Mund-, Kieferheilkd. 1964: 41: 16-25. 5. Krrm, H.: Ergebnisse, Erfahrungen und Probleme zur operativen I~ehandlung der Progenie. Dtsch. Zahn-, Mund-, Kieferheilkd. 1963: 40: 177-216. 6. KOl~rlAUS, G.: Fortschr. Kiefer-, Geslchtschit. Bd. 4. Georg Thieme, Stuttgart, 1958. 7. ONLAND, J. M. & MEaxx, C. A.: Over de chirurgische behandeling van de mandibulaire prognathie. Ned. Ti]dschr. Tandheelkd. 1972: 79: 1-20. 8. REICI-I-~BACH, E.: Fortschr. KieJer- und Gesichtschir. Bd. 1. Georg Thieme, Stuttgait. 1955. 9. RKEINVCALD,U. Eingriff an der Zunge als Therapie yon Wachstumst~Srungen der Kiefer. Fortschr. Kie/erorthop. 1960: 21: 426-432. 10. RrlEINWALg, U.: Die Zungenverkleinerung als untersttitzende Massnahme der Progenie-Behandlung. Dtsch. Zahn-, Mttnd-, Kie/erheilkd. 1967: 49: 93-99. 11. RHEINVCXLD, U. & BECKF_at, R.: Die Beziehungen der Zunge zum normalen und gest~irten Wachstum des Unterkiefers. Fortsch. KieJerorthop. 21962: 23: 5-79. 12. SMELTS, I. H. L.: Een studie over de veranderingen in tongpositie bij geopereerde progenie patienten. Ned. Tijdschr. Tandheelkd. 1969: 76: 929-933.
Address: Dr. d. 1. J. F. Vermeeren Department of Oral and Jaw Surgery Ignatitts Ziekenhuis, Breda The Netherlands
Indications for reduction of tongue in surgical treatment of mandibular prognathism J. I, ]'. F, V E R M E E R E N
Department of Oral and Jaw Surgery, Ignatius Hospital, Breda, Holland
The literature suggests that the tongue plays an important role in the recurrence after operative correction of mandibular prognathism. To prevent such a recidivism a reductiou of tongue can be considered. However, it is difficult to decide how the tongue is involved. Size, strength and function are difficult to measure, and the literature on this subject is not concerned with these properties. A number of methods are given with which an impression can be acquired about the above-mentioned properties of the tongue. Special attention is paid to the type of the ostectomy, and the arguments for this procedure are exemplified by the investigation of 75 patients in whom a surgical correction of mandibular prognathism was performed. It is concluded that tongue reduction is more readily ind~ cated preparatory to correction of mandibular prognathism by a modified K61e procedure than before correction by means of a stepped ostectomy or an Obwegeser-Dal Pont procedure. ABSTRACT
-
-
(Received for publication 11 November 1975, accepted 5 January 1976)
Three indications for reduction of tongue volume can be found in the literature: 1. To support orthodontic treatment of abnormalities in which the tongue possibly plays a role in the pathogenesis~, 4,10. 2. Partial glossectomy has also been suggested preparatory to surgical treatment of dysgnathic disorders, especially mandibular prognathism, open bite, and bimaxillary protrusion1-8, ~, 7, o,3. Reduction of tongue volume is also indicated in cases of macroglossia due to a tumor of the tongue, e.g. a hemangioma or lymphangiomaS,10. In these cases it is often impossible to remove the entire tumor and thus partial glossectomy must suffice.
A n important consideration in the evaluation of indications is that reduction of tongue volume entails reduction of the muscular pressure exerted on adjacent structures. This is significant because the tongue is believed to play an important role in the pathogenesis, continuation, and relapse of dysgnathie disorders. BECKER8 attaches great importance to the tongue for the growth of the corpus and the capitulum of the mandible, and holds that prognathism is largely caused by macroglossia. However, other authors believe that the influence of the tongue on mandibular growth is minimal 4. This controversy is' probably explained
108
VERMEEREN
by the fact that it is virtually impossible to establish objectively to what extent tongue volume, function, and position are important in the pathogenesis of dysgnathic disorders, o r are a consequence of these disorders. I n other words, does the tongue contribute to the pathogenesis of dysgnathic disorders, or has it developed as it has because dysgnathic disorders were present? An additional difficulty is that, even given an undisturbed intermaxillary relation, it is difficult to measure and quantify tongue volume and function. A reproducible method has been described4 in which the volume of the excised tongue fragment was compared with the loss of space in the floor of the m o u t h after an operation to correct mandibular prognathism. The tongue fragment volume was measured by immersing it in water in a graduate. The loss of space in the oral floor was measured by determining the volume of the plaster mould before and after the operation (again with the aid of the amount of water which could be p o u r e d into the mould). It was thus found that the loss of space in the floor of the mouth exceeded the volume of the excised tongue fragment. This supports the idea that the tongue plays a role in relapse following operative correction of mandibular prognathism. R E I C H E N B A C H 8 and KORKHAUS 6 even went so far as to maintain that the tongue must be held almost exclusively responsible for this. SrcmF.-rst~, on the other hand, studied the position of the tongue before and after correction o f mandibular prognathism and concluded from the changes in the position of the tongue and the interval until the relapse that the tongue could hardly be held responsible. After review of the literature and from personal observations a number of factors were determined which should be taken into consideration when determining indications for tongue reduction.
1. The size of the tongue A n impression of tongue size can be gained by clinical examination. Consistency and mobility can be assessed. If, when the t o n g u e is in maximum protrusion, the tip extends past the mental pliea while at the same time the lateral edges touch the corners of the mouth, then the tongue can be regarded as enlarged 6. In the case of macroglossia, moreover, dental impressions are believed to be visible in the edges of the tongues, 10. 2. Mobility and use of the tongue The mobility of the tongue during swallowing and speech can be studied b y radiocinematography. This gives a good i m p r e s sion of tongue movements and possible abnormal habits such as tongue c o m p r e s s i o n . Logopedic examination can give information on abnormal habits such as sigmatism. 3. The strength of the tongue This can be studied by e l e c t r o m y o g r a p h i c examination of the tongue muscles. T h e r e is a linear relationship between electrical activity and the degree of contraction o f a muscle. The action potentials can supply information on the strength of a muscle. The practical procedure is very c o m p l i c a t e d due to the large n u m b e r of muscles, and the interpretation of results is difficult. It remains to be seen whether the d a t a thus obtained are "useful" in this context. 4. The type of dysgnathic disorder Clinical examination. In the l i t e r a t u r e it is stated that the tongue plays a role p a r t i c ularly in open bite, alone or c o m b i n e d with dental protrusion ~, and w h e n t h e r e are diastemas between the frontal t e e t h 10. Cephalometric examination. By c e p h a l o metric analysis the a b n o r m a l i t y c a n be characterized as dental, d e n t o a l v e o l a r , and/or skeletal. The role of the t o n g u e is
109
T O N G U E R E D U C T I O N IN PROGNATISM
1234-
M. digastricus M. mylohyoideus M. genioglossus Hyoid bone
Fig. 2. Osteotomy by a modified KSle procedure.
Fig. 1. Stepped ostectomy in the corpus mandibulae.
p r o b a b l y most important in dental or dentoalveolar protrusion in the mandible. F r o m personal observation, we w o u l d also add the type of' operation used to correct mandibular prognathism.
KSle procedure (Fig. 2). Fairly shortly after removal of the fixation device (which had been in situ for 8 weeks), six patients showed spacing between the teeth in the anterior region of the mandible. Cephalometric analysis revealed that some slight dentaI protrusion had also occurred. This abnormality was not conspicuous, however, and necessitated subsequent tongue reduction in only two cases. No further progression of spacing or of dental protrusion was observed after this intervention. In five patients the tongue had been considered too large and reduction had been carried out prior to the ostectomy. The results for all patients are listed in Table 1,
Material and methods ONLAND & MERKX7 made a follow-up study of 41 patients in whom mandibular prognathism had been corrected by a stepped ostectomy in the corpus mandibulae (Fig. 1). No relapse was observed in this series. Special attention was paid to the development of dentoalveolar protrusion and spacing between the frontal teeth. The follow-up examinations were made at least 18 months after removal of the fixation device, In six patients the tongue had been judged large or enlarged on the basis of the criteria already mentioned, and tongue reduction had been carried out prior to the operation for prognathism, In 34 other patients the mandibular prognathism had been corrected by a modified
Table 1. Number of patients, therapy and results Type of operation
Number of patients Preceding tongue reduction Subsequent tongue reduction Spacing and dental protrusion
Stepped ostectomy
Modified KSle procedure
41
34
6
5
-
2
-
6
110
VERMEEREN
Discussion
References
It remains difficult t o decide whether tongue reduction is indicated prior to surgical correction of a dysgnathic disorder. However, it is plausible that, with the second operative procedure, the tongue must be held responsible f o r the spacing and the dental protrusion. In these eases the base of the mandible is left intact and only the alveolar process is displaced in a dorsal direction (Fig. 2). The musculature of the floor o f the mouth remains largely in the same position. The tongue, too, remains in place and, after the ostectomy, it occupies considerably less space in the anterior part of the mouth. Consequently the pressure on the anterior teeth increases, and this can l e a d to spacing and protrusion of the anterior mandibular teeth. In the case of a stepped ostectomy, the entire frontal portion of the mandible, ineluding the caudal edge, is displaced in distal direction. M u c h o f the musculature of the floor of the mouth, including the tongue, is displaced in a dorsal direction. Consequently the space available to the tongue is only slightly reduced. After 6 months the dorsal displacement of the tongue was found to have diminished, but the preoperative position could no longer be attaineda~. On the basis of the above theory and results it is reasonable to assume that if a mandibular prognathism is corrected by a operative procedure in the ascending ramus (Obwegeser-Dal Pont), the findings will not essentially differ from the stepped procedure. Also, in these cases the base of the mandible, including the musculature of the floor of the mouth, is moved in a dorsal direction. There is therefore only a slight reduction in the space available to the tongue and thus no considerable increase in pressure on the anterior teeth.
L B~cK~, R.: Die Zunge als Faktor des Sagittale Unterkieferwachstums. Fortschr. Kie/erorthop. 1960: 21: 422-425. 2. BECKER, R.: Ergebnisse bei der Behandlung der Progenie und des offenen Bisses bei gleichzeitlger Zungenverkleinerung. Dtsch. Zahnaerztl. Z. 1962: 13: 892-902. 3. BECKER, R.: Die Zungenverkleinerung zur UnterstiJtzung der K.ieferorthopiidischen Behandlung. Dtsch. Zahn-, Mund-, Kie/erheilkd. 1966: 46: 210-219. 4. EGY~DI, P. & OBWEGESER, H.: Zur operativen Zungenverkleinerung. Dtsch. Zahn-, Mund-, Kieferheilkd. 1964: 41: 16-25. 5. Krrm, H.: Ergebnisse, Erfahrungen und Probleme zur operativen I~ehandlung der Progenie. Dtsch. Zahn-, Mund-, Kieferheilkd. 1963: 40: 177-216. 6. KOl~rlAUS, G.: Fortschr. Kiefer-, Geslchtschit. Bd. 4. Georg Thieme, Stuttgart, 1958. 7. ONLAND, J. M. & MEaxx, C. A.: Over de chirurgische behandeling van de mandibulaire prognathie. Ned. Ti]dschr. Tandheelkd. 1972: 79: 1-20. 8. REICI-I-~BACH, E.: Fortschr. KieJer- und Gesichtschir. Bd. 1. Georg Thieme, Stuttgait. 1955. 9. RKEINVCALD,U. Eingriff an der Zunge als Therapie yon Wachstumst~Srungen der Kiefer. Fortschr. Kie/erorthop. 1960: 21: 426-432. 10. RrlEINWALg, U.: Die Zungenverkleinerung als untersttitzende Massnahme der Progenie-Behandlung. Dtsch. Zahn-, Mttnd-, Kie/erheilkd. 1967: 49: 93-99. 11. RHEINVCXLD, U. & BECKF_at, R.: Die Beziehungen der Zunge zum normalen und gest~irten Wachstum des Unterkiefers. Fortsch. KieJerorthop. 21962: 23: 5-79. 12. SMELTS, I. H. L.: Een studie over de veranderingen in tongpositie bij geopereerde progenie patienten. Ned. Tijdschr. Tandheelkd. 1969: 76: 929-933.
Address: Dr. d. 1. J. F. Vermeeren Department of Oral and Jaw Surgery Ignatitts Ziekenhuis, Breda The Netherlands