OF THE LIP AND PALATE. By T. D. FOSTER, M.D.S., F.D.S., D.Orth.R.C.S. School of Dental Surgery, University of Birmingham

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MAXILLARY DEFORMITIES IN REPAIRED CLEFTS OF THE LIP AND PALATE By T. D. FOSTER, M.D.S., F.D.S., D.Orth.R.C.S. School of Dental Surgery, University of Birmingham IN patients with repaired clefts of the lip and palate certain deformities of the maxilla are seen to occur fairly frequently. Probably the most common of these deformities are :-- I. Medial collapse of the upper alveolar arch. 2. A disturbance in downward growth of the jaw associated with the cleft of the alveolar process and palate. 3. Maxillary retrognathism. These deformities have often been considered to be results of the operation for repair of the cleft of the lip and palate. Slaughter and Brodie (I949), Graber (I949), Jolleys (I954), and Henry (I955) all put the blame for reduction in maxillary growth largely on to operative procedures. In support of this, cleft palate patients who have had no operation performed and who have suffered no reduction in growth of the maxilla have been reported. Dunn (I952), de Jesus (I959), and Mestre et al. (I96O) have shown unoperated patients whose jaw growth they report to be normal. Similarly, collapse of the alveolar arch has been thought to be a result of operation on the palate. Dunn (I952) claimed that certain types of operation were responsible for collapse of the arch. Henry (I955) advocates the prevention of collapse by delaying the operation until the deciduous dentition has erupted, and then splinting the teeth so that collapse cannot occur. Hyslop and Wynn (x952) blame the mucoperiosteal flap repair of the palate for producing a deformed palate and dental arch, and believe in using a flap of bone from the existing hard palate to fill the palate defect and prevent distortion of the dental arches. More recently some writers have suggested that the tightness of the upper lip following lip repair is responsible for collapse of the upper alveolar arch. Pmzansky (I955) has illustrated how, following lip repair in certain patients, the ends of the alveolar processes at the margins of the cleft become drawn together under the influence of the tight upper lip, and how the lesser segment of the maxillary arch may be over-ridden by the greater segment. Pierce et al. (I955) suggest that this collapse happens at about the age of 2 years. Hagerty (I957) and Swanson (I958) both believe that collapse of the upper arch occurs after lip operation and before palate operation. On the other hand, there has been some suggestion that the cleft malformation itself may bring about the maxillary deformities in some patients, quite apart from the effects of the operation. Walker (I959) has suggested that agenesis associated with the cleft malformation may be an important factor in reducing maxillary growth. Hyslop and Wynn (I952) also believe that in patients with cleft palate the growth of the maxilla is somewhat predestined, and in support of this they quote cases where in unoperated cleft palates there are certain deformities which would readily have been attributed to operation had one been performed. I82

MAXILLARY DEFORMITIES IN REPAIRED CLEFTS OF THE LIP AND PALATE 18 3 THE INCIDENCE OF MAXILLARY DEFORMITY IN PATIENTS WITH REPAIRED CLEFT LIP AND PALATE The types of maxillary deformity which have been mentioned, i.e., the medial collapse of the arch, the deficiency in downward growth, and the maxillary retrognathism, are often seen in patients with repaired cleft palate. In order to assess their incidence, and to try to come to some conclusion as to their mode of occurrence and the part played by the operation and the cleft malformation, a series of 2oo patients with repaired cleft lip and/or palate of all types was studied. The ages of the patients ranged from 6 to 23 years. The findings can be discussed under three headings. FIG. I Models of the upper dentition in patients with repaired cleft palate. Above, left, showing the " pre-operative" type of collapse in a patient with unilateral complete cleft of lip and palate. Above, right, showing bilateral "preoperative" type of collapse in a patient with bilateral complete cleft. Below, showing " buckling " type of collapse in a patient with unilateral complete cleft. I. Medial Collapse of the Upper Alveolar Areh.--Two distinct types of collapse of the upper arch were found, and they may be described as the "pre-operative " type and the "buckling " type of collapse. "Pre-operative" Type of Collapse.--The pre-operative type of collapse is the one which is most commonly described. In a unilateral complete cleft of lip and palate, the cleft divides the alveolar process into a greater and a lesser segment. In a bilateral cleft, the cleft divides the premaxilla from the two maxillary elements. The type of collapse which more usually occurs is, in a unilateral complete cleft, a medial collapse of the lesser segment behind the greater segment, and in a bilateral cleft a medial collapse of the maxillary elements behind the premaxilla, as shown in Fig. I.

18 4 BRITISH JOURNAL OF PLASTIC SURGERY This type of collapse is designated "pre-operative" because it or its precursoral condition can sometimes be seen in the infant with cleft lip and palate at a very early age, before any operation on the lip and palate has been performed (Fig. 2). FIG. 2 Models of four patients with unilateral and bilateral clefts of lip and palate, illustrating unilateral and bilateral " pre-operative " type of collapse, and showing how the ultimate collapse (below) could easily have resulted from the pre-operative condition (above). Suggested Mode of Occurrence of "Pre-operative " Collapse.mIt is suggested that "pre-operative" type of collapse of the arch occurs under the influence of the following factors. This is illustrated diagrammatically in Fig. 3. Pre-operative Stage-- I. Forward growth of the nasal septum. 2. Pressure from buccal musculature. 3- Presence of defect in bony palate. Post-operative Stage-- 4. Tension of lip and cheek following lip repair. 5. Possible tension in palate following palate repair. Pre-operative Stage.--Under the influence of the forward growth of the nasal septum the premaxillary part of the upper jaw is carried forwards. This is most strikingly seen in some patients with complete bilateral cleft of the lip and palate, where the premaxilla is completely detached from the maxillary elements, but can be seen to a lesser extent in a complete unilateral cleft of lip and palate where the premaxilla on one side is separated from the maxilla and is rotated forwards from the maxillary element on that side. In a unilateral cleft, this forward growth of the premaxillary element allows the lesser segment to move medially under the influence of the pressure from the cheek, and this is facilitated by the fact that

MAXILLARY DEFORMITIES IN REPAIRED CLEPTS OF THE LIP AND PALATE I8 5- there is a complete cleft through the bony palate on that side. In a bilateral cleft, both maxillary segments would move medially under the same conditions. Post-operative Stage.--After the operation for closure of the lip cleft the repaired muscles of the upper lip apply constant tension to the upper alveolar arch. ~ NRSRL5EPT~L (,ROWTH. This T NRSBLSEPTRL. (;ROWTH. PRES~,URE FROM A B FIG. 3 Diagram to illustrate the suggested mode of occurrence of the " pre-operative" type of collapse of the upper arch. has the effect of moving back the premaxillary element so that it impacts against the already collapsed maxillary segment. It may also increase the degree of medial collapse of the maxillary segment. Following repair of the palate cleft it is possible that tension from the palate may further increase the collapse of the maxillary segment, as suggested by some writers.

I86 BRITISH JOURNAL OF PLASTIC SURGERY This suggestion that collapse of the arch of this pre-operafive type can occur quite independently of the operation on the lip or palate receives support from reports by Davis (i95 I) of a patient aged 49 and by Glass (I956) of a patient aged I5, both with bilateral complete cleft of lip and palate, who had had neither lip nor palate repair and who exhibited typical "pre-operative" collapse of the arches, "Buckling" Type of Collapse of the Arch.--The " buckling" type of collapse (see Fig. I), as it may conveniently be called, is quite different from the "pre-operative" type of collapse, and occurs much less commonly. As shown in Fig. i, it is a "buckling" of the alveolar arch so that the premolar regions are distorted medially. It seems to be always bilateral, even in a unilateral cleft palate. Fie. 4 Models of a patient with repaired complete unilateral cleft of lip and palate, showing the progressive nature of the " buckling " type of collapse. The model on the left was made some three years before the model on the right. An increased collapse and narrowness of the arch can be seen in the later model. It is suggested here that the "buckling" type of collapse is largely the result of p.alate repair. It can be seen from the table that this type of collapse occurs in panents with cleft of the palate only. In these patients, with no lip or alveolar process deft, there is no tension from the lip and no pre-operative collapse, because the alveolar process is intact. It seems likely that any collapse occurring after palate repair in these patients is a result of tension from the palate. It is interesting to note that this type of collapse can increase even after ten or more years have elapsed since the original palate operation, as can be seen from Fig. 4. The Incidence of Collapse of the Upper Arch.--A total of I67 patients with either complete cleft of lip and palate or cleft of palate only was examined to determine the incidence of collapse of the upper arch. The results are shown in the table. It can be seen from this table that the incidence of patients with "pre-operative" type of collapse (44"9 per cent. of the total patients) was appreciably greater than that of the " buckling" type of collapse (I3"2 per cent. of the total patients), whilst only 4I "9 per cent. of the total patients had no collapse of the upper arch. The pre-operative type of collapse, which is apparently the greater problem, obviously occurs only in patients with complete cleft of lip, alveolar process, and palate. In certain cases the initial stages of this collapse have occurred before any operation is performed. In such cases, to prevent the increase in collapse

MAXILLARY DEFORMITIES IN REPAIRED CLEFTS OF THE LIP AND PALATE I8 7 which the tightness of the lip and musculature brings about following lip repair, it would seem that pre-operative realignment of the maxillary and premaxillary elements of the arch by methods such as described by Kjellgren (I949), McNeill (I954, I956), Nordin (r957), and Burston (r958) is of considerable value. TABLE Collapse of the Maxillary Arch in Different Types of Cleft Lip and Palate Cleft Lip and Palate. " Pre-operative Collapse. Colla )sed.... Buckling" Collapse. Not Collapsed. Total. Post-alveolar cleft. Complete unilateral cleft. Complete bilateral cleft o 5 r Unilateral 6 Bilateral I8 7 II II 4o I9 I8 I02 47 Totals 75 (44"9 per cent.) 22 (13"2 per cent.) 7 (4x'9 per cent.) I67 (Ioo per cent.) 2. Disturbance of the Downward Growth of the Maxilla.--It seems reasonable to expect that if some agenesis of growth occurs as a result of the cleft malformation, it would be more pronounced on the cleft side in a unilateral cleft than on the non-cleft side. Any disturbance in downward growth of the maxilla which affects one side more than the other has a marked effect on the level of the occlusal plane of the upper teeth. It was therefore decided to study the level of the upper occlusal plane in patients with repaired complete unilateral cleft of lip, alveolar process, and palate to ascertain whether any difference in level existed between the cleft and the non-cleft sides. The study was made by mounting models of the patient's upper and lower dental arches in such a way that the base of the upper model corresponded to the height and level of the Frankfort horizontal plane of the head, and the occlusal plane of the teeth showed its actual relationship to the horizontal plane (Foster, I959 a). Any deviations in the occlusal level were thus readily seen. Fig. 5 illustrates models which have been mounted in this way. Discrepancies found in the Occlusal Level.--Two types of discrepancy in the occlusal level were found :-- (a) In certain patients the occlusal plane was higher on the side where the cleft had occurred. This indicated a general lack of downward growth of the alveolar process of the maxilla on the cleft side, and is seen on the models illustrated in Fig. 5. (b) In certain other patients the occlusal level of the upper jaw was higher immediately behind the cleft, as shown in Fig. 6. The Incidence of Occlusal Plane Discrepancies.~Models of the jaws of eighty-two patients with complete unilateral cleft of lip, alveolar process, and palate were made

I88 BRITISH JOURNAL OF PLASTIC SURGERY and studied to assess the incidence of occlusal plane discrepancies. The following results were obtained :- Upper Occlusal Plane :- Level.. 27 Higher on cieft side 28 Higher immediately belaind cleft 2 7 In no patient was the occlusal plane higher on the non-cleft side than on the cleft side. As the operation on the palate can be said to affect the non-cleft side FIG. 5 Models of a patient with unilateral complete cleft of lip and palate (left) and a patient with unilateral mandibular underdevelopment (right), which have been based in such a way that the top of the upper model corresponds to the level of the Frankfort horizontal plane. The disturbance in the occlusal level is readily seen. FIG. 6 Model of the upper dental arch of a patient with unilateral complete cleft of lip and palate, showing the rise in the occlusal level immediately behind the cleft of the alveolar process. and the cleft side of the jaw more or less equally, it can be argued that this adverse effect on downward growth of the jaw which seems to occur on the cleft side only, or at least on the cleft side more than on the non-cleft side, is likely to be due to some agenesis of growth associated with the cleft malformation.

MAXILLARY DEFORMITIES IN REPAIRED CLEFTS OF THE LIP AND PALATE I8 9 3. Maxillary Retrognathism.--The examination of 200 patients with repaired cleft lip and palate in order to assess the incidence of maxillary retrognathism has been reported previously (Foster, 1959 b). It was found that about 34 per cent. of the total patients had retrognathism of the maxilla relative to the position of the mandible. In three surveys of sections of the non-deft palate population in this country, the incidence of relative maxillary retrognathism has been found to be 9 per cent. (Leech, I958), 2"7 per cent. (Pogrel, I96O), and II.I per cent. (Walther, 196o) respectively. This suggests that some factor must be present which has caused an increased incidence of maxillary retrognathism in the cleft palate patients. This factor may be the operation on the cleft, or agenesis associated with the malformation, or both. The extent of the original deformity must also be borne in mind. Some patients exhibit much more deficiency of tissue than others, and may therefore be predestined to exhibit maxillary underdevelopment. It would seem then that forward growth of the maxilla is adversely affected in some patients with repaired cleft palate. How much this is due to the operation, and how much is the result of underdevelopment associated with the cleft malformation itself, remains difficult to assess. SUMMARY AND CONCLUSIONS Three deformities of the maxilla are commonly seen in patients with repaired cleft lip and palate. These are :-- I. Medial collapse of the upper alveolar arch. 2. A disturbance in downward growth of the jaw associated with the cleft of the alveolar process and palate. 3. Maxillary retrognathism. Although these deformities have often been considered to be the results of operation for repair of the lip and palate, it is suggested here that they may be due, at least in part, to some degree of agenesis of growth associated with the deft malformation. The results of a survey of 20o patients with repaired cleft lip and palate indicate that there are two types of medial collapse of the upper alveolar arch. It is suggested that in the most common type the initial stages of collapse have occurred before any operation on the lip and palate has been performed in some cases. These are the patients who would benefit from pre-operative alignment of the maxillary arch. Simply delaying the operation for repair of the palate would not prevent collapse of the maxillary arch in these patients. In the second type of collapse of the arch, which is relatively uncommon, the main factor seems to be the palate operation. Disturbance in downward growth of the upper jaw was found in some patients with repaired cleft lip and palate, resulting, in unilateral cleft patients, in the occlusal plane of the upper teeth being higher on the side which was cleft. As the operation for repair of the cleft palate involves both sides of the palate more or less equally, this unilateral nature of the growth disturbance suggests that there is in some patients a diminution in growth potential associated with the cleft malformation, quite apart from the effects of the operation on the palate.

I90 BRITISH JOURNAL OF PLASTIC SURGERY The incidence of relative maxillary retrognathism is appreciably greater among patients with repaired cleft lip and palate than among the non-cleft palate population. It remains difficult to assess how much this is due to the operations for repair of the cleft lip and palate and how much to agenesis of growth associated with the cleft malformation. I woum like to express my thanks to Dr D. Greet Walker and to members of the Plastic Surgery Unit, Stoke Mandeville Hospital, for their help in this study. I also wish to acknowledge a generous grant from Ethieon Ltd., of Edinburgh, and the help of the Oxford Regional Hospital Board, which made this work possible. REFERENCES BORSTON, W. R. (1958). Dent. Practit., 9, 41. DAVIS, A. D. (1951). Plast. reconstr. Surg., 7, 482. DUNN, F. S. (1952). Plast. reconstr. Surg., 9, lo8. FOSTER, T. D. (1959 a). ft. Pros. Dent., 9, 717. -- (1959 b). Trans. int. Soc. plast. Surg., p. 36. GLASS, D. F. (1956). Trans. Europ. Orthodont. Soc., 32, 249. GRABER, T. M. (1949). Surg. Gynec. Obstet., 88, 359- I-IA~ERTY, R. L. (1957). Angle Orthodont., 27, I. HENRY, T. C. (1955). Trans. Europ. Orthodont. Soc., 3I, 31o. HX'SLOP, V. B., and WYNN, S. K. (1952). Plast. reconstr. Surg., 9, 97. DE JESUS, J. (1959). Amer. ft. Orthodont., 45, 61. JOLLEYS, A. (1954)- Brit. ft. plast. Surg., 7, 229. KJELLGm~N, B. (1949). Trans. Europ. Orthodont. Soe., 26, 164. LEECH, H. L. (1958). Dent. Practit., 9, 57. McNEIL, C. K. (1954). " Oral and Facial Deformity." London : Pitman. -- (1956). Brit. dent. ft., IOI, 191. MESTRE, J., DE JESUS, J., and SUBTELNY, J. D. (196o). Angle Orthodont., 30, 78. NORDIN, K. E. (1957). Trans. Europ. Orthodont. Soc., 33, 333. PIERCE, G. W., TERWlLLIGER, K. F., PENNISI, V., and KLABUNDE, E. H. (1955). Plast. reconstr. Surg., x6, 3. POGREL, H. (196o). Brit. dent. ft., lo8, 225. PRUZANSKY, S. (1955). Amer. ft. Orthodont., 4x, 827. SLAUGHTER, W. B., and BRODIE, A. G. (I949). Plast. reconstr. Surg., 4, 3II. SWANSON, L. T. (1958). Amer. ft. Surg., 96, 823. WALKER, D. G. (1959). Trans. int. Soc. plast. Surg., p. 40. WALTHER, D. P. (196o). Dent. Practit., xo, 139.