Mandibular vestibuloplasty using a free mucosal graft

Int. J. Oral Surg, 1985: 14: 11-15 (Key words: oestibuloplasty; grafts, mucosal; surgery, preprosthetlc)

Mandibular vestibuloplasty using a free mucosal graft A 2-7 year evaluation TOINE 1. M. HUYBERS, PAUL J. W. STOELINGA, HANS A. DE KOOMEN AND HENK TIDEMAN

Departments of Maxillofacial Prosthodontics and Oral and Maxillofacial Surgery, Municipal Hospital, Arnhem, The Netherlands ABSTRACT - A long-term follow-up (7-2 years) of 152 patients who underwent a vestibuloplasty is presented. Special emphasis has been put on the condition of the graft, nerve disturbances and chin contour changes. As a result of this study, a mandibular vestibuloplasty procedure is recommended that has minimal side effects, and yet provides an adequate base on which to build a denture on.

(Receivedfor publication 1 August 1983, accepted 29 February 1984)

In a study of 87 patients who underwent a vestibuloplasty of the mandible using a free mucosal graft, DE KOOMEN 6 reported that in 58% of the patients, a disturbance of the sensibility of the lip and/or chin remained after 1 to 3 years. In 47% of the patients, a deep submental fold was seen, which gave the impression of a sagging chin, in several of them. The mucosal graft was found to be tightly adherent to the periosteum in 66%, whereas in 34% of cases, the graft was somewhat oedemateus and mobile. Yet, 76% of the patients considered their operation to be successful. This high figure very likely also reflects the high quality of the post-operative prosthetic treatment. In this study, the results of a long-term

follow-up (7 years) on the same group of patients will be presented. Since the initial results of this group of patients were not considered to be fully satisfactory, the operative technique was modified in order to minimize the risk of nerve disturbances and to avoid the creation of a sagging chin. A group of 65 patients who underwent a vestibuloplasty using this modified technique has also been included in this followup study.

Material and methods The 87 patients of the first group were operated according to the technique described by TIDEMANs. In 45 patients, the vestibuloplasty was

12

HUYBERS, STOELINGA, DE KOOMEN AND TIDEMAN

combined with a deepening of the floor of the mouth as described by TRAUNER & OBWEGESER 9 ; however, no grafts were used to cover the lingual periosteum. 7 to 8 years later, these patients were seen again by 2 prosthodontists (T.R. and H. de K.). The condition of the graft was evaluated as well as the functioning of the dentures. The changes in the pattern of nerve disturbances were noted. The second group of 65 patients has been divided into 2 subgroups. One group of 40 patients underwent vestibuloplasties more than 4 years ago. The second group of 25 patients has been followed at least 2 years. Care was taken in both subgroups not to extend the vestibuloplasty posterior to the mental foramen. The nerve was therefore not dissected free, nor was the supraperiosteal dissection carried all the way to the inferior border to the mandible. Approximately 5 mm of muscular tissue was left attached to the vestibular periosteum, thus reducing maximum height that could have been gained by this procedure (Fig. 1). In order to achieve better adhesion of the mucosal grafts, special consideration was given to thinning of the lamina propria; an effort was made to excise as much of the lamina propria of the mucosal graft as possible. The graft was then maximally stretched and sutured in place (Fig. 2). A stent was made to maintain the depth of the vestible and graft contact with the periosteum during the healing phase and was left in place for 7 days. In cases where a deepening of the floor of the mouth was indicated, the method as described by

BROWN 2

and DOWNTON 3 was chosen. In cases where the genioglossus muscle was prominent, a local incision lingual to the alveolar process was made in order to partially detach the muscle and eliminate the genial tubercle. The mucosa in that limited area was then repositioned inferiorly with 2 2 x 0 silk matress sutures, allowing the exposed lingual area to heal by secondary intention. This group of patients was evaluated by the same 2 prosthodontists with regard to denture functioning, condition of the graft, nerve disturbances and changes in chin contour. The neurosensory examination in both groups of patients consisted of pin-touch detection, heat and cold detection and brush directional sensitivity testing.

Results The condition of the mucosal graft after 6 to 8 years was considered to be tight and adherent in only 27% of the original group (Fig. 3). In the second and third group of 40 and 25 patients, respectively, the grafts were found to be much more tightly adherent to the periosteum (Fig. 3). The number of patients with disturbances in sensibility of the mental nerve had decreased considerably (Fig. 4). In most cases, the area involved was hypaesthetic and/or paraesthetic. For 9 patients (10%), this loss of sensibility

- -I Maximum

height to be gained

_____J>

mm

Fig. 2. Mucosal graft maximally stretched and Fig. 1. Diagram to illustrate the maximum height

to be gained in order to avoid a sagging chin. Approximately 5 mm of muscular tissue needs to be left attached to the vestibular periosteum.

sutured in place with a running 5 x 0 silk suture to the free margin of the buccal mucosa (arrows). Interrupted sutures are used to attach the graft to the top of the ridge.

VESTIBULOPLASTY WITH MUCOSAL GRAFTS TEXTURE OF MUCOSAL GRAfT

medematous aspects: 100

% 80 60 40

13

sider their surgery less successful because of this unesthetic side effect. In order to correct undesirable changes in vertical dimension, as well as to improve retention and stability, several relinings had to be carried out. An average of one relining in 1.6 years was performed.

27% First group n-S7

20

Discussion 3

7

Yearspool-up.

3. Graphicrepresentation ofthe condition of the musosal graft in the 3 different groups.

Fig.

in the lip or chin was reason enough to consider the surgery a failure, even though the functioning of the denture had improved. In the second and third groups, the immediate post-operative incidence of dyssensation is lower. Furthermore, it even improved over the years (Fig. 4). From the 65 patients of the second and third groups, only 3, in retrospect, would not have undergone their surgery because of this inconvenience. A more-or-less severe degree of sagging chin was seen in more than 50% of the first group of patients (DE KOOMEN 6 ) . In the second and third groups together, 7 patients (11%) were judged to have some form of sagging chin. These patients tended to con-

INCIDENCE OF SENSIBILITY DISTURBANCES 100 91%

% 80

60 40

31%

First group n·B7

20 ThIrdgroup n-25

1

2

3

4

5

6

7

Yearspost-ep.

Graphic representation of the improvement of sensibility disturbances over the yearsin the 3 different groups. Fig. 4.

Even though vestibuloplasties and floor of the mouth procedures are frequently performed all over the world, very few longterm follow-up studies are available to evaluate the results", Surgeons still tend to extend the denture-bearing area as far as they possibly can in their desire to meet the demands of prosthodontists. By doing so, they inevitably introduce side-effectssuch as sagging chins and nerve disturbances that obviously will decrease the patients' satisfaction with the results. It is not unreasonable to assume that preprosthetic surgery is far from popular in some prosthodontic circles because of these negative effects. Patients are much more inclined to talk with the prosthodontist than the surgeon about their inconveniences caused by surgery. On the other hand, prosthodontists have never outlined their minimum requirements in relation to sulcus depth and areas of potential flange extention, necessary for them to fabricate a denture, which will function well. More than 10 years of close cooperation between our surgical and prosthodontic departments has caused us to change our concepts of preprosthetic surgery substantially. With regard to vestibuloplasties and deepening of the floor of the mouth, a procedure has evolved that causes minimal side-effects and yet provides a sufficient base on which to build a denture. The reasoning for this may be summarized as follows: (i) The classic lowering of the floor of the mouth according to TRAUNER-OBWEGESER 9 ,

14

HUYBERS, STOELINGA, DE KOOMEN AND TIDEMAN

in which the mylohyoid muscle is detached from its ridge, gives excellent results in relation to lingual sulcus depth. However, the morbidity associated with this procedure compared to the BROWN2-DoWNTON 3 method, is fairly high. The profusely bleeding mylohoid muscle occasionally gives rise to considerable swelling in the floor of the mouth. In other cases, frank arterial bleeding that is hard to control because of retraction of the vessels to the muscles may give rise to a dangerously swollen tongue and floor of the mouth, necessitating prolonged intubation or even tracheotomy. In our experience with over 200 floor-of-the-mouth procedures, this has happened 3 times and at least 2 additional cases have been reported":". The BROWN 2-DoWNTON3 procedure gives less sulcus depth, but is much less likely to endanger the airway, and it may easily be carried out under local anaesthesia. (ii) The present study provides ample evidence that limitation of the vestibulopIasty to the area between the mental nerves diminishes the number of nerve disturbances to an acceptable figure. Even though it appears that over the years the areas of disturbed sensation become fewer and smaller, the high % found in the first group can hardly be accepted for elective surgery. Furthermore, it is possible that the continuing improvement illustrated in Fig. 4, at least in part, reflects an adaptation to, rather than a recovery from, altered sensation. (iii) The sagging chin phenomenon may be avoided by leaving part of the mentalis muscle attached to the symphysis. Nevertheless, on some occasions, inadvertant dissection of too many muscle fibers has led to a sagging chin. In order to eliminate that possibility, we recommend terminating the dissection 5 mm above the inferior border of the mandible. One should keep in mind, however, that some changes in contour of the lip and chin are unavoidable", The prosthetic implications of the limited

vestibuloplasty and the BROWN 2-DoWNmethod of lowering of the floor of the mouth are clear. This combination provides less surface for the denture base than a vestibuloplasty that reaches from one retromolar pad to the other. Furthermore, the lingual flanges of the denture cannot be extended as far as in the TRAUNER-OBWEGESER9 floor-of-the-mouth procedure. However, the gain in height of the buccal vestibule between the mental foramina and the increase in depth of the lingual sulci in the mylohyoid region provides enough space to manufacture a stable denture with sufficient retention. The extension of the denture in these areas results in a fairly characteristic shape of the denture (Fig. 5). In none of the 65 patients treated as described was it found that the base for the denture was inadequate. It is not our intention in this article to discuss the relative advantages and disadvantages of skin or mucosal grafts. The authors have wide experience with both types, and believe that whether one uses skin or mucosa" is probably of little importance for the functioning of the denture. It is therefore merely a matter of personal preference. With either, however, the continuTON 3

Fig. 5. Lower denture to show the 3 areas where

the flanges could be extended as a result of the limited vestibuloplasty and floor-of-the-mouth procedure (arrows).

VESTIBULOPLASTY WITH MUCOSAL GRAFTS

15

grafts, however, may easily be corrected by a simple procedure as depicted in Fig. 6.

References 1. ADAWY, A. M., HJ0RTING-HANSEN, E. & HIL-

Fig. 6. (A) Oedematous aspect of the graft is readily shown by "pinching" the mucosal graft. (B) Simple correction may be achieved by incision on the top of the crest and submucosal thinning of the area involved, and reduction of the redundant tissue.

ing resorption of the mandible affects the graft. The graft becomes too wide for the area covered, which results in a wrinkled skin graft or a movable and oedemateus mucosal graft (Fig. 6). In the latter case, the thickness of the lamina propria of the original mucosal graft also seems to playa role. Better results have been achieved in the 65 patients in which more attention was given to thinning the graft. Whether this improvement will persist over a longer period of time remains to be seen. Mucosal

LERUP, S.: Postoperative changes of the soft tissue profile after mandibular vestibulolingual sulcoplasty with free skin grafting. J. Oral Maxillofac. Surg: 1983: 41: 111-115. 2. BROWN, L. J.: A surgical solution to a lower denture problem. Br. Dent. J. 1953: 95: 215216. 3. DOWNTON, D.: Mylohyoid ridge resection. Dent. Rec. 1953: 74: 212-214. 4. HJ0RTING-HANSEN, E., ADAWY, A. M. & HILLERUP, S.: Mandibular vestibulolingual sulcoplasty with free skingraft: a 5-year clinical follow-up study. J. Oral Maxillofac. Surg. 1983: 41: 173-176. 5. HULL, M.: Life-threatening swelling after mandibular vestibuloplasty. J. Oral Surg. 1977: 35: 511. 6. KOOMEN, DE, H. A.: A prosthetic view on vestibuloplasty with free mucosal graft. Int. J. Oral Surg. 1977: 6: 38-41. 7. POPOWICH, L. & SAMIT, A.: Respiratory obstruction following vestibuloplasty and lowering of the floor of the mouth. J. Oral Maxillofac. Surg. 1983: 41: 255-257. 8. TIDEMAN, H.: A technique of vestibular plasty using a free mucosal graft from the cheek. Int. J. Oral Surg. 1972: 1: 76-80. 9. TRAUNER-OBWEGESER, H.: Eine modification der lingualen alveolar kammplastik nach R. Trauner. Schweiz. M. Schr. Zahnheilk. 1953: 63: 788-799. Address: P. J. W. Stoelinga Department oj Oral and Maxillofacial Surgery Gemeente Zilkenhuis Wagnerlaan 55 6800 E E Arnhem The Netherlands