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The optimal vestibuloplasty in preprosthetic surgery of the mandible
Journal of Cranio-MaxillofacialSurgery (1997) 25, 85-90 © 1997 European Association for Cranio-Maxillofacial Surgery
The optimal vestibuloplasty in preprosthetic surgery of the mandible T. Fr6schl, A. Kerscher
Department of Oral and Maxillofacial Surgery (Head" Prof. Dr Dr F Hiirle) Christian-AlbrechtsUniversity of Kiel, Germany
S U M M A R Y . Two studies (1981-1990 retrospective, and 1989-1993 prospective) were performed to determine the optimal methods in preprosthetic surgery. The first study deals with four different types of grafts (splitthickness skin, mucosal, mesh mucosal, palatal) in combination with vestibuloplasties and lowering of the floor of the mouth. The parameters, vestibular depth, mobility and resilience of the transplants were examined. Keratinized grafts (split-thickness skin and palatal) showed advantages. On the basis of a high rate of complications at the site of harvesting of palatal mucosa and the limited amount of palatal mucosa available for grafting, we prefer a split-thickness skin graft. A second prospective study to compare the EtHan- and Kazanjian-plasty showed the disadvantages of both methods. The EtHan-plasty, in combination with implants, showed a small amount of bone resorption; the Kazanjian-plasty showed a significant loss of attached mucosa. Both methods were therefore abandoned in our clinic. For cases with insufficient width of attached mucosa, we recommend a vestibuloplasty secondarily, with keratinized grafts. If there is a deep palatal vault and the need for a large amount of graft material, a split-thickness skin graft should be harvested. In cases of limited need and flat palatal vault, the graft can be harvested from the palate.
INTRODUCTION
in the past 15 years by the Department of Oral and Maxillofacial Surgery, University of Kiel. A retrospective study was performed on skin grafts in combination with mandibular vestibuloplasties and a prospective randomized study on local pedicled vestibuloplasties in combination with implants.
The majority of preprosthetic surgery procedures (56%) entail the relative augmentation of the jaw. Of these, 18.6% are vestibuloplasties of the upper jaw (Kerschbaum, 1982). Relative augmentation of the jaw includes the submucous vestibuloplasty, the vestibuloplasty with or without skin graft, and the open or closed lowering of the floor of the mouth. Since the Consensus Conference in Berlin, in 1983 (Hillerup et al., 1984; Hillerup and Terry, 1984), there is no longer a difference of opinion concerning the necessity of covering the periostium. The conference suggested covering the vestibular periostium with a skin graft and fixing the transplant with a plate. It is necessary to cover the exposed periostium because a nearly complete relapse could be proven during secondary healing with contraction and epithelialization of the vestibular periosteum. There was no consensus on preference of the type of graft. Therefore, it was necessary to examine the advantages and disadvantages of the different transplants: skin graft from the thigh, mucosal graft, meshed mucosal graft and grafts from the hard palate. As implantology gained importance, it was also necessary to examine the quality of the combination of implants and pedicled flap vestibuloplasties.
Free graft techniques
Skin and mucosal grafts are mainly used in combination with a vestibuloplasty and an open lowering of the floor of the mouth. The mucosa is incised from the left to the right molar region. The muscle fibres in the subcutaneous tissues are dissected from the periosteum and the mental nerves are spared. Only two-thirds of the mental muscles are dissected, to avoid a chin ptosis (Gonzales-Ulloa, 1972).
Split- thickness skin graft Split-thickness skin graft is harvested from the right upper thigh using a dermatome. After vestibular preparation of the periosteum, the transplant is fixed in the intraoperatively adapted splint. The transplant is thus fixed via the splint on the periosteum with circumferential sutures. The fixation is maintained for 5 days.
METHODS
Mucosal graft
The following sections deal with the indications and methods of preprosthetic surgery that have been used
The mucosal graft is harvested from the right and left inner cheeks. The graft is fixed with sutures on 85
86
Journalof Cranio-MaxillofacialSurgery
the Schuchardt sphere, a hemisphere of 10 cm diameter, with the epithelial side placed against the sphere. The submucosal fat and connective tissues are removed with scissors and tweezers.
a transplant were operated upon. Eighty-nine patients were examined in a follow-up. The vestibular depth, the mobility of the transplants and the resilience of the denture-bearing area were evaluated.
Vestibular depth Meshed mucosal graft After harvesting and thinning, the mucosal graft is meshed with the skin graft amplifier. The size of the graft can be doubled.
Palatal graft This transplant is harvested with a mucotome which was described by M6rmann and Schaer (1977). A graft is sutured onto the periosteum with resorbable sutures. Four to six strips of palatal graft have to be removed for a total vestibuloplasty. The fixation of a splint is done in the same manner as for mucosal grafts.
Pedieled flap methods Kazanjian vestibuloplasty Under local anaesthesia, an incision is made through the mucosa from one premolar region via the inner lower lip to the contralateral premolar region. The mucosa is prepared to the highest part of the alveolar crest, which is followed by epiperiosteal dissection of the mental muscles into the vestibular depth. The pedicled flap is sutured to the periosteum in the depth of the vestibulum. The wound in the vestibulum and inner lip is left to heal secondarily. This method is used with or without simultaneous insertion of implants.
The vestibular depth was measured in mm at 8 points from the right to the left molar region. The maximum vestibular depth was greater in the anterior than in the premolar or molar regions. The vestibular depth was essentially the same in all types of transplants. The new denture-bearing area was stable between 6 and 36 months postoperatively. There was no significant relapse (Fig. 1).
Resilience Resilience of the mucosa was measured with a ballpoint instrument according to Slavicek (1988) on the vestibular side of the alveolar crest, 36 months postoperatively (Table 1). The measurement of resilience showed marked differences in different types of grafts. The keratinized transplants (palatal graft, splitthickness skin graft) showed a better resilience (1 grade on average) compared to the mucosal and meshed mucosal transplants (Fig. 2).
Mobility of the transplants The mobility of the transplants was determined by a filling instrument and a special impression tray, 36 months postoperatively. The skin grafts were less mobile than the mucosal grafts. The meshed mucosal grafts were less mobile than the original mucosal grafts.
Edlan vestibuloplasty
Pedicled flaps
The standardized Edlan vestibuloplasty has gained an important role in preprosthetic surgery. An incision is made through the mucosa from one premolar region to the inner lower lip and from there to the contralateral premolar region. The mucosa is prepared to the highest point of the alveolar ridge, the periosteum is incised at the alveolar ridge and prepared under direct vision of the mental nerve down to the required vestibular depth. The periosteum is sutured to the mucosal crest of the inner lip. The pedicled mucosal flap is sutured to the periosteum in the vestibular depth. This method is mainly used in combination with the insertion of implants.
From 1989 to 1993, 40 edentulous patients underwent vestibuloplasties according to Edlan or Kazanjian, and insertion of implants in the mandibular canine region. The patients were followed up at regular intervals. Six months postoperatively, implants were exposed and the suprastructure was constructed.
Bone resorption The bone in the symphyseal area was measured on the lateral cephalogram immediately after surgery, and 6, 12 and 24 months postoperatively. The Table 1 - Resiliencegrading accordingto Slavicek
RESULTS
Free grafts From 1981 to 1989, 157 patients with lowering of the floor of mouth and mandibular vestibuloplasty with
Grade
Conditions
0 1 2 3
Tissue hard and strong Tissue similar to the attached gingiva Tissue of the densityof the soft palate Consistencyof a flabbyridge
Vestibuloplasty in preprosthetic surgery of the mandible meshed mucosal graft Localization(region)
mucosal graft Localization(region) 46
45
43
41
31
33
35
36
46
43
45
41
31
mm
palatal
45
43
36
35
36
split thickness skin graft Localization(region)
graft
41
35
mm
n=33
Localization (region) 46
33
16
16 n=30
87
33
31
35
36
46
43
45
41
31
33
/ 14 16
n=7
mm
n=19
mm
-
-
6 months
-
-
36 months
Fig. 1 - Vestibular depth after mandibular vestibulop!astywith different free graft materials 6 and 36 months postoperatively.Median of 7, 19, 30 or 33 measurements.
2
n=98
resilience
____---+ 1.5 1
1.0
0.5
0,5
[]
D
--
-[3
D
35
36
0
46
45
43
41
31
33
localization (region)
Fig. 2 - Resilience of mucosa after mandibular vestibuloplastywith different free graft materials 36 months postoperatively (grading according to Slavicek).Median of 7, 19, 30 or 33 measurements. symphyseal area immediately after surgery was set at 100% for each patient. The subsequent portion of the original symphyseal area was calculated. The symphyseal area after Kazanjian-plasty or Edlan-plasty ranged between 85 and 100%. The values for both methods overlapped considerably, even after 24 months (Fig. 3). Postoperatively, the average remaining symphyseal area was 96.4% in the Kazanjianplasties and 92.3% in the Edlan-plasties. The difference was not significant.
middle of the mandible and at the site of the implants. The measurements were performed 3, 6, 12 and 24 months postoperatively. Preoperatively, the height of the attached mucosa ranged from 0 to 2 m m in the canine region. Twenty-four months postoperatively, the height of the attached mucosa ranged between 0 and 6 m m (Fig. 4). The Edlan-plasty resulted in an increased height of attached mucosa compared with the Kazanjian-plasty. The difference was significant (P = 0.0015). Two of 20 implant sites in the Kazanjian group showed a total loss of attached mucosa.
Attached mucosa
The height of the attached gingiva was measured in the canine region preoperatively. Postoperatively, the height of the attached mucosa was measured in the
Complications The donor site on the thigh showed malpigmentation in some cases, which did not disturb any of the
. 88
Journalof Cranio-Maxillofacial Surgery area
DISCUSSION
(%)
100 95
90 85 80 75 Kazanjlan
Edlan
Fig. 3 - Bone resorption after mandibular vestibuloplasty with different pedicled flaps 24 months postoperatively. Box plot: from top to bottom, maximum 75% quartile, median 25% quartile, minimum 10 patients per group.
Table 2-Mobility of transplants (n=89, median) 36 months
postoperatively Type of transplant
Examined (n)
Mobility (ram)
Split-thickness skin graft Mucosa graft Meshed mucosa graft Palatal graft
19 7 30 38
1.3 2.5 1.9 1.3
width (ram) 6 5 4
2
........
1 0
Kazanjlan
Edlan
Fig. 4 - Attached mucosa in the region o f the implants after
mandibular vestibuloplasty with different pedicled flaps, 24 months postoperatively. Box plot: from top to bottom, maximum 75% quartile, median 25% quartile, minimum 20 sites per group.
patients. The buccal plane developed a plain starshaped scar, which in one case led to a transient impairment of mouth opening after infection. We did not see cases of candidosis in our study, regardless of the type of transplant. Two patients developed a severe complication after harvesting the complete hard palate mucosa: in both cases, periostel necrosis and osteomyelitis were observed. In one case, this led to a loss of the alveolar crest in the molar area; the other case developed a fistula into the nose.
The literature indicates continuing controversy as far as advantages and disadvantages of different types of transplants are concerned (Matras, 1968; Steinhauser, 1970; Moiler and Jolst, 1972; de Koomen et al., 1982; Hillerup 1982, 1990; Kreusch et al., 1988). We reviewed different types of transplants in a retrospective study covering 10 years. The measurements of the resilience according to Slavicek (1988), the mobility of the transplants and the vestibular sulcus depth are valuable parameters for comparison of the transplants. These parameters are not influenced subjectively by the patients. Mucosal transplants show a high degree of mobility in cases with adequate preparation of the periosteum from muscle and connective tissue at the time of operation. This mobility leads to compromise in the stability of the denture (de Koornen et al., 1982). Low mobility of the denture-bearing area allows a stable denture. Less connective tissue and thinner harvesting of the grafts explain the better resilience results (1 grade on average) of keratinized grafts. Keratinized grafts are harvested with a dermatome or mucotome in a defined thickness. They show much less subcutaneous tissue in comparison with mucosal grafts. Even with intensive thinning on the Schuchardt sphere, one does not get the direct fixation of the papillary dermal structure that can be achieved with a split skin graft. A mucosal graft cannot be fixed on the alveolar process as it can on the Schuchardt sphere. A mucosal graft shows increased resilience and mobility, especially in the lateral parts of the alveolar process. This is the reason why mucosal grafts show an increased rate of ulceration and cannot be used for prosthetic purposes (Hillerup and Terry, 1984). The judgement on sensibility is heavily influenced subjectively by the patient. It is therefore not mentioned in our study. The rate of sensory change in the region of the mental nerve is similar 3 years postoperatively in all types of transplants. The time of normalization of sensibility depends on the intensity of neurolysis (de Koomen, 1982). The reinnervation of the different types of transplants does not show any difference. The pressure sensation returns in most cases. The differentiation between sharp and blunt as well as the temperature sensation is disturbed in many cases, which corresponds to the findings of Riediger and Schwenzer (1977). Even in non-operated cases, the physiological sensation on the alveolar process has to be classified as hypaesthetic (Schriever, 1925; Strughold, 1925). This is the reason why pressure sores do not occur more often in operated than in non-operated denture-wearing patients. Only by self-examination of the denture-bearing area and regular dental check-ups can pressure sores be prevented or minimized.
Vestibuloplasty in preprosthetic surgery of the mandible
Patients require severe disability to undergo preprosthetic surgery. This group of patients can easily be approached for postoperative instructions. The subsequent sufficient cleaning of the dentures and the alveolar process might be the reason why we rarely observe mucositis. This is in contrast to observations by Hjorting-Hansen et al. (1983) and Hillerup (1987) in 25% after split-thickness skin grafts. All patients show a pigmentation disturbance at the donor site on the upper thigh after harvesting a split-thickness skin graft. On average, all patients complain about a difference in colour of the grafts, compared with the neighbouring mucosa. Especially for split skin grafts, this was described as a major disadvantage by Matras (1968). In our group of patients we had no complaints. In one case there was a functional disturbing scarring in the cheek after the harvesting of a mucosal graft. Keratinized grafts from the hard palate have the advantage of an entirely intraoral approach and minimal impairment (Goldberg et al., 1978). In our group of patients there were two severe complications, therefore we do not advise use of this donor site on a routine basis. The mandible shows a typical pattern of atrophy (Tallgren, 1972). A preprosthetic operation with exposure of the periosteum accelerates the normal /nandibular resorption (Steinhgiuser, 1971) requiring relining of the denture base at shorter intervals. It is necessary to construct dentures in correct centric occlusion and balanced articulation (Marxkors, 1980; KOrber, 1985). All types of transplants lead to a sufficient vestibular depth. Resilience and mobility are less in cases with keratinized grafts. In preprosthetic surgery, the combination of floor of mouth lowering and vestibuloplasty with split-thickness skin grafts from the thigh shows very stable results (Steinhiiuser, 1971). After vestibuloplasties, a short period of rapid bone resorption occurs (Joos and Hgirle, 1980). Subperiostal preparation in Edlan-plasty cases was followed by a considerable rate of bone resorption up to 2 years postoperatively (Hillerup et al., 1989; Brand, 1994). The prospective study of Edlan- and Kazanjianplasty does not show the high amount of bone resorption. The combination with implants might prevent progressive bone resorption (Brdnemark, 1985). Still, the Edlan-plasty is followed by a small amount of bone resorption, which is even less in the Kazanjian-plasty. On the other hand, the Kazanjian-plasty is followed by an increased loss of attached mucosa. Two of 20 implants showed a total loss of attached mucosa, necessitating a repeat vestibuloplasty. The Edlan-plasties cannot achieve the expected results. We therefore abandoned both methods in favour of a vestibuloplasty with a keratinized graft at the time of implant exposure. In consideration of
89
the donor site morbidity of palatal grafts, we use split-thickness skin grafts in cases with a deep palatal vault and the need for a large amount of graft. If there is only a small amount of transplant necessary and the palatal vault is flat, we prefer grafts from the hard palate.
References Brdnemark, P. I.: Introduction to osseointegration. In: Brgmemark, P. I., G. Zarb, T. Albrektsson (eds) Tissue-integrated prostheses. Osseointegration in clinical dentistry. Quintessenz, Berlin 1985, 11 76 Brand, G.: Die Resorption des Unterkiefers nach verschiedenen pr~prothetisch-chirurgischen Eingriffen. Eine vergleichende Untersuchung. Med. Diss, Kid (1994) Goldberg, J. S., S. S. Byers, J. DiStefano: Follow-up study of palatal graft donor sites in 24 patients. J. Oral Surg. 36 (1978) 608-609 Gonzales-'Ulloa, M.: Ptosis of the chin. J. Plast. Reconstr. Surg. 50 (1972) 54 57 Joos, U., F Harle: Die Unterkieferresorption nach Vestibulumplastik mit Mundbodensenkung. Dtsch. Zahn~irztl. Z. 35 (1980) 986-988 Hillerup, S.: Preprosthetic mandibular vestibuloplasty with buccal mucosal graft. Int. J. Oral Surg. 11 (1982) 18-88 Hillerup, S., R. Hopkins, H. A. de Koomen: Mandibular vestibuloplasty. A review of clinical follow-up. In: Stoelinga, P. J. W. (ed.) Proceedings Consensus Conference. The relative roles of vestibuloplasty and ridge augmentation in the management of the atrophic mandible. Quintessence, Chicago 1984, 59-65 Hillerup, S., B. Terry." Long-term behavior of skin and mucosal grafts in the oral cavity. In: Stoelinga, P. J. W. (ed.) Proceedings Consensus Conference. The relative roles of vestibuloplasty and ridge augmentation in the management of the atrophic mandible. Quintessence, Chicago 1984, 45-53. Hillerup, S.: Preprosthetic mandibular vestibuloplasty with split skin graft. A two-year follow-up study. Int. J. Oral Maxillofac. Surg. 16 (1987) 270-278 Hillerup, S., E. Eriksen, B. Solow: Reduction of mandibular residual ridge after vestibuloplasty. A two-year follow-up study comparing the Edlan flap, mucosal- and skin graft operations. Int. J. Oral Maxillofac. Surg. 18 (1989)271-276 Hillerup, S.: Mandibular vestibuloplasty. Experimental and clinical studies. Laegeforeningens, Kopenhagen 1990 Hjorting-Hansen, E., A. M. Adawy, S. Hillerup: Mandibular vestibulo-lingual sulcoplasty with free skin graft: A five year clinical follow-up study. J. Oral Maxillofac. Surg. 41 (1983) 173-176 Kerschbaum, Th.: Indikation und Hfiufigkceitpr~iprothetischer Eingriffe-Ergebnisse einer Umfrage Dtsch. Zahn/irztl. Z. 37 (1982) 82-87 KOrber, K.-H.: Zahn~rztliche Prothetik. Thieme, Stuttgart, 1985 de Koomen, H. A., I-£ Tideman, P. J. W. Stoelinga, A. J. M. Huyberg, F. H. J. Hendriks: Ind[kation, Technik und Ergebnisse der Unterkiefervestibulumplastik und Mundbodensenktmg. Dtsch. Zahn~irztl. Z. 37 (1982) 509-512 Kreusch, Th., R. Ewers, ,L-Th. Lambreeht: Geschlitzte Schleimhauttransplantate in der pr~iprothetischen Chirurgie. In: Watzek, G., Matejka, M. (eds). Der zahulose Unterkiefer, Seine chirurgisch-prothetische Rehabilitation. Springer, Wien 1988, 151-155 Marxkors, t~: Zusammenh~inge zwischen Okklusion totaler Prothesen und Knochenabbau. Dtsch. Zahn~irztl. Z. 35 (1980) 1036-1038 Matras, H.." Zur Anwendung der freien Schleimhauttransplantation in der pr~iprothetischen Chirurgie. Osterr. Z. Stomat. 65 (1968) 56-61 Mdrmann, W., F. P. Sehaer: Orale Schleimhautatransplantation mit dem Mukotom. Schweiz. Monatsschr. Zahnheilk. 87 (1977) 656-666 Moller, J. F , O. Jolst: A histologic follow-up study of free
90
Journal of Cranio-Maxillofacial Surgery
autogeneous skin grafts to the alveolar ridge in humans. Int. J. Oral Surg. 1 (1972) 283-289 Riediger, D., N. Schwenzer: Klinische Untersuchungen zur Reinnervation freier Hauttransplantate in der Mundh6hle. Dtsch. Z. Mund Kiefer Gesichtschir. 1 (1977) 205-209 Sehriever, H.: Die Schmerzempfindlichkeit der Mundh6hle. Z. Biol. 83 (1925) 415-434 Slavicek, R.: Personal communication ( 1988) Steinhgiuser, E. W.: 10 Jahre pr/iprothetische Chirurgie-Erfahrungen und Resultate. Dtsch. Zahngrztl. Z. 25 (1970) 113 120 Steinh~iuser, E. W.: Vestibuloplasty--skin grafts. J. Oral Surg. 29 (1971) 777-785 Strughold, H.: Die Topographie des K~tltesinnes in der Mundh6hle. Z. Biol. 83 (1925) 515-534
Tallgren, A.: The continuing reduction of the residual alveolar ridges in complete denture wearers: A mixed-longitudinal study covering 25 years. J. Prosthet. Dent. 27 (1972) 120-132 Dr Thomas Fr6sehl
Department of Oral and Maxillofacial Surgery Christian-Albrechts-University of Kiel Arnold-Heller-Str. 16 24105 Kiel Germany Paper received 14 September 1996 Accepted 28 January 1997
The optimal vestibuloplasty in preprosthetic surgery of the mandible T. Fr6schl, A. Kerscher
Department of Oral and Maxillofacial Surgery (Head" Prof. Dr Dr F Hiirle) Christian-AlbrechtsUniversity of Kiel, Germany
S U M M A R Y . Two studies (1981-1990 retrospective, and 1989-1993 prospective) were performed to determine the optimal methods in preprosthetic surgery. The first study deals with four different types of grafts (splitthickness skin, mucosal, mesh mucosal, palatal) in combination with vestibuloplasties and lowering of the floor of the mouth. The parameters, vestibular depth, mobility and resilience of the transplants were examined. Keratinized grafts (split-thickness skin and palatal) showed advantages. On the basis of a high rate of complications at the site of harvesting of palatal mucosa and the limited amount of palatal mucosa available for grafting, we prefer a split-thickness skin graft. A second prospective study to compare the EtHan- and Kazanjian-plasty showed the disadvantages of both methods. The EtHan-plasty, in combination with implants, showed a small amount of bone resorption; the Kazanjian-plasty showed a significant loss of attached mucosa. Both methods were therefore abandoned in our clinic. For cases with insufficient width of attached mucosa, we recommend a vestibuloplasty secondarily, with keratinized grafts. If there is a deep palatal vault and the need for a large amount of graft material, a split-thickness skin graft should be harvested. In cases of limited need and flat palatal vault, the graft can be harvested from the palate.
INTRODUCTION
in the past 15 years by the Department of Oral and Maxillofacial Surgery, University of Kiel. A retrospective study was performed on skin grafts in combination with mandibular vestibuloplasties and a prospective randomized study on local pedicled vestibuloplasties in combination with implants.
The majority of preprosthetic surgery procedures (56%) entail the relative augmentation of the jaw. Of these, 18.6% are vestibuloplasties of the upper jaw (Kerschbaum, 1982). Relative augmentation of the jaw includes the submucous vestibuloplasty, the vestibuloplasty with or without skin graft, and the open or closed lowering of the floor of the mouth. Since the Consensus Conference in Berlin, in 1983 (Hillerup et al., 1984; Hillerup and Terry, 1984), there is no longer a difference of opinion concerning the necessity of covering the periostium. The conference suggested covering the vestibular periostium with a skin graft and fixing the transplant with a plate. It is necessary to cover the exposed periostium because a nearly complete relapse could be proven during secondary healing with contraction and epithelialization of the vestibular periosteum. There was no consensus on preference of the type of graft. Therefore, it was necessary to examine the advantages and disadvantages of the different transplants: skin graft from the thigh, mucosal graft, meshed mucosal graft and grafts from the hard palate. As implantology gained importance, it was also necessary to examine the quality of the combination of implants and pedicled flap vestibuloplasties.
Free graft techniques
Skin and mucosal grafts are mainly used in combination with a vestibuloplasty and an open lowering of the floor of the mouth. The mucosa is incised from the left to the right molar region. The muscle fibres in the subcutaneous tissues are dissected from the periosteum and the mental nerves are spared. Only two-thirds of the mental muscles are dissected, to avoid a chin ptosis (Gonzales-Ulloa, 1972).
Split- thickness skin graft Split-thickness skin graft is harvested from the right upper thigh using a dermatome. After vestibular preparation of the periosteum, the transplant is fixed in the intraoperatively adapted splint. The transplant is thus fixed via the splint on the periosteum with circumferential sutures. The fixation is maintained for 5 days.
METHODS
Mucosal graft
The following sections deal with the indications and methods of preprosthetic surgery that have been used
The mucosal graft is harvested from the right and left inner cheeks. The graft is fixed with sutures on 85
86
Journalof Cranio-MaxillofacialSurgery
the Schuchardt sphere, a hemisphere of 10 cm diameter, with the epithelial side placed against the sphere. The submucosal fat and connective tissues are removed with scissors and tweezers.
a transplant were operated upon. Eighty-nine patients were examined in a follow-up. The vestibular depth, the mobility of the transplants and the resilience of the denture-bearing area were evaluated.
Vestibular depth Meshed mucosal graft After harvesting and thinning, the mucosal graft is meshed with the skin graft amplifier. The size of the graft can be doubled.
Palatal graft This transplant is harvested with a mucotome which was described by M6rmann and Schaer (1977). A graft is sutured onto the periosteum with resorbable sutures. Four to six strips of palatal graft have to be removed for a total vestibuloplasty. The fixation of a splint is done in the same manner as for mucosal grafts.
Pedieled flap methods Kazanjian vestibuloplasty Under local anaesthesia, an incision is made through the mucosa from one premolar region via the inner lower lip to the contralateral premolar region. The mucosa is prepared to the highest part of the alveolar crest, which is followed by epiperiosteal dissection of the mental muscles into the vestibular depth. The pedicled flap is sutured to the periosteum in the depth of the vestibulum. The wound in the vestibulum and inner lip is left to heal secondarily. This method is used with or without simultaneous insertion of implants.
The vestibular depth was measured in mm at 8 points from the right to the left molar region. The maximum vestibular depth was greater in the anterior than in the premolar or molar regions. The vestibular depth was essentially the same in all types of transplants. The new denture-bearing area was stable between 6 and 36 months postoperatively. There was no significant relapse (Fig. 1).
Resilience Resilience of the mucosa was measured with a ballpoint instrument according to Slavicek (1988) on the vestibular side of the alveolar crest, 36 months postoperatively (Table 1). The measurement of resilience showed marked differences in different types of grafts. The keratinized transplants (palatal graft, splitthickness skin graft) showed a better resilience (1 grade on average) compared to the mucosal and meshed mucosal transplants (Fig. 2).
Mobility of the transplants The mobility of the transplants was determined by a filling instrument and a special impression tray, 36 months postoperatively. The skin grafts were less mobile than the mucosal grafts. The meshed mucosal grafts were less mobile than the original mucosal grafts.
Edlan vestibuloplasty
Pedicled flaps
The standardized Edlan vestibuloplasty has gained an important role in preprosthetic surgery. An incision is made through the mucosa from one premolar region to the inner lower lip and from there to the contralateral premolar region. The mucosa is prepared to the highest point of the alveolar ridge, the periosteum is incised at the alveolar ridge and prepared under direct vision of the mental nerve down to the required vestibular depth. The periosteum is sutured to the mucosal crest of the inner lip. The pedicled mucosal flap is sutured to the periosteum in the vestibular depth. This method is mainly used in combination with the insertion of implants.
From 1989 to 1993, 40 edentulous patients underwent vestibuloplasties according to Edlan or Kazanjian, and insertion of implants in the mandibular canine region. The patients were followed up at regular intervals. Six months postoperatively, implants were exposed and the suprastructure was constructed.
Bone resorption The bone in the symphyseal area was measured on the lateral cephalogram immediately after surgery, and 6, 12 and 24 months postoperatively. The Table 1 - Resiliencegrading accordingto Slavicek
RESULTS
Free grafts From 1981 to 1989, 157 patients with lowering of the floor of mouth and mandibular vestibuloplasty with
Grade
Conditions
0 1 2 3
Tissue hard and strong Tissue similar to the attached gingiva Tissue of the densityof the soft palate Consistencyof a flabbyridge
Vestibuloplasty in preprosthetic surgery of the mandible meshed mucosal graft Localization(region)
mucosal graft Localization(region) 46
45
43
41
31
33
35
36
46
43
45
41
31
mm
palatal
45
43
36
35
36
split thickness skin graft Localization(region)
graft
41
35
mm
n=33
Localization (region) 46
33
16
16 n=30
87
33
31
35
36
46
43
45
41
31
33
/ 14 16
n=7
mm
n=19
mm
-
-
6 months
-
-
36 months
Fig. 1 - Vestibular depth after mandibular vestibulop!astywith different free graft materials 6 and 36 months postoperatively.Median of 7, 19, 30 or 33 measurements.
2
n=98
resilience
____---+ 1.5 1
1.0
0.5
0,5
[]
D
--
-[3
D
35
36
0
46
45
43
41
31
33
localization (region)
Fig. 2 - Resilience of mucosa after mandibular vestibuloplastywith different free graft materials 36 months postoperatively (grading according to Slavicek).Median of 7, 19, 30 or 33 measurements. symphyseal area immediately after surgery was set at 100% for each patient. The subsequent portion of the original symphyseal area was calculated. The symphyseal area after Kazanjian-plasty or Edlan-plasty ranged between 85 and 100%. The values for both methods overlapped considerably, even after 24 months (Fig. 3). Postoperatively, the average remaining symphyseal area was 96.4% in the Kazanjianplasties and 92.3% in the Edlan-plasties. The difference was not significant.
middle of the mandible and at the site of the implants. The measurements were performed 3, 6, 12 and 24 months postoperatively. Preoperatively, the height of the attached mucosa ranged from 0 to 2 m m in the canine region. Twenty-four months postoperatively, the height of the attached mucosa ranged between 0 and 6 m m (Fig. 4). The Edlan-plasty resulted in an increased height of attached mucosa compared with the Kazanjian-plasty. The difference was significant (P = 0.0015). Two of 20 implant sites in the Kazanjian group showed a total loss of attached mucosa.
Attached mucosa
The height of the attached gingiva was measured in the canine region preoperatively. Postoperatively, the height of the attached mucosa was measured in the
Complications The donor site on the thigh showed malpigmentation in some cases, which did not disturb any of the
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Journalof Cranio-Maxillofacial Surgery area
DISCUSSION
(%)
100 95
90 85 80 75 Kazanjlan
Edlan
Fig. 3 - Bone resorption after mandibular vestibuloplasty with different pedicled flaps 24 months postoperatively. Box plot: from top to bottom, maximum 75% quartile, median 25% quartile, minimum 10 patients per group.
Table 2-Mobility of transplants (n=89, median) 36 months
postoperatively Type of transplant
Examined (n)
Mobility (ram)
Split-thickness skin graft Mucosa graft Meshed mucosa graft Palatal graft
19 7 30 38
1.3 2.5 1.9 1.3
width (ram) 6 5 4
2
........
1 0
Kazanjlan
Edlan
Fig. 4 - Attached mucosa in the region o f the implants after
mandibular vestibuloplasty with different pedicled flaps, 24 months postoperatively. Box plot: from top to bottom, maximum 75% quartile, median 25% quartile, minimum 20 sites per group.
patients. The buccal plane developed a plain starshaped scar, which in one case led to a transient impairment of mouth opening after infection. We did not see cases of candidosis in our study, regardless of the type of transplant. Two patients developed a severe complication after harvesting the complete hard palate mucosa: in both cases, periostel necrosis and osteomyelitis were observed. In one case, this led to a loss of the alveolar crest in the molar area; the other case developed a fistula into the nose.
The literature indicates continuing controversy as far as advantages and disadvantages of different types of transplants are concerned (Matras, 1968; Steinhauser, 1970; Moiler and Jolst, 1972; de Koomen et al., 1982; Hillerup 1982, 1990; Kreusch et al., 1988). We reviewed different types of transplants in a retrospective study covering 10 years. The measurements of the resilience according to Slavicek (1988), the mobility of the transplants and the vestibular sulcus depth are valuable parameters for comparison of the transplants. These parameters are not influenced subjectively by the patients. Mucosal transplants show a high degree of mobility in cases with adequate preparation of the periosteum from muscle and connective tissue at the time of operation. This mobility leads to compromise in the stability of the denture (de Koornen et al., 1982). Low mobility of the denture-bearing area allows a stable denture. Less connective tissue and thinner harvesting of the grafts explain the better resilience results (1 grade on average) of keratinized grafts. Keratinized grafts are harvested with a dermatome or mucotome in a defined thickness. They show much less subcutaneous tissue in comparison with mucosal grafts. Even with intensive thinning on the Schuchardt sphere, one does not get the direct fixation of the papillary dermal structure that can be achieved with a split skin graft. A mucosal graft cannot be fixed on the alveolar process as it can on the Schuchardt sphere. A mucosal graft shows increased resilience and mobility, especially in the lateral parts of the alveolar process. This is the reason why mucosal grafts show an increased rate of ulceration and cannot be used for prosthetic purposes (Hillerup and Terry, 1984). The judgement on sensibility is heavily influenced subjectively by the patient. It is therefore not mentioned in our study. The rate of sensory change in the region of the mental nerve is similar 3 years postoperatively in all types of transplants. The time of normalization of sensibility depends on the intensity of neurolysis (de Koomen, 1982). The reinnervation of the different types of transplants does not show any difference. The pressure sensation returns in most cases. The differentiation between sharp and blunt as well as the temperature sensation is disturbed in many cases, which corresponds to the findings of Riediger and Schwenzer (1977). Even in non-operated cases, the physiological sensation on the alveolar process has to be classified as hypaesthetic (Schriever, 1925; Strughold, 1925). This is the reason why pressure sores do not occur more often in operated than in non-operated denture-wearing patients. Only by self-examination of the denture-bearing area and regular dental check-ups can pressure sores be prevented or minimized.
Vestibuloplasty in preprosthetic surgery of the mandible
Patients require severe disability to undergo preprosthetic surgery. This group of patients can easily be approached for postoperative instructions. The subsequent sufficient cleaning of the dentures and the alveolar process might be the reason why we rarely observe mucositis. This is in contrast to observations by Hjorting-Hansen et al. (1983) and Hillerup (1987) in 25% after split-thickness skin grafts. All patients show a pigmentation disturbance at the donor site on the upper thigh after harvesting a split-thickness skin graft. On average, all patients complain about a difference in colour of the grafts, compared with the neighbouring mucosa. Especially for split skin grafts, this was described as a major disadvantage by Matras (1968). In our group of patients we had no complaints. In one case there was a functional disturbing scarring in the cheek after the harvesting of a mucosal graft. Keratinized grafts from the hard palate have the advantage of an entirely intraoral approach and minimal impairment (Goldberg et al., 1978). In our group of patients there were two severe complications, therefore we do not advise use of this donor site on a routine basis. The mandible shows a typical pattern of atrophy (Tallgren, 1972). A preprosthetic operation with exposure of the periosteum accelerates the normal /nandibular resorption (Steinhgiuser, 1971) requiring relining of the denture base at shorter intervals. It is necessary to construct dentures in correct centric occlusion and balanced articulation (Marxkors, 1980; KOrber, 1985). All types of transplants lead to a sufficient vestibular depth. Resilience and mobility are less in cases with keratinized grafts. In preprosthetic surgery, the combination of floor of mouth lowering and vestibuloplasty with split-thickness skin grafts from the thigh shows very stable results (Steinhiiuser, 1971). After vestibuloplasties, a short period of rapid bone resorption occurs (Joos and Hgirle, 1980). Subperiostal preparation in Edlan-plasty cases was followed by a considerable rate of bone resorption up to 2 years postoperatively (Hillerup et al., 1989; Brand, 1994). The prospective study of Edlan- and Kazanjianplasty does not show the high amount of bone resorption. The combination with implants might prevent progressive bone resorption (Brdnemark, 1985). Still, the Edlan-plasty is followed by a small amount of bone resorption, which is even less in the Kazanjian-plasty. On the other hand, the Kazanjian-plasty is followed by an increased loss of attached mucosa. Two of 20 implants showed a total loss of attached mucosa, necessitating a repeat vestibuloplasty. The Edlan-plasties cannot achieve the expected results. We therefore abandoned both methods in favour of a vestibuloplasty with a keratinized graft at the time of implant exposure. In consideration of
89
the donor site morbidity of palatal grafts, we use split-thickness skin grafts in cases with a deep palatal vault and the need for a large amount of graft. If there is only a small amount of transplant necessary and the palatal vault is flat, we prefer grafts from the hard palate.
References Brdnemark, P. I.: Introduction to osseointegration. In: Brgmemark, P. I., G. Zarb, T. Albrektsson (eds) Tissue-integrated prostheses. Osseointegration in clinical dentistry. Quintessenz, Berlin 1985, 11 76 Brand, G.: Die Resorption des Unterkiefers nach verschiedenen pr~prothetisch-chirurgischen Eingriffen. Eine vergleichende Untersuchung. Med. Diss, Kid (1994) Goldberg, J. S., S. S. Byers, J. DiStefano: Follow-up study of palatal graft donor sites in 24 patients. J. Oral Surg. 36 (1978) 608-609 Gonzales-'Ulloa, M.: Ptosis of the chin. J. Plast. Reconstr. Surg. 50 (1972) 54 57 Joos, U., F Harle: Die Unterkieferresorption nach Vestibulumplastik mit Mundbodensenkung. Dtsch. Zahn~irztl. Z. 35 (1980) 986-988 Hillerup, S.: Preprosthetic mandibular vestibuloplasty with buccal mucosal graft. Int. J. Oral Surg. 11 (1982) 18-88 Hillerup, S., R. Hopkins, H. A. de Koomen: Mandibular vestibuloplasty. A review of clinical follow-up. In: Stoelinga, P. J. W. (ed.) Proceedings Consensus Conference. The relative roles of vestibuloplasty and ridge augmentation in the management of the atrophic mandible. Quintessence, Chicago 1984, 59-65 Hillerup, S., B. Terry." Long-term behavior of skin and mucosal grafts in the oral cavity. In: Stoelinga, P. J. W. (ed.) Proceedings Consensus Conference. The relative roles of vestibuloplasty and ridge augmentation in the management of the atrophic mandible. Quintessence, Chicago 1984, 45-53. Hillerup, S.: Preprosthetic mandibular vestibuloplasty with split skin graft. A two-year follow-up study. Int. J. Oral Maxillofac. Surg. 16 (1987) 270-278 Hillerup, S., E. Eriksen, B. Solow: Reduction of mandibular residual ridge after vestibuloplasty. A two-year follow-up study comparing the Edlan flap, mucosal- and skin graft operations. Int. J. Oral Maxillofac. Surg. 18 (1989)271-276 Hillerup, S.: Mandibular vestibuloplasty. Experimental and clinical studies. Laegeforeningens, Kopenhagen 1990 Hjorting-Hansen, E., A. M. Adawy, S. Hillerup: Mandibular vestibulo-lingual sulcoplasty with free skin graft: A five year clinical follow-up study. J. Oral Maxillofac. Surg. 41 (1983) 173-176 Kerschbaum, Th.: Indikation und Hfiufigkceitpr~iprothetischer Eingriffe-Ergebnisse einer Umfrage Dtsch. Zahn/irztl. Z. 37 (1982) 82-87 KOrber, K.-H.: Zahn~rztliche Prothetik. Thieme, Stuttgart, 1985 de Koomen, H. A., I-£ Tideman, P. J. W. Stoelinga, A. J. M. Huyberg, F. H. J. Hendriks: Ind[kation, Technik und Ergebnisse der Unterkiefervestibulumplastik und Mundbodensenktmg. Dtsch. Zahn~irztl. Z. 37 (1982) 509-512 Kreusch, Th., R. Ewers, ,L-Th. Lambreeht: Geschlitzte Schleimhauttransplantate in der pr~iprothetischen Chirurgie. In: Watzek, G., Matejka, M. (eds). Der zahulose Unterkiefer, Seine chirurgisch-prothetische Rehabilitation. Springer, Wien 1988, 151-155 Marxkors, t~: Zusammenh~inge zwischen Okklusion totaler Prothesen und Knochenabbau. Dtsch. Zahn~irztl. Z. 35 (1980) 1036-1038 Matras, H.." Zur Anwendung der freien Schleimhauttransplantation in der pr~iprothetischen Chirurgie. Osterr. Z. Stomat. 65 (1968) 56-61 Mdrmann, W., F. P. Sehaer: Orale Schleimhautatransplantation mit dem Mukotom. Schweiz. Monatsschr. Zahnheilk. 87 (1977) 656-666 Moller, J. F , O. Jolst: A histologic follow-up study of free
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Journal of Cranio-Maxillofacial Surgery
autogeneous skin grafts to the alveolar ridge in humans. Int. J. Oral Surg. 1 (1972) 283-289 Riediger, D., N. Schwenzer: Klinische Untersuchungen zur Reinnervation freier Hauttransplantate in der Mundh6hle. Dtsch. Z. Mund Kiefer Gesichtschir. 1 (1977) 205-209 Sehriever, H.: Die Schmerzempfindlichkeit der Mundh6hle. Z. Biol. 83 (1925) 415-434 Slavicek, R.: Personal communication ( 1988) Steinhgiuser, E. W.: 10 Jahre pr/iprothetische Chirurgie-Erfahrungen und Resultate. Dtsch. Zahngrztl. Z. 25 (1970) 113 120 Steinh~iuser, E. W.: Vestibuloplasty--skin grafts. J. Oral Surg. 29 (1971) 777-785 Strughold, H.: Die Topographie des K~tltesinnes in der Mundh6hle. Z. Biol. 83 (1925) 515-534
Tallgren, A.: The continuing reduction of the residual alveolar ridges in complete denture wearers: A mixed-longitudinal study covering 25 years. J. Prosthet. Dent. 27 (1972) 120-132 Dr Thomas Fr6sehl
Department of Oral and Maxillofacial Surgery Christian-Albrechts-University of Kiel Arnold-Heller-Str. 16 24105 Kiel Germany Paper received 14 September 1996 Accepted 28 January 1997