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Periodontal surgery related to alveolar bone reconstruction for implant insertion
15 Periodontal surgery related to alveolar bone reconstruction for implant insertion M. LECONTE, T. WOJCIK, J. FERRI, Roger Salengro University Hospital, France, M. MONGEOT, Private practice, Lille, France Abstract: The surgical augmentation of peri implant soft tissue may be beneficial insofar as it increases both the thickness and width of the keratinized attached gingiva, as well as enhancing the aesthetic outcome of implant therapy. The aim of this chapter is to describe and illustrate the treatments of four patients, in order to highlight the use of pedicled flaps, an epithelioconnective graft, and a sub-epithelial connective tissue graft in the re-establishment of normal tissue volume and contour around dental implants. Key words: implant, soft tissue grafts with dental implants, flap management with dental implants.
15.1 Introduction Considering the impact of the periodontal environment within the field of implantology, Robert James argued in 1973 that the same surgery that was used to improve the environment and vitality of a natural tooth, would also be similarly beneficial in the case of a dental implant.1 Therefore, his opinion was that both the quality and the quantity of tissues surrounding the implants were of major importance for successful implant treatment. Nevertheless, at that time, the main objective of implantologists was to obtain the osseointegration of dental implants. Nowadays, the aesthetical aspect of such treatment has become just as essential as the purely medical objectives. In this chapter, we are going to describe the optimal environment that should be present or created around an implant to optimize its durability.
15.2 Muco gingival environment around natural teeth In a healthy situation, we would expect to find a muco gingival environment around the natural teeth. It may be argued that when a rigorous control of plaque is performed, a band of keratinized gingival around the tooth does not affect the periodontal health.2 However, the presence of an aesthetical and sub-gingival prosthesis leads to an increase in dental plaque. Therefore, in such a case, some keratinized gingiva is required.3 In the event that we discover a frenum, which tends to open the sulcus and thereby allow for the development of a bacterial environment, the frenum needs to be removed and a band of attached gingiva needs to be created. 284 © Woodhead Publishing Limited, 2011
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15.3 Role of the keratinized gingiva around the implants It is necessary to distinguish between the soft tissues surrounding the implants and the periodontium. ‘Gingiva’ is the term that we use for the tissues surrounding natural teeth. However, we use the term ‘Mucosa’ to describe the tissues surrounding implants. The peri-implant mucosa is a scar tissue, fibrous, poor in cells and less vascularized than the periodontium. Compared to the periodontium, the soft tissue surrounding the implants does not show any cement, desmodontium, dentoperiostial or dento-gingival fibres. Among the specialists, some controversial approaches have been developed and some studies take the view that the attached gingiva is not an essential element in the implant protocol. Scandinavian teams do not consider the quality of the tissue surrounding the implant.4 Provided that a good oral hygiene is maintained, the absence of attached gingiva around the implant does not significantly impact upon the reliability of the peri-implant biologic seal.5,6 According to Buser, a non mobile band of tissue is essential to secure the integrity of the biological seal.7 Ouhayoun considers a large keratinized gingival band around the implants to be more favourable. In his view, this provides adequate foundations to resist mechanical influence, and also contributes to better gingival hygiene.8 A peri-implant mucosa is more likely to be affected by a mechanical injury than the gingiva, inducing a greater amount of inflammation. If there is an infragingival implant prosthesis, or if implants are close to a zone of muscular tension, management of the tissue attached around the implant restorations seems necessary. To summarize, most clinicians agree that an adequate zone of attached soft tissue, which has been intimately adapted to the emergence of the implant abutment, is necessary to ensure the long term success of the implant rehabilitation.9 Therefore, we will now describe our various management techniques, which have been adapted according to the amount of soft tissues present.
15.4 Developing a favourable environment around the implants When aiming to develop a favourable environment around the implants, there are a number of different situations that may present themselves, as follows.
15.4.1 The amount of keratinized gingiva is normal Where the amount of keratinized gingiva is normal, the soft tissues should be protected and handled with care over the course of the different steps of the treatment.
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15.4.2 The quantity of attached and keratinized gingiva is reduced There is some attached gingiva remaining at the recipient site In these cases a pedicled flap can be raised and fixed apically or laterally to the implant site.10 Case report 1 In the following case report, we can observe a view which demonstrates the high muscle attachment. A horizontal incision is made lingually or palatally in the keratinized tissue. Then two vertical incisions are made on each side of the implant, beyond the muco gingival line (Fig. 15.1). A muco periostal flap is raised in the coronal part of the implant, creating easier access to the healing abutment, whereas a partial
15.1 Two vertical incisions are made on each side of the implant, beyond the muco gingival line.
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thickness flap is raised in the apical part. The osseous surface will be covered by a newly formed gingival tissue after directed healing. In practice, we tend to prefer another technique, as described by Vence.11 It causes less pain and uses a dissection outlining the keratinized site with partialthickness horizontal and vertical incisions. A split thickness flap is elevated and buccally repositioned (Fig. 15.2). The flap is positioned beyond the muco gingival line and sutured to the periosteum in an apical position (Fig. 15.3). An attached non mobile tissue with intimate adaptation provides the implant’s structure emergence (Fig. 15.4). It is recommended that this flap is created during the second phase of the surgery, when the healing screws are being put into position, as this provides greater access to the alveolar bone as well as to the implant, and facilitates the deepening of the vestibule. However, this method may sometimes create unaesthetic gingival hyperplasia around the implant, which can be improved by gingivoplasty.
15.2 A split thickness flap is elevated.
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15.3 The flap is positioned beyond the gingival line and secured to the periosteum in an apical position.
15.4 An attached non mobile tissue with intimate adaptation to emerging implant structures has been provided.
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There is no attached gingiva remaining at the recipient site In these cases it may be necessary to use the pedicled lateral sliding flap described by Gruppe and Warren.12 This procedure uses the gingiva adjacent to the implant, and the split-thickness flap is secured laterally on the receptor site with sutures (Fig. 15.5 and 15.6). Generally speaking pedicled flaps offer several advantages: • The pedicled flaps are aesthetic, the colour of the soft peri-implant tissues is equivalent to that of the donor site.
15.5 The split-thickness flap is secured laterally.
15.6 Peri-implant soft tissue health and stability are excellent.
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• There is only a single operating site required because of its proximity of the donor site. • The pedicle improves the vascularization of the tissues. However some disadvantages must also be mentioned: • The donor site has to have a substantial quantity of keratinized gingival tissue for the procedure to work. • The presence of some anatomical obstacles, such as the mental nerve, could contraindicate this kind of flap in particular areas.
15.4.3 The attached gingiva is missing around the implants and no donor area is available near to the recipient site Where the attached gingiva is missing around the implants the only solution is to perform an epithelio-connective graft. The epithelio-connective graft (ECG): free soft tissue graft The ECG was first described by Bjorn in 1963.13 Aside from cases where the gingival is missing, this approach is also recommended when the vestibule is not deep enough.10 The graft of keratinized tissue is used to replace the alveolar mucous membrane and is sutured to the periosteum. An appropriate vestibular depth and a band of attached tissue can then be restored. Case report 2 • • • • •
A 29 year-old man lost tooth 21 (incisor) a long time ago. A severe osseous resorption was observed. A chin bone graft has been performed at the site of tooth 21. The option of a partially submerged implant was retained. The margin of the temporary restoration overlapped with the alveolar mucosa (Fig. 15.7).
15.5 Surgical technique 15.5.1 Preparation of the recipient site The epithelium is reduced through a dissection in partial thickness, while a horizontal incision above the muco gingival line and two vertical deep incisions are made in the vestibule. A very high horizontal incision joins the two vertical incisions, and the mucosal part is removed. Residual elastic and muscular tissues are excised to create a uniform periosteal site (Fig. 15.8).
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15.7 Preoperative view: the margin temporary restoration overlaps the alveolar mucosa.
15.8 A rigid periosteal recipient bed is created.
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15.5.2 Preparation of the donor site The palate is the most common donor site. The graft is harvested distally from the first molar, away from the teeth collar; two parallel incisions perpendicular to the first ones and reaching the bone delimit a keratinized tissue rectangle, its area being similar to the receiving site. The graft is taken in split thickness and the donor site is dressed with a vegetal absorbable haemostatic dressing. A protective palatal stent is provided in order to protect the donor site.
15.5.3 Apply and immobilize the graft on the recipient site The connective tissue is removed (Fig. 15.9) and the graft is thinned out to an optimal thickness of 1.5 mm and placed on the recipient site. The gingival graft has been adapted around the implant abutment. The next step consists of suturing the graft into the periosteum, using mattress sutures (Vicryl 5/0) in order to immobilize the graft (Fig. 15.10). A nice band of keratinized gingival tissue has been successfully reconstructed (Fig. 15.11). This technique offers the following advantages. The Epithelial Connective Tissue Graft generates a healthy keratinized gingiva within the peri-implant environment. It is fixed to the bone and has a low risk of inflammation. The ECG also provides a deeper vestibule and thus provides better access for brushing teeth. However there are some disadvantages which cannot be ignored. The aesthetic result is worse than the result provided by pedicled flaps: over time, a white
15.9 The epithelialized palatal graft.
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15.10 Immobilization of the graft with mattress sutures.
15.11 Three months later. A new temporary restoration has been delivered and an adequate band of attached tissue has been reconstructed.
opaline aspect appears (Fig. 15.12). Also, the ECG procedure requires a second surgical site: it is an additional constraint for the patient and there is some pain to be expected during the healing process. It is important to avoid making a graft that is too small or too thin. Indeed, the soft tissue augmentation on the implant site could fail when reduced grafts are performed, due to the frequent secondary graft retraction.
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15.12 Opaline white unaesthetic aspect.
The sub-epithelio connective tissue graft A thin and poor keratinized tissue is often the source of recessions, leading to a poor aesthetic result with titanium visible at the mucosal margin. When a sub-epithelium connective tissue graft is performed using a tissue poor in keratin, it will result in a thickening of the receptor tissue. In this way, a given level of stability of the marginal gingiva around the implant will be secured. The sub-epithelial connective tissue graft offers the following advantages: • The palatal gingiva presents a large quantity of connective tissue. • It is a one step surgery. • There is a double blood supply for the graft, from the periostium as well as from the internal side of the flap. • The colour of the peri-implant tissues remain the same. • The likely requirement of a post-surgical reattempt is limited. There are many surgical techniques available and we are now going to describe the technique proposed by Raetzke, and then the one by Langer–Langer, known as the ‘closed flap’ and the ‘open flap’, respectively.14,15 In the Raetzke technique (1985) (the pouch or envelope technique) the recipient site is closed.11 This is a blind technique, and therefore is more difficult. Case study: the Raetzke technique An ECG had been successfully reconstructed in order to obtain an adequate band of attached tissue (Case report 1 describes the ECG), but there was a small metal
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margin of the prosthesis still visible. The patient asked us to improve the aesthetic appearance of the implant, and we decided to use the Raetzke technique. Preparing the recipient site • The secular epithelium is removed. • A split-thickness dissection is performed on the mesial, distal and apical sides of the recession around the implant body. • The partial thickness flap is raised. Preparing the donor site A palatal sub-periosteal dissection is performed and the connective tissue is harvested and positioned passively under the dissection of the recipient site, rather like a letter in an envelope, and immobilized (Fig. 15.13). The suturing of the graft begins mesially or distally, first by introducing the needle in the buccal mucosa, at the bottom of the envelope, then going through the graft and coming out on the buccal side a few millimetres away from the original entry point of the needle. This is achieved by bringing the graft gently into the envelope, then positioning and adapting it perfectly onto the periostium by tightening the suture threads with two O type knots (Fig. 15.14). The sutures are removed ten days later. The six-month post operative appearance demonstrates an excellent periimplant soft tissue and the correction of the aesthetic failure (Fig. 15.15).
15.13 Passive adaptation of the connective tissue graft within the pouch.
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15.14 Two sutures are secured to prevent coronal displacement of the graft.
15.15 Six-month post operative view. Soft tissue at grafted area is healthy and stable.
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Advantages The advantage of this procedure is good vascularization, which leads to a better aesthetical result. Disadvantages Closed access makes the procedure more difficult because the envelope flap must not be perforated during the dissection, while the stabilization of the connective tissue is quite delicate. The technique is not recommended in cases where the vestibule is not deep enough. The sub-epithelial connective tissue graft with an open recipient site was described by Langer and Langer 1985.15 This technique, which uses releasing incisions on the recipient site, is easier to perform, gives direct visual access to the dissection, and makes for the easier positioning of coronal flap. However, the use of vertical incisions can reduce the blood supply to both the flap and the graft. Case report: the Langer–Langer technique A 30 year-old female patient presented with a class II malocclusion and tooth 12 agenesia. Three phases of treatment were planned: 1. A sagittal osteotomy is performed. 2. An implant is positioned at the site of the missing tooth. 3. A genioplasty is performed. Six months after delivering the final restoration, a recession defect appears, showing the metal margin of the implant crown (Fig. 15.16) and the patient’s high lip line exposed the aesthetic failure when she smiled. The Langer–Langer technique was used to improve the aesthetical result. Preparing the recipient site A horizontal intra sulcular incision is performed first in the mesial part, and then in the distal part, of the defective tissue. For a coronal flap repositioning, the epithelium of the narrowing papillas is removed. Next, two vertical releasing incisions are extended beyond the muco gingival line. A partial split-thickness buccal flap is elevated, and a uniform periosteal receipt site is created (Fig. 15.17).
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15.16 The metal margin of the implant crown is visible.
15.17 A uniform periosteal recipient site has been prepared.
Donor site The necessary connective tissue is harvested from the palate and the donor site is dressed with a vegetable absorbable dressing, which serves to close the donor site, to protect the site and improve patient comfort in the early post-operative period (Fig. 15.18).
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15.18 Closure of the donor site wound.
Stabilization of the graft The epithelium is removed from the graft, adjusted and stabilized coronally with sutures through the papillas at the site where it has been removed. Then the connective tissue graft is sutured laterally and apically to the periostium. The cooptation of the passing flap is verified, before recovering the graft and releasing incisions are performed (Fig. 15.19). Some analgesic medications, as well as mouthwash, are prescribed and the sutures are removed ten days later.
15.19 The cover flap is secured coronally and laterally.
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15.20 Six months post-operative view demonstrates complete metal margin coverage. Peri-implant health is excellent.
Six months later we had achieved an excellent peri-implant soft tissue aesthetic and healthy result (Fig. 15.20).
15.6 Conclusions It is important always to remember that aesthetic failure is very difficult to correct. Unaesthetic complications can only be resolved by mucogingival surgery (Fig. 15.21). A rigorous prosthetic pre-implant analysis and careful planning help to avoid these complications. The success of the implant therapeutics depends, as
15.21 Important aesthetic problem. The removal of the implant was the only solution to eliminate the aesthetic failure.
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in periodontology, on rigorous control of the bacterial plaque associated with an optimized environment of the soft tissues, in order to prevent the formation mucositis and peri-implantis.
15.7 References 1 James R (1973) Periodontal considerations in implant dentistry. J Prosthet Dent 30(2): 202–9. 2 Wennstrom J, Lindhe J (1983) Role of attached gingiva for maintenance of periodontal health. Healing following excisional and grafting procedures in dogs. J Clin Periodontol 10(2): 206–21. 3 Maynard JG, Wilson RD (1979) Physiologic dimensions of the periodontium significant to the restorative dentistry. J Periodontol 50: 170–74. 4 Mongeot M (1989) Biological criteria for osseointegration. J Parodontol 8(1): 97–104. 5 Ericsson I, Persson LG, Berglund T, Lindhe J (1995) Different types of inflammatory reactions in peri implant soft tissues. J Clin Periodontol 22(3): 255–61. 6 Wennstrom Jl, Bengasi F, Leklhom U (1994) The influence of the masticory mucosa on the peri-implant tissue condition. Clin Oral Implants Res 5(1): 1–8. 7 Warrer K, Buser D, Lang NP, Karring T (1995) Plaque-induced peri-implantis in the presence or absence of keratinized mucosa. An experimental study in monkeys. Clin Oral Implant Res 6(3): 131–8. 8 Ouhayoun JP (1991) Gingival grafts and implant surgery. J Parodontol 10(2): 191–5. 9 Schroeder A, Van der Zypen E, Stich H, Sutter F (1981) The reactions of bone, connective tissue, and epithelium to endosteal implants with titanium-sprayed surfaces. J Maxillofac Surg 9(1): 15–25. 10 Nabers SCL (1954) Repositioning the attached gingival. J Periodontol 25: 38. 11 Vence MG (1990) Vestibular transposed palated flap (VTPF) in implantology. Clin Odontol 11(5): 321–6. 12 Grupe J, Warren R (1956) Repair of gingival defects by a sliding flap operation. J Periodontol 27: 92–101. 13 Bjorn H (1963) Free transplantation of gingiva propria. Swen Tondlak Tidskr 22: 684. 14 Raetzke PB (1985) Covering localized areas of root exposure employing the ‘envelope’ technique. J Periodontol 56(7): 397–402. 15 Langer B, Langer L (1985) Subepithelial connective tissue graft technique for root coverage. J Periodontol 56(12): 715–20.
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15.1 Introduction Considering the impact of the periodontal environment within the field of implantology, Robert James argued in 1973 that the same surgery that was used to improve the environment and vitality of a natural tooth, would also be similarly beneficial in the case of a dental implant.1 Therefore, his opinion was that both the quality and the quantity of tissues surrounding the implants were of major importance for successful implant treatment. Nevertheless, at that time, the main objective of implantologists was to obtain the osseointegration of dental implants. Nowadays, the aesthetical aspect of such treatment has become just as essential as the purely medical objectives. In this chapter, we are going to describe the optimal environment that should be present or created around an implant to optimize its durability.
15.2 Muco gingival environment around natural teeth In a healthy situation, we would expect to find a muco gingival environment around the natural teeth. It may be argued that when a rigorous control of plaque is performed, a band of keratinized gingival around the tooth does not affect the periodontal health.2 However, the presence of an aesthetical and sub-gingival prosthesis leads to an increase in dental plaque. Therefore, in such a case, some keratinized gingiva is required.3 In the event that we discover a frenum, which tends to open the sulcus and thereby allow for the development of a bacterial environment, the frenum needs to be removed and a band of attached gingiva needs to be created. 284 © Woodhead Publishing Limited, 2011
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15.3 Role of the keratinized gingiva around the implants It is necessary to distinguish between the soft tissues surrounding the implants and the periodontium. ‘Gingiva’ is the term that we use for the tissues surrounding natural teeth. However, we use the term ‘Mucosa’ to describe the tissues surrounding implants. The peri-implant mucosa is a scar tissue, fibrous, poor in cells and less vascularized than the periodontium. Compared to the periodontium, the soft tissue surrounding the implants does not show any cement, desmodontium, dentoperiostial or dento-gingival fibres. Among the specialists, some controversial approaches have been developed and some studies take the view that the attached gingiva is not an essential element in the implant protocol. Scandinavian teams do not consider the quality of the tissue surrounding the implant.4 Provided that a good oral hygiene is maintained, the absence of attached gingiva around the implant does not significantly impact upon the reliability of the peri-implant biologic seal.5,6 According to Buser, a non mobile band of tissue is essential to secure the integrity of the biological seal.7 Ouhayoun considers a large keratinized gingival band around the implants to be more favourable. In his view, this provides adequate foundations to resist mechanical influence, and also contributes to better gingival hygiene.8 A peri-implant mucosa is more likely to be affected by a mechanical injury than the gingiva, inducing a greater amount of inflammation. If there is an infragingival implant prosthesis, or if implants are close to a zone of muscular tension, management of the tissue attached around the implant restorations seems necessary. To summarize, most clinicians agree that an adequate zone of attached soft tissue, which has been intimately adapted to the emergence of the implant abutment, is necessary to ensure the long term success of the implant rehabilitation.9 Therefore, we will now describe our various management techniques, which have been adapted according to the amount of soft tissues present.
15.4 Developing a favourable environment around the implants When aiming to develop a favourable environment around the implants, there are a number of different situations that may present themselves, as follows.
15.4.1 The amount of keratinized gingiva is normal Where the amount of keratinized gingiva is normal, the soft tissues should be protected and handled with care over the course of the different steps of the treatment.
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15.4.2 The quantity of attached and keratinized gingiva is reduced There is some attached gingiva remaining at the recipient site In these cases a pedicled flap can be raised and fixed apically or laterally to the implant site.10 Case report 1 In the following case report, we can observe a view which demonstrates the high muscle attachment. A horizontal incision is made lingually or palatally in the keratinized tissue. Then two vertical incisions are made on each side of the implant, beyond the muco gingival line (Fig. 15.1). A muco periostal flap is raised in the coronal part of the implant, creating easier access to the healing abutment, whereas a partial
15.1 Two vertical incisions are made on each side of the implant, beyond the muco gingival line.
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thickness flap is raised in the apical part. The osseous surface will be covered by a newly formed gingival tissue after directed healing. In practice, we tend to prefer another technique, as described by Vence.11 It causes less pain and uses a dissection outlining the keratinized site with partialthickness horizontal and vertical incisions. A split thickness flap is elevated and buccally repositioned (Fig. 15.2). The flap is positioned beyond the muco gingival line and sutured to the periosteum in an apical position (Fig. 15.3). An attached non mobile tissue with intimate adaptation provides the implant’s structure emergence (Fig. 15.4). It is recommended that this flap is created during the second phase of the surgery, when the healing screws are being put into position, as this provides greater access to the alveolar bone as well as to the implant, and facilitates the deepening of the vestibule. However, this method may sometimes create unaesthetic gingival hyperplasia around the implant, which can be improved by gingivoplasty.
15.2 A split thickness flap is elevated.
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15.3 The flap is positioned beyond the gingival line and secured to the periosteum in an apical position.
15.4 An attached non mobile tissue with intimate adaptation to emerging implant structures has been provided.
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There is no attached gingiva remaining at the recipient site In these cases it may be necessary to use the pedicled lateral sliding flap described by Gruppe and Warren.12 This procedure uses the gingiva adjacent to the implant, and the split-thickness flap is secured laterally on the receptor site with sutures (Fig. 15.5 and 15.6). Generally speaking pedicled flaps offer several advantages: • The pedicled flaps are aesthetic, the colour of the soft peri-implant tissues is equivalent to that of the donor site.
15.5 The split-thickness flap is secured laterally.
15.6 Peri-implant soft tissue health and stability are excellent.
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• There is only a single operating site required because of its proximity of the donor site. • The pedicle improves the vascularization of the tissues. However some disadvantages must also be mentioned: • The donor site has to have a substantial quantity of keratinized gingival tissue for the procedure to work. • The presence of some anatomical obstacles, such as the mental nerve, could contraindicate this kind of flap in particular areas.
15.4.3 The attached gingiva is missing around the implants and no donor area is available near to the recipient site Where the attached gingiva is missing around the implants the only solution is to perform an epithelio-connective graft. The epithelio-connective graft (ECG): free soft tissue graft The ECG was first described by Bjorn in 1963.13 Aside from cases where the gingival is missing, this approach is also recommended when the vestibule is not deep enough.10 The graft of keratinized tissue is used to replace the alveolar mucous membrane and is sutured to the periosteum. An appropriate vestibular depth and a band of attached tissue can then be restored. Case report 2 • • • • •
A 29 year-old man lost tooth 21 (incisor) a long time ago. A severe osseous resorption was observed. A chin bone graft has been performed at the site of tooth 21. The option of a partially submerged implant was retained. The margin of the temporary restoration overlapped with the alveolar mucosa (Fig. 15.7).
15.5 Surgical technique 15.5.1 Preparation of the recipient site The epithelium is reduced through a dissection in partial thickness, while a horizontal incision above the muco gingival line and two vertical deep incisions are made in the vestibule. A very high horizontal incision joins the two vertical incisions, and the mucosal part is removed. Residual elastic and muscular tissues are excised to create a uniform periosteal site (Fig. 15.8).
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15.7 Preoperative view: the margin temporary restoration overlaps the alveolar mucosa.
15.8 A rigid periosteal recipient bed is created.
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15.5.2 Preparation of the donor site The palate is the most common donor site. The graft is harvested distally from the first molar, away from the teeth collar; two parallel incisions perpendicular to the first ones and reaching the bone delimit a keratinized tissue rectangle, its area being similar to the receiving site. The graft is taken in split thickness and the donor site is dressed with a vegetal absorbable haemostatic dressing. A protective palatal stent is provided in order to protect the donor site.
15.5.3 Apply and immobilize the graft on the recipient site The connective tissue is removed (Fig. 15.9) and the graft is thinned out to an optimal thickness of 1.5 mm and placed on the recipient site. The gingival graft has been adapted around the implant abutment. The next step consists of suturing the graft into the periosteum, using mattress sutures (Vicryl 5/0) in order to immobilize the graft (Fig. 15.10). A nice band of keratinized gingival tissue has been successfully reconstructed (Fig. 15.11). This technique offers the following advantages. The Epithelial Connective Tissue Graft generates a healthy keratinized gingiva within the peri-implant environment. It is fixed to the bone and has a low risk of inflammation. The ECG also provides a deeper vestibule and thus provides better access for brushing teeth. However there are some disadvantages which cannot be ignored. The aesthetic result is worse than the result provided by pedicled flaps: over time, a white
15.9 The epithelialized palatal graft.
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15.10 Immobilization of the graft with mattress sutures.
15.11 Three months later. A new temporary restoration has been delivered and an adequate band of attached tissue has been reconstructed.
opaline aspect appears (Fig. 15.12). Also, the ECG procedure requires a second surgical site: it is an additional constraint for the patient and there is some pain to be expected during the healing process. It is important to avoid making a graft that is too small or too thin. Indeed, the soft tissue augmentation on the implant site could fail when reduced grafts are performed, due to the frequent secondary graft retraction.
© Woodhead Publishing Limited, 2011
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15.12 Opaline white unaesthetic aspect.
The sub-epithelio connective tissue graft A thin and poor keratinized tissue is often the source of recessions, leading to a poor aesthetic result with titanium visible at the mucosal margin. When a sub-epithelium connective tissue graft is performed using a tissue poor in keratin, it will result in a thickening of the receptor tissue. In this way, a given level of stability of the marginal gingiva around the implant will be secured. The sub-epithelial connective tissue graft offers the following advantages: • The palatal gingiva presents a large quantity of connective tissue. • It is a one step surgery. • There is a double blood supply for the graft, from the periostium as well as from the internal side of the flap. • The colour of the peri-implant tissues remain the same. • The likely requirement of a post-surgical reattempt is limited. There are many surgical techniques available and we are now going to describe the technique proposed by Raetzke, and then the one by Langer–Langer, known as the ‘closed flap’ and the ‘open flap’, respectively.14,15 In the Raetzke technique (1985) (the pouch or envelope technique) the recipient site is closed.11 This is a blind technique, and therefore is more difficult. Case study: the Raetzke technique An ECG had been successfully reconstructed in order to obtain an adequate band of attached tissue (Case report 1 describes the ECG), but there was a small metal
© Woodhead Publishing Limited, 2011
Periodontal surgery related to alveolar bone reconstruction
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margin of the prosthesis still visible. The patient asked us to improve the aesthetic appearance of the implant, and we decided to use the Raetzke technique. Preparing the recipient site • The secular epithelium is removed. • A split-thickness dissection is performed on the mesial, distal and apical sides of the recession around the implant body. • The partial thickness flap is raised. Preparing the donor site A palatal sub-periosteal dissection is performed and the connective tissue is harvested and positioned passively under the dissection of the recipient site, rather like a letter in an envelope, and immobilized (Fig. 15.13). The suturing of the graft begins mesially or distally, first by introducing the needle in the buccal mucosa, at the bottom of the envelope, then going through the graft and coming out on the buccal side a few millimetres away from the original entry point of the needle. This is achieved by bringing the graft gently into the envelope, then positioning and adapting it perfectly onto the periostium by tightening the suture threads with two O type knots (Fig. 15.14). The sutures are removed ten days later. The six-month post operative appearance demonstrates an excellent periimplant soft tissue and the correction of the aesthetic failure (Fig. 15.15).
15.13 Passive adaptation of the connective tissue graft within the pouch.
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15.14 Two sutures are secured to prevent coronal displacement of the graft.
15.15 Six-month post operative view. Soft tissue at grafted area is healthy and stable.
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Advantages The advantage of this procedure is good vascularization, which leads to a better aesthetical result. Disadvantages Closed access makes the procedure more difficult because the envelope flap must not be perforated during the dissection, while the stabilization of the connective tissue is quite delicate. The technique is not recommended in cases where the vestibule is not deep enough. The sub-epithelial connective tissue graft with an open recipient site was described by Langer and Langer 1985.15 This technique, which uses releasing incisions on the recipient site, is easier to perform, gives direct visual access to the dissection, and makes for the easier positioning of coronal flap. However, the use of vertical incisions can reduce the blood supply to both the flap and the graft. Case report: the Langer–Langer technique A 30 year-old female patient presented with a class II malocclusion and tooth 12 agenesia. Three phases of treatment were planned: 1. A sagittal osteotomy is performed. 2. An implant is positioned at the site of the missing tooth. 3. A genioplasty is performed. Six months after delivering the final restoration, a recession defect appears, showing the metal margin of the implant crown (Fig. 15.16) and the patient’s high lip line exposed the aesthetic failure when she smiled. The Langer–Langer technique was used to improve the aesthetical result. Preparing the recipient site A horizontal intra sulcular incision is performed first in the mesial part, and then in the distal part, of the defective tissue. For a coronal flap repositioning, the epithelium of the narrowing papillas is removed. Next, two vertical releasing incisions are extended beyond the muco gingival line. A partial split-thickness buccal flap is elevated, and a uniform periosteal receipt site is created (Fig. 15.17).
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15.16 The metal margin of the implant crown is visible.
15.17 A uniform periosteal recipient site has been prepared.
Donor site The necessary connective tissue is harvested from the palate and the donor site is dressed with a vegetable absorbable dressing, which serves to close the donor site, to protect the site and improve patient comfort in the early post-operative period (Fig. 15.18).
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15.18 Closure of the donor site wound.
Stabilization of the graft The epithelium is removed from the graft, adjusted and stabilized coronally with sutures through the papillas at the site where it has been removed. Then the connective tissue graft is sutured laterally and apically to the periostium. The cooptation of the passing flap is verified, before recovering the graft and releasing incisions are performed (Fig. 15.19). Some analgesic medications, as well as mouthwash, are prescribed and the sutures are removed ten days later.
15.19 The cover flap is secured coronally and laterally.
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15.20 Six months post-operative view demonstrates complete metal margin coverage. Peri-implant health is excellent.
Six months later we had achieved an excellent peri-implant soft tissue aesthetic and healthy result (Fig. 15.20).
15.6 Conclusions It is important always to remember that aesthetic failure is very difficult to correct. Unaesthetic complications can only be resolved by mucogingival surgery (Fig. 15.21). A rigorous prosthetic pre-implant analysis and careful planning help to avoid these complications. The success of the implant therapeutics depends, as
15.21 Important aesthetic problem. The removal of the implant was the only solution to eliminate the aesthetic failure.
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in periodontology, on rigorous control of the bacterial plaque associated with an optimized environment of the soft tissues, in order to prevent the formation mucositis and peri-implantis.
15.7 References 1 James R (1973) Periodontal considerations in implant dentistry. J Prosthet Dent 30(2): 202–9. 2 Wennstrom J, Lindhe J (1983) Role of attached gingiva for maintenance of periodontal health. Healing following excisional and grafting procedures in dogs. J Clin Periodontol 10(2): 206–21. 3 Maynard JG, Wilson RD (1979) Physiologic dimensions of the periodontium significant to the restorative dentistry. J Periodontol 50: 170–74. 4 Mongeot M (1989) Biological criteria for osseointegration. J Parodontol 8(1): 97–104. 5 Ericsson I, Persson LG, Berglund T, Lindhe J (1995) Different types of inflammatory reactions in peri implant soft tissues. J Clin Periodontol 22(3): 255–61. 6 Wennstrom Jl, Bengasi F, Leklhom U (1994) The influence of the masticory mucosa on the peri-implant tissue condition. Clin Oral Implants Res 5(1): 1–8. 7 Warrer K, Buser D, Lang NP, Karring T (1995) Plaque-induced peri-implantis in the presence or absence of keratinized mucosa. An experimental study in monkeys. Clin Oral Implant Res 6(3): 131–8. 8 Ouhayoun JP (1991) Gingival grafts and implant surgery. J Parodontol 10(2): 191–5. 9 Schroeder A, Van der Zypen E, Stich H, Sutter F (1981) The reactions of bone, connective tissue, and epithelium to endosteal implants with titanium-sprayed surfaces. J Maxillofac Surg 9(1): 15–25. 10 Nabers SCL (1954) Repositioning the attached gingival. J Periodontol 25: 38. 11 Vence MG (1990) Vestibular transposed palated flap (VTPF) in implantology. Clin Odontol 11(5): 321–6. 12 Grupe J, Warren R (1956) Repair of gingival defects by a sliding flap operation. J Periodontol 27: 92–101. 13 Bjorn H (1963) Free transplantation of gingiva propria. Swen Tondlak Tidskr 22: 684. 14 Raetzke PB (1985) Covering localized areas of root exposure employing the ‘envelope’ technique. J Periodontol 56(7): 397–402. 15 Langer B, Langer L (1985) Subepithelial connective tissue graft technique for root coverage. J Periodontol 56(12): 715–20.
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