Gingival Attachment Loss: Evaluation and Surgical Options Daniel J. Melker, DDS Attached connective tissue (a.k.a. attached tissue) in the simplest terms is the body s only barrier between the underlying bone and bacteria. It forms a mechanical obstruction to forces that would strip away less resilient tissue. A compromised barrier will result in continued bony destruction in the area of recession. A lack of attached tissue may lead to bacteria and calculus accumulation that in rare instances can result in an abscess. There are two very distinct differences between attached tissue and mucosa. First, attached tissue is an avascular tissue with a dense fibrous meshwork. Second, attached tissue can prevent bacterial infiltration as well as provide protection of the underlying structures because of its resiliency. On the other hand, mucosa is highly vascular and provides little resistance to the abuse of improper tooth brushing. Figures 1 and 2 demonstrate what attached tissue is and how it is measured. Recession can occur through a variety of mechanisms resulting in functional and esthetic problems. It is important to recognize that tissue that is challenged by a partial denture clasp or retraction cord has an increased chance for developing recession. Recession after final impression or crown insertion can be problematic for the practitioner and the patient. fig. 1 fig. 2 Continued on page 60 58
Continued from page 58 How much attached keratinized tissue is enough? In gingival health, 1-2 mm of attached keratinized tissue is adequate 1. The following circumstances are good indications for a soft tissue graft: 1. Areas with minimal to no attached tissue especially in the presence of poor plaque control or frenal pull (Figs. 3 and 4). 2. Areas that are an esthetic concern to the patient. 3. Areas of progressive recession. Gingival recession should be noted at the initial exam and followed over time. Some of these areas may stay stable, but any that advance should be considered for grafting. An area that is allowed to progress may be harder to treat than one that is addressed promptly. 4. Young patients with early signs of recession should be monitored vigilantly because they are more likely to progress, due to the relative number of years they will use their teeth. Conversely, an elderly patient with early recession can be maintained provided they have adequate attached tissue. Sometimes serious recession is overlooked due to a focus on pocket depth alone. For example, if a patient has a buccal probing of six millimeters, there is a deep periodontal concern. However, if a patient has 3 mm of recession and a 3 mm sulcular probing, this is often dismissed as a normal probing. In fact, the second patient has the equivalent of a 6 mm probing and there is a need for periodontal treatment. The most predictable areas for complete root coverage are Miller Class I or II defects (see Miller Classification System Chart for description). 2 Current soft tissue grafting techniques are divided into two categories: free gingival graft and connective tissue graft. The Free Gingival Graft Sullivan and Atkins were two pioneers of the free gingival graft 3. Free gingival grafts are very predictable in gaining attached, keratinized tissue, and can provide root coverage, particularly in the lower anterior. However, there is donor site morbidity due to the presence of secondary intention healing, which often results in an unaesthetic patch of gingival tissue. Root coverage is less predictable over large areas and was originally not thought to be possible. Dr. Atkins once explained the occasional root coverage achieved through grafting as, fortuitous vascular link- up. Figure 5 represents an example of a free gingival graft that successfully reestablished root coverage. The Subepithelial Connective Tissue Graft The connective tissue graft has several surgical variations for the recipient site: coronal advancement, tunnel technique or a pedicle flap. The only additional surface keratinazation that occurs will happen over exposed donor tissue 4. The donor connective tissue can be harvested a variety of ways, and they are described in more detail in the International Journal of Periodontics and Restorative Dentistry 5. Generally speaking, the donor site will have minimal post op discomfort, and primary closure is possible in some patients. Figure 6 is a typical example of one week healing of a connective tissue graft donor site with primary closure. The connective tissue graft has become a reliable tool in the periodontal armamentarium, and offers some advantages over the free gingival graft. The connective tissue graft offers the possibility for more predictable root coverage because it gets a blood supply Miller classification system Class I: Marginal recession coronal to the mucogingival junction with no periodontal loss in the interdental areas Class II: Similar to class I but the defect extends beyond the mucogingival junction Class III: Recession either to or beyond the mucogingival junction with some soft tissue or bone loss interdentally Class IV: Similar to class III except the interdental soft tissue or bone loss is severe *Tooth position also factors in to whether a root can be covered. fig. 3 fig. 4 fig. 5 fig. 6 Continued on page 62 60
Continued from page 60 from the outer flap and lateral blood supply from the adjacent tissue. The root surface of the grafted site does not provide any blood supply. Additionally, post-operative discomfort is minimal compared to a free gingival graft (Figures 7-11). Acellular Dermal Matrix Graft The acellular dermal matrix graft (AlloDerm) can be a substitute for donor connective tissue. It is recommended for use as a replacement for donor connective tissue, but it is not to be used as a substitute material for a free gingival graft. It is not appropriate for all cases. In contrast to using the patient s connective tissue, AlloDerm must be completely covered by an overlying flap or tissue, and it will not result in an increase in keratinized tissue 6. It is generally considered more technique-sensitive than the use of donor tissue from the patient. From a practical standpoint, if the tissue in the area of the recession is thin such that the markings of a periodontal probe can be read through it, the use of this material is relatively contraindicated. In this situation it is likely to slough through the tissue and fail. In addition, this material may not fair well as host connective tissue long-term if covering only one tooth 7. However, if the tissue is thick and more than three teeth need to be covered, it is a viable and patient-friendly alternative to connective tissue from the patient s palate. General surgical considerations for success In general, there are several things that should be done to help ensure predictable root coverage whether it be a free gingival graft, connective tissue graft, or graft with acellular dermal matrix. The following are a few things to ensure predictable root coverage: Root preparation is critical. Prominent roots should be reduced and moved inward, most surgeons use a bur to do so. Sensitivity should not be a long-term concern especially if the area is a Miller class I or II defect. In addition, by changing the prominence of the root, a Miller class III defect can convert into a I or II that can be covered by a graft. Most surgeons do some type of root conditioning with citric acid, tetracycline, phosphoric acid or EDTA. Relieving a frenal pull and a tension free closure is critical, particularly if AlloDerm is used. Continued on page 64 Relieving a frenal pull and a tension free closure is critical, particularly if AlloDerm is used. fig. 7 fig. 8 fig. 9 fig. 10 fig. 11 62
Continued from page 62 A graft will not adhere to restorative materials. Geristore is a material mentioned as one a graft may adhere to, but there is only limited evidence to support that 6. Connective tissue grafts are an alternative to class V restorations. (Figures 12-14) Restorative connection Looking at basic readily visible biologic factors such as tooth position, the amount and thickness of naturally occurring attached keratinized tissue, and frenal pull are things that should be given primary consideration (Fig. 15-16). Attached tissue plays an important role in resisting iatrogenic forces. When placing a subgingival restoration or packing cord, thin areas of attached tissue or areas with no true attachment can be prone to recession 9. Keeping that in mind, there are some biologic factors to consider for successful long-term restoration: There should be attached tissue present with dense connective tissue to serve as a barrier for traumatic procedures that occur during restoration such as preparing the restorative margin, impression taking, and cementation. Thin tissue should be corrected prior to restoration. Existing recession with unattached connective tissue must be treated to prevent further breakdown. The trauma that occurs during restoration will accelerate the recession. Even something as benign as taking an impression can elicit additional recession and periodontal compromise in the absence of attached tissue. The tissue is not always as it seems. For example, when aggressive scaling and curettage is performed prior to restorative treatment the attachment seems to improve with the removal of inflammation. In spite of this improved gingival health the new attachment is more likely to be a long junctional epithelial close adaptation. Dense connective tissue is far different than junctional epithelium. When the subsequent impression is taken into junctional epithelium, the tenuous attachment will break away. Many times this recession is discovered months after the restorative procedures. Therefore, it is critical to have dense connective tissue as opposed to a junctional epithelium tenuous attachment. A firm probing of potential restorative sites 3-4 weeks post periodontal therapy will easily break down a false attachment of junctional epithelium, and provide the dentist with an early warning that future recession is very likely. Addressing this issue prior to final restoration will avoid costly and frustrating remakes in many cases. In the esthetic zone in particular, this is a concern. If recession is seen after restorative work, a close examination of the original amount of attached tissue may reveal the underlying cause. Thin tissue or areas that had very little attached tissue should be considered as the most likely cause of the post-restorative recession. Occlusion is another consideration that is frequently been mentioned as a cause of recession, but has been a difficult risk factor to pin down in the literature. Summary Root coverage procedures can be predictable, esthetic and rewarding if properly diagnosed and treated. There are criteria that can determine whether root coverage is achievable preoperatively. The advent of the connective tissue graft has made soft tissue grafting considerably more acceptable to patients in terms of post-operative discomfort. When restoring teeth, attached connective tissue serves to protect the underlying periodontal structures from trauma caused during margin preparation, impression taking and cementation procedures. Esthetic compromise as well as loss of periodontal support can result if an inadequate amount of attached tissue is present. The author would like to acknowledge Ralph Wilson, DDS, for providing the photographs and text assistance with this article. Continued on page 66 fig. 12 fig. 13 fig. 14 fig. 15 fig. 16 64
Continued from page 64 References: 1. Lang NP, Loe H. The relationship between the width of keratinized gingiva and gingival health. J Periodontol 1972;43:623-627 2. Miller PD Jr. A classification of marginal tissue recession. Int J Periodontics Restorative Dent 1985;5(2):8-13 3. Sullivan HC, Atkins JH. Free autogenous gingival grafts: I. Principles of successful grafting. Periodontics 1968;6:121-129. 4. Cordioli G et al. Comparison of two techniques of subepithelial connective tissue graft in the treatment of gingival recessions. J Periodontol 2001;72:1470-1476. 5. Chiun-Lin L, Weisgold AS. Connective tissue graft:a classification for incision design from the palatal site and clinical case reports. Int J Periodontics Restorative Dent 2002;22:373-379. 6. Tal H et al. Root coverage of advanced gingival recession: a comparative study between acellular dermal matrix allograft and subepithelial connective tissue grafts. J Periodontol 2002;73:1405-1411. 7. Harris RJ. A short-term and long-term comparison of root coverage with an acellular dermal matrix graft and subepithelial graft. J Periodontol 2004;75:734-743. 8. Dragoo MR. Resin-ionomer and glass-ionomer cements: Part II, human clinical and histological wound healing responses in specific periodontal lesions. Int J Periodontics Restorative Dent. 1997 Feb;17:75-87. 9. Maynard JG Jr, Wilson RD. Physiologic dimensions of the periodontium significant to the restorative dentist. J Periodontol 1979;50:170-174 Daniel J. Melker, DDS has been in the private practice of periodontics for the past 29 years in Clearwater, Florida. He currently lectures to the University of Florida Periodontic and Prosthodontic graduate programs on the Periodontic Restorative relationship and has also lectured at Baylor University as well as several dental associations and study clubs across the United States. To contact Dr. Melker please see him on the www..com message boards in the Periodontics section or email him at djmelker@yahoo.com. 66