One of the global diagnoses is a long clinical crown. An important strat- egy for correcting a long tooth is root coverage grafting. Gingival reces- sion is a common problem that is complicated by the loss of cervical tooth structure. It is always a difficult decision whether to graft or to re- store. This chapter provides a set of guidelines to help direct the decision- making process.
Tooth form is considered one of the most critical factors in esthetic dentistry, and gingival architecture impacts tooth form. Altered passive eruption reduces tooth length, while gingival recession increases tooth length. Placing restorations without first correcting these gingival abnormalities results in teeth that are either too short (in the case of altered passive eruption) or too long (in the presence of gingival recession). Fortunately, both of these gingival problems can be corrected surgically.
Root coverage with gingival grafting has been considered to be a predictable procedure for over 25 years and is routinely performed. When a patient is evaluated for restorative dentistry and recession is noted, a surgeon should be consulted prior to any restorative treatment to determine the need for gingival grafting and the degree of root coverage that can be expected. Complete root coverage is dependent upon the nature of the interdental bone and soft tissue. Miller described a classification system to serve as a guide for determining the outcome of root coverage grafting:
• Miller Class I: Recession does not extend to the mucogingival junction (MGJ), and there is no loss of interdental bone or soft tissue. Complete root coverage is expected (Fig 5-1a).
• Miller Class II: Recession extends to the MGJ, and there is no loss of interdental bone or soft tissue. Complete root coverage is expected (Fig 5-1b).
• Miller Class III: Recession extends to the MGJ, and there is some loss of interdental bone or soft tissue. Partial root coverage can be achieved (Fig 5-1c).
• Miller Class IV: Recession extends to the MGJ, and there is such severe loss of interdental bone and soft tissue that no root coverage can be achieved (Fig 5-1d).
Determining the proper treatment for cervical lesions presents a perplexing problem for both peri- odontists and restorative dentists because the tooth defect is usually accompanied by gingival recession. Cervical lesions are commonly seen in adult patients. These lesions may be asymptomatic, or they may present patient-related concerns including sensitivity, food retention, or esthetics. Resto- rations placed in or on root surfaces often lead to undesirable outcomes, especially in the absence of adequate marginal gingiva.
There are three types of cervical lesions: (1) noncarious cervical lesions, (2) restored cervical lesions, and (3) carious cervical lesions. Proper treatment of each of these types of cervical lesions may require placement of restorations, soft tissue grafting, or both surgical and restorative treatment.
Noncarious cervical lesions have multiple possible etiologies, including erosion or chemical agents, abrasion or physical agents (ie, aggressive tooth brushing), and abfraction or occlusal forces causing tooth flexure. Whatever the causes may be, they must be managed effectively if treatment is to be successful. Once the causative factors are determined and managed, five questions can be used to simplify the treatment-planning process for all three types of cervical lesions. All five questions must be answered before the final treatment decision is made.
The Five Questions
Question 1: Where is the cervical lesion located?
There are only three possibilities for location of the lesion: (1) on the crown only, (2) on the root only, or (3) on the crown and the root. The location of the lesion will obviously impact the treatment de- cision. If the lesion is on the root only or on the crown and the root, further assessment is needed before deciding whether to graft, restore, or both. If the lesion involves only the crown, the solution is a restoration. However, gingival grafting may also be indicated if the marginal gingiva is inadequate.
Question 2: What are the dimensions of the gingiva apical to the cervical lesion?
The marginal gingiva is an important, yet often overlooked feature when treating cervical lesions. All teeth require an adequate zone of marginal gingiva for function and comfort. While it is generally accepted that a minimum of 2 mm of gingiva (1 mm of attached gingiva and 1 mm of free gingiva) is necessary for health, more is desirable adjacent to restoration margins. Thus, assessment of four dimensions of gingiva must be made:
1. Total vertical dimension of gingiva
2. Vertical dimension of attached gingiva
3. Vertical dimension of free gingiva
4. Thickness of gingiva
The total vertical dimension of gingiva is determined by measuring the distance from the MGJ to the gingival crest. When the MGJ is not readily apparent, it can be found by gently displacing the mucosa coronally with a periodontal probe until it meets the attached gingiva. The mucosa will roll slightly at the MGJ and thus reveal this demarcation between the mucosa and the attached gingiva. Next, the sulcus is probed to determine how much of the gingiva is free gingiva. The vertical dimen- sion of free gingiva, the distance from the gingival crest to the base of the sulcus, is equal to the probing depth. The amount of attached gingiva is the total vertical dimension of gingiva minus the probing depth. The probing depth on the facial aspect ideally should be 1 to 2 mm, and there should be no bleeding on probing. Probing depth greater than 2 mm and/or bleeding on probing indicate a periodontal problem that requires additional periodontal evaluation and treatment. The gingival thickness is subjectively judged as thin, adequate, or thick. Ideally, the gingiva should be approximately 1 mm thick. Thin marginal gingiva is at risk for progressive recession, especially in the presence of existing recession or a cervical restoration.
If the dimensions of gingiva are found to be inadequate, gingival grafting is indicated whether a restoration is placed or not.
Question 3: What are the dimensions of the cervical lesion?
The dimensions of the cervical lesion will clearly impact the treatment decision. Both the horizontal depth toward the pulp and the vertical height of the lesion should be measured.
Grafting can successfully treat shallow cervical lesions (1 mm or less) involving the root only (Fig 5-2). If an existing shallow restoration or shallow carious lesion is present, grafting can be performed follow- ing removal of the restoration or the carious portion of the root (Fig 5-3). The root is simply reshaped to remove any sharp margins and to create a uniform surface for graft adaptation.
For moderately deep cervical lesions (less than 2 mm), the cervical enamel may be beveled and polished to reduce any potential undercut or minor enamel defect, and the root can be covered by a graft after root reshaping. The same is true for a moderately deep restoration or carious lesion.
A significantly deep lesion (at least 2 mm horizontally) would require excessive root reshaping in order to create a proper root form for coverage with a graft, especially where the vertical dimension of the cervical lesion is minimal. As the vertical dimension of the lesion increases, the possibility for grafting also increases because the amount of root reshaping diminishes. Thus, it is the geometric relationship of the horizontal and vertical dimensions of the lesion that directs the treatment decision toward a restoration, a graft, or both. In some sites, there may be a deep, V-shaped, horizontal cervical lesion with minimal vertical extent associated with significant root exposure apical to the true cervical lesion. In such a site, the cervical lesion should be restored and the remaining root exposure treated by grafting. The restoration should be limited to the true cervical lesion and not extend over the portion of the root that can be covered by the grafting procedure.
As the horizontal depth of the cervical lesion increases, the potential for crown involvement increases, and thus the potential need for a restoration also increases. Class V restorations may be required if the lesion is very deep or there is significant loss of anatomical crown form.
Question 4: How much root exposure is there?
The greater the amount of root exposure, the more likely it is that grafting will provide a significant benefit, especially in the esthetic zone. Shallow recession (less than 2 mm root exposure) in the pres- ence of adequate dimensions of gingiva rarely requires root coverage grafting except where esthetics or root sensitivity is a factor. However, it is desirable to cover roots where the recession is at least 3 mm.
Question 5: What is the classification of the recession?
Determination of the classification of recession is necessary to ascertain where gingival grafting will result in complete root coverage. Complete root coverage can routinely be achieved in sites with Mill- er Class I or Class II recession. For sites with Miller Class III or Class IV recession, complete root coverage is not possible. Partial root coverage can be achieved in Miller Class III sites, but no root coverage is expected in Miller Class IV sites.
It is necessary to assess the amount of root coverage that can be expected when deciding whether to graft or restore a cervical lesion on a root surface with Miller Class III recession. Generally, grafting procedures can cover a root to within 3 mm of the tip of the gingival papillae. A restoration should not be placed over the portion of the root that can be covered by a graft unless dictated by the depth of the cervical lesion. Restoration of cervical lesions should be secondary to placing the gingival level back to its ideal position.
Guidelines
Guidelines for treating cervical lesions based on these five questions are shown in Table 5-1. When all variables are in the Graft column, grafting is indicated, and when all variables are in the Restore column, placement of a restoration is indicated. However, often some variables will fall in each column (circled in red), leading to a decision to perform both grafting and restorative procedures. In this exam- ple (Fig 5-4a), review of the five variables reveals that:
• The cervical lesion is on the root, indicating a preference for a graft.
• The dimensions of marginal gingiva are inadequate, indicating the need for a graft.
• The depth of the cervical lesion is greater than 2 mm, suggesting that the cervical lesion should be restored.
• There is significant root exposure indicating root coverage grafting. The recession is Miller Class III or IV, meaning that complete root coverage is not possible
These findings indicate the need for a graft due to the inadequate dimensions of marginal gingi- va. There is also significant root exposure, but the recession is Miller Class III or IV, so complete root coverage is not possible. Because the cervical lesion is deep, a restoration should be considered. Figures 5-4b and 5-4c show the treatment and results.
When it is necessary to both graft and restore a cervical lesion, it is preferable to graft first because the outcome can be more precise when the restoration is placed after the root coverage surgery. In a non-esthetic area, the restoration may be placed first while leaving the root exposed for coverage with the grafting procedure. A graft can predictably cover a root to within 3 mm of the adjacent papilla tips. If there is a difference between the mesial and distal papilla heights, the shorter of the two papillae will determine the level of root coverage. Thus, ideally a restoration should not extend more than 3 mm apically from the papilla tip, leaving the rest of the root exposed for root coverage grafting.
Soft Tissue Grafting Technique
Surgical techniques for predictable root coverage grafting were first described more than 25 years ago. Earlier grafting procedures, such as the free gingival graft, were used primarily for augmenting sites with insufficient marginal gingiva, but coverage of exposed roots was not predictable prior to the introduction of the subepithelial connective tissue graft (CTG) technique. Not only did the CTG provide a predictable method for root coverage, but it also introduced a more comfortable internal harvesting method for obtaining palatal donor tissue.
Currently, root coverage grafting can be accomplished with a minimally invasive tunnel technique using an allograft or palatal donor tissue. An allograft results in predictable root coverage and an increase in marginal gingival thickness equivalent to the CTG, and multiple teeth can be treated in one visit without concern for the amount of palatal tissue available. The tunnel technique has been demonstrated to be more comfortable for the patient than flap procedures.
The recipient site is prepared with an intrasulcular approach without surface incisions, followed by placement of an allograft within a pouch and coronal advancement of the graft and pouch (Fig 5-5). The site preparation begins with an intrasulcular incision made with an End-Cutting Intrasulcular Knife (Hu-Friedy), followed by a subperiosteal blunt reflection with an Allen Microsurgical Elevator (Hu- Friedy). The papilla is elevated from the interdental crest with a Younger-Good 7/8 curette.
After mobilization of the marginal tissue, root preparation is performed with curettes and/or an ultrasonic instrument with a safe-sided diamond tip (Varios 750, Brasseler USA) to remove shallow restorations, to eliminate any angular portions of the lesion, and to create a uniform root surface with- out damaging the soft tissue. Ethylenediaminetetraacetic acid (EDTA) is applied to the root surface to remove the smear layer. If there is an enamel overhang coronal to the cervical lesion, it may be beveled and polished.
The next step is apical extension and mobilization of the pouch by sharp dissection using a Modi- fied Orban Knife (Hu-Friedy). This instrument will allow dissection that is immediately supraperiosteal to ensure passive advancement of the pouch to the cementoenamel junction and to create space for the graft while maintaining an immobile recipient bed.
The reconstituted allograft is trimmed to the proper dimensions and soaked in a platelet-rich plas- ma preparation for enrichment with growth factors. Alternatively, a CTG may be harvested from the palate. The graft is inserted into the pouch and aligned level with the gingival margins of the pouch. The graft and pouch are then coronally advanced simultaneously with a single subpapillary 6-0 poly- propylene continuous sling suture.
Typically, gain of keratinized tissue is minimal with a submerged grafting technique whether an allograft or a CTG is used.9,11 Realistically, gain of keratinized tissue is a rather meaningless parameter for submerged grafts. While gain of keratinized tissue is useful for assessing graft success for surface grafts such as free gingival grafts, the amount of keratinized tissue on the surface is not reflective of the gain of functional, dense, collagenous connective tissue with submerged grafts. The small gain of keratinized tissue following a submerged grafting technique is reflective of initial graft exposure and secondary retraction of the overlying tissue exposing a small portion of the graft, and it is not an indicator of graft success.
The advantages of this minimally invasive grafting technique include the following:
• No surface incisions, and thus no scarring
• Use of an allograft eliminating the need for a palatal donor site
• Reduced patient discomfort
• Greater acceptance of treatment
• Ideal esthetics
Palatal grafts are also very effective for predictable root coverage; however, they are subject to en- largement, thereby negatively impacting the esthetic outcome. Graft enlargement may be desirable in some alveolar ridge or papilla augmentation procedures, and thus palatal connective tissue may be a better choice for these applications. In sites where the graft cannot be completely covered, palatal tissue will perform better than an allograft.
Summary
Soft tissue grafting is an integral part of treatment of cervical lesions due to the root exposure and lack of adequate attached gingiva often associated with these lesions. Complete root coverage is a predictable outcome for Miller Class I and Class II recession defects, and partial root coverage can be achieved in Miller Class III defects. In the esthetic zone, it is desirable to cover as much of the root as possible, and all sites require an adequate zone of attached gingiva, especially adjacent to a restoration. Restorations are required for cervical lesions with excessive depth and significant involvement of the enamel, but they should be avoided where the lesion is shallow and the enamel involvement is minimal. Of course, some sites will require both soft tissue grafting and placement of a restoration. An interdisciplinary approach to treating cervical lesions will create the most biologically appropriate, stable, and esthetic outcome. Establishing the appropriate tooth form will determine the gingival level and extent of surgical procedures necessary to achieve the desired outcome.
Root coverage with gingival grafting has been considered to be a predictable procedure for over 25 years and is routinely performed. When a patient is evaluated for restorative dentistry and recession is noted, a surgeon should be consulted prior to any restorative treatment to determine the need for gingival grafting and the degree of root coverage that can be expected. Complete root coverage is dependent upon the nature of the interdental bone and soft tissue. Miller described a classification system to serve as a guide for determining the outcome of root coverage grafting:
• Miller Class I: Recession does not extend to the mucogingival junction (MGJ), and there is no loss of interdental bone or soft tissue. Complete root coverage is expected (Fig 5-1a).
• Miller Class II: Recession extends to the MGJ, and there is no loss of interdental bone or soft tissue. Complete root coverage is expected (Fig 5-1b).
• Miller Class III: Recession extends to the MGJ, and there is some loss of interdental bone or soft tissue. Partial root coverage can be achieved (Fig 5-1c).
• Miller Class IV: Recession extends to the MGJ, and there is such severe loss of interdental bone and soft tissue that no root coverage can be achieved (Fig 5-1d).
Determining the proper treatment for cervical lesions presents a perplexing problem for both peri- odontists and restorative dentists because the tooth defect is usually accompanied by gingival recession. Cervical lesions are commonly seen in adult patients. These lesions may be asymptomatic, or they may present patient-related concerns including sensitivity, food retention, or esthetics. Resto- rations placed in or on root surfaces often lead to undesirable outcomes, especially in the absence of adequate marginal gingiva.
There are three types of cervical lesions: (1) noncarious cervical lesions, (2) restored cervical lesions, and (3) carious cervical lesions. Proper treatment of each of these types of cervical lesions may require placement of restorations, soft tissue grafting, or both surgical and restorative treatment.
Noncarious cervical lesions have multiple possible etiologies, including erosion or chemical agents, abrasion or physical agents (ie, aggressive tooth brushing), and abfraction or occlusal forces causing tooth flexure. Whatever the causes may be, they must be managed effectively if treatment is to be successful. Once the causative factors are determined and managed, five questions can be used to simplify the treatment-planning process for all three types of cervical lesions. All five questions must be answered before the final treatment decision is made.
The Five Questions
Question 1: Where is the cervical lesion located?
There are only three possibilities for location of the lesion: (1) on the crown only, (2) on the root only, or (3) on the crown and the root. The location of the lesion will obviously impact the treatment de- cision. If the lesion is on the root only or on the crown and the root, further assessment is needed before deciding whether to graft, restore, or both. If the lesion involves only the crown, the solution is a restoration. However, gingival grafting may also be indicated if the marginal gingiva is inadequate.
Question 2: What are the dimensions of the gingiva apical to the cervical lesion?
The marginal gingiva is an important, yet often overlooked feature when treating cervical lesions. All teeth require an adequate zone of marginal gingiva for function and comfort. While it is generally accepted that a minimum of 2 mm of gingiva (1 mm of attached gingiva and 1 mm of free gingiva) is necessary for health, more is desirable adjacent to restoration margins. Thus, assessment of four dimensions of gingiva must be made:
1. Total vertical dimension of gingiva
2. Vertical dimension of attached gingiva
3. Vertical dimension of free gingiva
4. Thickness of gingiva
The total vertical dimension of gingiva is determined by measuring the distance from the MGJ to the gingival crest. When the MGJ is not readily apparent, it can be found by gently displacing the mucosa coronally with a periodontal probe until it meets the attached gingiva. The mucosa will roll slightly at the MGJ and thus reveal this demarcation between the mucosa and the attached gingiva. Next, the sulcus is probed to determine how much of the gingiva is free gingiva. The vertical dimen- sion of free gingiva, the distance from the gingival crest to the base of the sulcus, is equal to the probing depth. The amount of attached gingiva is the total vertical dimension of gingiva minus the probing depth. The probing depth on the facial aspect ideally should be 1 to 2 mm, and there should be no bleeding on probing. Probing depth greater than 2 mm and/or bleeding on probing indicate a periodontal problem that requires additional periodontal evaluation and treatment. The gingival thickness is subjectively judged as thin, adequate, or thick. Ideally, the gingiva should be approximately 1 mm thick. Thin marginal gingiva is at risk for progressive recession, especially in the presence of existing recession or a cervical restoration.
If the dimensions of gingiva are found to be inadequate, gingival grafting is indicated whether a restoration is placed or not.
Question 3: What are the dimensions of the cervical lesion?
The dimensions of the cervical lesion will clearly impact the treatment decision. Both the horizontal depth toward the pulp and the vertical height of the lesion should be measured.
Grafting can successfully treat shallow cervical lesions (1 mm or less) involving the root only (Fig 5-2). If an existing shallow restoration or shallow carious lesion is present, grafting can be performed follow- ing removal of the restoration or the carious portion of the root (Fig 5-3). The root is simply reshaped to remove any sharp margins and to create a uniform surface for graft adaptation.
For moderately deep cervical lesions (less than 2 mm), the cervical enamel may be beveled and polished to reduce any potential undercut or minor enamel defect, and the root can be covered by a graft after root reshaping. The same is true for a moderately deep restoration or carious lesion.
A significantly deep lesion (at least 2 mm horizontally) would require excessive root reshaping in order to create a proper root form for coverage with a graft, especially where the vertical dimension of the cervical lesion is minimal. As the vertical dimension of the lesion increases, the possibility for grafting also increases because the amount of root reshaping diminishes. Thus, it is the geometric relationship of the horizontal and vertical dimensions of the lesion that directs the treatment decision toward a restoration, a graft, or both. In some sites, there may be a deep, V-shaped, horizontal cervical lesion with minimal vertical extent associated with significant root exposure apical to the true cervical lesion. In such a site, the cervical lesion should be restored and the remaining root exposure treated by grafting. The restoration should be limited to the true cervical lesion and not extend over the portion of the root that can be covered by the grafting procedure.
As the horizontal depth of the cervical lesion increases, the potential for crown involvement increases, and thus the potential need for a restoration also increases. Class V restorations may be required if the lesion is very deep or there is significant loss of anatomical crown form.
Question 4: How much root exposure is there?
The greater the amount of root exposure, the more likely it is that grafting will provide a significant benefit, especially in the esthetic zone. Shallow recession (less than 2 mm root exposure) in the pres- ence of adequate dimensions of gingiva rarely requires root coverage grafting except where esthetics or root sensitivity is a factor. However, it is desirable to cover roots where the recession is at least 3 mm.
Question 5: What is the classification of the recession?
Determination of the classification of recession is necessary to ascertain where gingival grafting will result in complete root coverage. Complete root coverage can routinely be achieved in sites with Mill- er Class I or Class II recession. For sites with Miller Class III or Class IV recession, complete root coverage is not possible. Partial root coverage can be achieved in Miller Class III sites, but no root coverage is expected in Miller Class IV sites.
It is necessary to assess the amount of root coverage that can be expected when deciding whether to graft or restore a cervical lesion on a root surface with Miller Class III recession. Generally, grafting procedures can cover a root to within 3 mm of the tip of the gingival papillae. A restoration should not be placed over the portion of the root that can be covered by a graft unless dictated by the depth of the cervical lesion. Restoration of cervical lesions should be secondary to placing the gingival level back to its ideal position.
Guidelines
Guidelines for treating cervical lesions based on these five questions are shown in Table 5-1. When all variables are in the Graft column, grafting is indicated, and when all variables are in the Restore column, placement of a restoration is indicated. However, often some variables will fall in each column (circled in red), leading to a decision to perform both grafting and restorative procedures. In this exam- ple (Fig 5-4a), review of the five variables reveals that:
• The cervical lesion is on the root, indicating a preference for a graft.
• The dimensions of marginal gingiva are inadequate, indicating the need for a graft.
• The depth of the cervical lesion is greater than 2 mm, suggesting that the cervical lesion should be restored.
• There is significant root exposure indicating root coverage grafting. The recession is Miller Class III or IV, meaning that complete root coverage is not possible
These findings indicate the need for a graft due to the inadequate dimensions of marginal gingi- va. There is also significant root exposure, but the recession is Miller Class III or IV, so complete root coverage is not possible. Because the cervical lesion is deep, a restoration should be considered. Figures 5-4b and 5-4c show the treatment and results.
When it is necessary to both graft and restore a cervical lesion, it is preferable to graft first because the outcome can be more precise when the restoration is placed after the root coverage surgery. In a non-esthetic area, the restoration may be placed first while leaving the root exposed for coverage with the grafting procedure. A graft can predictably cover a root to within 3 mm of the adjacent papilla tips. If there is a difference between the mesial and distal papilla heights, the shorter of the two papillae will determine the level of root coverage. Thus, ideally a restoration should not extend more than 3 mm apically from the papilla tip, leaving the rest of the root exposed for root coverage grafting.
Soft Tissue Grafting Technique
Surgical techniques for predictable root coverage grafting were first described more than 25 years ago. Earlier grafting procedures, such as the free gingival graft, were used primarily for augmenting sites with insufficient marginal gingiva, but coverage of exposed roots was not predictable prior to the introduction of the subepithelial connective tissue graft (CTG) technique. Not only did the CTG provide a predictable method for root coverage, but it also introduced a more comfortable internal harvesting method for obtaining palatal donor tissue.
Currently, root coverage grafting can be accomplished with a minimally invasive tunnel technique using an allograft or palatal donor tissue. An allograft results in predictable root coverage and an increase in marginal gingival thickness equivalent to the CTG, and multiple teeth can be treated in one visit without concern for the amount of palatal tissue available. The tunnel technique has been demonstrated to be more comfortable for the patient than flap procedures.
The recipient site is prepared with an intrasulcular approach without surface incisions, followed by placement of an allograft within a pouch and coronal advancement of the graft and pouch (Fig 5-5). The site preparation begins with an intrasulcular incision made with an End-Cutting Intrasulcular Knife (Hu-Friedy), followed by a subperiosteal blunt reflection with an Allen Microsurgical Elevator (Hu- Friedy). The papilla is elevated from the interdental crest with a Younger-Good 7/8 curette.
After mobilization of the marginal tissue, root preparation is performed with curettes and/or an ultrasonic instrument with a safe-sided diamond tip (Varios 750, Brasseler USA) to remove shallow restorations, to eliminate any angular portions of the lesion, and to create a uniform root surface with- out damaging the soft tissue. Ethylenediaminetetraacetic acid (EDTA) is applied to the root surface to remove the smear layer. If there is an enamel overhang coronal to the cervical lesion, it may be beveled and polished.
The next step is apical extension and mobilization of the pouch by sharp dissection using a Modi- fied Orban Knife (Hu-Friedy). This instrument will allow dissection that is immediately supraperiosteal to ensure passive advancement of the pouch to the cementoenamel junction and to create space for the graft while maintaining an immobile recipient bed.
The reconstituted allograft is trimmed to the proper dimensions and soaked in a platelet-rich plas- ma preparation for enrichment with growth factors. Alternatively, a CTG may be harvested from the palate. The graft is inserted into the pouch and aligned level with the gingival margins of the pouch. The graft and pouch are then coronally advanced simultaneously with a single subpapillary 6-0 poly- propylene continuous sling suture.
Typically, gain of keratinized tissue is minimal with a submerged grafting technique whether an allograft or a CTG is used.9,11 Realistically, gain of keratinized tissue is a rather meaningless parameter for submerged grafts. While gain of keratinized tissue is useful for assessing graft success for surface grafts such as free gingival grafts, the amount of keratinized tissue on the surface is not reflective of the gain of functional, dense, collagenous connective tissue with submerged grafts. The small gain of keratinized tissue following a submerged grafting technique is reflective of initial graft exposure and secondary retraction of the overlying tissue exposing a small portion of the graft, and it is not an indicator of graft success.
The advantages of this minimally invasive grafting technique include the following:
• No surface incisions, and thus no scarring
• Use of an allograft eliminating the need for a palatal donor site
• Reduced patient discomfort
• Greater acceptance of treatment
• Ideal esthetics
Palatal grafts are also very effective for predictable root coverage; however, they are subject to en- largement, thereby negatively impacting the esthetic outcome. Graft enlargement may be desirable in some alveolar ridge or papilla augmentation procedures, and thus palatal connective tissue may be a better choice for these applications. In sites where the graft cannot be completely covered, palatal tissue will perform better than an allograft.
Summary
Soft tissue grafting is an integral part of treatment of cervical lesions due to the root exposure and lack of adequate attached gingiva often associated with these lesions. Complete root coverage is a predictable outcome for Miller Class I and Class II recession defects, and partial root coverage can be achieved in Miller Class III defects. In the esthetic zone, it is desirable to cover as much of the root as possible, and all sites require an adequate zone of attached gingiva, especially adjacent to a restoration. Restorations are required for cervical lesions with excessive depth and significant involvement of the enamel, but they should be avoided where the lesion is shallow and the enamel involvement is minimal. Of course, some sites will require both soft tissue grafting and placement of a restoration. An interdisciplinary approach to treating cervical lesions will create the most biologically appropriate, stable, and esthetic outcome. Establishing the appropriate tooth form will determine the gingival level and extent of surgical procedures necessary to achieve the desired outcome.
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