RESEARCH REVIEW Gingival recession: a proposal for a new classification Shantipriya Reddy, Sanjay Kaul, Prasad M.G.S., Jaya Agnihotri, Amudha D., Soumya Kambali ABSTRACT An accurate diagnosis is often the first step towards development of a well formulated treatment plan, that when implemented leads to resolution of patient s problem. Diagnosis of a disease/condition is a label that captures in few words, the nature, severity and extent of the problem. The terminology used to describe a patient s condition according to any classification, should enable the clinician to develop a clear image of the clinical situation. The current classification for gingival recession, however do not fulfill this criteria. Hence, in this review an attempt has been made to overcome these drawbacks and devise a new classification for gingival recession. Key Words: Classification; Gingival Recession I N T E R N A T I O N A L J O U R N A L O F D E N T A L C L I N I C S 2 0 1 2 V o l u m e 4 I s s u e 1 IIntroduction Gingival recession is defined as location of the gingival margin apical to the cemento-enamel junction. 1 It can be caused by various etiologies like periodontal disease, trauma, tooth malposition, aberrant frenal attachment. 2 Although it is a commonly occurring condition, its multifaceted presentation with regard to morphological variations, extent and severity has intrigued many clinicians. Hence numerous classifications have been proposed for a better representation of its clinical appearance and treatment outcome. The earliest classification dates back to 1968 when Sullivan and Atkins, in a study associated with mandibular incisors, used descriptive terms-shallow-narrow, shallow- wide, deep-narrow, deep-wide. This classification, although simple, is subjected to open interpretation of the examiner and inter-examiner variability and is therefore not reproducible. 3,4 Mlinek et.al classified gingival recession into shallow narrow defects as less than 3mm in both dimensions, and deep wide defects as more than 3 mm in both dimensions. This modification reduced subjective variation. But it does not specify the landmark for horizontal measurement as variable measurement may be present at variable distances. 5 Liu and Salt classified marginal tissue recession as visual and hidden types. Visual recession is measured from CEJ to soft tissue margin. Hidden recession refers to loss of attachment within the pocket that is apical to tissue margin. This classification is not informative and does not classify visible recession, the focus being more on attachment loss than visible recession. 6 Miller proposed a classification based on morphological evaluation of injured periodontal tissues,(table 1) which could be useful in predicting final amount of root coverage following free gingival graft procedure. 7 It is most widely used of all classification systems. The drawbacks of Miller s classification have been enumerated by Pini Prato. 8 It does not accommodate all clinical presentations of gingival recession. For example, a tooth with gingival marginal tissue recession not extending till MGJ but with interdental soft and hard tissue loss and a tooth with palatal recession cannot be placed in any of the categories. Similarly a tooth with marginal tissue recession not extending up to MGJ but with tooth malposition cannot be placed in any of the categories. The difference between class III and class IV lies in the severity and extent of soft and hard tissue loss in the interdental area. But no definite criteria, to assess the severity of tissue destruction in interdental area has been given. 9 The Index of recession was introduced by Smith in 1990. 10 The index considered the involvement of facial and lingual surfaces, mucogingival junction (MGJ) and amount of horizontal and vertical component (in mm) (Table 2). The author proposed that in cases of extensive vertical component further horizontal component may be allotted at an intermediate distance between CEJ and base of the defect, which is not clearly specified. Also separate values can be assigned for multi-rooted teeth, which make it more complex. It may lead to overestimation of the condition as it utilizes subjective awareness of sensitivity. It is also difficult to detect the midpoints of mesial and distal surfaces, in the presence of intact interdental papilla. In 2010 Mahajan proposed a modification of Miller s classification 9 (Table 3). This modification still does not accommodate all clinical conditions. For example: A tooth with gingival recession not extending up to MGJ but with interdental soft and hard tissue loss can neither be placed in Class I nor in Class III since there is no mention of involvement of MGJ in Class III. Cairo et.al classified gingival recession using interproximal clinical attachment level and used it to predict root coverage outcomes (Table 4). 11 This classification provides a simplified method of categorizing gingival recession and also emphasizes the role of interproximal attachment level, one of the important site related prognostic factor. However, it does not consider the remaining width of attached gingiva, relationship of gingival margin and mucogingival junction, which play a very important role and govern the choice of treatment procedure; and tooth malposition which greatly affects the treatment outcome. 32
Gingival recession: Proposal for a new classification Thus, despite the multiple treatment options available and new ones being explored, the best outcome can only be expected with early diagnosis and prompt treatment. The step towards diagnosis would be incomplete without an inappropriate classification system. Hence, considering all these factors, we have attempted to develop a classification of gingival recession, keeping in mind the needs of a classification and Class I II III IV Score 0 No clinical evidence of root exposure 1 No clinical exposure of root exposure plus a subjective awareness of dentinal hypersensitivity is reported and/ or there is clinically detectable exposure of the CEJ not extending more than 1 millimeter vertically to the gingival margin 2-8 Root exposure 2 to 8 mm extending vertically from the CEJ to the base of the soft-tissue defect 9 Root exposure more than 8 mm from the CEJ to the base of the soft-tissue defect * An asterisk is present next to the second digit whenever the vertical component of the soft-tissue defect encroaches into the mucogingival junction or extends beyond it into alveolar mucosa; the absence of an asterisk implies either absence of mucogingival junction involvement at the indexed site or its noninvolvement in the soft-tissue defect Vertical extent of recession Classification Class I Class II Class III Class IV Marginal tissue recession that does not extend to the mucogingival junction Gingival recession defects (GRD) not extending to the MGJ GRD extending to the MGJ/beyond it. GRD with bone or soft-tissue loss in the interdental area up to cervical 1/3 of the root surface and/or malpositioning of the teeth. GRD with severe bone or soft tissue loss in the interdental area greater than cervical 1/3rd of the root surface and/or severe malpositioning of the teeth. Table 3: Mahajan s modification of Miller s classification 10 the critical factors to be considered to classify gingival recession. for proposed Classification of Gingival Recession. Taking into account the most critical factors that affect gingival recession, namely relation between the gingival margin and MGJ, status of the interdental hard and soft tissues, tooth mal- Marginal tissue recession that extends to or beyond the mucogingival junction, with no periodontal attachment loss (bone or soft tissue) in the interdental area Marginal tissue recession that extends to or beyond the mucogingival junction, with periodontal attachment loss in the interdental area or malpositioning of teeth Marginal tissue recession that extends to or beyond the mucogingival junction, with severe bone or soft-tissue loss in the interdental area and/or severe malpositioning of teeth Table 1: Miller s classification of marginal tissue recession.(1985) 8 Score 0 No clinical evidence of root exposure 1 No clinical exposure of root exposure plus a subjective awareness of dentinal hypersensitivity in response to a one-second air blast is reported, and/or there is clinically detectable exposure of the CEJ for up to 10 percent of the estimated mid-mesial to mid-distal distance 2 Horizontal exposure of the CEJ more than 10 percent but not exceeding 25 percent of the estimated mid-mesial to mid-distal distance 3 Exposure of the CEJ more than 25 percent of the mid-mesial to mid-distal distance but not exceeding 50 percent 4 Exposure of the CEJ more than 50 percent of the mid-mesial to mid-distal distance but not exceeding 75 percent 5 Exposure of the CEJ more than 75 percent of the mid-mesial to mid-distal distance up to 100 percent Table 2: Index of recession by Smith (1990) Horizontal extent of recession. 11 33
Reddy et al Class Recession Type 1 (RT1) Recession Type 2 (RT2) Recession Type 3 (RT3) Gingival recession with no loss of interproximal attachment. Interproximal CEJ was clinically not detectable at both mesial and distal aspects of the tooth Gingival recession associated with loss of interproximal attachment. The amount of interproximal attachment loss (measured from the interproximal CEJ to the depth of the interproximal pocket) was less than or equal to the buccal attachment loss (measured from the buccal CEJ to the depth of the buccal pocket) Gingival recession associated with loss of interproximal attachment. The amount of interproximal attachment loss (measured from the interproximal CEJ to the depth of the pocket) was higher than the buccal attachment loss (measured from the buccal CEJ to the depth of the buccal pocket) Table 4: Classification of gingival recession based on the assessment of CAL at buccal and interproximal sites 12 Class I- Marginal tissue recession does not extend up to mucogingival junction (Fig 1). Class I A- Marginal tissue recession does not extend up to mucogingival junction with loss of interdental soft tissue beyond the interproximal CEJ (Fig 2). Class I B -Associated with tooth malposition (Fig 3). Combined Class I -Includes both A & B components i.e., Marginal tissue recession does not extend up to mucogingival junction with loss of interdental soft tissue beyond the interproximal CEJ associated with tooth malposition (Fig 4). Class II-Marginal tissue recession extends up to or beyond mucogingival junction (Fig 5). Table 5: Proposed New Classification of Gingival Recession Class II A-Marginal tissue recession extends up to or beyond mucogingival junction, with loss of interdental soft tissue beyond the interproximal CEJ (Fig 6). Class II B-Associated with tooth malposition (Fig 7). Combined Class II-Includes both A & B components i.e., marginal tissue recession extends up to or beyond mucogingival junction with loss of interdental soft tissue beyond the interproximal CEJ associated with tooth malposition (Fig 8). Class III-Marginal tissue recession seen on palatal surfaces of maxillary teeth (Fig 9). - interproximal soft tissue loss is accompanied by underlying bone loss. Note- In cases where MGJ cannot be identified, gingival recession not extending/ extending into alveolar mucosa should be considered to designate Class I/ Class II. position, palatal gingival recession and gingival recession can be classified as follows [Table 5]. Discussion We acknowledge the contributions of various eminent researchers in this field, which has paved a pathway for the current endeavor. 3,4,6-11 Diagnosis and classification form an important part of approach to any condition or disease. The existing classifications have some shortcomings which have been discussed. Hence an attempt is made to fill those lacunae by devising a new classification. Apart from the standard landmarks used by Miller we have considered interproximal 34
Gingival recession: Proposal for a new classification CEJ, gingival recession on palatal surfaces of maxillary teeth, to make the classification more useful and comprehensive. The factors considered are, a) relation of the gingival margin to MGJ: It determines the remaining width of attached gingiva and also governs the selection of treatment procedure, b) height of the interdental papilla: It plays a very important role as the interdental papilla acts as the most coronal vascular bed to which the soft tissues covering the root exposure are anchored. 12 By the inclusion of interdental papilla and proximal CEJ in this classification, it may be useful for interdental papilla reconstruction around natural teeth. c) Tooth malposition: It is important to recognize these situations, as tooth malposition can impair complete root coverage; resulting in persistence of root exposure after surgery. 12 It also dictates the need for orthodontic treatment. (For eg.: Miller s Class I with tooth malposition), d) Palatal recession: Although palatal recessions do not pose any esthetic problem, they have to be considered as they may result in root caries and dentin hypersensitivity, 8 which is one of the most common problems patients seek dental assistance for. Root caries and dentin hypersensitivity can be addressed by other non-surgical treatment modalities which have a favorable outcome. Pini-Prato has critically evaluated the limitations of Miller s classification based on Murphy s criteria. 8 Based on that this review tried to overcome that. Our proposed classification is useful and exhaustive as it accommodates all clinical conditions that could be encountered in our practice. For instance certain situations like, gingival recession not extending up to MGJ, with interproximal soft and hard tissue loss; palatal recession, which could not be categorized in any of Miller s classes, can be classified according to the proposed system. Also gingival recession not extending upto MGJ, without interproximal soft tissue loss, but with tooth malposition can be classified according to this system (Class I B). This system also exhibits disjointness as there is no overlap between any of the classes & simplicity as it is easy to apply. Also it excludes gingival margins of adjacent teeth and thus can be applied to gingival recession adjacent to a missing tooth. This system gives clear, definite criteria for classification, thus minimizing multiple interpretations by different examiners, thereby reducing inter-examiner variability and increasing reproducibility. Therefore this system may prove to be reliable and valid. However, it needs to be validated by reliability studies for appropriate application in clinical practice. Ideally a classification should be useful to determine the etiology, diagnosis, prognosis, treatment of a disease/ condition. This classification is devised with a diagnostic perspective. MGJ is a constant structure and most of the times can be identified clinically. In cases where it cannot be identified clinically, other methods of identifying can be used. 11 When MGJ cannot be identified, gingival recession not extending/ extending into alveolar mucosa should be considered to designate Class I/ Class II. Interproximal soft tissue loss can be easily ascertained by visualizing the interproximal CEJ. Also, malposition can be easily identified. Gingival recession can be caused by wide number of factors- aging, anatomical, physiological, pathological factors. 5 Additionally, prognosis is affected by various tooth-related, patient-related, technique-related factors. It is practically impossible to include all these factors to provide a classification that is useful for etiology, prognosis, yet maintain simplicity. Thus, choices have to be made between all these factors and priority has to be given to most critical factors affecting gingival recession. The treatment cannot be determined using any classification because we have multiple treatment options at our disposal with varying predictability and outcomes. By proposing this novel classification for gingival recession, an attempt has been made to devise a comprehensive & simple classification that is easy to apply. As the history suggests that every new classification often faces initial resistance for acceptance by clinicians. Despite its very apparent flaws, once a classification has been learnt and accepted, clinicians are often reluctant to accept revisions, unless they are proposed by a scientific group/ committee. Nonetheless, this classification aims to overcome the drawbacks of previously proposed systems. Owing to the lucidity and simplicity of this newly proposed classification, it can be expected that it will be well accepted by the clinical and student fraternity in their day to day practice. Further this classification should be applied in longitudinal studies, to evaluate its practicality, reliability and validity. Acknowledgements We acknowledge the support of Post-graduate students, Department of Periodontics, Dr. Syamala Reddy Dental College, Hospital and Research Centre. The authors report no conflicts of interest. Authors Affiliations 1. Shantipriya Reddy MDS, Professor and Head, 2. Sanjay Kaul MDS, Associate Professor, 3. Prasad M.G.S MDS, Reader, 4. Jaya Agnihotri MDS, Senior Lecturer, 5. Amudha D. MDS, Senior Lecturer, 6. Soumya Kambali BDS, Post-graduate student, Department of Periodontics, Dr. Syamala Reddy Dental College, Hospital and Research Center, Bangalore, Karnataka, India. References 1. Wennström JL. Mucogingival therapy. Annals of periodontology. 1996;1(1):671-701. 2. Amran AG, Ataa MAS. Statistical analysis of the prevalence, severity and some possible etiologic factors of gingival recessions among the adult population of Thamar City, Yemen. RSBO. 2011;8(3):305-61. 3. Camargo PM, Melnick PR, Kenney EB. The use of free gingival grafts for aesthetic purposes. Periodontol 2000. 2001;27(1):72-96. 4. Sullivan H, Atkins J. Free autogenous gingival grafts. I. Principles of successful grafting. Periodontics. 1968;6(3):121-9. 5. Kassab MM, Cohen RE. The etiology and prevalence of gingival recession. The J Am Dentl Assoc. 2003;134(2):220-5. 35
Reddy et al 6. Liu W, Solt C. A surgical procedure for the treatment of localized gingival recession in conjunction with root surface citric acid conditioning. J Periodontol. 1980;51(9):505-19. 7. Miller Jr P. A classification of marginal tissue recession. Int J Periodontics Restorative Dent. 1985;5(2):8-13. 8. Pini-Prato G. The Miller classification of gingival recession: limits and drawbacks. J Clin Periodontol. 2011;38(3):243 5. 9. Mahajan A. Mahajan s Modification of the Miller s Classification for Gingival Recession. Dental Hypotheses. 2011;1(1):45 50. 10. Smith RG. Gingival recession Reappraisal of an enigmatic condition and a new index for monitoring. J of Clin Periodontol. 1997;24(3):201-5. 11. Cairo F, Nieri M, Cincinelli S, Mervelt J, Pagliaro U. The interproximal clinical attachment level to classify gingival recessions and predict root coverage outcomes: an explorative and reliability study. J Clin Periodontol. 2011;38(7):661-6. 12. Zucchelli G, Testori T, De Sanctis M. Clinical and anatomical factors limiting treatment outcomes of gingival recession: a new method to predetermine the line of root coverage. Periodontol. 2006;77(4):714-21. 13. Tarnow D. Clinical Periodontology and Implant Dentistry. 2009;18(2):101. How to cite this article Reddy S., Kaul S., M.G.S.P., Agnihotri J., D.A., Kambali S.: Gingival recession: Proposal for a new classification.int. J. Dent.Clinics. 2012;4(2): 32-36. Address for Correspondence Dr. Soumya Kambali BDS, C/O: Dr. Syamala Reddy Dental College, Munnekolala, Marathahalli, Bangalore- 560037 Karnataka, India. Email: soumyakambali@gmail.com Source of Support: Nil Conflict of Interest: None Declared 36