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 Table of Contents  
REVIEW ARTICLE
Year : 2017  |  Volume : 9  |  Issue : 1  |  Page : 52-59

Classification systems of gingival recession: An update


Department of Periodontology, Guru Nanak Dev Dental College and Research Institute, Sunam, Punjab, India

Date of Web Publication6-Mar-2017

Correspondence Address:
Ridhi Aggarwal
D/O Mr. Satya Nand Aggarwal Advocate, Old Tehsil Road, Phillaur, Jalandhar, Punjab
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0976-4003.201632

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  Abstract 

Gingival recession is defined as “the displacement of marginal tissue apical to the cementoenamel junction (CEJ)”. Various classifications have been proposed to classify gingival recession. Miller's classification of gingival recession is most widely followed. With a wide array of cases in daily clinical practice, it is often difficult to classify numerous gingival recession cases according to defined criteria of the present classification systems. This article outlines the limitations of present classification systems and also the new classifications that have been proposed to classify gingival recession.

Keywords: Cementoenamel junction, classification, gingival recession, interdental papilla, mucogingival junction


How to cite this article:
Jain S, Kaur H, Aggarwal R. Classification systems of gingival recession: An update. Indian J Dent Sci 2017;9:52-9

How to cite this URL:
Jain S, Kaur H, Aggarwal R. Classification systems of gingival recession: An update. Indian J Dent Sci [serial online] 2017 [cited 2019 Mar 25];9:52-9. Available from: http://www.ijds.in/text.asp?2017/9/1/52/201632


  Introduction Top


Gingival recession is defined as “the displacement of marginal tissue apical to the cementoenamel junction (CEJ)”. To categorize gingival recession, various classifications have been proposed. Most of the classifications of gingival recession are unable to convey all the relevant information related to marginal tissue recession. This information is important not only for shaping diagnosis, prognosis, and treatment planning but also communication between clinicians. Furthermore, with a broad variety of cases with different clinical presentations, it is not always possible to classify all gingival recession defects according to one classification system.

Classifications, defined as “systematic arrangements in groups or categories according to established criteria” (Merriam-Webster 2010), have been conceived to facilitate the comprehension of the great amount of factors and information involved in complex systems.[1]

Several classifications have been proposed in literature to facilitate the diagnosis of gingival recessions.[1] They are as follows:

  • Sullivan and Atkins (1968)
  • Mlinek (1973)
  • Liu and Solt (1980)
  • Bengue (1983)
  • Miller (1985)
  • Smith (1990)
  • Nordland and Tarnow (1998)
  • Mahajan (2010)
  • Cairo et al. (2011)
  • Rotundo et al. (2011)
  • Ashish Kumar and Masamatti (2013)
  • Prashant et al. (2014).


One of the first classifications to be proposed was by Sullivan and Atkins in 1968. The basis of this classification system was the depth and width of the defect. He proposed following four categories:[2]

  1. Deep wide
  2. Shallow wide
  3. Deep narrow
  4. Shallow narrow.



  Critical Evaluation Top


This classification though simple is subjected to open interpretation of the examiner and interexaminer variability and is therefore not reproducible.

Mlinek et al. (1973)

  • Shallow narrow: Recession <3 mm
  • Deep wide: Recession >3 mm.


This modification reduced subjective variation, but it does not specify the landmark for horizontal measurement as variable measurement may be present at variable distances.

Liu and Solt (1980) classified marginal tissue recession

  1. Visual: Measured from CEJ to soft tissue margin
  2. Hidden: 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.[3] This classification is not informative and does not classify visible recession, the focus being more on attachment loss than visible recession.

Bengue et al. (1983) classified the recessions according to the coverage prognosis:[3]

  1. U-type - poor prognosis
  2. V-type - fair prognosis
  3. I-type - good prognosis.


Miller proposed a classification system in 1985 and is probably still most widely used system for describing the gingival recession. He has primarily based his classification of gingival recession defects on following aspects:

  1. Extent of gingival recession defects
  2. Extent of hard and soft tissue loss in interdental areas surrounding the gingival recession defects.[4],[5]


Its significance lies in the fact that it is useful in predicting the final amount of root coverage following a free gingival graft procedure.[1]

Four types of recession defects were categorized as follow [Figure 1]:[1]
Figure 1: Millers classification. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

Click here to view


  • Class I: Marginal tissue recession, which does not extend to the mucogingival junction (MGJ). There is no periodontal loss (bone or soft tissue) in the interdental area, and 100% root coverage can be anticipated
  • Class II: Marginal tissue recession, which extends to or beyond the MGJ. There is no periodontal loss (bone or soft tissue) in the interdental area, and 100% root coverage can be anticipated
  • Class III: Marginal tissue recession, which extends to or beyond the MGJ. Bone or soft tissue loss in the interdental area is present or there is a malpositioning of the teeth, which prevents the attempting of 100% of root coverage. Partial root coverage can be anticipated. The amount of root coverage can be determined presurgically using a periodontal probe
  • Class IV: Marginal tissue recession, which extends to or beyond the MGJ. The bone or soft tissue loss in the interdental area and/or malpositioning of teeth is so severe that root coverage cannot be anticipated.


Although Miller's classification has been used extensively, there are limitations that need to be considered:[2]

  1. The reference point for classification is MGJ. The difficulty in identifying the MGJ creates difficulties in the classification between Class I and II. There is no mention of presence of keratinized tissue
  2. In Miller's Class III and IV recession, the interdental bone or soft tissue loss is an important criterion to categorize the recessions. The amount and type of bone loss have not been specified. Mentioning Miller's Class III and IV does not exactly specify the level of interdental papilla and amount of loss. A clear picture of severity of recession is hard to project
  3. Class III and IV categories of Miller's classification stated that marginal tissue recession extends to or beyond the MGJ with the loss of interdental bone or soft tissue apical to the CEJ. The cases, which have interproximal bone loss and the marginal recession that does not extend to MGJ cannot be classified either in Class I because of interproximal bone or in Class III because the gingival margin does not extend to MGJ
  4. The difference between Classes III and IV is based on the position of the gingival margin of the two adjacent teeth. Class III and Class IV can be identified if there are adjacent teeth; however, in case of a missing adjacent tooth, there is no reference point and it is impossible to include this case in the Class III or Class IV
  5. Miller's classification does not specify facial (F) or lingual (L) involvement of the marginal tissue
  6. Recession of interdental papilla alone cannot be classified according to the Miller's classification. It requires the use of an additional classification system
  7. Classification of recession on palatal aspect is another area of concern. The difficulty of the applicability of Miller's criteria on the palatal aspect of the maxillary arch can be reasoned out to the fact that there is no MGJ on palatal aspect
  8. Miller's classification estimates the prognosis of root coverage following grafting procedure. Miller stated that 100% coverage can be anticipated in Class I and II recessions, partial root coverage in Class III, and no root coverage in Class IV.


Pini-Prato (2011) stated that anticipation of 100% root coverage does not mean that it will occur. Root coverage percentage ranging from 9% to 90% has been reported by different authors in Class I and II recessions using different techniques. Outcome of treatment may depend on other prognostic factors and categorization to predict the outcomes of root coverage in Classes I and II are not correct.

Smith (1990) proposed index of recession that consists of two digits separated by a dash. The first digit denotes the horizontal and the second digit denotes the vertical component of a site of recession.


  Horizontal Extent of Recession Top


  • Score 0 - No clinical evidence of root exposure
  • Score 1 - No clinical exposure of root exposure plus a subjective awareness of dentinal hypersensitivity in response to a 1 s air blast is reported, and/or there is clinically detectable exposure of the CEJ for up to 10% of the estimated mid-mesial to mid-distal distance
  • Score 2 - Horizontal exposure of the CEJ more than 10% but not exceeding 25% of the estimated mid-mesial to mid-distal distance
  • Score 3 - Exposure of the CEJ more than 25% of the mid-mesial to mid-distal distance but not exceeding 50%
  • Score 4 - Exposure of the CEJ more than 50% of the mid-mesial to mid-distal distance but not exceeding 75%
  • Score 5 - Exposure of the CEJ more than 75% of the mid-mesial to mid-distal distance up to 100%.



  Vertical Extent of Recession Top


  • Score 0 - No clinical evidence of root exposure
  • Score 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 mm vertically to the gingival margin
  • Score 2–8 - Root exposure 2–8 mm extending vertically from the CEJ to the base of the soft tissue defect
  • Score 9 - Root exposure more than 8 mm from the CEJ to the base of the soft tissue defect
  • Score * - An asterisk is present next to the second digit whenever the vertical component of the soft tissue defect encroaches into the MGJ or extends beyond it into alveolar mucosa; the absence of an asterisk implies either absence of MGJ involvement at the indexed site or its noninvolvement in the soft tissue defect.[3]


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. Furthermore, separate values can be assigned for multirooted 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.

Nordland WP and Tarnow DP in 1998 as quoted in Glover ME [6] developed a classification system for loss of papillary height. The system utilizes three identifiable landmarks: the interdental contact point, the facial apical extent of the CEJ, and the interproximal coronal extent of the CEJ.

Normal: Interdental papilla fills embrasure space to the apical extent of the interdental contact point/area.

  • Class I: The tip of the interdental papilla lies between the interdental contact point and the most coronal extent of the interproximal CEJ
  • Class II: The tip of the interdental papilla lies at or apical to the interproximal CEJ but coronal to the apical extent of the facial CEJ
  • Class III: The tip of the papilla lies level with or apical to the facial CEJ.


Mahajan proposed a modified classification of gingival recession in 2010 which is:[5]

  • Class I: Gingival recession defect not extending to the MGJ
  • Class II: Gingival recession defect extending to the MGJ/beyond it
  • Class III: Gingival recession defect 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
  • Class IV: Gingival recession defect with severe bone or soft tissue loss in the interdental area greater than cervical 1/3 of the root surface and/or severe malpositioning of the teeth.


Prognosis as per Mahajan's classification:[5]

  • Best: Class I and Class II with thick gingival profile
  • Good: Class I and Class II with thin gingival profile
  • Fair: Class III with thick gingival profile
  • Poor: Class III and Class IV with thin gingival profile.


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 II.

Cairo et al. (2011) classified gingival recession based on the assessment of CAL at both buccal and interproximal sites.

  • Recession Type 1: Gingival recession with no loss of interproximal attachment. Interproximal CEJ was clinically not detectable at both mesial and distal aspects of the tooth
  • Recession Type 2: 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)
  • Recession Type 3: 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).[7]


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 MGJ, which play a very important role and govern the choice of treatment procedure; and tooth malposition which greatly affects the treatment outcome.

Rotundo et al. (2011) classified gingival recession taking into consideration both soft and hard dental tissues. For this classification, specific taxonomic variables have been considered, and in particular, the amount of keratinized tissue (KT = 2 mm); the presence/absence of noncarious cervical lesion (NCCL), with a consequent unidentifiable CEJ; and the presence/absence of interproximal attachment loss.

Considering these variables, the following method of assessment is suggested:

  1. KT ≥2 mm
    • NCCL – absent
    • Interproximal attachment loss – absent.
  2. KT <2 mm
    • NCCL – present
    • Interproximal attachment loss – present.


As a consequence, the following classes may be identified within the population:
  • KT ≥2 mm – no NCCL – no interproximal attachment loss (AAA)
  • KT ≥2 mm – NCCL – no interproximal attachment loss (ABA)
  • KT ≥2 mm – no NCCL – interproximal attachment loss (AAB)
  • KT ≥2 mm – NCCL – interproximal attachment loss (ABB)
  • KT <2 mm – no NCCL – no interproximal attachment loss (BAA)
  • KT <2 mm – NCCL – no interproximal attachment loss (BBA)
  • KT <2 mm – no NCCL – interproximal attachment loss (BAB)
  • KT <2 mm – NCCL – interproximal attachment loss (BBB).[8]


A new classification system was proposed by Kumar and Masamatti in 2013 based on amalgamation of certain criteria of Miller's classification with the certain features of Nordland and Tarnow's classification. It can be applied for facial surfaces of maxillary teeth and facial and lingual surfaces of mandibular teeth. Interdental papilla recession can also be classified according to this new classification. Class I deals with marginal tissue recession with no loss of interdental bone or soft tissue. Class II and III deal with the loss of interdental bone/soft tissue with/without marginal tissue recession.[2]

  • Class I: There is no loss of interdental bone or soft tissue. This is subclassified into two categories:
    • Class IA: Gingival margin on F/L aspect lies apical to CEJ, but coronal to MGJ with attached gingiva present between marginal gingiva and MGJ [Figure 2]a
    • Class IB: Gingival margin on F/L aspect lies at or apical to MGJ with an absence of attached gingiva between marginal gingiva and MGJ [Figure 2]b.
Figure 2: Ashish Kumars' classification: (a) Schematic representation of Class IA. (b) Schematic representation of Class IB. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

Click here to view


Either of the subdivisions can be on F or L aspect or both (F and L).

  • Class II: The tip of the interdental papilla is located between the interdental contact point and the level of the CEJ midbuccally/midlingually. Interproximal bone loss is visible on the radiograph. This is subclassified into three categories:
    • Class IIA: There is no marginal tissue recession on F/L aspect [Figure 3]a
      Figure 3: (a) Schematic representation of Class IIA. (b) Schematic representation of Class IIB. (c) Schematic representation of Class IIC. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

      Click here to view
    • Class IIB: Gingival margin on F/L aspect lies apical to CEJ but coronal to MGJ with attached gingiva present between marginal gingiva and MGJ [Figure 3]b
    • Class IIC: Gingival margin on F/L aspect lies at or apical to MGJ with an absence of attached gingiva between marginal gingiva and MGJ.


Either of the subdivisions can be on F or L aspect or both (F and L) [Figure 3]c.

  • Class III: The tip of the interdental papilla is located at or apical to the level of the CEJ midbuccally/midlingually. Interproximal bone loss is visible on the radiograph. This is subclassified into two categories:
    • Class IIIA: Gingival margin on F/L aspect lies apical to CEJ, but coronal to MGJ with attached gingiva present between marginal gingiva and MGJ [Figure 4]a
      Figure 4: (a) Schematic representation of Class IIIA. (b) Schematic representation of Class IIIB. Palatal gingival recession. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

      Click here to view
    • Class IIIB: Gingival margin on F/L aspect lies at or apical to MGJ with an absence of attached gingiva between marginal gingiva and MGJ.


Either of the subdivisions can be on F or L aspect or both (F and L) [Figure 4]b.


  Classification of Palatal Gingival Recession Top


The position of interdental papilla remains the basis of classifying gingival recession on palatal aspect. The criteria of subclassifications have been modified to compensate for the absence of MGJ.[2]

Palatal recession-I

There is no loss of interdental bone or soft tissue. This is subclassified into two categories:

  • Palatal recession-IA (PR-IA): Marginal tissue recession ≤3 mm from CEJ [Figure 5]a
  • PR-IB: Marginal tissue recession >3 mm from CEJ [Figure 5]b.
Figure 5: Palatal gingival recession: (a) Schematic representation of palatal recessions (palatal recession-IA). (b) Schematic representation of palatal recession-IB. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

Click here to view


Palatal recession-II

The tip of the interdental papilla is located between the interdental contact point and the level of the CEJ midpalatally. Interproximal bone loss is visible on the radiograph. This is subclassified into two categories:[2]

  • PR-IIA: Marginal tissue recession ≤3 mm from CEJ [Figure 6]a
  • PR-IIB: Marginal tissue recession >3 mm from CEJ [Figure 6]b.
Figure 6: (a) Schematic representation of palatal recessions (palatal recession-IIA). (b) Schematic representation of palatal recession-IIB. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

Click here to view


Palatal recession-III

The tip of the interdental papilla is located at or apical to the level of the CEJ mid-palatally. Interproximal bone loss is visible on the radiograph. This is subclassified into two categories:[4]

  • PR-IIIA: Marginal tissue recession ≤3 mm from CEJ [Figure 7]a
  • PR-IIIB: Marginal tissue recession >3 mm from CEJ [Figure 7]b.
Figure 7: (a) Schematic representation of palatal recessions (palatal recession-IIIA). (b) Schematic representation of palatal recession-IIIB. (Reprinted with permission from Kumar A, Masamatti S (4). Copyright 2013 Journal of Indian Society of Periodontology).

Click here to view


Prashant et al. (2014) proposed a classification that describes the dental surface defects that are of paramount importance in diagnosing gingival recession areas which might help in selecting definite treatment approach.

The evaluation was performed on both frontal and lateral views using a ×4 magnification lens, a periodontal probe (PCP UNC 15), and a dental explorer. Two variables were considered: CEJ and cervical discrepancies. Considering the presence of the CEJ on the buccal surface, two classes were identified: Class A, identifiable CEJ on the entire buccal surface and Class B, unidentifiable CEJ totally or partially. Considering the presence of cervical discrepancies (step), measured with a periodontal probe perpendicular to the long axis of the tooth in the deepest point of the abrasion, two classes were identified: Class (+), presence of cervical step (>0.5 mm) involving the root or the crown and the root and Class (−), absence of cervical step as shown in [Table 1]. Therefore, a working classification identifies four different conditions as:
Table 1: Prashant B et al's classification

Click here to view



  Discussion Top


We acknowledge the contributions of various eminent researchers in this field, which has paved a pathway for the current endeavor. Diagnosis and classification form an important part of approach to any condition or disease. The already existing classifications have some shortcomings which have been discussed. Hence, an attempt is made to fill those lacunae by devising new classifications. Of all the earlier classifications, Miller's classification is still most widely used. It is based on morphological evaluation of injured periodontal tissues and could be useful in predicting final amount of root coverage.

Pini-Prato then critically evaluated the limitations of Miller's classification based on Murphy's criteria. Since no classification is complete until it is updated regularly, especially in the light of recent innovations and advancements. Hence, in view of the drawbacks associated with Miller's classification, Mahajan's classification was proposed in an attempt to emphasize the need to modify Miller's classification to make it more comprehensive and updated.[2]

Apart from the standard landmarks used by Miller, there was a need to consider interproximal CEJ and gingival recession on palatal surfaces of maxillary teeth, to make the classification more useful and comprehensive. Hence, a new classification for palatal gingival recession was proposed. The factors considered in palatal gingival recession are:

  1. Relation of the gingival margin to MGJ: It determines the remaining width of attached gingiva and also governs the selection of treatment procedure
  2. 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. By the inclusion of interdental papilla and proximal CEJ in this classification, it may be useful for interdental papilla reconstruction around natural teeth
  3. 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. It also dictates the need for orthodontic treatment (e.g., Miller's Class I with tooth malposition)
  4. 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, which is one of the most common problems patients seek dental assistance for. Root caries and dentin hypersensitivity can be addressed by other nonsurgical treatment modalities which have a favorable outcome.[5]


This classification for palatal gingival recession is useful and exhaustive as it accommodates all clinical conditions that could be encountered in our practice. For instance, certain situations such as 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 this system. Furthermore, gingival recession not extending up to MGJ, without interproximal soft tissue loss, but with tooth malposition can be classified according to this system. This system also exhibits disjointness as there is no overlap between any of the classes and simplicity as it is easy to apply. Furthermore, 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 interexaminer variability, and increasing reproducibility.

We understand that all the classifications have some inbuilt drawbacks and none of them can actually serve the whole purpose. Hence, we recommend that the classification system which is suitable for a particular case should be used.


  Conclusion Top


Although various classification systems are in use and each system has an advantage of its own. No classification system can be complete and everlasting; with time and its continual use, one realizes the advantages and disadvantages of each system. An attempt has been made to review almost all the systems so that more accurate and detailed clinical picture can be made out for wide variety of cases.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Pini Prato G. The Miller classification of gingival recession: limits and drawbacks. J Clin Periodontol 2011;38:243-5.  Back to cited text no. 1
    
2.
Kumar A and Masamatti SS. A new classification system for gingival and palatal recession. J Indian Soc Periodontol 2013;17:175-81.  Back to cited text no. 2
[PUBMED]  Medknow Journal  
3.
Reddy S, Kaul S, Prasad MGS, Agnihotri J, Amudha D, Kambali S. Gingival recession: A proposal for a new classification. Int J Dent Clinics 2012;4:32-6.   Back to cited text no. 3
    
4.
Goldstein M, Brayer L and Schwartz Z. A critical evaluation of methods for root coverage. Crit Rev Oral Biol Med 1996;7:87-98.  Back to cited text no. 4
    
5.
Mahajan A. Mahajan's Modification of the Miller's Classification for Gingival Recession. Dental Hypotheses 2010;1:45-9.  Back to cited text no. 5
    
6.
Glover ME. Periodontal Plastic and Esthetic Surgery. Periodontics Medicine, Surgery and Implants, 1st edition. Philadelphia, PA, USA: Elsevier-Mosby;2004:405-87.  Back to cited text no. 6
    
7.
Cairo F, Nieri M, Cincinelli S, Mervelt J and 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;38:661-6.   Back to cited text no. 7
    
8.
Rotundo R, Mori M, Bonaccini D and Baldi C. Intra and inter-rater agreement of a new classification system of gingival recession defects. Eur J Oral Implntol 2011;4:127-33.  Back to cited text no. 8
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
 
 
    Tables

  [Table 1]



 

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