Aesthetic Periodontal Therapy – Root Coverage
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Several factors were related to the etiology of gingival recession (Kassab and Cohen,
2003):
Aging
Anatomical factors that have been related to recession include fenestration and
dehiscence of the alveolar bone, abnormal tooth position in the arch, aberrant path of
eruption of
the tooth, individual tooth shapeand presence/lack of attached gingiva
Physiological factors may include the orthodontic movement of teeth to positions
outside the labial
or lingual alveolar plate, leading to dehiscence formation.
Various forms of trauma—such as vigorous toothbrushing, aberrant frenal
attachment, occlusal injury, operative procedures and tobacco chewing—have been
thought to play a role in the etiology of recession.
According to Miller (1985), recession defects can be classified into four groups taking
into consideration the anticipated root coverage that can be obtained:
Class I: Marginal tissue recession not extending to the mucogingival junction. No
loss of interdental bone or soft tissue.
Class II: Marginal tissue recession extends to or beyond the mucogingival junction.
No loss of interdental bone or soft tissue.
Class III: Marginal tissue recession extends to or beyond the mucogingival junction.
Loss of interdental bone. Interdental soft tissue is apical
to the cemento-enamel
junction, but coronal to the apical extent of the marginal tissue recession.
Class IV: Marginal tissue recession extends beyond the mucogingival junction. Loss
of interdental bone and to a level corresponding to the apical extent of the marginal
tissue recession.
While complete root coverage can be achieved in Class I and II type recession defects,
only partial coverage may be expected in recessions of Class III and IV.
However, this classification has some limitations (Bouchard et al., 2001):
The position of the tooth and the alveolar ridge are not taken into account.
Recessions in teeth in a labial position may require orthodontic treatment prior to
surgical procedures.
The size of the defect in both vertical and horizontal dimensions must be considered.
As
a rule of thumb, the literature classifies the defects as shallow (<3 mm), moderate
(3 to 5 mm) or deep (>5 mm). On average, clinical studies indicate a defect width of
4.5 mm. A 5-mm width should be viewed as wide. It is to be
assumed that the larger
the recession area, the less root coverage should be expected.
The residual depth of the vestibule also seems to be of importance for the selection of
procedures.
A new two-figure Index of Recession (IR) was described by Smith (1997). The
horizontal
component
- the first digit -
is expressed as a whole number value from the range
0-5 depending on what proportion of the CEJ is exposed, on either the facial or lingual
A. L. Dumitrescu, Liviu Zetu and Silvia Teslaru
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aspects of the tooth, between the mesial and distal midpoints (MM-MD distance)
approximally. The criteria are as follows:
0; no clinical evidence of root exposure
1: as 0, but a subjective awareness of dentinal hypersensitivity in response to a 1
second air blast is reported and/or there is clinically detectable exposure of the CEJ
for up to 10% of the estimated MM-MD distance: a slit like defect
2; horizontal exposure of the CEJ >I0% but not exceeding 25%
of the estimated
MM-MD distance
3: exposure of the CEJ >25% of the MM-MD distance but not exceeding 50%
4; exposure of the CEJ >50% of the MM-MD distance but not exceeding 75%
5: exposure of the CEJ >75'/o of the MM-MD distance up to 100%
Allocation of these codes does not imply that the extent of recession is equally dispersed
about the facial or lingual midpoints of the area of exposed roots.
The second digit
of the IR gives the vertical extent of recession measured in whole mm
on a range 0-9. The precise criteria proposed are as follows:
0: no clinical evidence of root exposure
1: as 0, but a subjective awareness of dentinal hypersensitivity is reported and/or there is
clinically detectable exposure of the CEJ not extending >1 mm vertically to the gingival
margin
2-8: root exposure 2-8 mm extending vertically from the CEJ to the base of the soft tissue
defect
9: root exposure>8 mm from the CEJ to the base of the soft tissue defect.
An asterisk is afixed to the second digit whenever the vertical component of the soft
tissue defect encroaches into the muco-gingival junction or extends beyond it into alveolar
mucosa. The absence of an asterisk thus implies either absence of muco-gingival junction at
the indexed site or its non-involvement in the soft tissue defect. The prefixed F (or L) denotes
whether gingival recession is facial {or lingual) to the involved root.
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