Aesthetic Periodontal Therapy – Root Coverage
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thick flat periodontium are usually characterized by being more bulbous and square in form.
Contact areas are located more apically and usually are broad inciso gingivally and
faciolingually. The interproximal papillae filling the space between the teeth terminate at the
contact areas, hence, a flat periodontium. When irritated by tooth preparation, impression
procedures, extraction, or other clinical techniques, this periodontium usually reacts with
inflammation, followed by migration of the junctional epithelium apically, with resultant
periodontal pocket formation or redundant tissue (Sanavi et al., 1998). Predicable soft and
hard tissue contour after healing following surgery and minimal ridge resorption occurs after
extractions (Kao et al., 2008).
The thin scalloped type of periodontium, on the other hand, is distinguished by a
pronounced disparity between the height on the direct facial and that found interproximally.
The underlying bone is usually thin on the facial with dehiscences and fenestrations
commonly found. Usually there is less attached masticatory mucosa, from both quantitative
and qualitative perspectives. In the thin scalloped periodontium, the tooth form is usually
more subtle and somewhat triangular. Contact areas are located more incisally and are small
incisogingivally and faciolingually. The cervical convexity is less prominent. Since the
contact areas are located more incisally, the interproximal papilla is also positioned more
incisally, hence, the scalloped form. Excessive irritation of this type of periodontium usually
leads to recession both facially and interproximally (Sanavi et al., 1998). In this gingival
biotype after surgery it is difficult to predict where tissue will heal and stabilize and extensive
ridge resorption in the apical and lingual direction usually occurs after extractions (Kao et al.,
2008).
Many methods have been proposed to measure gingival tissue thickness:
direct measurements (Greenberg et al., 1976)
probe transparency (DeRouck et al., 2009; Kan et al., 2003).
This evaluation was
based on the transparancy of the periodontal probe through the gingival margin while
probing the sulcus at the midfacial aspect of the examined tooth.
If the outline of the
underlying periodontal probe could be seen through the gingival,
it was categorized
as thin; if not, it was categorized as thick.
ultrasonic devices (Müller et al., 2000)
cone-beam computer tomography (CBCT) (Januário et al., 2008; Barriviera et al.,
2009; Fu et al., 2010).
The identification of the gingival biotype may be important in clinical practice since
differences in gingival and osseous architecture have been shown to exhibit a significant
impact on the outcomes of periodontal therapy (Claffey and Shanley., 1986; Anderegg et al.,
1995; Baldi et al., 1999), root coverage procedures (Huang et al., 2005; Hwang and Wang,
2006), orthodontic therapy (Wennström et al., 1990, 1996) and implants esthetics (Zigdon et
al., 2008; De Rouck et al., 2009; Evans and Chen, 2008; Romeo et al., 2008).
Hwang and Wang (2006) reviewed the current literature to verify the presence of any
association between gingival thickness and root coverage outcomes.Fifteen investigations
were included. All of these reported at least 0.7mm of flap thickness, although measurement
locations varied. Treatment modalities included coronally advanced flap, connective tissue
graft, and guided tissue regeneration with and without adjuncts. A significant moderate
A. L. Dumitrescu, Liviu Zetu and Silvia Teslaru
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correlation occurred between weighted flap thickness and weighted mean root coverage and
weighted complete root coverage (r = 0.646 and 0.454, respectively; weighted mean of
gingival thickness accounted for 41.7% of variability in weighted mean root coverage results
and a lesser proportion (20.7%) in weighted complete root coverage (Hwang and Wang,
2006).
The paradigm shift proposedby Kao et al. (2008) was that by taking into consideration
the gingival tissue biotype during treatment planning, more appropriate strategies for
periodontal management may be developed, resulting in more predictable treatment
outcomes.
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