The aim of the present study is to evaluate, whether use of the modified free gingival graft (mod-FGG) technique improves treatment outcomes after surgical root coverage at mandibular incisors with gingival recession defects.

Gingival recession defects (GRD), defined as displacement of the gingival margin apical to the cemento-enamel junction, are frequent clinical findings in the general population.

The major indications for root coverage procedures are improved esthetics, reduction of root hypersensitivity and the increase of the dimensions of keratinized tissue in order to facilitate infection control and prevent further progression of gingival recession defects. Numerous surgical techniques for root coverage have been suggested, with different degrees of success as assessed by the proportion of complete root coverage. The scientific evidence has revealed that mandibular incisors were associated with the least favourable outcomes when compared to other teeth. The lower success rate and lower predictability of root coverage procedures at lower incisors, teeth with the highest frequency of GRDs, may be related to the unfavorable anatomic conditions including marginal frenum attachment, high muscle pull and a shallow vestibule. These features are frequently encountered in the anterior area of the mandible, while they are rare in the maxillary anterior region.

The so-called "Free Gingival Graft" (FGG) was shown to be the most effective procedure for gingival augmentation at sites with minimal amount of keratinized tissue. Great variability in terms of proportion of root coverage (range: 11% to 87%; mean: 63%) has been reported when applying this technique, however. One of the challenges may be the inadequate blood supply to the portion of the FGG placed on the exposed root surface. A modified version of the FGG technique (mod-FGG) has been proposed, aiming to improve the vascularity of the recipient site over the denuded root surface. However, there is to date no scientific evidence whether the mod-FGG provides better clinical results than the conventional FGG.

The hypothesis of the study is that the mod-FGG will improve predictability and treatment outcomes for root coverage at mandibular incisors.

Inclusion Criteria:

• Age ≥ 18 years
• Periodontally and systemically healthy
• Full-mouth plaque score and full-mouth bleeding score ≤ 20% (measured at four sites per tooth)
• Thin phenotype
• Probing pocket depth (PPD) ≤3 mm
• Absence of excessive tooth mobility
• Absence of cervical composite restorations or non-carious cervical lesions
• Shallow vestibule

Exclusion Criteria:

• Pregnancy
• Smoking
• Alcoholism
• Para-functional habits
• Poor oral hygiene
• Excessive crowding or misalignment of teeth

1 year