Recession is the recession of the gingiva (the gum surrounding the tooth in a collar shape) and the underlying alveolar bone (bony compartment of the tooth) with the result that part of the root surface of the tooth is exposed. It may be appropriate to perform surgical recession coverage for a variety of reasons.
Indications (areas of application)
The gums surrounding the teeth, known as the gingiva, are pale pink in color when healthy and free of inflammation, are firmly fused to the bony substrate in widths of up to 9 mm, and are therefore more accurately referred to as attached gingiva (synonyms: attached gingiva; keratinized gingiva; stippled gingiva). The light coloration results from the abundance of fibers and the relative lack of blood vessels in the tissue. The function of this tightly attached gingival “collar” is to protect the soft tissue-to-tooth junction, the gingival pocket, from injury, food impaction and subsequent inflammation. If the attached gingiva is not wide enough for a variety of reasons, chronic (permanent) inflammation can occur, resulting in recession. Causes of recession formation may include:
- Gingival width below 2 mm with the consequence of chronic inflammation as a recession trigger; Acute trauma (injury), e.g. by the toothbrush or with sharp-edged food can also have a triggering effect.
- Approach of lip or cheek frenulum at the gingival margin; For clarification serves the positive pull test according to Klickman: the papilla (triangular-shaped gingiva between two teeth) under tension at the relevant frenulum becomes anemic (white by blood emptiness), so the band approach consistently damages the gingival tissue.
- Thin gingiva
- Size mismatch between tooth and alveolar bone: if a tooth with a root projecting buccally (towards the cheek) sits in a relatively narrow alveolar process (part of the jaw where the tooth compartments = alveoli are located), this results in the root being covered with only a very thin bone lamella, possibly even with fenestration (lamella has a “window”, thus does not completely cover the root)
- Tooth malposition: if a tooth is rotated in the alveolar process, its diagonal requires more space in the bone; The consequence is also only a thin covering bone lamella
- Incorrect brushing technique: the patient erroneously brushes in the transverse direction (“scrubbing”), he thus repeatedly produces injuries to the gingival margin, as a result of which it becomes inflamed (brushing trauma). If this passes into periodontitis (inflammation of the periodontium, so first inflammation of Sharpey’s suspension fibers then also the bone), the path to recession is clear.
On this basis, the following indications for surgical recession coverage:
- Hypersensitive exposed tooth necks.
- Functional impairment
- Aesthetic impairment
- Root coverage as a caries prophylaxis: the dentin (dentine) exposed in the root area is significantly more susceptible to caries than enamel.
- Gingival width below 2 mm even with inflammation-free gingiva.
- Lip and cheek frenulum with positive tensile test according to Klickman.
- Brushing traumas (after correction of incorrect brushing technique).
- Thin buccal bone lamella
- Tender, thin gingiva, e.g. before crown restoration: since the risk of recession formation is significantly lower after surgical intervention, consideration can be given in advance of crowning to prophylactic thickening with a free connective tissue graft to be able to permanently hold the crown margin subgingivally (below the gingival margin). A sufficiently wide and thick gingiva is created.
- Recession development in the course of orthodontic tooth movements.
- Elimination of pockets that extend beyond the mucogingival boundary (between attached gingiva and mobile mucosa/mucosa)
The procedures
Regardless of the surgical procedure selected, existing inflammation must be eliminated in advance and the patient must be motivated to use proper brushing technique and regular recall (check-up). In addition, improper loading of the affected teeth should be eliminated or corrected. The goal of periodontal surgery for recession coverage is to cover the root surface as completely as possible and halt the recession progression.Nevertheless, this goal cannot be achieved in every case. Once loss of the papilla (soft tissue between the tooth crowns) or even complete loss of the attached gingiva has occurred, complete coverage is no longer possible. Also regardless of the procedure, a new connective tissue attachment (fixation) to the newly formed root cementum (thin layer of hard tissue covering the dentin/dentine in the root area) is achieved in every case. Among the possible procedures, the following have become established, for example:
I. Displacement flap (pedicled graft)
I.1. coronal displacement flap (according to Bernimoullin):
The prerequisite is an adequately attached gingiva of at least 3 mm apical to the recession (toward the root). The advantage of the procedure is an esthetic result and that several adjacent recessions can be covered simultaneously.
- Local anesthesia (local anesthesia).
- Cleaning and smoothing of the root surface (scaling and root planing).
- Surgical preparation of a trapezoidal flap that preserves the papillae and must be adapted in its apical extension to the length of the recession. The flap can be formed either as a split flap, in which the mucosa is dissected from the periosteum (bone skin), or, in the case of thin gingiva, as a mucoperiosteal flap (full mucosal flap), in which the periosteum is dissected from the bone.
- For mucoperiosteal flaps: Mobilization of the flap by periosteal slitting at the base of the flap, because periosteum can not be stretched and the root surface without this mobilization can not be covered by stretching the flap.
- Conditioning the root surface with an enamel matrix protein preparation: enamel matrix proteins promote new root cementum formation, prevent epithelial cell growth from the gingival sulcus (the periodontal pocket), and promote the release of growth factors important for periodontal regeneration
- Shifting the flap coronally (towards the tooth crown) into the prepared mucosal defect.
- Button sutures
- Aftercare: patient rinses twice daily with chlorhexidine digluconate as sole care of the surgical area and refrigerates the first few days. After seven days suture removal and after another two to three weeks chlorhexidine rinses. Recall (follow-up appointment); professional dental cleaning (PZR) to remove chlorhexidine discoloration.
I.2. lateral displacement flap (laterally positioned pedicled graft; rotational flap):
The technique is used for gingival widening and to cover individual recessions with good postoperative color matching. The prerequisite is sufficiently wide and thick gingiva on one side of the recession so that sufficient attached gingiva remains at the graft harvest site postoperatively.
- Local anesthesia (local anesthesia).
- Scaling and root planing
- Surgical preparation of the recipient site: the edges of the incision are beveled and thus freed from epithelium so that the future graft is supplied not only by its own blood vessels in the flap pedicle, but also from the blood vessels of the recipient site
- The attached gingiva in the area of the recession is removed
- Formation of a split flap lateral to the recession: the periosteum remains on the bone, only the mucosa (mucosa) is activated and swung laterally to the recipient site. The mucosa over the postoperatively exposed periosteum is secondarily regenerated. Arch-shaped incision; the width of the flap must be three times the width of the recession itself, as this is the only way to ensure blood supply to the flap
- Conditioning of the root surface (see I.1.).
- Stress-free coverage of the root surface; if necessary, relief cut at the base of the flap away from the recession.
- Fixation of the flap with single button sutures.
- Aftercare as I.1.
II. free connective tissue graft
The procedure is used in combination with a displacement flap when the displacement flap technique alone is expected to result in too thin gingiva as a postoperative finding. The tissue of the hard palate serves as the harvest site:
- Prepare the recipient site as in I.1. and I.2.
- Local anesthesia (local anesthesia) of the hard palate.
- Graft harvesting from the palate in the area from the 1st premolar to the 1st molar; incision parallel to the dental arch at a distance of less than 1 cm from the gingival margin; two incisions parallel to the tooth axis in the direction of the palatal bone with a distance of approx. 2mm.
- Removal of the graft
- Removal of glandular and fatty tissue
- Supply of the removal site, for example, with single button sutures.
- Grafting: the epithelialized edge of the graft, originally facing the oral cavity, is brought to coincide with the enamel-cement interface of the root surface to be covered; fixation to the tooth by looping suture
- The split flap prepared in the recipient area (see I.1. or I.2.) is folded over the connective tissue graft, adapted (carefully pressed on until bleeding stops) and fixed with button sutures
- Aftercare: no wound dressing; as I.1
.
III. free gingival graft
This procedure is mentioned only for completeness, because it has fallen into the background in recent years, as it has disadvantages compared to the connective tissue graft:
- It cannot be covered with a mucosal flap because its surface is epithelialized like the rest of the mucosa of the oral cavity. This makes blood supply during the healing phase problematic, as it can only be achieved by diffusion.
- The color match of the palatal mucosa to the natural gingiva is often unsatisfactory.
The free gingival graft is used in implant dentistry to create attached gingiva and is of therapeutic importance in this regard.
IV. Envelope technique
It is used for smaller recessions and also in combination with a free connective tissue graft:
- Local anesthesia (local anesthesia).
- Scaling and root planing
- Preparation of a split flap (according to Raetzke) or full flap without vertical incision. A gingival margin incision is made while preserving the papillae, then the flap is bluntly dissected off comparable to opening a bag
- Conditioning of the root surface as I.1.
- Removal of the connective tissue graft as in II.
- Insertion of the graft into the prepared “pouch”, with the epithelialized margin repositioned on the enamel-dentin interface
- Fixation with button sutures
- Aftercare as I.1.
V. Elimination of high-set ligaments
V.1. frenotomy: the frenulum (ligament) is simply cut under local anesthesia. Follow-up as in I.1. V.2. V-Y displacement, Z-plasty, frenectomy: the frenulum is detached at the gingival attachment site under local anesthesia (local anesthesia) and displaced while following a specific incision technique. Follow-up as in I.1
.
VI GTR (synonyms: guided tissue regeneration, guided tissue regeneration)
Intraoperatively inserted membranes are used to create an artificial barrier to spatially separate the slowly regenerating periodontal retentive apparatus from the much more rapidly regenerating epithelial cells of the gingival sulcus (the periodontal pocket). While in the early stages of this technique it was necessary to work with non-absorbable membranes, which required a second surgical procedure to remove them, resorbable membranes made of natural or synthetic materials are now available. The membrane technique can be used in conjunction with the bone regeneration procedures mentioned in I and II above when recession is accompanied by pocket-shaped bone loss.
