Vestibular frenectomy in periodontal plastic surgery

Vestibular frena are bands of soft tissue that connect the lip or cheek to the alveolar mucosa or to the gum and that can restrict their movements. These mucosal folds can, in some cases, attach too close to the teeth and are associated to a persistent diastema. Additionally, if this frenum is too tight, it can cause gum recession by pulling the gums away from the teeth. The position of a frenum can become more apical and be corrected during growth with anterior teeth eruption. However, when it causes self-con-sciousness, pain, or gum recession, a frenectomy is indicated. The frenectomy is a simple procedure which involves total surgical removal of a frenum. The presence of a hypertrophic maxillary vestibular medial frenum associated with a diastema is the most commonly encountered indication in children. Its elimination will contribute to diastema closure that will stay stable over time.

This classification can also be used to distinguish between the attachment of the lateral and the lingual frena. In 2011, a study with 226 children (mean age 8.5 years), in terms of maxillary median maxillary frenum attachment, 10.2% children had mucosal attachment, 41.6% had gingival attachment, 22.1% had papillary attachment, and 26.1% had interdental attachment 8 . In other words, 48.2% frena had attachment interfering with the sulcus. A gingival-mucosal frenum has a single attachment distributed over two or three attachment points 18 , and this is most commonly seen with the lateral frenum. A frenum is not responsible for periodontal pathology or the presence of a diastema. It can be considered as an associated unfavorable anatomical factor. They may represent    an anatomical anomaly of the gingiva and/or the alveolar mucosa 31 . For this reason, complete or partial removal of frena may be indicated for periodontal and/or orthodontic reasons.
The frenectomy must be part of the treatment plan for other defects or pathologies 29 . These include -limitation of tongue and lip movements; -orthodontic closure of a diastema; -purely esthetic indications; -gingival or periodontal recessions; -position on edentulous ridge that impedes the completion of a prosthesis; -associated lack keratinization; -mobile mucosa around implants; -periodontal disease linked to the presence of plaque and preventing the maintenance of hygiene.
Frenectomy may be performed for periodontal and orthodontic indications.

Periodontal Indications
Frenum exerting marginal gingiva traction and/or obstructing hygiene.
A "normal" frenum is attached a few millimeters from the marginal gingiva, delimiting a band of keratinized tissue and attached coronally to the frenum attachment. 17 A very large frenum can also simply prevent periodontal or even oral hygiene ( Fig. 2) because of its volume.
When this mucosal fold moves during the muscular movements for phonation, facial expressions, and chewing, the tissues to which it is attached are pulled.
If these tissues that frena are attached to are keratinized and attached to the gingiva, tissue movement will be absent. If, on the other hand, frena are attached to the free gingiva or if a periodontal lesion or recession has caused the tissues to migrate till the attachment, there will no longer be any keratinized tissue or attached gingiva 38 , resulting in the opening of a gingival sulcus or a periodontal pocket (Fig. 3).
If only the alveolar mucosa remains, maintaining good oral hygiene becomes difficult because it is painful, and gingival inflammation is likely to promote the progression of gingival recession (especially in children) 35 , or the formation of periodontal pockets.
Ramfjord 36 (1993) based the indication of frenectomy primarily on the possibility to maintain gingival health through proper hygiene. In these circumstances, frena are considered minor etiological factors in periodontal pathology and/or more effective etiological factors in mucogingival problems. 5 lateral frena frequently exert traction on the free gingiva and make the vestibule shallow, impeding the passage of the toothbrush.

INDICATIONS FOR VESTIBULAR FRENECTOMY
The traction exerted by the frenum on the marginal periodontium is harmful because it can: -open the gingivodental sulcus; -allow the accumulation of bacterial plaque 21 ; -interfere with hygiene (especially if there is no keratinized gingiva at all) 4 ; -apical traction on the tissues at the bordering an early recession; -tension on surgically displaced tissues.
This unfavorable clinical situation frequently encountered with Placek 32 type-3 and type-4 frena. Without intervention, the orofacial muscles of facial expression and the movement of the lips and cheeks can move the free gingiva.
In the presence of type-IV periodontium in Maynard and Wilson (1980) 23 classification, the situation represents an area of weakness.
The following associated clinical signs indicate a frenectomy: 27 -Whitening of the internal papilla or the free gingiva during traction; 11 -The limitation of labial or lingual movement (short and taut frenum); -The proximity of attachment to the free marginal gingiva; -The large width of the frenum at its attachment 13 ; -The opening of the gingivodental sulcus during traction.

Unesthetic frena
Elimination of unsightly frena has its place in the overall therapeutic arrangement of Class-1 and Class-2 malocclusions 22 and the treatment of gingival contour asymmetries (line of necks) 25 ( Fig. 4a and b).
In most cases, a simple movement of the frenum attachment is sufficient.  It must not leave a scar. Frenectomy will be esthtetically satisfactory more frequently when associated with a laterally positioned flap technique 24 or a gingival 5 graft to cover the excised site.

Frenum-related with periodontal pathology
During development of periodontitis and the evolution of a periodontal pocket, a frenum can become harmful by exerting traction on delicate tissues in the region of the pocket in question. However, it may not interfere when the periodontium is healthy. The mandibular frenum is associated with recessions in 5% patients studied by Bork and Weiler (1958) 6 , regardless of age.
The presence of a bulky frenum or frenum attached in the keratinized tissue may compromise the stability of postoperative periodontal tissue; periodontal treatment must involve tissue movement and impeccable postoperative immobility to treat the deep periodontium (guided tissue regeneration, induced tissue regeneration, bone filling, coronally positioned flap) or marginal periodontium (displaced flaps associated or not associated with connective tissue grafts, tunneling).
The frenum may simply be shifted apically, at least 15 days before the operation. In some cases, frenectomy is performed during surgical treatment (Fig. 5a, b, c, and d).

Orthodontic Indications
Hypertrophic median frenum and anterior superior diastema A hypertrophic median frenum may interfere with the orthodontic closure of certain diastemas ( Fig. 6a and b).
Even if the indications for frenectomy along with diastema closure are not common, it remains optional 33 . In many cases, interincisal diastemas close spontaneously 12,13,37 .
The spontaneous closure of diastemas depends on the action of three processes: -centripetal pressure exerted by the eruption of surrounding teeth, and in particular maxillary canines; -growth of the premaxilla; -contractile force of trans-septal interincisal fibers.
Thus, the presence of agenesis, an eruption, growth anomaly, and/or an interruption of the contractile fibers causes the diastema to persist. However, the indications for frenectomy associated with an orthodontic diastema closure is based on studies by Ewen and Pasternak (1964) 14 and James (1967) 19 . The first study showed that when restraint was removed after closure of    the interincisal diastema, the space was opened again. After a fresh diastema closure and frenectomy, when the restraint was removed, the space remained closed. James, on the other hand, selected 10 cases with a median diastema and complete and stable teeth in patients aged 12-22 years. One year after total frenectomy, diastema dimensions showed a decrease in eight patients, remained stable in one patient, and increased in the remaining patient.
In the presence of a diastema, frenectomy is indicated in the following situations: divergent or rotating central incisors; maxillary lateral incisor absent, the space between the central incisors must be closed before the fixed prosthesis; persistence of the diastema during retraction of the anterior block in Angle Class-II division 1; appearance of an interincisal diastema during orthodontic treatment (frequently associated with extraction of first premolars); absence of a central incisor whose therapeutic choice is to close space 19 .
Even if the indications for frenectomy along with diastema closure are not common, it remains optional. However, controversy exists regarding the most appropriate time in the treatment plan to intervene. For some, frenectomy should precede diastema closure 9 , the downside being the risk of causing very fibrous scar tissue or granulation tissue that will be an obstacle to orthodontic closure. Thus, for others, the diastema must first be closed and the frenectomy performed during orthodontic restraint 16,24 , if possible at the end of skeletal growth. Some cases have even shown a spontaneous closure of the diastema after the frenum removal 20 .
Delaire (1974) 10 recommends waiting until age 8 years to treat a maxillary frenum. This is because before that age, maxillary labial frenum, through its fibrous attachments at the interpremaxillary suture, represents a sutural disjunction factor and a growth factor under the influence of the traction of the upper labial muscles, and it is consequently an active expansion factor.
Depending on the criteria for bone growth, it would seem logical to intervene as late as possible. Indeed, the attachment height of a frenum depends in large part on the vertical development of alveolar processes 34 . A frenum may appear hyperplastic due to a lack of height of the alveolar structures 15 . It will therefore be necessary to take into account the patient's actual age, the eruption of the six anterior teeth, and also the alveolar bone development to determine the best time to intervene.
Depending on the type of frenum attachment, a frenotomy or frenectomy may be performed. Frenotomy will be sufficient to treat a superficial frenum attachment. Frenectomy will treat a deep periosteal frenum attachment and may remove a frenum attached into the intermaxillary suture.

OPERATIVE TECHNIQUES OF THE VESTIBULAR FRENECTOMY 26
Frenotomy leaves a periosteal wound whereas frenectomy exposes an area of decaying bone: up to the mucogingival line during the total frenectomy; only on the basis of the frenum in the partial frenectomy.
Submucosal parapical anesthesia is administered by a slow, traceable injection, at a distance from the periosteum, to avoid painful and traumatic distension of vestibular tissues. A palatal withdrawal may be considered if the frenum attachment is palatal.
The frenum is highlighted by a strong attachment to the lip (Fig. 7a) and immobilized by self-locking grips.
The incisions in the attached gingiva are beveled, 1 mm on either side of the frenum attachment on the gingiva, and delineate both sides of a triangle whose gingival apex may eventually be in the interdental space or on the palatal surface (Fig. 7b). If incisions extend into the interdental space, the marginal periodontium of each central incisor should be respected. Then a second triangle at the opposite apex is dissected on the inner surface of the lip, in the labial mucosa, using a blade or gingiva scissors. The common base of the two triangles is the mucogingival line of the adjacent teeth.
All of the tissue within the diamond is resected. The frenum attachment is released in total thickness if the objective is a frenectomy, or in partial thickness if the objective is a frenotomy. The result is a diamond-shaped wound (Fig. 7c).
In the presence of a palate-attached frenum, it is advisable to remove the fibers located in the intermaxillary suture using a periodontal curette. Respect for the interdental papilla is strongly recommended especially in adults 3 .
The edges of the diamond are joined together by a series of discontinuous stitches or a single overstitch from the lip to the gingiva (Fig. 7d) using resorbable polyfilament (or nonabsorbable monofilamentous) suture thread 5/0 or 6/0 in diameter on 1/2 short circular needles (11-13 mm). The triangular excision area of the frenum in its gingival part is protected by a cross suture or a Surgicel ® type cellulose pad.  The sutures can be removed, starting on the 7th postoperative day in children and adolescents, who heal very quickly (Fig. 7th), whereas on the 10th day in adults.
The postoperative results of this cold blade technique are very rarely painful according to our clinical experience. However, we can find in the scientific literature a case for using CO 2 laser to replace the blade and with the goal of decreasing postoperative pain 2 .
If the frenum is oversized and has a papillary attachment, and the area left bare very wide, or if the site is involved in the esthetics of the smile, a triangular gingival graft transplant from an adjacent vestibular interdental donor site may be added 5 . The advantage is that it prevents second-line healing, which can result in a different color and/or texture of the gingiva. A laterally positioned flap 24 can also play this protective role. Bagga (2006) 3      incisors. Frequently, a frenectomy can be performed alone to precede a buried mucosal graft transplant or at the same time as an epithelial-mucosal graft transplant, which has the advantage of simultaneously strengthening the mucogingival complex and deepening the vestibule ( Fig. 8a and b) The maxillary and mandibular lateral frena are most often repositioned by frenotomy because they are smaller than the median frenum, but the indications for frenectomy remain the same.
Results are good if two fundamental principles are respected: partial or complete dissection of the frenum attachment; immobilization of the labial or lingual alveolar mucosa at a distance from the attached gingiva or healing site by second intention.

Elimination of traction on the free gingiva
The frenectomy is effective in restoring anatomical conditions conducive to the long-term maintenance of periodontal health (Fig. 7f and Fig. 9a and b).

Restoration of esthetic gingival contour
For the esthetics of the gingival smile, it is an effective cosmetic procedure if care is taken not to allow the development of unsightly scars from the surgical technique to develop. Sometimes frenectomy healing without tissue input can leave a thin scar that fades over time, while combining the frenectomy with a triangular gingival graft taken from the vestibule, the esthetic result is optimal.

Figure 8b
Situation 2 months after frenectomy and free gingiva graft. The mucogingival complex was reinforced at the 32/42 level and at the ridge level and the vestibule was deepened.

Optimal Healing of Periodontal Surgery
Frenectomy is an essential prerequisite for performing surgical techniques that move tissues and/or require perfect immobilization during healing (in all periodontal regeneration techniques). The frenectomy assists the technical achievement and immediate postoperative tissue stability (Fig. 5b).
Stable closure of the diastema ( Fig. 10a and b) Edwards (1977) 13 showed that in the presence of abnormal frenum associated with diastema, there is a strong tendency for recurrence after orthodontic closure.
For naves (1967) 28 , frenectomy has, in some cases, a therapeutic role on the diastema. In fact, diastemas were completely decreased after a few weeks by this single intervention. But what about the participation of growth and eruption, even for only a few weeks, if these are very active periods?
In any case, to avoid diastema recurrence, it would appear to be more important to have a gingival band attached along the median line and that the central incisors be all at once (crown and root) 24 .    The frenectomy is a simple and routine procedure in periodontal plastic surgery, which should be performed at the right time, according to the indications. In some more complex cases, a free or pedicle epithelial-mucosal graft transplant may be required along with frenectomy.