Gummy smile is one of the major esthetic problems nowadays; it is due to several causes that either dental or skeletal. Etiology of the gummy smile is altered passive eruption, vertical maxillary excess, different gingival enlargement conditions, deficient maxillary lip length and excessive maxillary lip mobility, dento alveolar extrusion, combination of all these factors.

Altered passive eruption is considered to be one of the most major causes, it is classified into two types according to the location of the mucogingival junction with respect to the bone crest and each type has two subtypes . Esthetic crown lengthening is the treatment of choice for subtype B in both types as bone removal is mandatory to create a space for the biological width.

Most of the studies stated that there is some degree of relapse of the gingival tissues after the procedures in the follow ups, that relapse was related to the biotype of the gingival tissues, the flap placement close or far from the bone can be correlated to the suturing technique used for closure of the tissues.

In the investigator's study comparing of two different suturing technique was done to evaluated their effect on gingival tissue relapse, 30 patients (26 females and 4 males) were divided between 2 groups each group consisted of 15 patients. In the first group periosteal suturing technique was done in the second figure of eight (modified interrupted) suturing technique was.

Evaluation of the tissue relapse was done through the assessment of the amount of the attached gingival tissues level of gingival margin and marginal tissue contour before and after the surgery.

The results of the study showed that tissue relapse was more in the periosteal suturing technique group that was related to the pressure on the tissues due to the fixation of the suture at the periostium, the papillary tissue also showed more inflammation in the follow up period prior to suture removal. The figure of eight group showed less relapse and tissue inflammation as it prevents flap edge overlap and is tension free therefore better blood supply to the tissue.

Patients were generally satisfied post-surgical with their smile, gingival tissue visibility and teeth dimensions inspite of the relapse but it was better than prior to surgery. Also they would recommend it to other patients complaining from the same problem.

Thirty patients (26 females, 4 males), who were candidates for esthetic crown lengthening, participated in this prospective clinical trial.

Group I (15 patients) (vertical mattress suturing technique) :

Esthetic crown lengthening procedure: internal bevel, sulcular and interdental incisions, flap elevation, bone removal then External vertical mattress suture was done (periosteal suture).

Group II (15 patients) (Figure of eight suturing technique) :

Esthetic crown lengthening procedure: internal bevel, sulcular and interdental incisions, flap elevation, bone removal then modified interrupted suture was done (Figure of eight suture).

Inclusion Criteria:

• Patients complaining from gummy smile (altered passive eruption)
• Bone level is 2 mm or less from the cemento enamel junction
• Teeth included were free from any periodontal destruction
• Good compliance with the plaque control instructions following initial therapy.
• Availability for follow up and maintenance program

Exclusion Criteria:

• Presence of systemic diseases which could influence the outcome of the therapy (American society of anesthesiologists I, ASA I).
• Patient suffering from periodontitis stage 4 grade c.
• Presence of smoking habit.
• Presence of occlusion interference.
• Pregnant females and lactating females. .
• Vulnerable groups of patients (handicapped, mentally retarded, prisoners).
• Restored teeth.

when the study is done the results will be published with the protocol

the data will be available starting next month and for 1 year

the keywords esthetic crown lengthening, suturing techniques in dentistry

The study consisted of two groups the number of patient was determined by sample size calculation through G power analysis (15 patients). Patients were randomly selected using computer generated randomization (www.randomizer.org).