Interventions for replacing missing teeth: management of soft tissues for dental implants.

BACKGROUND: Dental implants are usually placed by elevating a soft tissue flap, but in some instances, they can also be placed flapless reducing patient discomfort. Several flap and suturing techniques have been proposed. Soft tissues are often manipulated and augmented for aesthetic reasons. It is often recommended that implants are surrounded by a sufficient width of attached/keratinized mucosa to improve their long-term prognosis.

OBJECTIVES: To evaluate whether (1a) flapless procedures are beneficial for patients, and (1b) which is the ideal flap design; whether (2a) soft tissue correction/augmentation techniques are beneficial for patients, and (2b) which are the best techniques; whether (3a) techniques to increase the perimplant keratinized mucosa are beneficial for patients, and (3b) which are the best techniques; and (4) which are the best suturing techniques/materials.

SEARCH STRATEGY: The Cochrane Oral Health Group's Trials Register, The Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were searched. Handsearching included several dental journals. Authors of all identified trials, an internet discussion group and 55 dental implant manufacturers were contacted to find unpublished randomised controlled trials (RCTs). The last electronic search was conducted on 15 January 2007.

SELECTION CRITERIA: All RCTs of root-form osseointegrated dental implants comparing various techniques to handle soft tissues in relation to dental implants. Outcome measures were: prosthetic and implant failures, aesthetics evaluated by patients and dentists, biological complications, postoperative pain, patient preference, ease of maintenance by patient, and width of the attached/keratinized mucosa.

DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two review authors. Authors were contacted for missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals (CI). Heterogeneity was to be investigated including both clinical and methodological factors.

MAIN RESULTS: Eight potentially eligible RCTs were identified and five trials including 140 patients in total were included. Two trials (100 patients) compared flapless placement of dental implants with conventional flap elevation, two trials (20 patients) crestal versus vestibular incisions, and one trial (20 patients) Erbium:YAG laser versus flap elevation at the second-stage surgery for implant exposure. On a patient, rather than per implant basis, implants placed with a flapless technique and implant exposures performed with laser induced statistically significant less postoperative pain than flap elevation. There were no other statistically significant differences for any of the remaining analyses.

AUTHORS' CONCLUSIONS: Flapless implant placement is feasible and has been shown to reduce patient postoperative discomfort in adequately selected patients. There is insufficient reliable evidence to provide recommendations on which are the best incision/suture techniques/materials, or whether techniques to correct/augment perimplant soft tissues or to increase the width of keratinized/attached mucosa are beneficial to patients or not. Properly designed and conducted RCTs are needed to provide reliable answers to these questions.