The thickness of labial bone affects the esthetics of immediate implant placement and provisionalization in the esthetic zone: A prospective cohort study.

BACKGROUND: A 1-2 mm thick labial plate is generally advocated in immediate implant placement and provisionalization (IIPP). However, most of the human labial plates fail to meet this requirement. PURPOSE: This study aimed to investigate the effect of labial plate thickness on hard tissue, soft tissue, and esthetic outcomes in IIPP. MATERIALS AND METHODS: In this prospective cohort study, 40 patients received IIPP of 50 single-crown implants in the anterior maxilla. Patients were categorized into three groups according to their presurgical thickness of labial bone: 0-0.5, 0.5-1, and >/= 1 mm. CBCT, mucosa recession and the papilla index were used to analyze labial hard and soft tissue alterations with a 1-year follow-up. RESULTS: At 1 year, OCI bone losses were 1.17 +/- 0.73, 0.37 +/- 0.39, 0.46 +/- 0.35 mm; ICH bone losses were 2.23 +/- 1.83, 0.74 +/- 0.71, 0.72 +/- 1.27 mm; TM recessions were 1.00 +/- 0.51, -0.06 +/- 0.37, -0.30 +/- 0.88 mm; TL recessions were 0.61 +/- 1.02, -0.18 +/- 0.40, -0.26 +/- 1.15 mm; TD recessions were 0.61 +/- 1.02, -0.18 +/- 0.40, -0.26 +/- 1.15 mm; PIS scores were 1.63 +/- 0.64, 2.20 +/- 0.71, 2.71 +/- 0.57 in group 0-0.5, 0.5-1 and >/= 1 mm, respectively. No statistical significance was found between group 0.5-1 and >/= 1 mm in bone resorption, gingival recession, and papilla index. The bone resorption and gingival recession were significantly the highest in group 0-0.5 mm at 6 months and 1 year. CONCLUSIONS: Group 0.5-1 mm had similar tissue dimensional alteration as group >/=1 mm, while group <0.5 mm suffered more massive bone resorption and gingival recession. Concerning the thickness of the labial plate, this study may suggest an expansion in the indication of IIPP.