Effect of different implant placement depths on crestal bone levels and soft tissue behavior: a randomized clinical trial

• Published in: Clinical oral implants research Vol. 28; no. 10; pp. 1227 - 1233
• Main Authors: Siqueira, Rafael Amorim Cavalcanti, Fontão, Flávia Noemy Gasparini Kiatake, Sartori, Ivete Aparecida de Mattias, Santos, Paulo Gustavo Freitas, Bernardes, Sérgio Rocha, Tiossi, Rodrigo
• Format: Journal Article
• Language: English
• Published: Denmark Wiley Subscription Services, Inc 01-10-2017
• Subjects: Aged; Alveolar Process - anatomy & histology; Bone implants; Bone loss; bone remodeling; Bone-Implant Interface - physiology; Clinical trials; cone‐beam computed tomography; Dental Implantation, Endosseous - methods; Dental implants; Dentistry; Gingiva - physiology; Humans; immediate dental implant loading; Mandible; Middle Aged; Mucosa; Patients; Radiographs; Radiography; Recession; Variance analysis; cone-beam computed tomography; immediate dental implant loading; bone remodeling
• ISSN: 0905-7161; 1600-0501
• DOI: 10.1111/clr.12946

Objectives
This randomized clinical trial analyzed crestal bone changes and soft tissue dimensions surrounding implants with an internal tapered connection placed in the mandible anterior region at different depths (equicrestal and subcrestal).
Materials and methods
Eleven edentulous patients (five implants per patient) were randomly divided in a split‐mouth design: G1, 28 equicrestal implants; and G2, 27 subcrestal implants. All implants were immediately loaded. Correlation between keratinized tissue width (KTW) and vertical mucosa thickness (MT) with soft tissue recession was analyzed. Intraoral radiographs were used to evaluate crestal bone changes. Patients were assessed immediately, 4‐, and 8‐months after implant placement. Rank‐based ANOVA‐type statistical test was used for comparison between groups (α = 0.05).
Results
Fifty‐five implants (G1 = 28 and G2 = 27) were assessed in 11 patients. Implant survival rate was 100% for both groups. Both tested implant placement depths presented similar crestal bone loss (P > 0.05). Significant crestal bone loss for each group was found in the different measurement times (T4 and T8) (P < 0.05). Implant placement depths, KTW, and vertical MT had no effect on soft tissue recession (P > 0.05).
Conclusions
Different implant placement depths do not influence crestal bone changes. Soft tissue behavior is not influenced by different implant placement depths or by the amount of keratinized tissue.