Esthetic outcome and alterations of soft tissue around single implant crowns: a 2-year prospective study.

OBJECTIVE: The aim of this prospective study was to assess the esthetic outcome and alterations of peri-implant soft tissue using tissue-level implants. Furthermore, the influencing factors, including grafting and gingival biotype, of esthetic outcome of peri-implant soft tissue were also evaluated. MATERIALS AND METHODS: Of 38 patients with single missing anterior tooth in maxilla were treated with a Straumann (®) Standard Plus SLA implant. Bone augmentation was performed in 24 patients. Follow-up was conducted at 12 and 24 months after definitive crowns placement. Esthetic outcome using the pink esthetic score/white esthetic score (PES/WES) and clinical parameters were evaluated. RESULTS: The mean PES/WES value at baseline, 1-year, and 2-year examination was 13.79, 14.87, and 14.96. Significant improvement was found between baseline and 1-year examination (P < 0.01). And the improvement between 1-year and 2-year examination was not significant (P = 0.40). The mean PES changing value in patients with thick biotype was significantly higher than those with thin biotype at 2-year after definitive crowns placement (P = 0.03). Graft procedure had an unfavorable effect on mean PES value both at baseline and at follow-up (P < 0.01). No implants were lost at 2-year examination. Three patients experienced peri-implant infection. No significant difference was found with the passage of time in modified plaque index (mPI), probing pocket depth (PPD), and modified bleeding index (mBI). CONCLUSION: According to the present prospective clinical study, it can be concluded that it is feasible to use tissue-level implant to support single crowns in esthetic area. Favorable short-term esthetic outcome and stability of soft tissue around single implant crowns can be expected in patients with or without graft. However, graft procedures might have an unfavorable effect on the esthetic outcome. Gingival biotype can be considered as prognostic factor for esthetic outcome. RCTs with long-term follow-up are needed to provide evidence for the long-term stability of peri-implant soft tissue using tissue-level implant systems.

[Osteotome sinus floor elevation without bone grafting: a 2-year prospective clinical study].

PURPOSE: The aim of this study was to evaluate the osteotome sinus floor elevation procedure with Straumann implants without bone grafting through observing the implant survival rate and the change of bone around the implant, and explored new bone formation and stability when the implants protruding in the sinus less than 3mm. METHODS: 23 patients with single upper maxillary molar lost were included in this study. The mean residual bone height (RBH) under the maxillary sinus was 5-8 mm and the distance of the implants protruding into the sinus was less than 3mm without bone grafting. A healing period of 3-4 months was allowed before abutment tightening at 35 N x cm. All the patients were followed up for 2 years to evaluate the implant survival rate. X-ray measurements (immediately after implant placement, after 3,6,12,24 months postoperatively) were performed to calculate the length of the implant protruding into the sinus and if the new bone formed near it. RESULTS: At the end of 2-year, the implant survival rate was 100% and the implants resisted the applied 35 N.cm torque and supported the definitive prosthesis well. The mesial and the distal sides of the implants protruding into the sinus had new bone formation. No hard tissue could be seen around the apical implant 3 months after inserting and the boundary between the new bone and the original sinus floor could not be seen 2 years after surgery. CONCLUSION: Elevation of the sinus membrane alone without addition of bone grafting could have the similar effect to the OSFE with bone grafting.

[Comparison of acellular dermal matrix graft and palatal connective tissue graft in the augmentation of labial tissue around implants].

PURPOSE: To compare the effect of palatal connective tissue graft and acellular dermal matrix (ADM) transplantation to improve the labial contour of implants. METHODS: 22 patients with single missing tooth and buccal soft tissue defects in the anterior maxilla underwent dental implant therapy. Simultaneously, 12 patients received palatal connective tissue transplantation, while 10 patients received ADM graft and all sites were studied for 12 months. The horizontal width of the alveolar crest were evaluated before surgery and 2 weeks, 3, 6, 12 months after surgery through cast study,statistical evaluation was completed with Student's t test using SAS6.12 software package to determine whether significant differences existed at the 95% significance level. RESULTS: The survival rate for both groups during the 12- month follow-up was 100%. The horizontal widths of alveolar crest of both groups at the follow-up 2 weeks and 3, 6, 12 months were significantly higher than the preoperative values (P<0.05). There was no significant difference between the groups in horizontal width increase of alveolar crest at all time points postoperatively. CONCLUSIONS: Palatal submucosal connective tissue graft and acellular dermal matrix subperiosteal transplantation can equally correct the buccal soft tissue defects around the dental implants.

[Buccal soft tissue augmentation using acellular dermal matrix in implant therapy].

OBJECTIVE: To evaluate the use of acellular dermal matrix (ADM) to improve esthetic effects of alveolar ridge in dental implantology. METHODS: Fifty patients with similar single missing tooth in the anterior maxilla were randomly divided into two groups: the ADM group was treated with dental implant therapy plus ADM transplantation; the control group was treated with dental implant therapy alone. The periodontal parameters and the changes of horizontal width of alveolar crest at implant zones were evaluated before surgery and 12 weeks after surgery. RESULTS: All operated sites healed uneventfully. Mean horizontal width of alveolar crest in ADM group increased by (3.10 +/- 0.64) mm at 12 weeks and the control group increased by (0.30 +/- 0.50) mm, The volume increase showed a significant difference groups (P < 0.05). Mean horizontal width of alveolar crest in ADM group was (11.50 +/- 1.48) mm and the contralateral alveolar crest was (11.60 +/- 1.60) mm (P > 0.05). CONCLUSIONS: ADM is a suitable material for the treatment of soft tissue deformities due to its biocompatibility and horizontal gain of soft tissue.