Placement In Atrophic Maxilla Research Articles

Primary stability of different implant macrodesigns in a sinus floor elevation simulated model: an ex vivo study

BackgroundA novel type of implant (Straumann® BLX implant) has been developed for certain stability from the mechanical and biological aspects and is expected for the implant placement in atrophic maxilla with sinus floor elevation (SFE).PurposeThe aim of this study was to evaluate the primary stability in the implants with different macrodesigns in an SFE simulated model. Primary stabilities defined as maximum insertion torque (MIT) and implant stability quotient (ISQ) were compared between this novel type of implant and other types.Materials and MethodsFive types of Straumann® 10 mm length implants (Standard Plus; SP, Tapered Effect; TE, Bone Level; BL, Bone Level Tapered; BLT and BLX) and two types of Straumann® 6 mm length implants (SP short, BLX short) were used in this study. Each implant was inserted through 5 mm–thick porcine iliac crest blocks (an SFE simulated model). Primary stability was evaluated by using MIT and ISQ.ResultsThe mean value of MIT for BLX group showed significantly higher values than SP, BL (p < 0.01), and TE (p < 0.05) groups. The mean value of ISQ for BLX group was significantly higher than the other groups (p < 0.01). The mean value of MIT and ISQ for BLX and BLX short group were significantly higher than those for SP and SP short group (p < 0.01).ConclusionsIn an SFE simulated ex vivo model, BLX group showed the highest values. These results suggest that implant selection can play a crucial role in the achievement of primary stability during SFE and simultaneous implant placement.

The comparative evaluation of transcrestal and lateral sinus floor elevation in sites with residual bone height ≤6 mm: A two-year prospective randomized study.

To compare clinical and radiographic outcomes between transcrestal sinus floor elevation (TSFE) and lateral sinus floor elevation (LSFE) approaches of simultaneous implant placement in atrophic maxilla. Patients with a residual bone height (RBH) ≤6mm were enrolled and randomly assigned to TSFE and LSFE groups. Patients in both groups simultaneously underwent sinus floor elevation with bovine-derived xenograft and implant placement. Clinical and radiographic results were evaluated immediately after surgery and after 6, 12, 18, and 24months. The endo-sinus bone gain (ESBG), apical implant bone height (ABH), endo-sinus bone-implant contact rate (EBICR), and crestal bone level (CBL) were assessed using panoramic radiographs. Forty-one implants (TSFE: 21, LSFE: 20) were placed in cases with a mean RBH of 3.77±1.16mm. All implants obtained clinical success and satisfactory ESBG at 24months. No significant differences were found in ESBG and ABH between two groups immediately after surgery, but LSFE group showed significantly higher values than TSFE group thereafter. Grafts in TSFE group reached stability 6months earlier than that in LSFE group. In both groups, EBICR was almost 100%, and CBL showed no detectable changes. LSFE can achieve higher ESBG 2years after surgery. Otherwise, TSFE could be an alternative to LSFE, when the access for lateral window preparation is limited. Both approaches were highly predictable for RBH≤6mm during 24-month observation period for the implants placed simultaneously.

Alveolar ridge split technique and immediate implant placement in atrophic maxilla. Case series

Background: Alveolar ridge split technique (ARST) is a surgical procedure performed for horizontal ridge augmentation in cases of narrow crestal ridges. It is a biologically oriented technique, taking advantage of the osteogenic and osteoconductive dynamic of the native bone. Recently, the utilization of devices such as thin diamond disks or piezoelectric cutting devices has enhanced ARST success rate, reduced surgical time and patient's morbidity, regardless of bone quality. Aim/Hypothesis: The purpose of this poster is to present and discuss our experience in a series of clinical cases where ARST was performed for horizontal bone augmentation with simultaneous implant placement, using classical or piezoelectric-assisted surgical procedures. Materials and Methods: ARST was performed in 6 patients with 10 sites of horizontal defects. Under local anesthesia, a crestal incision was performed and a full thickness mucoperiosteal flap was reflected. Initial osteotomy was done using the classical technique in 6 cases (diamond disk, rotary burs), while a piezoelectric device was used to the remaining 4 cases. Osteotomes and chisels with gradually increasing dimensions were used to expand the alveolar ridge to facilitate the immediate placement of 18 implants, approximately 2 mm subcrestally in order to prevent marginal bone loss. The remaining space between bony plates was filled with allograft or xenograft and covered with collagen membrane in 9 cases, while in one case no bone graft or membrane were used. Primary closure without tension was achieved with periosteum releasing incisions of the buccal flap. Post-operative instructions included administration of antibiotic and analgesic, chlorhexidine solution, smoke cessation and thorough oral hygiene. Results: Sutures were removed 10 days postoperatively. Follow up was uneventful for 5 out of 6 patients. One patient did not comply with the postoperative instructions, applying poor oral hygiene and continuing smoking as before which resulted in exposure of the collagen-membrane the second week, leading to secondary wound closure compromising the augmentation. A new CBCT was performed 4 months following the split which revealed successful bone augmentation and implant osseointegration without any significant bone loss around the implants. Oral rehabilitation with either fixed or removable prosthetics was accomplished and the patients remain under systematic review. Conclusions and Clinical Implications: ARST is a predictable and reliable procedure characterized by its low invasiveness and morbidity. The major advantage is the simultaneous bone augmentation- implant placement, which provides reduced treatment time and cost. Piezoelectric devices make the split technique easier and safer, decreasing the risk of complications in the treatment of extremely atrophic crests. ARST's success and efficacy depends greatly on patient selection in order for the basic anatomical criteria to be fulfilled. Keywords: ridge splitting, horizontal bone augmentation, piezoelectric device

PC337: Enucleation and bone augmentation of the incisive canal prior to implant placement in atrophic maxilla

PC337: Enucleation and bone augmentation of the incisive canal prior to implant placement in atrophic maxilla

Guided Bone Regeneration with Bone Expansion for Implant Placement in Atrophic Maxilla: A Case Report

Lack of sufficient bone to place an implant at the most functionally and esthetically appropriate position is a common problem, especially in the maxillary anterior esthetic zone region. A surgical bone spreading technique is proposed to augment the alveolar ridge for horizontal defects through a localized alveolar osteotomy and interpositional bone graft. Bone spreading technique (BST) is horizontal augmentation with minimal trauma for simultaneous implant placement. The foremost advantage of this method is that the buccal wall expands after the medullar bone is compressed against the cortical bone. The lateral dilation and compaction of the medullar bone enhances primary stability.