New possibilities – avoiding bone grafting with short implants

Implant placement in the posterior regions can be limited due to anatomical conditions. One of the most problematic areas is the posterior maxilla, presenting in most cases with a limited bone height due to the pneumatisation of the maxillary sinus, and poor bone quality. Another complicating factor in posterior regions is the general exposure to greater masticatory loads than in anterior regions. Recent clinical studies on short implants with rough surfaces have reported survival rates similar to implants in general. Those studies were on implants of 7mm or less in length. These authors only took into consideration articles reporting on implants of 6mm or less in length – some of them reported similar success rates using 5mm short implants, in comparison to longer implants placed in augmented bone. The authors are currently preparing a clinical study protocol to place implants on patients with only 3-4mm available bone under the sinus, without any bone grafting. A bone height of 3-4mm may be enough to place implants without sinus bone graft. Short implants The use of short implants with deep threads is a predictable treatment method for an implant restoration, even in difficult anatomical situations, to avoid complicated augmentation procedures. In the case reports presented here, short implants with deep threads showed good clinical results while being engaged only 3-4mm with the residual bone. It has been suggested that this is a result of the special thread design (Figure 1), which can increase the bone-implant contact (BIC) and primary stability dramatically, having a large surface area in contact with bone, even in very low alveolar ridges (3-4mm in height). This article presents two case studies using a new implant with a novel macrostructure and thread design, which have proved to give excellent results in compromised bone situations. A three-dimensional bond between bone and implant is achieved; bone in-growth between the threads (Figure 2) increases the implant resistance to occlusal and shear forces. Clinicians often face challenges when placing dental implants in areas of insufficient bone height. This problem is encountered mostly in the posterior mandible, because of the mandibular nerve canal, and in the posterior maxilla, due to the pneumatisation of the maxillary sinuses and poor bone quality. The conventional treatments for these cases are various bone grafting procedures (sinus lift, vertical bone augmentation, GBR). These procedures have good predictable results, but they are related to high complication rates and cost, increased post-operative morbidity and stress to the patients, as well as a longer treatment period. These procedures should only be carried out by an experienced surgeon – which is an essential factor for successful treatment. Short implants (of 6mm or less) were introduced as a potential alternative to bone augmentation procedures in cases of Soheil Bechara, Kwang Bum Park, Ričardas Kubilius and Algirdas Lukošiūnas present case studies where implants were placed in 3-4mm of residual bone under the sinus without bone grafting CLINICAL