A new sinus lift technique in conjunction with placement of 265 implants: a 6-year retrospective study

A new surgical crestal approach for implant placement in deficient alveolar ridges is presented. Drills of different and increasing lengths allow the surgeon to approach the membrane without risk of tearing it. The study is supported by 265 cases and a 6-year follow-up period (1994-1999). Implants that were 13 and 15 mm in length were inserted, respectively, in 205 and 60 cases. The alveolar ridge height varied between 4 and 10 mm. All implants were HA-coated and had a 3.25-mm diameter. The results of this investigation suggest that this is a reliable and predictable technique for the prosthetic rehabilitation of the maxillary posterior regions in the presence of anatomical restrictions for implant placement.     

A 5-year retrospective clinical study of the Dentium implants

PURPOSE

The aim of this retrospective study was to evaluate cumulative survival rate (CSR) of Implantium implants followed for 5 years and association between risk factors and the CSR.

MATERIALS AND METHODS

A total of two hundred forty-nine Implantium Implants System (Dentium, Seoul, Korea) placed in ninety-five patients from 2004 to 2009 were investigated with several identified risk factors (sex, systemic disease, smoking, alchohol, reason of tooth loss, length, arch (maxilla or mandible), replace tooth type (incisor, canine, premolar or molar) Kennedy classification, prosthodontic type, prosthodontic design, opposite dentition, abutment type, occlusal material, occlusal unit, splint to tooth, cantilever, other surgery). Clinical examination (mobility, percussion, screw loosening, discomfort, etc.) and radiographic examination data were collected from patient records including all problems during follow-up period according to protocols described earlier. Life table analysis was undertaken to examine the CSR. Cox regression method was conducted to assess the association between potential risk factors and overall CSR.

RESULTS

Five of 249 implants were failed. Four of these were lost before loading. The 5-year implant cumulative survival rate was 97.37%. Cox regression analysis demonstrated a significant predictive association between overall CSR and systemic disease, smoking, reason of tooth loss, arch, Kennedy classification and prosthodontic design (P<.05). The screw related complication was rare. Two abutment screw fractures were found. Another complications of prosthetic components were porcelain fracture, resin facing fracture and denture fracture (n=19).

CONCLUSION

The 5-year CSR of Implantium implants was 97.37%. Implant survival may be dependent upon systemic disease, smoking reason of tooth loss, arch, Kennedy classification and prosthodontic design (P<.05). The presence of systemic diseases and combination of other surgical procedures may be associated with increased implant failure.     

Osteotome sinus floor elevation and simultaneous placement of implants--a 1-year retrospective study with Astra Tech implants

Background: The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall, although less invasive techniques with osteotomes have been used since 1994. Purpose: The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting. Materials and Methods: The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less. Results: The mean height of the alveolar process in the intended implant sites was 6.3 ± 0.3 mm, and the mean elevation of the sinus floor was 4.4 ± 0.2 mm. At the 1‐year follow‐up, two implants had been lost, both in edentulous patients. The remaining 51 implants inserted were in function, giving a 1‐year cumulative survival rate of 96%. Implants used in single‐tooth replacements and in partially edentulous cases had a 100% survival rate. The mean marginal bone level at the time of loading of the implants was 0.1 ± 0.04 mm below the reference point. One year later, the corresponding value was 0.5 ± 0.06 mm. The mean bone loss between the two examinations was 0.4 ± 0.05 mm. Conclusions: The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla.     

A 10-year multicenter retrospective clinical study of 1715 implants placed with the edentulous ridge expansion technique

This work evaluates the data gathered over a period of 10 years on implants placed with the edentulous ridge expansion (ERE) technique by a group of specially trained and experienced surgeons. Between January 1992 and December 2001, 1715 consecutive implants were placed with the ERE technique by nine different dental surgeons using a common surgical protocol. The implants were followed up using a common protocol and a specific database for the collection of clinical information on the patient, surgery, and follow-up, including the 1986 Albrektsson et al criteria for implant success. All data gathered at the end of the study period were placed in a common database. The overall success rate over the O-year follow-up period was 95.7%.     

1144颗种植牙修复临床效果分析

目的评价北京口腔医院种植中心2000年1月至2005年4月所完成种植修复病例的临床效果。方法2000年1月至2005年4月共植人种植体2158颗,随访观察时间3-8年。依照珠海种植会议标准,采用寿命表法进行统计分析。结果2000年1月至2005年4月种植病例1125人,随访到577人,1144颗种植体。累计5年存留率91．37％。结论累计种植5年存留率达到91．37％。     

Zygomatic implants using the sinus slot technique: clinical report of a patient series

PURPOSE: The management of 5 patients with extreme maxillary atrophy and treatment consisting of maxillary fixed prostheses supported by conventional implants and zygomatic fixations positioned according to the sinus slot technique is reported. MATERIALS AND METHODS: A total of 16 conventional implants were placed, together with 2 pterygoid implants and 10 zygomatic fixations. In 2 cases zygomatic fixation could not be performed on the alveolar ridge, thus requiring palatal displacement. One patient presented nasogenian ecchymosis. The fixed rehabilitations were either screwed or cemented after 5 to 6 months. RESULTS: Follow-up from implantation lasted 12 to 18 months, during which the prostheses and implants remained stable and in function. DISCUSSION: The placement of zygomatic fixations based on the sinus slot technique offers advantages over the conventional technique, though extreme atrophy of the alveolar processes does not allow fixation at the supracrestal level, and complications may develop. CONCLUSION: While zygomatic fixation is a valid alternative for treating the atrophic jaw, long-term studies are required to confirm its efficacy.     

Dental implants in alveolar cleft patients: a retrospective study

Since 1994, 15 cleft patients have received dental implants after treatment of the alveolar clefts by osteoplastic measures. Altogether 23 dental implants were undertaken. Twelve implants were inserted after tertiary osteoplasty, 7 with simultaneous repeat-osteoplasty, and another 4 implants following two-stage re-osteoplasty. In 11 patients with a total of 17 implants clinical and radiological follow-ups were performed. An individual crown was constructed on each of the implants. The radiological evaluation revealed that 70% of the implants were fully embedded in bone. All implants except one remained in situ and stable. Thus, the success rate was 96% retention. It is believed that a dental implant in the alveolar cleft may be lost because of its unfavourable location in terms of stability and function or because it was inserted too late. Scars resulting from previous surgery can also play a role in the failure of an implant. Therefore it is proposed that dental implants should not be inserted later than 6 to 8 weeks following osteoplasty of the cleft alveolus.     

Less invasive sinus lift using the technique of Summers modified by Lazzara

The sinus floor elevation (sinus lift) is a procedure used for treating patients with very large pneumatisation of the maxillary sinus and thereby with severe atrophic maxilla (height of the residual alveolar bone between 5 and 8 mm). A modification of this technique is the osteotome sinus floor elevation: this is a less invasive method of creating sites with osteotomes by crestal approach in locations with insufficient bone for insertion of oral implants. With larger osteotomes, bone graft substitutes are placed through the osteotomy site to provide a sinus floor elevation and an augmentation of the crestal bone. Therefore, via the osteotome technique, longer oral implants can be inserted.     

Residual ridge resorption in the edentulous maxilla in patients with implant-supported mandibular overdentures: an 8-year retrospective study

PURPOSE: This retrospective study radiologically investigated alveolar bone resorption in the edentulous maxilla in patients with implant-supported mandibular overdentures. MATERIALS AND METHODS: This study consisted of 35 healthy, completely edentulous patients with a mean age of 59.7 years. They had received two implants between the mental foramina. New bar-retained mandibular overdentures and maxillary complete dentures were fabricated. Standardized panoramic radiographs taken subsequent to loading and at annual recall visits for up to 8 years were measured for alveolar bone loss in the maxilla. Bone areas and areas of reference not subject to resorption were measured with a planimetry program. The proportional value between both was expressed as a ratio (R). Bone loss was expressed as a change in R between two time points. Differences in the resorption rate between the anterior and posterior parts of the maxilla were investigated. RESULTS: Residual ridge resorption continued during the follow-up period and revealed high individual variability. With a range of 5% to 11% (median) loss in the original bone height, it was significantly (P < .031) more pronounced in the anterior than posterior maxilla (2% to 7%) from the second through eighth years. Regression analysis of the medians revealed a relatively high correlation between time and bone loss in both anterior and posterior parts of the maxilla. CONCLUSION: The anterior anchorage of mandibular overdentures by means of two implants and an ovoid bar was associated with slightly higher resorption in the anterior than in the posterior part of the edentulous maxilla.