Tiziano Testori

Immediate occlusal loading and tilted implants for the rehabilitation of the atrophic edentulous maxilla: 1-year interim results of a multicenter prospective study

OBJECTIVES The aims of this prospective study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants for the rehabilitation of fully edentulous maxillae and to compare the outcome of axial vs. tilted implants. MATERIAL AND METHODS Forty-one patients with edentulous maxillae were included in the study. Each patient received a full-arch fixed bridge supported by four axial implants and two distal tilted implants. Loading was applied within 48 h from surgery. Patients were scheduled for follow-up at 6 months, 1 year and annually up to 5 years. Radiographic evaluation of marginal bone-level change was performed at 1 year. RESULTS One patient died 4 months after surgery. Thirty patients were followed for a minimum of 1 year (range 3-42 months, mean 22.1 months). Three failures were recorded at 1-year follow-up (two axial implants and one tilted). Two more implants (one tilted and one axially placed) were lost within 18 months of loading. The 1-year implant survival rate was 98.8% for both axial and tilted implants. Prosthesis success rate was 100% at 1 year. Marginal bone loss around axial and tilted implants at 12-month evaluation was similar, being, respectively, 0.9+/-0.4 (standard deviation) mm and 0.8+/-0.5 mm. CONCLUSIONS The present preliminary data suggest that immediate loading associated with tilted implants could be considered to be a viable treatment modality for the atrophic maxilla and that there does not seem to be a different clinical outcome between tilted and axial implants.

Success and failure in periradicular surgeryA longitudinal retrospective analysis

The objective of the present study was to compare the success rates of 2 different periapical surgical techniques, the traditional technique with rotary instruments and the ultrasonic technique, which uses ultrasonic retrotips. A longitudinal retrospective study was carried out on 302 apices (181 teeth) that had undergone periapical surgery. Surgical outcome was evaluated by 2 independent operators using standardized periapical radiographs. Each radiographic finding was classified into 1 of 4 groups: complete healing, incomplete healing, uncertain healing, and unsatisfactory outcome (failure). An SAS statistical analysis system was used for data management and analysis. Prognostic factors were determined by means of the Fisher exact test. Complete healing after 4.6 years (the average follow-up period) was observed in 68% of the teeth treated through the use of the standard technique and 85% of those treated through the use of the ultrasonic technique. The success rate increased as the follow-up period lengthened (68.4% at 2 years vs 80% at 6 years). The success rate was higher in maxillary (77.9%) than in mandibular (66.1%) teeth. A comparison between the retrofilling materials was not feasible because all teeth in the standard technique group were retrofilled with amalgam and all teeth in the ultrasonic group were retrofilled with Super-EBA.

Immediate Rehabilitation of the Mandible with Fixed Full Prosthesis Supported by Axial and Tilted Implants: Interim Results of a Single Cohort Prospective Study

PURPOSE The aims of this prospective study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants for the rehabilitation of the mandible and to compare the outcome of axial versus tilted implants. MATERIALS AND METHODS Sixty-two patients (34 women and 28 men) were included in the study. Each patient received a full-arch fixed bridge supported by two axial implants and two distal tilted implants (All-on-Four, Nobel Biocare AB, Göteborg, Sweden). Loading was applied within 48 hours of surgery. Patients were scheduled for follow-up at 6, 12, 18, and 24 months, and annually up to 5 years. At each follow-up, plaque level and bleeding scores were assessed; moreover, patients satisfaction for aesthetics and function was evaluated by a questionnaire. Radiographic evaluation of marginal bone level change was performed at 1 year. RESULTS The overall follow-up range was 6 to 43 months (mean 22.4 months). Forty-four patients were followed for a minimum of 1 year. No implant failures were recorded to date, leading to a cumulative implant survival and prosthesis success rate of 100%. Plaque level and bleeding scores showed progressive decrease over time, parallel to increase of satisfaction for both aesthetics and function. No significant difference in marginal bone loss was found between tilted and axial implants at 1-year evaluation. CONCLUSION The present preliminary data suggest that immediate loading associated with tilted implants could be considered a viable treatment modality for the mandible.

Performance of short implants in partial restorations: 3-year follow-up of Osseotite implants

Short-length implants should be at a performance disadvantage because of the more limited surface area with which to resist occlusal forces. Nevertheless, anecdotal observations find many short implants performing well in different restorative conditions. This retrospective, multicenter study seeks to compare formally implant performance based on length. The success of 7 and 8.5-mm Osseotite® implants (Implant Innovations, Inc., Palm Beach Gardens, FL) was determined as: absence of mobility; no persistent and/or irreversible signs or symptoms of pain, infection, paresthesia, or violation of the mandibular canal; no evidence of peri-implant radiolucency; and no progressive crestal bone loss. Implant location, restoration type, bone density, andsmoking status of the patients were recorded. A total of 188 patients received 311 short Osseotite® implants that were placed mostly in soft bone and supported 216 partially edentulous cases in the maxilla or mandible. Most restorations (95.2%) are short-span fixed partial dentures placed in the posterior sextants. During 3 years of follow-up, 13 implants failed, yielding a cumulative success rate of 95.8%. In 9 of these cases, failure occurred before prosthetic loading, and in 4, the patient was a smoker. The overall success rate compares favorably with the available literature for the performance of implants in general, and short implants in particular.

Long-term implant survival in the grafted maxillary sinus: a systematic review.

The predictability of maxillary sinus augmentation has been extensively reported. Procedural outcomes, most often measured as implant survival rates, have customarily used inclusion criteria that included a minimum 1-year loading time. The inclusion criteria of this review extended the minimum postloading evaluation to 3 years to determine if the previously reported short-term survival rates are maintained. An electronic search of the literature was performed and retrieved articles were screened using specific inclusion criteria, paramount of which was a minimum of 3 years of follow-up. The search revealed 18 articles for the lateral window approach (6,500 implants in 2,149 patients) and 7 for the transalveolar approach (1,257 implants in 704 patients). Overall, implant survival after a minimum of 3 years loading was 93.7% and 97.2% for the lateral window and transalveolar approaches, respectively. Of importance is the fact that 80% of failures occurred within the first year and 93.1% of the failures occurred within 3 years. The risk of implant failure after 3 years can now be directly calculated as the overall risk of failure after 3 years (6.3%) × the incidence of late failures (6.9%), thus equaling 0.43%. This review discredits the theory that studies of a lower level of evidence report inflated results when compared with prospective randomized controlled clinical trials.

Workshop Guidelines on Immediate Loading in Implant Dentistry

P redictable formation of a direct bone-toimplant interface is a treatment goal in implant dentistry. The 2-stage surgical protocol established by Branemark et al to accomplish osseointegration consisted of several prerequisites, including (1) countersinking the implant below the crestal bone, (2) obtaining and maintaining a soft-tissue covering over the implant for 3 to 6 months, and (3) maintaining a minimally loaded implant environment for 3 to 6 months. The primary reasons cited for the submerged, countersunk, surgical approach to implant placement were (1) to reduce and minimize the risk of bacterial infection, (2) to prevent apical migration of the oral epithelium along the body of the implant, and (3) to minimize the risk of early implant loading during bone remodeling. After this procedure, a second-stage surgery was necessary to uncover these implants and place a prosthetic abutment. Predictable, long-term, clinical rigid fixation has been reported after this protocol in patients who were either completely or partially edentulous. During the past 15 years, several authors have reported that root-form implants may osseointegrate, even though the implants extend above the bone and through the soft tissues during early bone remodeling. This surgical approach has been called a 1-stage or nonsubmerged implant procedure because it eliminates the second-stage implant uncovery surgery. As a result, the discomfort, inconvenience, and appointments of the surgery and suture removal are eliminated. In addition, the soft tissue is more mature before fabricating a final prosthesis.

Immediate non-occlusal vs. early loading of dental implants in partially edentulous patients: a multicentre randomized clinical trial. Peri-implant bone and soft-tissue levels.

OBJECTIVES To compare peri-implant bone and soft-tissue levels of immediately non-occlusally loaded vs. non-submerged early loaded implants in partially edentulous patients up to 14 months after placement. MATERIAL AND METHODS Fifty-two patients were randomized in five Italian private practices: 25 in the immediately loaded group and 27 in the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > or = 30 N cm, and splinted implants with a torque of > or = 20 N cm. Immediately loaded implants were provided with non-occluding temporary restorations within 48 h. After 2 months, the provisional restorations were placed in full occlusion. Implants were early loaded after 2 months. Final restorations were provided 8 months after placement. Blinded assessors evaluated peri-implant bone and soft-tissue levels. RESULTS Fifty-two implants were immediately loaded and 52 were early loaded. No drop-out occurred. One single immediately loaded implant failed 2 months after placement. Both groups gradually lost peri-implant bone in a highly statistically significant manner at 2, 8, and 14 months. After 14 months, patients of both groups lost an average of 1.1 mm of peri-implant bone. There were no statistically significant differences between the two loading strategies for peri-implant bone and soft-tissue level changes (P > 0.05). After 14 months, the position of the soft tissues did not change significantly from baseline (delivery of the final restorations 8 months after placement). CONCLUSIONS There were no statistically or clinically significant differences between immediate and early loading of dental implants with regard to peri-implant bone and soft-tissue levels as evaluated in the present study.

Maxillary sinus elevation by lateral window approach : evolution of technology and technique

CONTEXT The maxillary sinus elevation procedure has become an important pre-prosthetic surgical procedure for the creation of bone volume in the edentulous posterior maxilla for the placement of dental implants. Research and clinical experience over the past 30 years has increased the predictability of this procedure as well as reduced patient morbidity. EVIDENCE ACQUISITION Data on grafting materials and implant survival rates comes from 10 published evidence-based reviews that include all relevant published data from 1980 to 2012. Supporting clinical material comes from the experience of the authors. EVIDENCE SYNTHESIS The evidence-based reviews report and compare the implant survival rates utilizing various grafting materials, implant surfaces, and the use or non-use of barrier membranes over the lateral window. Clinical studies report on complication rates utilizing piezoelectric surgery and compare them to complication rates with rotary instrumentation. CONCLUSIONS The conclusions of all the evidence-based reviews indicate that the utilization of bone replacement grafts, rough-surfaced implants, and barrier membranes result in the most positive outcomes when considering implant survival. Further, the utilization of piezoelectric surgery, rather than rotary diamond burs, for lateral window preparation and membrane separation leads to a dramatic reduction in the occurrence of the intraoperative complications of bleeding and membrane perforation.

Anatomic assessment of the anterior mandible and relative hemorrhage risk in implant dentistry: a cadaveric study

OBJECTIVES To evaluate prevalence, size, location and content of foramina and bony canals located on the lingual side of the mandibular midline. MATERIAL AND METHODS The prevalence and the size of midline lingual foramina and canals visible above and/or below genial spines and their distances from the mandibular base were measured in 60 dry mandibles from adult human cadavers. In addition, macro-anatomic dissections were performed on another 20 mandibles injected with red latex to investigate the vascular canal contents associated with these midline lingual foramina and canals. RESULTS A total of 118 foramina were detected. All mandibles investigated had at least one lingual foramen at the midline above the genial spines, located at a mean height of 12.5+/-2.1 mm (SD) from the inferior border of the mandible. Macro-anatomic dissections showed a clear vascular branch entering the mandibular midline as a single vessel from a sublingual-sublingual anastomosis in 19 out of 20 mandibles studied (95%). CONCLUSION Blood vessels in the floor of the mouth may be in close proximity to the lingual cortical plate of the mandibular midline in most cases. This implies that bleeding can occur when the mandibular cortical plate is perforated even minimally. As a consequence, the authors suggest a careful planning of implant positioning at mandibular midline, possibly opting for the use of an even number of implants in the interforaminal region, avoiding the risk of surgical trauma to the lingual cortical plate of the mandibular midline.

Immediate occlusal loading the same day or the after implant placement: comparison of 2 different time frames in total edentulous lower jaws.

Immediate loading of endosseous implants is becoming a widespread therapeutic procedure for the rehabilitation of patients with edentulous jaws. The purpose of this prospective clinical trial was to evaluate the long-term success rate of endosseous implants placed in the edentulous lower jaw and loaded on either the same day of surgery or the next day. Nineteen patients were enrolled in the study. Eleven patients, accounting for 64 implants, received their provisional prosthesis the same day of implant placement, and 8 patients, accounting for 52 implants, were rehabilitated the day after surgery. All patients were rehabilitated by a hybrid prosthesis supported by 5 to 6 Osseotite implants. Two implants failed in the group of patients who had their implants loaded the same day (96.9% success rate), whereas 1 implant failed in the other group (98.1% success rate). The overall implant success rate was 97.4%. All failures occurred within 2 months of function. No other complication was reported. The mean follow-up for this interim report was 37.8 +/- 16.5 months (range 8-65 months). Crestal bone loss was similar to that reported for standard delayed loading protocols. The results of this study suggest that the rehabilitation of the edentulous lower jaw by an immediate occlusally loaded implant-supported hybrid prosthesis is equally successful when loading is applied the same day or the day after implant placement. Immediate loading with 5 to 6 implant-supported prostheses represents a viable alternative treatment to classic delayed loading protocols.