Scientific rationale for the surgical and prosthodontic protocol for immediately loaded root form implants in the completely edentulous patient

Rehabilitation of the edentulous mandible with implant-supported overdentures on telescopic abutments and immediate loading. A controlled prospective clinical study

The rehabilitation of the edentulous mandible with implant-supported overdentures is an established clinical procedure but immediate loading of implants supporting mandibular overdentures has not been equally documented.

AIM

The aim of this prospective clinical study was to evaluate the rehabilitation of the edentulous mandible with immediate loading and implant-supported overdentures.

MATERIALS AND METHODS

10 patients were restored with immediate loading of the implants and 5 with delayed loading. The treatment planning included placement of four implants in the interforaminal area of the mandible. Prefabricated titanium abutments with 4 degrees of conical inclination were fixed on the implants and the telescoping conical caps were connected to the base of the mandibular denture. Bone loss was assessed by comparison of panoramic x-rays at baseline 3, 6, and 36 months by visual observation from clinicians.

RESULTS

A total of 60 implants were restored, 40 with immediate and 20 with delayed loading. The follow-up period ranged from 4 to 10 years with 72 months mean observation time. Prosthetic complications appeared with low frequency and no implant loss occurred during the follow-up period. No statistical significance was observed in the bone loss in the cervical area of the immediate and late loaded implants.

CLINICAL SIGNIFICANCE

The rehabilitation of the edentulous mandible with implant-supported overdentures and telescopic copings is a viable clinical solutions with multiple clinical advantages both for the clinician and the patient. . Immediate loading can be applied in cases where increased initial stability can be achieved. More extended long-term clinical studies with increased number of patients and implants are needed, however, to verify the efficacy of the treatment method.

Immediate loading of overdentures: systematic review

INTRODUCTION

The goal of implant treatment is the formation of a direct bone-implant interface contact.

PURPOSE

This study aimed to evaluate the possibilities of immediate loading treatment for edentulous patients rehabilitated with mandibular and maxillary overdentures.

MATERIAL AND METHODS

A literature review using the PubMed and BIREME databases between the periods of 1977 and 2011 was performed.

RESULTS

From an initial yield of 218 titles, 78 articles were selected for text analysis, finally resulting in 23 studies (16 prospective, 6 prospective randomized, and 1 prospective multicenter) that met the inclusion criteria.

CONCLUSION

The immediate loading protocol through which the implants are subjected to occlusal function immediately after their placement was introduced to overcome this limitation.

Resonance frequency analysis of overdenture retainer implants with immediate loading

OBJECTIVE

To evaluate 16 patients of both sexes with lower overdenture and upper complete dentures, by analysing the resonance frequency of the initial and late stability of implants used to retain the overdenture under immediate loading.

BACKGROUND

Oral rehabilitation treatment with complete dentures using implants has been increasingly more common among the specialists in the oral rehabilitation area. This is an alternative for obtaining retention and stability in treatments involving conventional complete dentures, where two implants are enough to retain the overdenture satisfactorily.

MATERIALS AND METHODS

The Osstell™ Mentor device was used for the analysis in the initial period (primary stability), 3 and 15 months after the installation of the lower overdenture (secondary stability). The statistical analysis was performed with the repeated measures model (p < 0.01).

RESULTS

The implant stability quotients were observed to increase after 15 months of the rehabilitating treatment.

CONCLUSION

The use of overdentures over two lower implants should become the treatment of choice for individuals who have a fully edentulous mandible.

The comparison of provisional luting agents and abutment surface roughness on the retention of provisional implant-supported crowns

STATEMENT OF PROBLEM

In immediate implant loading, it is important to keep provisional restorations in place during early-phase healing. Current luting agents for provisional restorations may provide inadequate retention, creating a clinical challenge.

PURPOSE

This study compared the retention of provisional autopolymerizing acrylic resin implant-supported single restorations with combinations of different implant abutment surface conditions and provisional luting agents.

MATERIAL AND METHODS

Thirty solid titanium implant abutments (ITI), 4 mm high, were divided into 3 groups. Ten abutments were unaltered, 10 were airborne-particle abraded with 50-microm aluminum oxide, and 10 were roughened with a medium-roughness diamond rotary cutting instrument. Thirty implant analogs (ITI) were mounted in autopolymerizing acrylic resin blocks. A solid titanium implant abutment was placed in each implant analog and torqued to 35 N.cm. After fabrication of 4 provisional acrylic resin crowns for each abutment, provisional luting agents TempBond, TempBond NE, Life, and Zone were used to secure the provisional crowns to the respective abutments. All specimens were luted with one of the provisional luting agents for a given test. After ultrasonic cleaning of the abutments, another provisional crown was luted with another luting agent. All specimens were stored in 100% humidity environment for 1 day at 37 degrees C prior to testing. Each provisional acrylic resin crown was pulled from the abutment with a 500-kg load cell in a universal testing machine at a crosshead speed of 0.5 cm/minute, and tensile strength was recorded (N). Data were analyzed using analysis of variance (ANOVA) and the Scheffe test (alpha=.05).

RESULTS

Tensile strength was significantly higher for Life and TempBond NE than for TempBond and Zone, regardless of the surface conditions (P=.0001). The result of the 2-way ANOVA indicated that a significant interaction existed between the provisional luting agents and surface conditions (P=.0039). TempBond NE showed significantly higher tensile strength when combined with airborne-particle-abraded surfaces compared to other combinations (P=.011). However, no difference was found in tensile strength of Life and Zone between different combinations. The tensile strength of TempBond was lower when used with the unaltered surface compared to other combinations (P=.001).

CONCLUSION

Surface modification of an implant abutment by airborne-particle abrasion or diamond rotary cutting instrument did not improve retention of a provisional acrylic crown when Life or Zone was used as the luting agent. Airborne-particle abrasion may be an effective method to increase retention of a provisional acrylic crown when TempBond NE is used.

Functional Restoration of Implants on the Day of Surgical Placement in the Fully Edentulous Mandible: A Case Series

PURPOSE

The purpose of this article is to report the clinical experience and outcome of a study of the functional rehabilitation of 16 completely edentulous mandibles with immediately loaded cross-arch screw-retained hybrid prostheses at the University of Southern California.

MATERIALS AND METHODS

After signing informed consent forms 16 patients (9 male, 7 female) aged 47 to 84 years (mean age, 62.6+/-11.6 years) received 90 Brånemark System Mk III dental implants (Nobel Biocare USA, Yorba Linda, CA, USA). Stability and radiographs of the dental implants were evaluated at the time of surgery, at 3 months, at 1 year, and at 3 years post loading.

RESULTS

Three implants failed to meet the criteria of success, bringing the cumulative success rate to 96.6%, with a 100% prosthetic success rate at 3 years. Thirty-nine (43.3%) of the dental implants placed were 15 mm in length. Seventy-seven (85.5%) of the dental implants were placed in high-density bone. At 3 years post loading, the average bone loss was -1.2+/-0.1 mm.

CONCLUSION

Within the limitations of this study, restoration of implants by unreinforced hybrid prostheses at the time of placement provided satisfactory results. The outcome was stable at 3 years post restoration. Mandibular rehabilitation by functional loading of the implants on the day of the insertion requires the comprehension and proper application of surgical and restorative principles.

Immediate Occlusal Loading the Same Day or the Day After Implant Placement: Comparison of 2 Different Time Frames in Totally 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.

Present Status of Immediate Loading of Oral Implants

PROBLEM

Several conditions must be present to obtain implant integration and long-term clinical success when using the one-stage implant placement procedure with immediate loading. These conditions include (1) primary stability, (2) sufficient bone quality, and (3) elimination of micromovement of the implant before osseous integration is complete.

PURPOSE

This report presents the results of research on immediate loading using a new and innovative implant design, Ankylos.

METHODS

The author reviewed clinical studies of immediate loaading or oral implants, including two treatment options, removable overdentures and fixed reconstructions.

RESULTS

Animal studies have demonstrated that successful osseointegration of Ankylos implants can occur (Figure 2D) when implants are placed and loaded immediately in the presence of some specific conditions. The histological findings involving implants that were placed in humans and immediately loaded showed no fibrous tissue formation (encapsulation). The bone-to-implant contact (osseointegration) was found to be excellent between the immediately-loaded implants and the surrounding alveolar bone.

CONCLUSION

The Ankylos implant system with its progressive thread design successfully promotes primary, clinical stability at the time of implant placement. Several animal studies have shown that in implant restorations placed in similar areas of poor bone quality (ie, maxilla and the posterior part of the mandible), the concept of immediate loading can result in long-term clinical success, when loading forces are controlled. Immobilization of the implants and soft diet recommendations that reduce micromovement at the bone-to-implant interface will improve long-term clinical success. In summary, the Ankylos implant is well designed for one-stage placement with immediate loading, as well as for two-stage treatment protocols. Both clinical protocols will result in long-term clinical survival.

Immediate occlusal loading of Osseotite implants in the lower edentulous jaw. A multicenter prospective study

OBJECTIVE

This paper reports the results of a prospective multicenter clinical study on immediately fully occlusally loaded full-arch screw-retained prostheses with distal extensions (hybrid prostheses) supported by Osseotite implants inserted in edentulous lower jaws.

METHOD AND MATERIAL

Sixty-two patients were enrolled in four clinical centers. Three hundred and twenty-five Osseotite implants were inserted and occlusally loaded according to an immediate loading protocol. The temporary prosthesis was delivered 4 h from surgery. The final prosthesis was delivered after 6 months. Marginal bone loss was monitored from periapical radiographs using a computerized technique.

RESULTS

Two implants failed to integrate within 2 months of occlusal loading. A cumulative implant success rate of 99.4% was achieved for a period of 12-60 months postplacement (mean 28.6+/-14.1 (SD) months). Crestal bone loss around the immediately loaded implants was similar to that reported for standard delayed loading protocols.

CONCLUSION

The results of this study suggest that the rehabilitation of the edentulous mandible by an immediate occlusally loaded hybrid prosthesis supported by five to six Osseotite implants represents a viable alternative treatment to classic delayed loading protocols.

Treatment of Advanced Periodontal Destruction With Immediately Loaded Implants and Simultaneous Bone Augmentation: A Case Report

BACKGROUND

Advanced periodontal destruction is often associated with extraction of the teeth. Oral rehabilitation in these cases may include the traditional prosthetic restoration or an implant-supported reconstruction. Immediately loaded implants present an alternative treatment modality using a bar in the anterior mandible, along with the placement of higher numbers of implants, which are connected with a fixed prosthetic reconstruction.

METHODS

This clinical case report presents the surgical and prosthetic rehabilitation in a patient who had lost all teeth due to advanced periodontal bone destruction. Six implants were placed in the upper and lower jaw each. Some implants required guided bone regeneration in conjunction with autologous bone grafting. All of the implants were connected with their abutments, and a temporary fixed restoration was placed immediately after surgery. The final metalloceramic-fixed reconstruction was cemented after 6 weeks of loading.

RESULTS

All of the implants were osseointegrated and showed no clinical signs of mobility or infection. Mobility values were evaluated during healing and were found to be reduced. Radiological findings showed a stable peri-implant bone level during the total 18-month loading observation period.

CONCLUSIONS

This case report presents an alternative treatment concept for the oral rehabilitation in a patient with advanced periodontal destruction. The concept of immediate loading of implants might provide a better opportunity to meet patient needs than more traditional treatment modalities.

One-year prospective evaluation of the early loading of unsplinted conical Brånemark fixtures with mandibular overdentures immediately following surgery

BACKGROUND

Prospective evaluation of the early loading of unsplinted Brånemark implants with mandibular overdentures opposing conventional dentures is not evident in the implant-related literature.

PURPOSE

To clinically evaluate progressive and early loading of 20 unsplinted conical Brånemark implants in edentulous mandibles with overdentures.

MATERIALS AND METHODS

Ten edentulous patients all had two conical Brånemark implants placed in the anterior mandible with mandatory primary stability with bicortical anchorage. Ball abutment connection was performed simultaneously. Previously constructed conventional mandibular dentures were temporarily relined with tissue conditioner postoperatively and worn with moderation for the first 2 weeks to allow progressive loading. Early loading of the implants followed after 2 weeks, with inclusion of the respective matrices in the mandibular dentures, using a definitive reline procedure.

RESULTS

All patients successfully functioned with their mandibular implant overdentures from 2 to 52 weeks postoperatively. Mean marginal bone loss was within established criteria for success: 0.22 mm (SD = 0.48 mm) mesially and 0.30 mm (SD = 0.39 mm) distally on the conical implants. Mobility tests using the Periotest instrument became more negative, although not at statistically significant levels. Difficulties in the management of the peri-implant mucosa between surgery and loading at 2 weeks were observed in 40% of the patients.

CONCLUSIONS

These preliminary 1-year results show that successful early loading of unsplinted conical Brånemark implants with mandibular overdentures is possible.