Prospective 10-year cohort study based on a randomized, controlled trial (RCT) on implant-supported full-arch maxillary prostheses. part II: prosthetic outcomes and maintenance.

BACKGROUND: Long-term follow-up studies (i.e., over 5 years), focusing on prosthetic outcomes and maintenance of implant-supported reconstructions in the edentulous maxilla, are scarce in the literature. PURPOSE: The purpose of this study was to evaluate and report 10-year data on outcomes and maintenance of screw-retained implant-supported full-arch casted titanium-resin prostheses in the edentulous maxilla. MATERIALS AND METHODS: In the randomized control trial cohort of 24 patients, the outcome and maintenance of 23 bridges were registered. RESULTS: One patient dropped out of the study prior to the 10-year control. Of the 23 remaining patients, 21 still had their original frameworks; one framework fractured after 8 years and one was remade after 7 years to create better support for the acrylic. The remaining 23 prostheses showed criteria of success, survival, and failure in 9, 82, and 9%, respectively. Tightening of two assembly screws was necessary in one patient. No detrimental effects were seen because of long cantilever extensions or opposing dentition. A total of 4.7 resin-related complications per prosthesis were observed; tooth fracture was the most common prosthetic complication. There was an indication of greater prevention in the number of resin-related complications with the use of lingual gold onlay compared with a resilient mouth guard, 0.71 and 1.67, respectively per bridge. The bridges were removed and reinserted 0.83 times per patient. No abutment or abutment screw fractures were registered. CONCLUSION: Fracture or wear of the reconstruction materials were considered predictable risks when using resin-based suprastructure materials. Status of opposing dentition and length of cantilevers did not confer additional risk. The use of a lingual gold onlay indicated prevention of resin-related complications. Future research should focus on the suprastructure materials to predict better overall treatment results of implant-supported full-arch bridges in the edentulous maxilla.

Prospective 10-year cohort study based on a randomized controlled trial (RCT) on implant-supported full-arch maxillary prostheses. Part 1: sandblasted and acid-etched implants and mucosal tissue.

BACKGROUND: There have been very few long-term controlled studies (i.e., over 5 years duration) focusing on marginal conditions for implants with a sandblasted, large grit, and acid-etched (SLA) surface. PURPOSE: To evaluate and report 10-year data on outcomes of implants with an SLA surface placed in the edentulous maxilla. MATERIALS AND METHODS: In a randomized controlled trial (RCT) cohort of 24 patients, the outcomes of implants with an SLA surface were registered. The RCT cohort has previously been reported after 1 year, 3 years, and 5 years of loading. RESULTS: One patient dropped out of the study prior to the 10-year control. Of the 23 remaining patients, the implant survival rate was 95.1%. If implants of unknown status were also considered lost, that is, one drop-out patient with three implants for whom no information could be obtained, the implant survival rate was 93%. The mean marginal bone loss from baseline (139 implants) to 10 years (102 implants) was 1.07 mm (standard deviation 0.98). One implant out of 102 available for radiographic examination according to the original protocol showed a bone loss exceeding 4 mm. Of the 84 implants available for clinical examination, none showed a Plaque Index or sulcus bleeding index of 3. The mean implant stability quotient was significantly higher for mesial-distal versus buccal-palatal measurements. CONCLUSION: The implant survival was 95.1%. The mean value of bone loss after 10 years was 1.07 mm. Peri-implantitis were noted at the 5-year follow-up for one patient with a previous history of periodontitis; this patient did not attend the 10-year follow-up. This study shows that sandblasted and acid-etched implants offers predictable long-term results as support for full-arch maxillary prostheses.

Five-year results from a randomized, controlled trial on early and delayed loading of implants supporting full-arch prosthesis in the edentulous maxilla.

OBJECTIVES: The overall aim was to compare the clinical outcomes of early and delayed implant loading in the totally edentulous maxilla during 5 years of function. MATERIALS AND METHODS: Twenty-four patients with edentulous maxillae were randomized in two groups and subjected to early (test, n=16) or delayed (control, n=8) loading. A total of 142 implants were placed and 139 implants (Straumann AG) were loaded with full-arch bridges and followed for 5 years. RESULTS: All patients received and maintained a fixed bridge throughout the study period. Five (5.3%) test implants in three patients and two (4.3%) control implants in two patients were lost during the 5 years (NS). There were no differences in implant stability as measured with resonance frequency analysis at 5 years. More bone loss occurred at test than at control implants, -0.8 mm (SD 1.2) vs. -0.3 mm (SD 1.1), respectively. However, test implants showed a more coronal marginal bone level than control implants after 5 years, 2.9 mm (SD 1.1) vs. 3.7 mm (SD 1.2) from the implant shoulder, respectively. No control implants and four (4.4%) test implants in three (18.8%) patients showed >3 mm bone loss after 5 years. Two of the latter implants in one patient also showed increased probing depths, bleeding at probing and plaque accumulation. Tooth fracture was the most common prosthetic complication. The use of lingual gold onlay effectively reduced the number of resin-related complications as opposed to a resilient mouth guard. CONCLUSIONS: The present randomized controlled trial showed no important differences between early and delayed loading of implants in the edentulous maxilla after 5 years of function. A favourable long-term marginal bone response to the sandblasted large-grit acid-etched (SLA) surface was observed. Technical complications were mainly resin-related which could be avoided by the use of a lingual gold onlay. It is concluded that early loading of SLA-surface implants for support of full-arch bridges represents a viable therapy for the totally edentulous maxilla.

Three-year data from a randomizd, controlled study of early loading of single-stage dental implants supporting maxillary full-arch prostheses.

PURPOSE: The aim of this 3-year randomized controlled trial (RCT) was to compare biologic and technical treatment outcomes and patient satisfaction after early (< or = 14 days postimplantation) loaded implants with those of implants loaded after a healing period of 3 to 4 months in the edentulous maxilla. MATERIALS AND METHODS: Twenty-four patients with completely edentulous maxillae were randomized into a test group (n = 16) and a control group (n = 8). All patients received 5 or 6 solid screw-type titanium implants with sandblasted, large-grit, acid-etched (SLA) surfaces. In total, 142 implants were placed and 139 implants were loaded with full-arch prostheses. Clinical assessments were obtained at loading and after 3, 6, 12, 24, and 36 months. Radiographs of implants and existing teeth were taken at loading; after 6, 12, 24, and 36 months; and at 12, 24, and 36 months, respectively. RESULTS: The cumulative implant success rate 3 years after loading was 100%. At the 3-year examination the mean (P < or = .005), distal (P < or = .005), and mesial (P > .05) crestal bone levels were better in the test group. No significant differences between the test and control groups were noted for any other outcome measure. The most common adverse event in both groups was tooth-crown fracture. DISCUSSION: A review of the literature, both printed and electronic, revealed no study fulfilling the criteria of an RCT dealing with the early loading of maxillary full-arch prostheses. This study fulfills those criteria. CONCLUSION: In this study population it has been concluded that the early (approximately 2 weeks) loading protocol is a viable alternative to the standard (3 to 4 months) protocol in the rehabilitation of a completely edentulous maxilla with a complete implant-supported fixed prosthesis.

Early loading of ITI implants supporting a maxillary full-arch prosthesis: 1-year data of a prospective, randomized study.

PURPOSE: This prospective, randomized study investigated the safety, feasibility, and reliability of the early loading of implants in edentulous maxillae. MATERIALS AND METHODS: Twenty-four patients with completely edentulous maxillae were randomized into a test group (n = 16) and a control group (n = 8). All patients received 5 or 6 solid screw-type titanium implants. These were loaded with full-arch prostheses after 9 to 18 days in the test group and after 2.5 to 5.1 months in the control group. Periapical radiographs were taken and routine clinical assessments were made at loading, after 6 months, and after 12 months. RESULTS: The implant survival rate 1 year after loading was 100%. Modified Plaque index scores and Sulcus Bleeding index scores were better in the test group than in the control group (P < or = .05). There was a significant difference in peri-implant bone height between the 2 groups (P < .001) and this difference converged with time (P < .001). DISCUSSION: This clinical, prospective, randomized, controlled study fulfilled the criteria for a comparable study. Owing to the small patient sample, the conclusions drawn were based on feasibility analyses of the results. Standard materials and methods were used. Only patients with maxillary bone of sufficient height and width were selected. The use of a single operator in each discipline--maxillofacial surgery, prosthodontics, and dental technology--may have improved the chances of achieving consistent standards and opinions. CONCLUSION: These results indicate that early loading in selected patients was as safe and reliable as delayed loading in this small patient population and may offer a satisfactory alternative to the standard protocol.