Treatment Outcome of Two Adjacent Implant-Supported Restorations with Different Implant Platform Designs in the Esthetic Region: A Five-Year Randomized Clinical Trial.

PURPOSE: The aim of this study was to evaluate the peri-implant soft and hard tissues and satisfaction in patients with two adjacent implant-supported restorations in the esthetic region, treated with two adjacent implants with a scalloped or flat platform. MATERIALS AND METHODS: The randomized clinical trial consisted of 40 patients allocated to either a scalloped implant group consisting of 20 patients or a flat implant group of 20 patients. Clinical and radiographic examinations were performed during a 5-year followup period, and patient satisfaction during the same period was assessed. RESULTS: The scalloped implant group showed significantly more marginal bone loss (scalloped: 3.2 ± 1.1 mm; flat: 1.5 ± 0.8 mm) and significantly greater bone loss at the interimplant bone crest (scalloped: 2.4 ± 1.0 mm; flat: 1.3 ± 1.0 mm). Furthermore, peri-implant soft tissues showed significantly more bleeding when provided with scalloped implants than with flat implants. Papilla index scores were low in both groups. Patient satisfaction was high in both groups. CONCLUSION: More bone loss and compromised interimplant papilla regeneration were noted around scalloped implants in the first year, and stable results were observed in the subsequent 4 years with both systems. Scalloped implants seem to offer no benefit when compared to conventional flat implants in the esthetic region.

Changes in crestal bone around endosseous implants during functional loading: a radiographic evaluation in edentulous patients comparing different implant designs.

Marginal bone changes around titanium plasma-sprayed implants (n = 240) placed in the mandibular interforaminal regions of 120 edentulous patients were assessed over 5 years of follow-up, with emphasis on the influence of the locations of the microgap and rough/smooth border. Marginal bone changes were measured on standardized radiographs. Locations of the microgap and the rough/smooth border were both shown not to be major contributing factors in determining the marginal bone level around implants.

Single implants with different neck designs in the aesthetic zone: a randomized clinical trial.

OBJECTIVES: To compare single implants in the aesthetic zone with different neck designs for marginal bone-level changes and clinical outcome measures. MATERIALS AND METHODS: Ninety-three patients with a missing anterior tooth in the maxilla were randomly assigned to be treated with an implant with a 1.5 mm smooth neck ("smooth group"), a moderately rough neck with grooves ("rough group") or a scalloped moderately rough neck with grooves ("scalloped-group"). Implants were installed in healed sites and were loaded after 3 months. Follow-up visits were conducted at 6 and 18 months after implant placement. RESULTS: The scalloped group showed significantly more radiographic bone loss from implant placement to 18 months (2.01 ± 0.77 mm) compared with the smooth group (1.19 ± 0.82 mm) and rough group (0.9 ± 0.57 mm). Furthermore the scalloped group showed significantly deeper pocket depths and a higher bleeding score. There were no between-group differences in soft tissue levels. Survival rates were 97% for the smooth group and 100% for the rough and scalloped groups (P>0.05). No significant differences in outcome were found between the smooth group and rough group. CONCLUSION: For anterior tooth replacements, implants with a scalloped neck showed more marginal bone loss and less favourable clinical outcome compared with implants with a 1.5 mm smooth neck or implants with a rough neck.

Dental implant treatment for two adjacent missing teeth in the maxillary aesthetic zone: a comparative pilot study and test of principle.

AIM: The aim of this prospective comparative pilot study was to evaluate hard and soft peri-implant tissues in patients with a missing adjacent central and lateral upper incisor treated with either one implant and an implant crown with a cantilever or two implants with solitary implant crowns up to 1 year after functional loading. MATERIAL AND METHODS: In the "Implant-cantilever group", five patients were treated with one dental implant in the region of the central incisor (NobelReplace Groovy Regular Platform). In the "Implant-implant group", five patients were treated with two adjacent dental implants: at the position of the central incisor (NobelReplace Groovy Regular Platform) and at the position of the lateral incisor (NobelReplace Groovy Narrow Platform). Implant survival, pocket probing depth, papilla index, marginal bone level and patient satisfaction were assessed during a 1-year follow-up period. RESULTS: No implants were lost during the 1-year follow-up. Mean pocket probing values of the implants were comparable between the two groups. Papilla index scores in both groups were relatively low, pointing towards a compromised papilla. Marginal bone loss was minimal and comparable between the groups. Patient satisfaction was very high in both groups. CONCLUSION: In this 1-year prospective comparative study, no large differences in hard- and soft-tissue levels could be shown between patients with a missing central and lateral upper incisor treated with either one implant and an implant crown with a cantilever or two implants with solitary implant crowns.

Treatment outcome of two adjacent implant crowns with different implant platform designs in the aesthetic zone: a 1-year randomized clinical trial.

AIM: To evaluate the peri-implant tissues in patients with two adjacent implant crowns in the aesthetic zone, treated with either two adjacent implants with a scalloped platform or with a flat platform. MATERIAL AND METHODS: Forty patients were randomly allocated to: (1) a "scalloped implant group": 20 patients treated with two adjacent implants with a scalloped platform, and (2) a "flat implant group": 20 patients treated with two adjacent implants with a flat platform. Clinical and radiographic examinations were performed during a 1-year follow-up period to assess hard and soft tissue changes. RESULTS: The scalloped implant group showed significantly more marginal bone loss (scalloped: 2.7±1.4 mm, flat: 0.9±0.8 mm) and more inter-implant bone crest loss (scalloped: 1.8±1.4, flat: 1.0±0.9 mm) than the flat implant group. There was no significant difference between the groups with regard to the papilla index and patients' satisfaction. CONCLUSION: After 1 year of function, there was more bone loss around scalloped implants than around flat implants. With regard to the presence of papilla, there were no differences between the groups. With both applied implant designs, it is difficult to establish a predictable and harmonious aesthetic result, especially regarding the peri-implant mucosa. Patients were very satisfied with the aesthetic outcome of the adjacent implants irrespective of the treatment concept applied.

Treatment outcome and patient satisfaction with two adjacent implant-supported restorations in the esthetic zone.

The purpose of this study was to evaluate the clinical and radiographic parameters as well as the esthetic outcome of two adjacent implant-supported restorations and the surrounding peri-implant mucosa in the maxillary esthetic zone. Ten patients were treated with two adjacent implants in the anterior maxillary zone according to the same protocol. Only patients who had been subjected to a separate previous augmentation procedure with autogenous bone were included in this study. The following parameters were analyzed: implant survival, marginal bone level, vertical distance between the contact point and the bone crest, Papilla Index, probing depth, Aesthetic Index, and patient satisfaction. Implant survival was 100%. The interimplant bone crest level was positioned significantly more apical than the bone crest level between the implant and its neighboring tooth. In addition, complete filling of the interproximal space was observed between two adjacent implant-supported restorations in only 1 of 10 patients, whereas the papilla between the implant and its neighboring natural tooth was present in 70% of patients. Furthermore, patients rated the esthetic outcome of their implant-supported restorations and the surrounding mucosa in all cases as "acceptable," while the clinicians, using the Implant Crown Aesthetic Index, determined six to be "acceptable" and four "unacceptable." Although many patients were satisfied with the esthetic result, it is difficult to establish an acceptable esthetic result with two adjacent implant-supported restorations in the esthetic zone in patients who needed a separate augmentation procedure, according to the contemporary standards of dental professionals.

Posterior mandibular residual ridge resorption in patients with overdentures supported by two or four endosseous implants in a 10-year prospective comparative study.

PURPOSE: The aim of this study was to evaluate the effect of treatment with either two or four mandibular endosseous implants with an overdenture on mandibular posterior residual ridge resorption over a 10-year period. MATERIALS AND METHODS: Sixty edentulous patients with residual mandibular height between 12 and 18 mm participated. Thirty patients were treated with an overdenture supported by two IMZ implants (group A) and 30 patients were treated with an overdenture with four IMZ implants (group B). Before treatment and 10 years after treatment, panoramic radiographs were taken and compared to ascertain possible bone loss. Proportional area measurements were used to determine changes in the mandibular posterior residual ridge bilaterally. RESULTS: There was a statistically significant difference in mandibular posterior residual ridge resorption between the two treatment protocols. The posterior bone area index was reduced by a mean of 10% for group A and 6% for group B over 10 years. CONCLUSIONS: There was a significant difference in mandibular posterior residual ridge resorption between patients treated with either two or four implants to stabilize an overdenture. No correlation was shown between mandibular posterior residual ridge resorption and peri-implant marginal bone loss. The confounding factors of marginal bone loss around the implants, age, gender, initial mandibular height, and the number of years the patient had been edentulous failed to show a significant effect on posterior ridge resorption.