Long-term outcomes of dental implants placed in elderly patients: a retrospective clinical and radiographic analysis.

OBJECTIVES: The aim of this retrospective study was to determine the clinical and the radiographic outcomes of dental implants placed in elderly people older than 65 years. MATERIALS AND METHODS: In total, 902 implants in 346 patients (age: 65-89 years) were followed up for 2-17 years following the implant surgery. The survival rate of these implants was recorded and analyzed. Changes in marginal bone levels were also analyzed in serial radiographs, and Cox regression analysis for implant loss was performed. RESULTS: The survival rates were 95.39% and 99.98% in the implant- and patient-based analyses, respectively (involving a total of 29 implant failures), and the marginal bone loss at the implants was 0.17 ± 0.71 mm (mean ± SD). The number of failures was greatest in patients aged 65-69 years. The Cox regression with shared frailty analysis showed that implant loss was significantly greater in those aged 65-69 years than in those aged 70-74 years (P < 0.05), and it varied between specific implant systems. CONCLUSIONS: Within the limitations of this retrospective study, it was concluded that implant therapy can be successfully provided to elderly patients and that age alone does not seem to affect the implant survival rate.

Long-term evaluation of sinus floor elevation using a modified lateral approach in the posterior maxilla.

OBJECTIVES: The aim of this study was to evaluate the hybrid technique, which was modified from the lateral approach in sinus elevation by combining transalveolar access. MATERIALS AND METHODS: Sixty patients (mean age of 53.3 ± 11.6 years) with 105 implants placed in the posterior maxilla with the average remaining bone height (RBH) of 4.3 ± 1.8 mm (range of 1.2-9.2 mm) were enrolled in the hybrid group and followed up for 96 months. The control group included 36 patients with 44 implants placed in the corresponding site with sufficient RBH. Cumulative survival rate (CSR), radiographic measurements in RBH, augmented bone height (ABH), and marginal bone loss (MBL) were analyzed during the follow-up period. RESULTS: Cumulative survival rate in the hybrid group was 98.1%, which was comparable to the control group (97.7%). MBL of the mesial and distal aspects in the hybrid group (0.28 ± 0.66 mm and 0.41 ± 0.93 mm, respectively) was comparable to the control group (0.84 ± 1.11 mm and 0.76 ± 0.88 mm, respectively). In the hybrid group, the membrane perforation rate during the surgery was 4.5%. ABH was 8.3 ± 1.8 mm after the surgery and maintained consistently during the follow-up period (7.4 ± 1.9 mm after 4 years). CONCLUSION: The hybrid technique is a simple and predictable surgical method for simultaneous placement of a dental implant with sinus floor elevation regardless of the RBH.

Erratum: Body text. Bone formation around rhBMP-2-coated implants in rabbit sinuses with or without absorbable collagen sponge grafting.

[This corrects the article on p. 238 in vol. 45, PMID: 26734494.].

Application of a Collagenated Biphasic Calcium Phosphate Loaded with Fibroblast Growth Factor-2 in the Rabbit Sinus: A Pilot Study.

PURPOSE: The aim of this study was to determine the effect of collagenated biphasic calcium phosphate (CBCP) loaded with fibroblast growth factor-2 (FGF-2) on bone regeneration in a rabbit sinus model. MATERIALS AND METHODS: Bilateral sinus augmentations were performed using either FGF-2-loaded CBCP (FGF-2 group) or CBCP only (control group) in 10 rabbits. The experimental animals were euthanized at 2 weeks (n = 5) or 4 weeks (n = 5) postoperatively. Volumetric analyses were done by means of microcomputed tomography and histomorphometry. RESULTS: The volumes of total augmentation, new bone, residual material, and fibrovascular tissue were significantly greater in the FGF-2 group than in the control group at 2 weeks, but the differences between the two groups had disappeared by 4 weeks. Histologically, the healing patterns, such as new bone formation and the resorption of residual material, did not differ notably between the two groups. The results of the histometric analysis did not correspond to those of the volumetric analysis. The areas of total augmentation, new bone, residual material, and fibrovascular tissue, and the number of blood vessels did not differ significantly between the FGF-2 and the control groups at either time point. CONCLUSION: CBCP loaded with FGF-2 resulted in the early promotion of new bone; however, it failed to produce superior bone regeneration in a later stage of healing.

Assessment of dehydrothermally cross-linked collagen membrane for guided bone regeneration around peri-implant dehiscence defects: a randomized single-blinded clinical trial.

PURPOSE: The aim of this study was to determine the clinical feasibility of using dehydrothermally cross-linked collagen membrane (DCM) for bone regeneration around peri-implant dehiscence defects, and compare it with non-cross-linked native collagen membrane (NCM). METHODS: Dehiscence defects were investigated in twenty-eight patients. Defect width and height were measured by periodontal probe immediately following implant placement (baseline) and 16 weeks afterward. Membrane manipulation and maintenance were clinically assessed by means of the visual analogue scale score at baseline. Changes in horizontal thickness at 1 mm, 2 mm, and 3 mm below the top of the implant platform and the average bone density were assessed by cone-beam computed tomography at 16 weeks. Degradation of membrane was histologically observed in the soft tissue around the implant prior to re-entry surgery. RESULTS: Five defect sites (two sites in the NCM group and three sites in the DCM group) showed soft-tissue dehiscence defects and membrane exposure during the early healing period, but there were no symptoms or signs of severe complications during the experimental postoperative period. Significant clinical and radiological improvements were found in all parameters with both types of collagen membrane. Partially resorbed membrane leaflets were only observed histologically in the DCM group. CONCLUSIONS: These findings suggest that, compared with NCM, DCM has a similar clinical expediency and possesses more stable maintenance properties. Therefore, it could be used effectively in guided bone regeneration around dehiscence-type defects.

Bone formation around rhBMP-2-coated implants in rabbit sinuses with or without absorbable collagen sponge grafting.

PURPOSE: The purpose of this study was to evaluate bone formation around recombinant human bone morphogenetic protein (rhBMP-2)-coated implants placed with or without absorbable collagen sponge (ACS) in rabbit maxillary sinuses. METHODS: The Schneiderian membrane was elevated and an implant was placed in 24 sinuses in 12 rabbits. The space created beneath the elevated membrane was filled with either blood (n=6) or ACS (n=6). In the rabbits in which this space was filled with blood, rhBMP-2-coated and non-coated implants were alternately placed on different sides. The resulting groups were referred to as the BC and BN groups, respectively. The AC and AN groups were produced in ACS-grafted rabbits in the same manner. Radiographic and histomorphometric analyses were performed after eight weeks of healing. RESULTS: In micro-computed tomography analysis, the total augmented volume and new bone volume were significantly greater in the ACS-grafted sinuses than in the blood-filled sinuses (P<0.05). The histometric analysis showed that the areas of new bone and bone-to-implant contact were significantly larger in the AC group than in the AN group (P<0.05). In contrast, none of the parameters differed significantly between the BC and BN groups. CONCLUSIONS: The results of this pilot study indicate that the insertion of ACS after elevating the Schneiderian membrane, simultaneously with implant placement, can significantly increase the volume of the augmentation. However, in the present study, the rhBMP-2 coating exhibited limited effectiveness in enhancing the quantity and quality of regenerated bone.