Search

Objectives: The objective of this study was to assess the difference in success rates of implants when using two or four implant-supported-overdentures following segmental mandibular reconstruction with fibula free flap., Methods and Designs: This prospective, parallel designed, randomized clinical study was conducted with 1:1 ratio. At baseline, all participants already had segmental reconstruction of mandible with free fibula flap. The participants were randomized into two groups: Group-I received implant-supported-overdentures on two tissue-level implants and Group-II received implant-supported-overdentures on four tissue-level implants. Success rates of the implants were evaluated at 3 months, 6 months and 12 months following implant loading using marginal bone level changes as well as peri-implant indices (Buser et al., 1990)., Results: 52 patients were randomized into two treatment groups (26 each), out of which 18 patients (36 implants) of Group-I and 17 patients (68 implants) of Group-II were evaluated. One implant in Group-I was lost due to infective complications and one patient in the same group had superior barrel necrosis. There was a statistically significant increase at both time points (p = 0.03, p = 0.04 at 6 months, 12 months) in the amount of marginal bone loss in Group-I (0.4 mm, 0.5 mm at 6 months, 12 months) as compared to Group-II (0.1 mm, 0.2 mm at 6 months, 12 months). There were no clinically significant changes peri-implant parameters between both groups. Peri-implant soft tissue hyperplasia was seen in both groups, 32% of implants at 3-months, 26% at 6-months and 3% at 12-months follow-up., Conclusion: The results of this study show that patients with 2-implant-supported-overdentures had higher marginal bone loss as compared to patients with 4-implant-supported-overdentures. There were no clinically significant differences in peri-implant soft tissue factors in patients with 2- or 4-implant-supported-overdentures. Hyperplastic peri-implant tissues are common in the early implant-loading phase and tend to decrease over time under appropriate management., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: The primary objective of this study was to assess the difference in quality of life (QoL) in patients with dental rehabilitation using two or four implant-supported overdentures following segmental mandibulectomy defect reconstruction with fibula free flap., Material and Methods: This prospective, parallel designed, randomized clinical study was conducted with a 1:1 ratio. At baseline, all participants already had fibula flap reconstruction for segmental defects of the mandible and rehabilitation with conventional (non-implant supported) removable partial dentures. The participants were then randomized into two groups. Group I received implant supported overdentures on two implants, and Group II received four implants. QoL outcomes were evaluated using standardized questionnaires (EORTC_QLQ c30, H&N35, OHIP, DSI). Outcomes of treatment were evaluated at 6 months (T1) and 1 year (T2) following rehabilitation., Results: A total of 52 patients were randomized into two treatment groups (26 each). After accounting for the loss to lack of follow-up, 22 patients in Group I and 24 patients in Group II were evaluated for QoL at the end of the study. There was a significant improvement in QoL with implant-assisted dental rehabilitation. However there were no significant differences in QoL between the two-implant and four-implant groups., Conclusion: Implant-supported removable overdentures improve QoL outcomes in patients with reconstructed mandibles. This study showed no significant difference in QoL outcomes in patients with two- or four-implant supported removable prostheses., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Large defects of the human face often cause esthetic as well as functional disorders. We present a new technique for reconstruction of the mandible with prosthodontic rehabilitation in a single surgery, using the implant-supported, bar-retained overdenture as an external fixator. A 58-year-old patient presented with a near total defect of the mandible after cancer resection. For rehabilitation, the mandibular condyles were virtually positioned in the centre of the fossae, and four dental implants were planned. The position of the fibula segments as well as their angulation and lengths were adapted to the implant position. To transfer this plan into surgery, a combined cutting/implant drilling guide was computer-aided printed. To provide the correct angulation of the fibula segments, a CAD/CAM dental arch-bar was made from titanium, fulfilling three functions: to bear the provisional prosthesis; to stabilize the molded fibula as an external fixator; and to position the complete fibula with the prosthesis in a correct relation to the upper jaw and occlusion, as indicated by the prosthesis. This innovative approach of combined prosthodontic and reconstructive rehabilitation could shorten the total reconstruction/rehabilitation time and avoid the need for additional extended surgeries., (Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: To compare the oral health-related quality of life (OHRQoL) in a prospective, randomized crossover trial in patients with mandibular overdentures retained with two or four locators., Materials and Methods: In 30 patients with edentulous mandibles, four implants (ICX-plus implants [Medentis Medical]) were placed in the intraforaminal area. Eight weeks after transgingival healing, patients were randomly assigned to have two or four implants incorporated in the prosthesis. After 3 months, the retention concepts were switched. The patients with a two-implant-supported overdenture had four implants incorporated, whereas patients with a four-implant-supported overdenture had two retention locators taken out. After 3 more months, all four implants were retained in the implant-supported overdenture in every patient. To measure OHRQoL of the patients, the Oral Health Impact Profile 14, German version (OHIP-14 G), was used., Results: A considerable increase in OHRQoL could be seen in all patients after the prosthesis was placed on the implants. Also, a statistically significant difference of OHRQoL could be seen in the OHIP-14 G scores between two-implant and four-implant overdentures. Patients had a higher OHRQoL after incorporation of four implants in the overdenture compared with only two implants., Conclusion: Patients with implant-retained overdentures had better OHRQoL compared with those with conventional dentures. The number of incorporated implants in the locator-retained overdenture also influenced the increase in OHRQoL, with four implants having a statistically significant advantage over two implants.

Purpose: To evaluate factors promoting mucositis and peri-implantitis (plaque accumulation, poor peri-implant soft tissue health, bone loss) with regard to prosthetic attachment systems consisting of implant-supported bar-retained overdentures., Materials and Methods: Patients who received TiOblast implants to support overdentures retained by either (1) prefabricated bars with or without extensions or (2) cast bars were recalled and examined clinically and radiographically. Plaque Index (PI), Sulcus Bleeding Index (SBI), probing pocket depth (PPD), and peri-implant bone loss were measured. Peri-implant tissue health was assessed, and the presence of mucositis and peri-implantitis was recorded. One-way analysis of variance with the Bonferroni adjustment was used to compare groups (α = .05)., Results: Five to 10 years after prosthetic loading, 107 patients who received 516 TiOblast implants were evaluated; 31 of these patients were treated with 131 implants to support bar-retained overdentures. PI, SBI, PPD, and pathologic bone loss were least common in the group with prefabricated bars, followed by the group with prefabricated bars with extensions, and were most common in the group with cast bars. Plaque accumulation and pathologic bone loss values were higher with implants that supported mandibular bar-retained overdentures than with those supporting maxillary bar-retained overdentures. However, these differences among attachment systems or between maxillary and mandibular implants were not significant (P > .05). Mucositis was observed in one implant in the group with prefabricated bars, four implants in the group with prefabricated bars with extensions, and four implants in the group with cast bars. Peri-implantitis was observed in one implant of the cast bar group., Conclusions: Five to 10 years after prosthetic loading, no significant difference in PI, SBI, PPD, pathologic bone loss, or peri-implant tissue conditions among the different bar designs tested was observed.

Purpose: Long-term results in the clinical outcome of different implant systems, including high patient numbers and a long follow-up time, are rare. This retrospective study evaluated the cumulative survival rate of a self-tapping, cylindrical implant system with a conical implant-abutment connection after 10 years of prosthetic loading., Materials and Methods: A total of 516 TiOblast implants (Astra Tech AB, Mölndal, Sweden) were placed in 108 patients. The patients were treated in the Department of Oral and Maxillofacial Surgery, Johannes Gutenberg University, Mainz, Germany, between September 1994 and May 2005. The main indications for implantation were the treatment of edentulous mandibles (74%) and partial edentulism (15%). Twenty-three implants were placed postradiation, and a further 64 implants were irradiated after insertion. In 153 implants, a bony augmentation was conducted prior to implantation., Results: The in situ rate was 89.7% after an average implantation time of 108 months. Eighty-three patients with 403 implants were available for investigation. Seventeen patients with 76 implants have died since 1994. Absence of osseointegration (n = 22), peri-implantitis (n = 18), fracture of the implants (n = 9), failing of primary stability (n = 2), and implants next to tumors (n = 2) were the reasons of explantation in 26 patients. Under analysis with different implant success-assessment criteria, the success rate showed results from 76 to 89%., Conclusion: With respect to the critical patient selection including a high number of patients with minor and major augmentations, the 10-year clinical use of the studied implant system showed acceptable results., (© 2010 Wiley Periodicals, Inc.)

The aim of this research was to explore the performance of a flapless surgical approach for immediate implant placement, simultaneous alveolar ridge augmentation, and immediate provisionalization in patients with complete loss of the facial bony lamella resulting from long-axis root fracture. Eighteen NobelPerfect implants were placed in 16 patients (follow-up, 13 to 36 months) who had sustained complete loss of the facial bony lamellae. Implants were inserted simultaneous to subperiostal bone augmentation with autogenous bone chips and underwent immediate provisionalization. Outcome variables included implant success, marginal bone levels, and pink esthetic score (PES). All implants achieved excellent primary stability. There were no implant losses. On average, interproximal marginal bone levels stabilized at 1.0 to 1.3 mm above the first thread. Postoperative cone beam computed tomography scans were available for 16 implant sites and confirmed restoration of the facial lamella in the vast majority of patients. Marginal esthetics, as assessed by the PES, was by and large preserved (mean postoperative PES, 12.5). Oral hygiene was highly predictive for the esthetic result. Survival rates, marginal bone levels, and esthetic results suggest a proof-of-principle for the new flapless immediate implant placement technique in patients with complete loss of the facial bony lamella. Oral hygiene status may be considered as a negative prognostic factor for the esthetic outcome.

Objective: This study is designed to assess dental implants supporting overdentures in edentulous patients with operated head and neck malignancies using parameters to detect peri-implant disease., Material and Methods: Thirty-four implants supporting overdentures in 34 oral cancer patients were examined. Clinical parameters [plaque index, probing depth, bleeding on probing (BOP), origin of peri-implant soft tissue, and amount of irradiation] were recorded, and microbiological identification of periodontal pathogens was carried out by DNA-DNA hybridization. To identify yeast species, the samples were cultivated on Sabouraud agar plates and subsequently identified by API 20C AUX plates. An implant site showing BOP, probing pocket depth (PPD)>or=5 mm and radiographic vertical bone loss was considered to have peri-implant disease., Results: Colonization by periodontal pathogens was found on 15 implants, while yeast species were found in 14 cases. Using a univariate analysis, none of the investigated parameters (microbiologic sign, detection of yeast, origin of peri-implant soft tissue and irradiation) were significantly correlated to signs of peri-implant disease. In the multivariate analysis, yeast [odds ratio (OR) 12.32, P=0.033] and periodontal pathogen (OR 9.88, P=0.046) were significant predictor variables for peri-implant disease. Yeasts were less frequently detected around implants placed in re-vascularized skin flaps if irradiation was set as a confounder (P=0.019)., Conclusions: With respect to the pilot study nature of the study peri-implant soft tissue origin and irradiation had little influence on the development of peri-implant disease. Yeast and periodontal pathogen were explanatory variables for the development of peri-implant disease. Considering the effect of irradiation on the prevalence of yeast, yeast was less frequently observed in peri-implant soft tissue of the skin. Based on these data, future studies on the role of yeast and soft tissue in peri-implant disease should be encouraged.

Purpose: This clinical report describes the use of implant-supported fixed dental prostheses (ISFDPs) in a severe case of dystrophic epidermolysis bullosa., Materials and Methods: The patient's appearance was characterized by reduced corporal growth and severe mutilation of the hands and feet. He was first examined at age 20. The severely decayed residual dentition had already been extracted by the time of examination. Conventional dentures were not possible due to severe microstomia and the fragility of the denture-bearing tissues. Even a modest manual touch was very painful and detached the epithelium of the oral mucosa. The first treatment was only possible under general anesthesia. To allow some prospect for oral rehabilitation, four implants were inserted in the maxilla and three in the mandible. Several years of steroid treatment had weakened the bony structures. Therefore, the diameter of the last drill used to prepare the bone for implant insertion was smaller than the diameter of the implants to improve primary stability. Complete FDPs with a shortened dental arch design served as superstructures. Several fractures in the screw-designed titanium abutments in the mandible necessitated insertion of three additional implants and an ISFDP with two occlusal units, which was screwed horizontally to a milled bar mesostructure., Results: Despite multiple fractures of the acrylic resin veneers caused by severe bruxism and the small occlusal surface, this rehabilitation proved successful until the patient died at age 25, as a consequence of his hereditary disease., Conclusion: This treatment greatly improved the patient's oral function, nutrition, and psychosocial well-being. Int J Prosthodont 2010;23:42-48.

This study examined the clinical performance of the scalloped NobelPerfect implant in a one-stage procedure (immediate provisionalization in the esthetic zone). In 20 patients, immediate prosthetic restorations were placed on 31 NobelPerfect implants and followed for up to 27 months. Outcome variables were success rates, marginal bone levels, and Pink Esthetic Score (PES) assessed per implant. One implant failed (success rate: 96.8%). Marginal bone levels averaged 1.7 mm above the first thread and remained stable during the observation period. Mean PES ratings were 11.3 (range, 8 to 14). Survival rates, marginal bone levels, and esthetic results suggest proof of principle for the preservation of the interproximal bony lamella with a scalloped implant design.

Purpose: The aim of this study was to compare insertion torque and resonance frequency analysis of different implant systems in an animal model with loaded implants., Materials and Methods: Three types of Brånemark implants (machined MkIII, TiUnite MkIII, and MkIV) and 2 types of Straumann implants (sandblasted, large-grit, acid-etched [SLA] and titanium plasma-sprayed [TPS]) were studied. Thirty-two implants of each type (n = 160) were placed in 16 beagle dogs. Maximum insertion torque values were recorded. After a healing period of 8 weeks, the implants were loaded for 3 months; the animals were then sacrificed. At placement, after healing, and at the end of the loading phase, resonance frequency analysis was performed and implant stability quotients (ISQs) were recorded., Results: Higher insertion torque values were seen for the conical MkIV than for the MkIII. No difference was seen between the Brånemark and Straumann implants on the basis of ISQ value at placement. ISQ and insertion torque values were lower for the cylindric Straumann implants than for the self-tapping implants. For all implant systems a significant decrease in median ISQ was observed, with a median decrease ranging from 3 to 6. ISQ values for self-tapping implants remained stable after loading, whereas the ISQ values for non-self-tapping cylinders decreased. The maximum insertion torque values for failed and successful implants were not significantly different. Significantly higher ISQ values at placement were seen for successful implants (P =.003). Based on this model for ISQ, a threshold of 65.5 was identified, with a sensitivity of 83% and specificity of 61% for prediction of implant loss. ISQ values at the start of loading were not predictive of implant loss in the loading period., Conclusion: Caution should be used when judging implant systems on the basis of resonance frequency analysis and torque measurement.