Immediate occlusal vs nonocclusal loading of implants: A randomized prospective clinical pilot study and patient centered outcome after 36 months.

BACKGROUND: Immediate provisionalization reduces chair time and improves patient comfort. PURPOSE: To analyze immediate functional loading vs nonfunctional loading with restorations in the posterior mandible for marginal bone defects, implant success/survival, and patient satisfaction. MATERIALS AND METHODS: A randomized controlled clinical trial was designed to assess these parameters based on 20 adult patients who underwent implant surgery, followed by immediate delivery of screw-retained or cemented single or splinted restorations in full occlusal contact or in infraocclusion (test and control group). A questionnaire with visual analog scales was used to assess patient satisfaction. RESULTS: Following 36-month data were evaluable for 9 patients (21 implants) in the study group (immediate functional loading) and for 10 patients (31 implants) in the control group (immediate nonfunctional loading). One implant in the control group was lost, hence the overall implant survival and success rate was 98.2%. Marginal bone defects were consistent with previous studies and comparable in both groups. Periotest values did not significantly change from baseline and the 12-month follow-up (Friedmann test). Patient satisfaction was high and did not involve any significant intergroup differences (Mann-Whitney U-test). CONCLUSIONS: Both types of immediate provisional restorations are viable in selected patients. Larger randomized controlled trials are needed to establish immediate functional loading as a standard treatment for partially edentulous jaws.

Immediate loading of four interforaminal implants supporting a locator-retained mandibular overdenture in the elderly. Results of a 3-year randomized, controlled, prospective clinical study.

BACKGROUND: Implant-retained overdentures have become a standard option for the prosthetic treatment of the edentulous mandible in the elderly. PURPOSE: This prospective study aimed to compare immediate and conventional loading of four interforaminal implants supporting a Locator-retained mandibular overdenture in elderly patients regarding implant survival, implant stability, and implant-related complications. MATERIAL AND METHODS: The study population comprised 20 completely edentulous patients (11 males) aged 60 years and older with severe mandible resorption. Each patient received four interforaminal implants (Neoss Ltd., Harrogate, UK). Following randomization, implants were loaded either immediately after dental implant surgery or 3 months after implant placement with the Locator-abutment system. At follow-up visits 3, 6 12, 24, and 36 months after loading, implant stability was evaluated with Periotest and Ostell. RESULTS: Twenty patients received 80 implants. In eight patients, 32 implants were loaded immediately. Two patients had to be switched from the immediate to the conventional loading group due to insufficient primary stability (≤30 Ncm). Implant survival was similar in both groups after 36 months. No implant was lost. Decreasing Periotest, and accordingly, increasing Ostell measurements indicated adequate osseointegration in both groups. The course of treatment was not significantly different in the two groups. There were comparable incidences of postoperative complaints like swelling, hematoma, or wound dehiscence, as well as need for prosthetic treatment due to abutment loosening or occlusal discrepancies. Incidence of pressure marks and number of patient visits were significantly higher in the conventional loading group. CONCLUSION: With sufficient primary stability, immediate loading of four interforaminal implants in the edentulous mandible might be the preferential choice in the elderly, reducing total treatment time, and number of patient visits.

Immediate Occlusal versus Non-Occlusal Loading of Implants: A Randomized Clinical Pilot Study.

BACKGROUND: Immediate occlusal and non-occlusal loading protocols have been discussed and, despite varying success rates, are considered viable in selected cases. Preoperative implant planning and intraoperative transfer are essential to the success of implant-supported reconstructions in partially or completely edentulous jaws. PURPOSE: This study was performed to compare clinical outcomes of immediate occlusal versus non-occlusal loading of posterior implants. MATERIALS AND METHODS: Of 19 patients with 52 screw-type implants replacing mandibular molars or premolars, nine patients with 21 implants were randomized to a study group that received immediate restorations with occlusal loading, whereas 10 patients with 31 implants were randomized to a control group that received provisional restorations without occlusal loading. Occlusal loading was defined as full loading in maximum intercuspidation. Single-tooth or splinted multiunit restorations were incorporated by screw retention or cementation. Marginal bone defects (MBD), implant survival, and implant success were evaluated 12 months after insertion. RESULTS: Both groups revealed similar MBD levels consistent with previous reports. No implants were lost (overall survival: 100%) or found to fail (overall success: 100%). No significant intergroup differences were noted for any of the evaluated parameters. CONCLUSIONS: Immediate restorations in partially edentulous mandibles demonstrated successful clinical and radiographic 12-month results. Larger long-term prospective studies are needed to confirm the final evidence and predictability of immediate functional loading as a standard treatment concept for partially edentulous jaws.

Three-dimensional accuracy of guided implant placement: indirect assessment of clinical outcomes.

PURPOSE: Precise preoperative implant planning and its exact intraoperative transfer are crucial for successful implant-supported rehabilitation of partially or completely edentulous patients. In the present pilot study, optical laser scanning was used to evaluate deviations between three-dimensional computer-assisted planned and actual implant positions by indirect methods. MATERIAL AND METHODS: Five patients receiving a total of 15 implants were included in this study. The used planning software was SimPlant 12.0 (Materialise Dental, Leuven, Belgium) to visualize the implant positions, and with an appropriate guided surgery protocol (Navigator™, Biomet 3i, Palm Beach Gardens, FL, USA) implant positions were implemented via tooth-supported stereolithografic surgical guides. All implants (Osseotite™, Biomet 3i) were inserted in a flapless approach and immediately provided with prefabricated temporary splinted restorations. Intraoral pickup impressions were taken postoperatively, and the implant positions of the master casts were compared with presurgical casts. Implant replica deviations were evaluated by three-dimensional optical laser scanning providing distances and angulations between implant replicas. RESULTS: Overall, the postsurgical implant replica positions were found to deviate from the positions in the preoperative cast by a mean of 0.46 ± 0.21 mm (range: 0.09-0.85 mm). Positional deviations were 0.27 ± 0.19 mm (range: 0.04-0.60 mm) along the x-axis representing the buccal-lingual directions, 0.15 ± 0.13 mm (range: 0.0-0.34 mm) along the y-axis representing the ventrodorsal direction, and 0.28 ± 0.19 mm (range: 0.02-0.59 mm) along the z-axis representing cranial and apical directions. Rotational deviations amounted to 14.04 ± 11.6° (range: 0.09-36.47°). CONCLUSIONS: The results of this pilot study demonstrate precise transfer of implant replica position by means of simulated guided implant insertion into a preoperative cast and a postoperative cast obtained from impressioning. Further studies are needed to identify appropriate evaluation techniques and mechanisms to increase the transfer precision of three-dimensional planning and guiding systems.

Soft tissue development around abutments with a circular macro-groove in healed sites of partially edentulous posterior maxillae and mandibles: a clinical pilot study.

OBJECTIVES: The aim of this study was to evaluate soft tissue development at concave circular macro-grooved titanium abutments in healed sites. MATERIAL AND METHODS: In a split-mouth pilot study 10 patients received two implants each at healed posterior sites in contralateral maxillary or mandibular jaw quadrants. Either circular macro-grooved concave study abutments or conventional convex control abutments were immediately provisionalized and received permanent crowns 3 months postimplantation. Marginal bone level, papilla index, modified plaque and bleeding index were recorded. The esthetic outcome was evaluated with standardized perpendicular pictures according to the Pink Esthetic Score (PES). Statistical analysis included the description of all variables by mean value, standard deviation and range. PES values were compared using the Wilcoxon signed rank test for paired data. RESULTS: Cumulative survival rate for all 20 implants was 100%. At the 1-year follow-up, there was no statistical significant difference of marginal bone levels between sites restored with the study (-0.11 ± 0.77 mm) vs. the control (-0.34 ± 0.53 mm) abutments (P>0.05). Esthetic evaluation (PES) revealed statistically significant differences in scores between the study group [study abutment group] (7.2 ± 2.82, 8 ± 1.89) and the control group [control abutment group] (9.5 ± 1.58, 10.5 ± 1.72) at the time of prosthetic delivery and the 1-year follow-up. Whereas PES scores for mesial papilla at control sites at the 1-year follow-up demonstrated statistically significant higher values, both soft tissue level and soft tissue contour at control sites revealed statistically significantly higher PES values (P<0.05) at time of prosthetic delivery and at 1-year follow-up when compared with study sites. CONCLUSIONS: Concave macro-grooved abutments in healed posterior maxillary and mandibular sites did not exhibit a superior soft tissue development compared with standard convex abutments.

Oral rehabilitation of adult twins with severe lack of bone due to hypohidrotic ectodermal dysplasia--a 12-month follow-up.

PURPOSE: Patients with x-linked hypohidrotic ectodermal dysplasia (XLHED, OMIM 305100) often present with exceptional oral conditions, because alveolar ridges can remain severely hypotrophic due to oligo- or anodontia in the primary and/or permanent dentition. This can seriously disable a young person physically and psychologically, and lead to sociopsychological isolation. PATIENTS AND METHODS: The oral rehabilitation of fraternal male twins with XLHED, one with severe hypodontia and the other with anodontia is described. The treatment of both patients comprised augmentation of the jaws using bicortical corticocancellous bone blocks from the medial aspect of the anterior hip, delayed implantation, and restoration of the occlusion with bar-retained overdentures. The multidisciplinary team approach included an oral and maxillofacial surgeon, a prosthodontist, and a speech therapist. RESULTS: After uneventful healing, the 12-month follow-up showed that sufficient osseointegration of the implants for optimized function was obtained by creating adequate de novo bone volume in the underdeveloped jaw regions. Full regular masticatory function was achieved, and esthetics were improved considerably in both patients. CONCLUSION: Augmentation and implant placement prior to prosthetic rehabilitation appears to be a suitable treatment option for adult patients with XLHED.

Harvesting of cancellous bone from the proximal tibia under local anesthesia: donor site morbidity and patient experience.

PURPOSE: The objective of this retrospective study was to evaluate postoperative morbidity, risk of complications, and patient discomfort after ambulatory tibial bone harvesting procedures under local anesthesia. PATIENTS AND METHODS: Between 2000 and 2005, bone was harvested from the head of the tibia for internal or external maxillary augmentation in 79 patients. A medial osteoplastic approach to the donor region was used. All patients' records were reviewed. Forty-five of the 79 patients later came in for follow-up examination. A traumatologist examined the donor region both clinically and radiologically. Subjective disorders and experiences of the patients were documented using a standardized questionnaire. RESULTS: The patient records revealed that 80% did not report significant complaints or gait disturbances after bone harvesting, and only 5% reported postoperative complaints or gait disturbances lasting longer than 2 weeks. In 1 case, a nondisplaced fracture healed without further complications. Clinical and radiologic examinations of 45 patients revealed full regeneration of the donor region in all cases. Some 91% of the patients described the outpatient bone harvesting procedure under local anesthesia as "not distressing" and would undergo such an intervention again if required. CONCLUSIONS: This study demonstrates that both complaints and risk of complications after outpatient bone harvesting from the proximal tibia under local anesthesia can be considered very low, especially as far as outpatient maxillary augmentation (eg, sinus floor elevation) is concerned.

In-patient comparison of immediately loaded and non-loaded implants within 6 months.

According to the Brånemark protocol, a stress-free healing period is one of the most emphasised requirements for implant integration. Recent studies have encouraged a progressive shortening of the healing period and immediate loading has been proposed for the edentulous mandible. This prospective study evaluated the clinical outcomes of 14 immediately loaded FRIALIT-2(R) implants compared with 28 non-loaded controls in an in-patient study. The results were based on clinical stability and on changes of bone level from implant placement to abutment connection 6 months after insertion. In the course of our investigation, seven patients with edentulous mandibles have been treated with 43 implants following an immediate-loading protocol. Six FRIALIT-2(R) implants were placed in the interforaminal region located at positions 34, 33, 32, 42, 43, 44. Bone level in relation to implant margin was measured and recorded. In order to obtain an in-patient comparison of immediately loaded and non-loaded implants, the ones at 33 and 43 were chosen to be immediately loaded by a Dolder-bar retained overdenture. The implants in position 32, 34, 42 and 44 were covered and left to heal. After a healing period of 6 months, second stage surgery was carried out. The clinical criteria to be checked at this point were survival, Periotest values and marginal bone level at the loaded and non-loaded implants. The mean Periotest value was -2.7 for the loaded and -5.6 for the non-loaded implants. The Mann-Whitney U-test showed that the difference was highly significant (P < 0.001). The mean bone level changes at prosthetic delivery were 0.9 mm resorption for the loaded implants and 0.33 mm for non-loaded implants. The difference was highly significant (P < 0.001). No implant failures were observed up to the prosthetic restoration 6 months post insertion. The results of this investigation allowed for direct comparison of implant survival and clinical results between immediately loaded implants and standard implants. Clinical bone changes at the 6-month evaluation demonstrated significantly higher crestal resorption around loaded implants. This fact was confirmed by higher median Periotest values (-3 vs. -6) of immediately loaded implants. According to the outcome of this study, immediate loading of two interforaminal implants with a Dolder-bar resulted in an intimate bone apposition comparable with implants with submerged healing. Nevertheless, the coronal bone level as well as clinical stability (PTV) were significantly lower in the case of the immediately loaded implants. Future studies will be necessary to evaluate marginal bone resorption, Periotest values and clinical success rates of mandibular immediately loaded implants in the long-term.

Immediate loading of single-tooth implants in the anterior maxilla. Preliminary results after one year.

According to the standard protocol, a load-free healing period is one of the most emphasized requirements for implant integration. Recent studies have encouraged a progressive shortening of the healing period for single-tooth implants and immediate loading has been proposed for the aesthetic zone in the maxilla. The present study evaluated clinical outcomes of immediately loaded FRIALIT-2 Synchro implants 12 months after placement in the maxillary incisal region. In the course of our investigation, nine patients have been treated following an immediate loading protocol. The stepped-screw type implants were inserted with an increasing torque up to 45 Ncm, thus measuring the primary stability of the implants. All implants were immediately restored with unsplinted acrylic resin provisional crowns and the patients provided with occlusal splints. Regular controls were performed at monthly intervals, intraoral radiographs were taken directly after implant placement, 6 and 12 months post insertion. The survival rate, clinical stability (Periotest) and radiographic coronal bone defects (CBD) were evaluated at delivery of the definitive superstructures (CBD 6) and 6 months later (CBD 12). Twelve FRIALIT-2 Synchro stepped screws of 3.8, 4.5 and 5.5 mm diameter and 13 and 15 mm length were placed in the incisal maxillary region. The median Periotest value 6 months post insertion was -2 with a minimum of -5 and a maximum of +2. The mean coronal bone level changes (CBD) at 6 and 12 months were 0.45 and 0.75 mm. No implant failed up to 12 months after insertion, resulting in a 100% survival rate. The presented results showed promising data for immediately loaded single-tooth implants in the anterior maxilla. Periotest values were within the range published for submerged implants. The radiographic coronal bone resorption after 6 and 12 months was even less than evaluated for implants placed in a standard two-stage procedure. It is evident that successful immediate loading protocols require a careful and strict patient selection aimed at achieving the best primary stability and avoiding any excessive functional or non-functional loading. Additional research needs to be done to provide data in situations where problems of poor bone quality, multiple implants or augmentation procedures must be overcome.

Evaluation of implants placed with barrier membranes. A restrospective follow-up study up to five years.

This follow-up study evaluated clinical and radiographic parameters of dental implants placed in combination with guided bone regeneration with barrier membranes. All implants functioned well up to 60 months after insertion. Forty-one patients, with a total of 72 augmented implants, who participated in a regular maintenance protocol, were investigated. Annual Periotest values (median value, - 3) revealed stable periimplant conditions and sustained osseointegration. At 6 months and annually thereafter up to five years, the radiographic evaluation yielded mean bone losses of 0.8, 1.25, 1.39, 1.42, 1.42 and 1.39 mm, respectively, with a range from 0 to 3.5 mm. No implant failures or losses were recorded. The results demonstrated stable periimplant conditions up to five years after membrane-protected osseous regeneration, with no significant differences in the radiographic bone level in regard to region, jaw or bone graft. Premature membrane exposure resulted in a significantly higher crestal bone loss up to 24 months. The newly formed bone appeared to be able to withstand functional loading for up to 60 months in a predictable manner.