Platelet-rich plasma application in sinus graft surgery: Part I--Background and processing techniques.

The uses of cytokine growth factors in soft tissue applications has been reported on. The scientific background and various processing techniques to prepare the autologous materials are reviewed here. An ongoing research project to study grafting of the maxillary sinus for bone regeneration and implant site preparation with the growth factor Platelet Rich Plasma is outlined.

Implant dentistry education for the practicing dentist.

Contemporary standards of care, as well as ethical and legal issues, dictate the incorporation of dental implants into the general dental practice. Given the simplicity of current implant systems, most general dentists already possess the clinical expertise necessary to provide basic implant restorative services to their patients. However, due to the restricted manner in which dental implant training was propagated in the United States, and perhaps due to its foreign origins, many competent dentists seem unaware of this greatly beneficial innovation. There are a variety of educational resources available for the uninitiated dentist to gain proficiency in basic implant dentistry. The ideal education in implant dentistry provides supervised hands-on clinical training on live patients as well as didactic instruction by recognized teachers in implant dentistry. Such education may or may not be devoid of commercial bias. This paper will describe many of these opportunities.

Maintaining and attenuating periodontal tissues for aesthetic implant placement.

Alveolar ridge resorption and soft tissue recession after tooth extraction inevitably disrupted the harmonious pre-existing periodontal complex, compromising clinicians' ability to recreate successful aesthetic restorations. Although numerous surgical procedures had been advocated for the augmentation of both the alveolar ridge and its soft tissue to ideal contours, questions remain regarding viability and predictability of these procedures. This is especially critical in the maxillary anterior region, where a the condition of the soft tissue complex and its relationship to the implant restoration and its adjacent dentition often determines the implant's success. The described technique of retaining the root remnant and inducing the proliferation of the surrounding tissue in conjunction with immediate implant placement results in the preservation of existing soft and hard tissue, thus minimizing the necessity of grafting procedures and facilitating primary flap closure during implant placement.

Scientific rationale for the surgical and prosthodontic protocol for immediately loaded root form implants in the completely edentulous patient.

This paper discusses a modified surgical and prosthodontic protocol to place implants in the completely edentulous patient. Methods for presurgical, prosthodontic workup, impression transfer technique, provisionalization, and attachment placement are also discussed.

Effects of smoking on implant success in grafted maxillary sinuses.

STATEMENT OF THE PROBLEM: Cigarette smoking has been identified as a significant risk factor for dental implant treatment. PURPOSE: This retrospective study evaluated the effect of smoking and the amount of cigarette consumption on the success rates of the implants placed in grafted maxillary sinuses. MATERIAL AND METHODS: Sixty patients (16 smokers and 44 nonsmokers) were evaluated for the effects of smoking on osseointegrated implants placed in 84 grafted maxillary sinuses that contained a total of 228 endosseous root-form implants. Seventy implants were placed in 26 maxillary sinuses in smokers, whereas 158 implants were placed in 58 sinuses in nonsmokers. The number of implant failures and the amount of cigarette consumption were recorded. RESULTS: Of the 228 implants, 205 (89.9%) remained in function, after a mean follow-up period of 41.6 months (2 to 60 months). There was a significantly higher cumulative implant success rate in nonsmokers (82.7%) than in smokers (65.3%) (P =.027). Overall cumulative implant success rate was 76%. There was no correlation between implant failures and the amount of cigarette consumption (P >.99). CONCLUSION: Within the limitations of this study, cigarette smoking appeared to be detrimental to the success of osseointegrated implants in grafted maxillary sinuses regardless of the amount of cigarette consumption.

Maxillary sinus augmentation prior to placement of endosseous implants: A histomorphometric analysis.

The aim of this prospective study was to histomorphometrically evaluate at various time intervals the mineralization stage and process of an allogeneic-xenogeneic bone graft used in sinus augmentation procedures. One biopsy was taken from 20 patients at either 6, 8, 10, or 12 months after sinus augmentation. Immediately following the biopsy, an endosseous implant was placed into the biopsy site. This protocol provided 4 groups of 5 patients each, based on healing time following sinus augmentation. Using backscattered electron image analysis, the specimens were histomorphometrically analyzed to determine the volume fractions of residual cancellous bone, newly formed bone, soft tissue, bovine hydroxyapatite, and "remineralized" freeze-dried demineralized bone allograft (rDFDBA). "Remineralization" of DFDBA particles was observed in a few areas in all specimens. Polarized light microscopy showed that only the 12-month biopsies had a predominance of lamellar bone formation. The area within the biopsies that represented the residual alveolar ridge consisted of 32.6% +/- 8.6% (mean +/- SD) of bone. In the grafted area of the biopsies the volume fraction of newly formed bone at 12 months (20.7% +/- 8.3%) was significantly higher (P < .05, analysis of variance) than at 6 months (8.1% +/- 3.0%). There was no statistically significant difference between newly formed bone in the inferior, central, and superior grafted areas in all 4 time intervals. This prospective study indicates that the mineralization process of an allogeneic-xenogeneic sinus graft is incomplete 6 months after the sinus augmentation procedure. New bone formation increased up to 12 months postaugmentation; however, it remained lower than the volume of residual bone.

Immediate loading of a single hydroxyapatite-coated threaded root form implant: a clinical report.

The successful results of endosseous root form implants in the treatment of partially and completely edentulous patients has been made possible by the application of standardized surgical and prosthetic protocols. Different techniques have been published in the literature with the purpose of reducing implant prosthetic rehabilitation times. This clinical case report describes a new surgical concept and a technique to fabricate screw-retained provisional crowns for immediate loading of free-standing single tooth implants. Further clinical and histologic studies are necessary in order to promote routine clinical application of this technique.

Mandibular fracture after endosseous implant placement in conjunction with inferior alveolar nerve transposition: a patient treatment report.

A patient with a severely atrophic right posterior mandible had three endosseous implants placed in conjunction with transposition of the inferior alveolar nerve. Three weeks following implant placement surgery, the patient experienced a spontaneous fracture of the mandible involving the two anterior implants. The two implants were removed, and the fracture was treated with open reduction and fixation with titanium mesh. The fracture healed, and the posterior implant integrated. This report suggests that the buccolingual and superior-inferior position of the mandibular canal can increase the possibility of mandibular fracture by increasing the size of the buccal cortical plate that is removed to expose the nerve during surgery.

Endosseous implant placement in conjunction with inferior alveolar nerve transposition: an evaluation of neurosensory disturbance.

This retrospective study evaluated neurosensory dysfunction and the implant success rate associated with 64 implants placed in 15 patients following transposition of the inferior alveolar nerve. A total of 21 inferior alveolar nerve mobilization surgeries were performed. The mean postoperative follow-up time was 41.3 months, with a range of 10 to 67 months. The effects of surgical technique and implant surface geometry on neurosensory dysfunction were evaluated by using light touch, brush stroke direction, and two-point discrimination. The implant success rate was 93.8% (60/64). The surgical technique that involved detaching the mental foramen resulted in a significantly greater incidence of neurosensory disturbance (77.8%, 7/9) than did the technique that left the bony foramen intact (33.3%, 4/12). The overall incidence of neurosensory disturbance was 52.4% (11/21).

Osseointegration: contemporary concepts and treatment.

The classical principles of osseointegration were based on a strict surgical protocol established through decades of experimental research and human clinical trials. These principles establish a sound scientific and clinical foundation for the neophyte implant surgeon. Research, however, is constantly accumulating, challenging a number of these original concepts and allowing deviation from the established protocol. It is anticipated that these changes will improve implant dentistry performance and expedite patient care. Sound clinical judgment based on experience and knowledge of the scientific literature must be exercised when deviations from the established protocol are considered.

Comparative three-dimensional analysis of two finite-element endosseous implant designs.

The finite-element method was used to assess force distribution to the cortical and cancellous bone surrounding two HA-coated, cylindrical implant designs, one grooved, the other smooth-sided. It was shown that, with both designs, large compressional stresses occurred in a small volume of bone at the coronal portion of the mandibular ridge. The stresses produced gave rise to a large stress gradient in the interface area. Significant differences were noted between the two designs in this area. It was also noted that the majority of the loading occurred in the cortical region of the mandibular ridge.

Eight-year clinical evaluation of HA-coated implants.

The safety and efficacy of HA-coated screw-type titanium dental implants was studied in an 8-year retrospective study. The results show that HA-coating clearly decreases failure rates in the posterior mandible and the anterior and posterior maxilla.

HA-coated implants: warranted or not?

Despite anecdotal reports that challenge hydroxyapatite (HA)-coated implant survivability, the experience in the placement of these implants over 9 years at Loma Linda University School of Dentistry has been favorable. The results of these implant placements are presented and analyzed in this article. After 7 years, the survival rate of HA-coated custom and stock blade-form implants is 97%. At 5 years, the survival rate for all upper HA-coated root form implants is 98%, and for all HA-coated implants placed in the lower jaw it is 99%. For implants placed in maxillary type 4 bone, there was a 32.6% failure rate among uncoated implants, but a rate of 14.9% in HA-coated implants. The causes of implant failure are often related to factors other than the type of implant, such as iatrogenic factors and poor oral hygiene.

Root-form implants placed in subantral grafted sites.

Life-table analysis of survival data of implants placed in subantral grafts reveals a high rate of survival, particularly in comparison with implants placed in non-grafted subantral sites. However, sample size (158 grafted, 140 non-grafted, in a total of 120 patients) and follow-up time remain insufficient to reach a definite conclusion. Results also appear improved over other reports in which the sinus was penetrated by the implants, possibly because the procedure has become more standard over the years.

Solving the problem of violated intermaxillary space caused by poor pre-planning and improper placement of endosseous implants: a case report.

Every dental implant patient needs thorough evaluation and pre-surgical planning. It is imperative for the practitioner to have absolute knowledge of the implant system to be used. Nevertheless, sometimes we find ourselves in very difficult, almost unrestorable, situations. Often, we cannot rely on the implant manufacturers, and we have to be ready to customize some parts in order to solve difficult clinical situations. This case report shows how customized magnet keepers were fabricated by use of plastic IME's as casting patterns in order to solve the problem of violated intermaxillary space.

Sinus lift grafts and endosseous implants. Treatment of the atrophic posterior maxilla.

Patients from multicenters were treated with sinus lift graft operations and placement of implants. Surgical procedures healed uneventfully with minimum pain, swelling, or morbidity. Grafts healed with few complications or failures. Implants placed into the grafts support prosthetic reconstruction and are predictable over time. The question of what graft material to use is discussed. Grafts of non-resorbable HA (Interpore 200), bovine cortical HA (Bio-Oss), resorbable HA (OsteoGen), and freeze-dried demineralized bone powder and granules are presented. Results of biopsy, histometry, backscattered electron microscopy, cell labeling, and special stain suggest consistent bone growth into a variety of graft materials. In the authors' opinion investigation must continue to 1. Determine the healing time for different graft materials. At present, anecdotal evidence suggests that sinus grafts of autogenous bone heal for 4 to 6 months; freeze-dried demineralized bone heals for 12 to 16 months; and alloplastic materials with freeze-dried demineralized bone heal for 9 to 11 months. 2. Evaluate histologic evidence of bone growth into different bone replacement graft materials. 3. Evaluate the long-term follow-up and success of implants placed within sinus grafts. 4. Determine the remodeling potential of different hard tissue graft materials under implant functional loads.

The histologic evaluation of the implant interface with heterograft and allograft materials--an eight-month autopsy report, Part II.

This paper presents post mortem histologic specimens of the implant/osseous tissue interface from a patient who had had simultaneous bilateral maxillary sinus augmentation and root-form implant placement eight months prior. Two implants were observed: One implant was totally submerged in bone and graft material (2E), and other implant (3E) was devoid of bone at the apex. Microscopic examination revealed that a bony interface existed around implant 2E but that implant 3E had minimal bony interface. It is suggested that the minimal bony interface was the result of minor implant movement induced by variations in barometric pressure on the apex of implant 3E, and that eight months would not have been enough healing time prior to loading for this patient.