Biomedical subjects

Frank P Strietzel

Publications and source records attributed to Frank P Strietzel.

3 recordsLinked to original sources

PubMed2006

Healing pattern of bone defects covered by different membrane types--a histologic study in the porcine mandible.

Few investigations on guided bone regeneration (GBR) focus on the behaviour of tissues adjacent to barrier membranes. This study was conducted to (1) evaluate the barrier function potential of different resorbable and nonresorbable membranes for GBR, (2) investigate their structural changes after different intervals, and (3) characterize tissue composition and reaction adjacent to the barrier by qualitative histologic evaluation. Seven barriers for GBR were used per animal (made of dense or expanded polytetrafluoroethylene (d/ePTFE), titanium, polyetherurethane, collagen and two polylactide-polyglycolide-/-trimethylenecarbonate-co-polymers (PLPG, LPGTC) in standardized defects not exceeding the critical size) without using bone substitution material or autogenous bone at the right inferior margin of the mandibles of six domestic pigs. Samples of the defect areas with membranes were harvested after 2 days (one animal), 4 and 8 (two animals, each) and 12 weeks (one animal), respectively. The healing of bone defects was completed in all animals after 12 weeks. Nonresorbable barriers prevented the soft tissue in-growth into standardized defects. Thinner layers of fibrous tissue were seen underneath the dense and rigid barriers (dPTFE, titanium) when compared with collagen and PLPG/LPGTC, in which soft-tissue plugs occupied the crestal defect portion. PLPG-/LPGTC-barriers underwent structural changes after 4 weeks and revealed blistered central layers, whereas structural changes were not evident in nonresorbable barriers. The degradation of PLPG-/LPGTC-membranes was present with in-growth of fibres, vessels, and cells. Using collagen or synthetic polymer barriers for GBR, the application of bone or bone substitutes to prevent membrane prolapse into the defect is suggested.

Animals↗

PubMedDate not supplied

Tissue-engineered bone for lateral alveolar ridge augmentation: a case report.

Bone matrix derived from mandibular periosteal cells and cultivated by tissue engineering on a polymer fleece has recently been used for sinus floor elevation and augmentation. This case report focuses on clinical and histologic results after lateral ridge augmentation of a localized non-space maintaining defect in the right posterior area of the mandible using tissue-engineered bone. Implant supported prosthetic rehabilitation of a partially edentulous 32-year-old woman was planned involving a fixed partial denture. Preoperative investigations revealed a transversely reduced alveolar ridge width on the right side of the posterior mandible. Lateral augmentation was performed using tissue-engineered bone obtained by autogenous periosteum cells from the same area. Six months after augmentation 2 implants were placed and a bone biopsy was obtained from the augmented area. Transverse ridge dimensions were found to be enhanced. Histologic examination of the biopsy revealed dense lamellar bone. Wound healing was uneventful after all surgical interventions. This case report demonstrates the successful clinical application of tissue-engineered bone for lateral augmentation of the transversely reduced alveolar ridge. The results suggest that periosteum-derived tissue-engineered bone can be used to create a sufficient implant site not only for the sinus floor elevation and augmentation procedure for vertical bone enhancement but also for lateral augmentation.

Adult↗

PubMedDate not supplied

Implant-prosthetic treatment in HIV-infected patients receiving highly active antiretroviral therapy: report of cases.

PURPOSE: Since 1997, the use of highly active antiretroviral therapy (HAART) has significantly improved systemic health and life expectancy of patients who test positive for the human immunodeficiency virus (HIV) in industrialized countries. Therefore, although implant-supported prosthetic rehabilitation has been restricted to immunocompetent individuals, it may be considered for these patients. CASE REPORTS: The treatment course of implant-prosthetic rehabilitation in 3 patients is reported. Patient 1 (male, age 64 years) was under 4-drug therapy; patient 2 (male, age 38 years) and patient 3 (female, age 49 years) were under 3-drug therapy. Two patients had suffered from AIDS-defining diseases prior to HAART. Oral manifestations of HIV infection were not diagnosed throughout the observation period. Patients had CD4+ cell counts between 250 and 800/mL, and viral load was below 50/mL. Perioperative antibiotic treatment was not applied. Two patients presented with edentulous mandibles. In the third patient, single-tooth replacement of both mandibular first molars was performed. A total of 10 Frialit-2 implants were placed without augmentation procedures. RESULTS: One implant failed after 3 months and was successfully replaced. Two patients received magnet-retained overdentures in the mandible, and 1 patient was treated with single crowns. All implants and restorations are successfully in function. Neither radiographic nor clinical signs of inflammation were detected during the observation period (range, 7 to 32 months). CONCLUSIONS: The outcomes of the 3 patients suggest that immunologically stable HIV-positive patients on HAART may be considered for implant-prosthetic rehabilitation.

Adult↗