Biomedical subjects

Patrick J Henry

Publications and source records attributed to Patrick J Henry.

6 recordsLinked to original sources

PubMed2007

Inflammation associated with implants with different surface types.

OBJECTIVES: The aim of this study was to determine the nature of the inflammatory infiltrate associated with different transmucosal implant surfaces in dogs. METHODS: Three experimental and one control single-stage implants were randomly placed on each side of the jaw in eight dogs. The transmucosal portion of the test implants consisted of an acid-etched surface (type A), a machined surface with a circumferential groove (type C) and a surface prepared by mild anodic oxidation (type D). The control was a standard machined surface (type B). In order to determine the response to the different surfaces, plaque control was carried out twice weekly following placement of the implants for the entire period of the experiment. At 6 months, gingival biopsies and plaque samples were obtained. The area of inflammatory infiltrate and the nature of the infiltrating cell types were determined using immunohistology. Real-time polymerase chain reaction was used to identify putative periodontal pathogens. RESULTS: Inflammatory infiltrates were associated with all implant surfaces and were commonly found subepithelially and perivascularly. T cells were the predominant infiltrating cell type in all lesions, associated with the different surfaces. In all lesions the CD4 : CD8 ratio was approximately 2 : 1. Statistical analysis showed that the type C surface (machined surface with a groove) had significantly larger inflammatory infiltrates than the type B surface (machined surface without a groove; P<0.05). No statistically significant differences were found with respect to the size of the inflammatory infiltrates or in terms of the nature of infiltrating cells. However, despite the intensive plaque control regime, plaque was present on all implant surfaces at the time of biopsy 6 months after placement. All implants had similar numbers of Tannerella forsythia, Fusobacterium nucleatum and Porphyromonas gingivalis. Actinobacillus actinomycetemcomitans, was not detected in any sample. CONCLUSIONS: These results suggest that the development of inflammation associated with implants is independent of surface type, but is nevertheless associated with the presence of plaque. The different surfaces had no influence on the nature of the infiltrate, with T cells being the predominant cell type in all lesions. Finally, the different implant surface types seemed not to influence the peri-implant microbiota. However, the presence of the circumferential groove tended to be associated with larger infiltrates. Whether this is due to increased plaque accumulation remains to be determined.

Acid Etching, Dental↗

PubMed2004

A clinical evaluation of the Zygoma fixture: one year of follow-up at 16 clinics.

PURPOSE: To evaluate treatment outcome with Zygoma fixtures (Nobel Biocare, Göteborg, Sweden) with regard to fixture survival, patient satisfaction, and function of prosthesis replacement. MATERIALS AND METHODS: The treatment outcome of 76 patients treated with 145 Zygoma fixtures at 16 centers was evaluated. Patient's and dentist's evaluations of the functional and aesthetic outcome of the treatment were assessed at delivery of prosthesis and at the 1-year follow-up visit. At the 1-year follow-up visit, the status of the peri-implant mucosa around the abutments and the amount of plaque were registered. RESULTS: Sixty-six of the 76 patients, with 124 Zygoma fixtures supporting the prosthetic restorations, were evaluated at the 1-year follow-up. The overall survival rate for the Zygoma fixtures was 97.9% after 1-year of follow-up. Eighty percent of the patients were fully satisfied with both aesthetic and functional outcome at the time of prosthetic insertion and at the 1-year follow-up. All reported data from the dentists, with the exception of one restoration with several abutment screw loosenings, scored from acceptable to excellent for the aesthetic and functional outcome of the treatment. The status of peri-implant mucosa was recorded as normal in approximately 60% of the sites. Plaque, when present, was more often detected on the palatal surfaces compared with the buccal surfaces. CONCLUSION: This 1-year follow-up of Zygoma fixtures has shown good results with an acceptable number of minor complications and a majority of satisfied patients.

Adult↗

PubMed2003

Prospective multicenter study on immediate rehabilitation of edentulous lower jaws according to the Brånemark Novum protocol.

BACKGROUND: During recent years a new treatment concept, Brånemark Novum, has been developed in which implants are inserted in the edentulous lower jaw and immediately connected to a prefabricated titanium bar. A fixed prosthesis is then attached to the bar during or immediately following surgery. PURPOSE: The aim of the present study was to investigate the application of this concept under various settings, to determine technique sensitivity, and to evaluate the clinical outcome after 1 year of follow-up. MATERIALS AND METHODS: Fifty-one patients were included in a prospective multicenter investigation and followed up for 1 year. Cumulative implant survival rates were evaluated by life table analysis. In addition, clinical comparisons were performed to evaluate implant loss in relation to patient characteristics. Questionnaires were used to evaluate the treatment protocols and to obtain patients' opinions. RESULTS: The prosthetic treatment was completed on the same or the following day in 76% of the patients. The cumulative implant survival rates for implants and prostheses were 91% and 94%, respectively, after 12 months. CONCLUSIONS: The present study demonstrated that single-stage surgery and immediate loading of implants with prefabricated bridgework in the mandible can result in high implant success and significant reduction in treatment time, with patient satisfaction.

Adult↗

PubMed2002

Do interleukin-1 polymorphisms predict the development of periodontitis or the success of dental implants?

Factors which increase the risk of severe adult periodontitis (AP) may also contribute to the success of dental implants. To determine which cytokines may be relevant, levels of interleukin-1alpha (IL-1alpha), interleukin-1beta (IL-1beta), interleukin-1 receptor antagonist (IL-1ra), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) mRNA were quantitated in gingival tissue from periodontitis patients and healthy controls. Periodontitis significantly increased levels of IL-1alpha, IL-1beta, IL-6 and IFN-gamma mRNA relative to healthy tissues. IL-1 was selected for further study, as it has inflammatory and bone resorbing properties. We examined IL-1A(-889) and IL-1B(+3953) alleles in Caucasian patients with AP and early-onset periodontitis (EOP), patients with dental implants and healthy individuals. The IL-1B(+3953) polymorphism was associated with AP. This was evident from an increased homozygosity for allele 2 in patients with AP and a decreased heterozygosity in advanced AP patients. IL-1A(-889) and a composite genotype [IL-1A(-889)2 plus IL-1B(+3953)2] showed no association with the incidence of periodontitis, disease onset or disease severity. IL-1A(-889), IL-1B(+3953) and the composite genotype also showed no association with failure of dental implants.

Adult↗

PubMed2002

A review of guidelines for implant rehabilitation of the edentulous maxilla.

This review suggests some guidelines and protocols for treatment of the edentulous maxilla with osseointegrated implants. Evidence-based treatment options are discussed with reference to risk assessment. Developing technologies applicable to diagnosis, clinical procedures, and laboratory techniques are also discussed. Osseointegrated implants are increasingly advocated as a treatment option for maxillary edentulism and in many situations are the treatment of choice.

Clinical Protocols↗

PubMedDate not supplied

Oral implant restoration for enhanced oral function.

1. The present paper reviews the clinical applications of implant-anchored restorations replacing teeth and defects of the craniofacial skeleton resultant from congenital, traumatic and surgical tissue loss. 2. Different categories of tooth and tissue loss were treated in controlled multicentre prospective clinical trials. More recent developments have been the subject of limited pilot studies. 3. Long-term results and meta-analysis reviews have shown that osseointegrated implant-supported restorations were at least equal to, and in some applications superior to, traditional treatment methods. 4. Based on the outcome of a 30 year research and development programme and validation in numerous clinical trials, osseointegrated implant dental rehabilitation has become a viable treatment alternative for missing teeth and, for some applications, is considered to be a standard of care.

Clinical Trials as Topic↗