• Accuracy of bone mapping and guided flapless implant placement in human cadavers using a model-based planning procedure.

      Fitzgerald, Maurice; O'Sullivan, Michael; O'Connell, Brian; Houston, Frank; Division of Restorative Dentistry and Periodontology, Dublin Dental School and Hospital, Trinity College, Dublin, Ireland. (2010-09)
      The use of the model-based NobelGuide encourages adherence to the restorative-driven approach. The accuracy of the method is within acceptable limits for guided surgery described in the literature, and the use of the bone mapping is satisfactory in cases with adequate bone volume. The technique can also be used in sites with insufficient bone volume, but a mucoperiosteal flap procedure is recommended. Int J Oral Maxillofac Implants 2010;25:999-1006.
    • A comparison of implant-retained mandibular overdentures and conventional dentures on quality of life in edentulous patients: a randomized, prospective, within-subject controlled clinical trial.

      Harris, David; Höfer, Stefan; O'Boyle, Ciaran A; Sheridan, Sean; Marley, John; Benington, Ian C; Clifford, Tom; Houston, Frank; O'Connell, Brian; Dublin Dental School & Hospital, Trinity College, Dublin, Ireland. david@drdavidharris.com (Clinical oral implants research, 2013-01)
      To determine any difference in patient response to implant overdentures compared with conventional complete dentures alone.
    • Demographics of implant placement and complications of a patient subgroup in a dental hospital population.

      Brennan, Maire; Houston, Frank; O'Sullivan, Michael; O'Connell, Brian; Department of Restorative Dentistry, University Dental School and Hospital, Wilton, Cork. (2011-03-14)
      Implant-supported overdentures and fixed prostheses were both clinically successful. However, patients and clinicians should be aware that soft tissue and mechanical complications are common.
    • Detection of staphylococcal cassette chromosome mec type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes in human clinical isolates of clonal complex 130 methicillin-resistant Staphylococcus aureus.

      Shore, Anna C; Deasy, Emily C; Slickers, Peter; Brennan, Grainne; O'Connell, Brian; Monecke, Stefan; Ehricht, Ralf; Coleman, David C; Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland. (2011-08)
      Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec (SCCmec) elements. In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. The isolates were identified as methicillin-susceptible S. aureus using the GeneXpert real-time PCR assay. Whole-genome sequencing of one isolate (M10/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ-mecA-mecR1-mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). The SCCmec element was almost identical to that of SCCmec type XI (SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The open reading frames (ORFs) identified within SCCmec XI of M10/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. A third DR was identified ca. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. aureus strains were predominantly from bovine sources. The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon.
    • Emergence of hospital- and community-associated panton-valentine leukocidin-positive methicillin-resistant Staphylococcus aureus genotype ST772-MRSA-V in Ireland and detailed investigation of an ST772-MRSA-V cluster in a neonatal intensive care unit.

      Brennan, Gráinne I; Shore, Anna C; Corcoran, Suzanne; Tecklenborg, Sarah; Coleman, David C; O'Connell, Brian; National MRSA Reference Laboratory, St. James’s Hospital, Dublin, Ireland. gbrennan@stjames.ie (2012-03)
      Sequence type 22 (ST22) methicillin-resistant Staphylococcus aureus (MRSA) harboring staphylococcal cassette chromosome mec (SCCmec) IV (ST22-MRSA-IV) has predominated in Irish hospitals since the late 1990s. Six distinct clones of community-associated MRSA (CA-MRSA) have also been identified in Ireland. A new strain of CA-MRSA, ST772-MRSA-V, has recently emerged and become widespread in India and has spread into hospitals. In the present study, highly similar MRSA isolates were recovered from seven colonized neonates in a neonatal intensive care unit (NICU) in a maternity hospital in Ireland during 2010 and 2011, two colonized NICU staff, one of their colonized children, and a NICU environmental site. The isolates exhibited multiantibiotic resistance, spa type t657, and were assigned to ST772-MRSA-V by DNA microarray profiling. All isolates encoded resistance to macrolides [msr(A) and mpb(BM)] and aminoglycosides (aacA-aphD and aphA3) and harbored the Panton-Valentine leukocidin toxin genes (lukF-PV and lukS-PV), enterotoxin genes (sea, sec, sel, and egc), and one of the immune evasion complex genes (scn). One of the NICU staff colonized by ST772-MRSA-V was identified as the probable index case, based on recent travel to India. Seven additional hospital and CA-ST772-MRSA-V isolates recovered from skin and soft tissue infections in Ireland between 2009 and 2011 exhibiting highly similar phenotypic and genotypic characteristics to the NICU isolates were also identified. The clinical details of four of these patients revealed connections with India through ethnic background or travel. Our study indicates that hospital-acquired and CA-ST772-MRSA-V is currently emerging in Ireland and may have been imported from India on several occasions.
    • Patient satisfaction and oral health-related quality of life outcomes of implant overdentures and fixed complete dentures.

      Brennan, Maire; Houston, Frank; O'Sullivan, Michael; O'Connell, Brian; Division of Restorative Dentistry and Periodontology, Dublin Dental School and Hospital, Trinity College, Dublin, Ireland. (2010-07)
      Among all patients who had similar numbers of implants placed, those who received an implant overdenture were less satisfied and had lower OHQOL than the patients who had a fixed prosthesis. Since patient and dentist preferences influenced the type of prosthesis provided, it is likely that subjective, patient-related factors are major determinants of satisfaction and treatment outcomes.
    • A radiographic analysis of implant component misfit.

      Sharkey, Seamus; Kelly, Alan; Houston, Frank; O'Sullivan, Michael; Quinn, Frank; O'Connell, Brian; Division of Restorative Dentistry and Periodontology, Dublin Dental School and Hospital, Trinity College, Dublin, Ireland. (2011-07)
      Radiographs are commonly used to assess the fit of implant components, but there is no clear agreement on the amount of misfit that can be detected by this method. This study investigated the effect of gap size and the relative angle at which a radiograph was taken on the detection of component misfit. Different types of implant connections (internal or external) and radiographic modalities (film or digital) were assessed.
    • Tooth agenesis in patients referred to an Irish tertiary care clinic for the developmental dental disorders.

      Hashem, Atef A; O'Connell, Brian; Nunn, June; O'Connell, Anne; Garvey, Therese; O'Sullivan, Michael; Division of Restorative Dentistry & Periodontology, Dublin Dental School & Hospital, Lincoln Place, Dublin 2. (2010)
      PURPOSE: This study was carried out to determine the prevalence, severity and pattern of hypodontia in Irish patients referred to a tertiary care clinic for developmental dental disorders. MATERIALS AND METHODS: Details of 168 patients with hypodontia referred during the period 2002-2006 were entered in a database designed as a national record. Tooth charting was completed using clinical and radiographic examinations. The age of patients ranged from 7-50 years, with a median age of 20 years (Mean: 21.79; SD: 8.005). RESULTS: Hypodontia referrals constituted 65.5% of the total referrals. Females were more commonly affected than males with a ratio of 1.3:1. The number of referrals reflected the population density in this area; the majority were referrals from the public dental service. Mandibular second premolars were the most commonly missing teeth, followed by maxillary second premolars and maxillary lateral incisors; maxillary central incisors were the least affected. Symmetry of tooth agenesis between the right and left sides was an evident feature. Slightly more teeth were missing on the left side (n = 725) than on the right side (n = 706) and in the maxillary arch (n = 768) as compared to the mandibular arch (n = 663). Some 54% of patients had severe hypodontia with more than six teeth missing; 32% had moderate hypodontia, with four to six teeth missing. The most common pattern of tooth agenesis was four missing teeth. CONCLUSION: Hypodontia was a common presentation in a population referred to this tertiary care clinic. The pattern and distribution of tooth agenesis in Irish patients appears to follow the patterns reported in the literature.
    • Tooth agenesis in patients referred to an Irish tertiary care clinic for the developmental dental disorders.

      Hashem, Atef A; O'Connell, Brian; Nunn, June; O'Connell, Anne; Garvey, Therese; O'Sullivan, Michael; Division of Restorative Dentistry & Periodontology, Dublin Dental School & Hospital, Lincoln Place, Dublin 2. (Irish Dental Association, 2010-02)
      This study was carried out to determine the prevalence, severity and pattern of hypodontia in Irish patients referred to a tertiary care clinic for developmental dental disorders.