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J Dermody

Publications and source records attributed to J Dermody.

6 recordsLinked to original sources

Why endodontic retreatment is less successful than primary root canal therapy.

Endodontic retreatment has been proven less effective than conventional root treatment. Factors dictating this include difficulty in accessing the root canal system in retreatment cases, problems in negotiating a highly resistant micro flora and unfavourable anatomy. Patients should, therefore, be counselled on the possibility of failure necessitating surgical procedures and possibly extraction. However, despite these mitigating factors success is still a realistic goal in the majority of cases.

Dental Restoration Failure↗

Prevalence of CTLA-4 polymorphism A49G in Ashkenazi Jews.

Type 1 diabetes has been associated with numerous genetic loci. One locus, IDD12, includes the gene for cytotoxic T lymphocyte antigen (CTLA-4). A polymorphism at position 49 in the CTLA-4 gene, causing a substitution of Thr --> Ala, has been associated with various autoimmune diseases, including diabetes. The frequency of the polymorphism in European and Oriental populations has been recorded, but the frequency among different ethnic groups within the United States has yet to be established. In the present study, we analyzed 100 DNA samples from Ashkenazi Jews to determine the polymorphism's prevalence in that population. The A/A genotype was found in 49% of individuals, 41% were heterozygous A/G, and 10% possessed the G/G genotype. The prevalence of the A/A genotype in Ashkenazi Jewish population is the highest reported to date. The incidence of the homozygous G/G genotype within Spanish controls, 8.8%, is the lowest, followed by the Ashkenazi general population. The frequency of the non-diabetes-associated A/A genotype shows a similarity to the frequency of the diabetes-susceptible HLA haplotype, DR4-DQ8. The low prevalence of the autoimmune-associated G allele among Ashkenazi Jewish and Spanish populations may explain a lower than expected incidence of diabetes in HLA-susceptible populations.

Abatacept↗

Histological evaluation of repair using a bioresorbable membrane beneath a resin-modified glass ionomer after mechanical furcation perforation in dogs' teeth.

Resorbable barriers have been shown both clinically and histologically to produce favorable periodontal regenerative outcomes. The purpose of the present study was to evaluate the histological response to one such resorbable barrier (Atrisorb) when used as a matrix under a resin-modified glass ionomer (RMGI) sealant in the repair of furcation perforations in experimental animals. After anesthesia, pulp extirpation and filling of radicular canals with zinc oxide-eugenol cement, furcal perforations were made in 30 lower premolar (P2, P3, and P4) teeth of labrador dogs with a 1 mm diameter round bur in a conventional handpiece. The perforated teeth were randomly divided into two groups of 15 teeth. Group 1 teeth were treated with RMGI alone and group 2 with the resorbable barrier under RMGI. Six teeth without perforations served as negative controls. Pulp chambers of all teeth were filled with RMGI cement. Animals were sacrificed after 3 months. The teeth and the surrounding structures were processed for light microscopy. There were no differences found between results for glass ionomer alone and barrier with glass ionomer. The conclusion of this study is that placement of a resorbable barrier at the pulp chamber aspect of a furcation perforation did not result in superior healing, compared with the use of resin-modified glass ionomer alone.

Absorbable Implants↗

Inherited thrombophilia genes in minorities.

Mutations in several genes have recently been identified which predispose to thrombosis, specifically Factor V G1691A (Factor V Leiden), Prothrombin G20210A, and Methylene tetrahydrofolate reductase (MTHFR) C677T. The prevalence of these genes in European populations has been studied, but there is little data on their prevalence in minorities. Samples from a predominantly African-American population were analyzed for these mutations. While the G20210A mutation in the prothrombin gene and homozygosity for the C677T mutation of the MTHFR were not found in African-Americans, it appears that the carrier rate for the MTHFR C677T among Hispanics may be higher than in other reported groups.

Asian People↗

Learning a clinical method to identify a mandibular reference position.

The teaching of clinical maxillomandibular relationships is an area of weakness in dental school curricula. Most difficulties arise when a reference position is required to adjust or reconstitute the maximum intercuspation of the dentition. The dentist-derived concept of the centric maxillomandibular relation position is used to solve this problem. There is no consensus on the definition of this term. In the descriptions of clinical technique for recording the centric maxillomandibular relation position, clinical criteria to judge whether or not the position required has been achieved usually are not given. The dorsal border paths of the envelope of movement were used to develop a clinical criterion to identify the centric maxillomandibular relation position. Force or "guidance" is not used in this method. Test-patients with normal masticatory systems were randomly selected and fitted with a mechanical tracking apparatus. 50 undergraduate dental students and dental nurses were randomly selected and given instruction in the clinical technique to identify the centric maxillomandibular relation position. The ability of these students to identify the reference position was assessed by having them perform the technique blindfolded on the test-patients on whom tracking apparatus was fitted. Sixty eight percent of the test-clinicians succeeded in using the method to identify the reference position. There was no significant difference in the abilities of subgroups to use the method successfully, e.g., women compared to men, 2nd year students to 3rd year students. It was concluded that the method was a satisfactory way of learning how to identify the centric maxillomandibular relation position in a gentle, non-invasive fashion.

Curriculum↗