Antimicrobial and immunomodulatory properties of PGLa-AM1, CPF-AM1, and magainin-AM1: Potent activity against oral pathogens

Cationic amphipathic α-helical peptides are intensively studied classes of host defence peptides (HDPs). Three peptides, peptide glycine-leucine-amide (PGLa-AM1), caerulein-precursor fragment (CPF-AM1) and magainin-AM1, originally isolated from norepinephrine-stimulated skin secretions of the African volcano frog Xenopus amieti (Pipidae), were studied for their antimicrobial and immunomodulatory activities against oral and respiratory pathogens. Minimal effective concentrations (MECs), determined by radial diffusion assay, were generally lower than minimal inhibitory concentrations (MICs) determined by microbroth dilution. PGLa-AM1 and CPF-AM1 were particularly active against Streptococcus mutans and all three peptides were effective against Fusobacterium nucleatum, whereas Enterococcus faecalis and Candida albicans proved to be relatively resistant micro-organisms. A type strain of Pseudomonas aeruginosa was shown to be more susceptible than the clinical isolate studied. PGLa-AM1 displayed the greatest propensity to bind lipopolysaccharide (LPS) from Escherichia coli, P. aeruginosa and Porphyromonas gingivalis. All three peptides showed less binding to P. gingivalis LPS than to LPS from the other species studied. Oral fibroblast viability was unaffected by 50. μM peptide treatments. Production of the pro-inflammatory cytokine IL-8 by oral fibroblasts was significantly increased following treatment with 1 or 10. μM magainin-AM1 but not following treatment with PGLa-AM1 or CPF-AM1. In conclusion, as well as possessing potent antimicrobial actions, the X. amieti peptides bound to LPS from three human pathogens and had no effect on oral fibroblast viability. CPF-AM1 and PGLa-AM1 show promise as templates for the design of novel analogues for the treatment of oral and dental diseases associated with bacteria or fungi.

Subjective impact of minimally invasive dentistry in the oral health of older patients

OBJECTIVES: The aim of this study was to investigate if a minimally invasive oral health package with the use of atraumatic restorative treatment (ART) or a conventional restorative technique (CT) would result in any perceived benefit from the patients' perspective and if there would be any difference between the two treatment groups.

MATERIALS AND METHODS: In this randomised clinical trial, 99 independently living older adults (65-90 years) with carious lesions were randomly allocated to receive either ART or conventional restorations using minimally invasive/intervention dentistry (MID) principles. Patients completed an Oral Health Impact Profile (OHIP)-14 questionnaire before and 2 months after treatment. They were also asked to complete a global transition question about their oral health after treatment.

RESULTS: At baseline, the mean OHIP-14 scores recorded were 7.34 (ART) and 7.44 (CT). Two months after treatment intervention, 90 patients answered the OHIP-14 and the mean scores were 7.23 (not significant (n.s.)) and 10.38 (n.s.) for the ART and CT groups, respectively. Overall, 75.5 % of patients stated that their oral health was better compared to the beginning of treatment.

CONCLUSIONS: Although not shown by the OHIP-14, patients perceived an improvement in their overall oral status after treatment, as demonstrated by the global transition ratings in both groups.

CLINICAL RELEVANCE: Dental treatment using minimally invasive techniques might be a good alternative to treat older individuals, and it can improve their oral health both objectively and subjectively.

The impact of rehabilitation using removable partial dentures and functionally orientated treatment on oral health-related quality of life: a randomised controlled clinical trial

OBJECTIVES: This study aimed to compare two different tooth replacement strategies for partially dentate older patients; namely functionally orientated treatment according to the principles of the shortened dental arch (SDA) and conventional treatment using removable partial dentures (RPDs) using a randomised controlled clinical trial. The primary outcome measure for this study was impact on oral health-related quality of life (OHRQoL) measured using the short form of the oral health impact profile (OHIP-14).

METHODS: Patients aged 65 years and older were randomly allocated to two different treatment groups: the RPD group and the SDA group. For the RPD group each patient was restored to complete arches with cobalt-chromium RPDs used to replace missing teeth. For the SDA group, patients were restored to a premolar occlusion of 10 occluding pairs of natural and replacement teeth using resin bonded bridgework (RBB). OHRQoL was measured using the OHIP-14 questionnaire administered at baseline, 1 month, 6 months and 12 months after treatment intervention.

RESULTS: In total, 89 patients completed the RCT: 44 from the RPD group and 45 from the SDA group. Analysis using a mixed model of covariance (ANCOVA) illustrated that treatment according to the SDA concept resulted in significantly better mean OHIP-14 scores compared with RPD treatment (p<0.05). This result was replicated in both treatment centres used in the study.

CONCLUSIONS: In terms of impact on OHRQoL, treatment based on the SDA concept achieved significantly better results than that based on RPDs 12 months after treatment intervention (trial registration no. ISRCTN26302774).

CLINICAL SIGNIFICANCE: Functionally orientated treatment delivery resulted in significantly better outcomes compared to removable dentures in terms of impact on OHRQoL.

Age-related oral changes

Age-related oral changes are seen in the oral hard and soft tissues as well as in bone, the temporomandibular joints and the oral mucosa. As older patients retain their natural teeth for longer, the clinical picture consists of normal physiological age changes in combination with pathological and iatrogenic effects.

CLINICAL RELEVANCE: With an ageing population retaining more of its natural teeth for longer, dental professionals should expect to observe oral age changes more frequently.

The importance of oral health for the systemic well being of an ageing population

The proportion of adults over the age of 60 years is expanding rapidly across European Union countries, including the Republic of Ireland. As the older population has grown faster than the total population, the proportion of older persons relative to the rest of the population has increased considerably (Figure 1). This trend mirrors the arrival of the “baby boomer� generation into early old age and will have wide ranging effects on social, political and economic spheres as well as presenting significant challenges for healthcare delivery and public healthcare policy.

Survey of oral health behaviours of patients receiving methadone therapy at a drug rehabilitation centre

Background: This survey aimed to record the dietary habits and oral health behaviours of patients undergoing methadone maintenance therapy at a Scottish drug rehabilitation centre.The objectives were to obtain descriptive data for each of the participants on items including dietary habits, oral hygiene practices and dental health. The study also aimed to explore explanatory relationships between dietary habits, oral hygiene practices and dental health (DMFT) in methadone users.
Methods: A cross – sectional descriptive study using survey methodology was conducted of consecutive adult patients undergoing methadone maintenance therapy at a non-residential drug rehabilitation centre in Dundee, Scotland. A self-completion retrospective questionnaire was distributed to 66 consecutive patients.
Results: A response rate of 74.2% was achieved. Participants reported low daily intakes of fresh fruit and vegetables with diets high in fatty foods. Respondents reported regular snacking between meals and consumption of large amounts of sugared carbonated drinks. Oral hygiene practices were poorly adhered to and a high level of dental disease was observed amongst participants. Poisson regression analysis revealed that the amount of alcohol consumed per day (p=0.02), the length of time taking methadone (p=0.002) the amount of sugar added to hot drinks (p<0.0001) and regular dental attendance (p=0.0001) were all independently associated with poor dental health.
Conclusions: Dietary habits and adherence to oral hygiene practices amongst this group of patients were very poor. This study suggests that these behaviours were contributing to the high levels of dental disease observed in this group.