W. Peter Holbrook
University of Iceland
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Community Dentistry and Oral Epidemiology | 2010
Inga B. Árnadóttir; W. Peter Holbrook; Hafsteinn Eggertsson; Holmfridur Gudmundsdottir; Stefan Hrafn Jonsson; Jon Oskar Gudlaugsson; Sigurdur Runar Saemundsson; Sigfus Thor Eliasson; Helga Agustsdottir
OBJECTIVES To measure the prevalence of dental erosion in permanent teeth in Iceland as part of the National Oral Health Survey. METHODS A representative, nationwide sample of 2251 Icelandic children, 20% of those aged 6, 12 and 15 year, was examined. Dental erosion was recorded for all erupted permanent teeth and graded using the modified scale of Lussi. RESULTS Erosion was not seen in the permanent teeth of six-year-olds, but was present in 15.7% of 12-year-olds, more frequently in boys than girls (19.9% boys, 11.0% girls; P < 0.001). Among 15-year-olds, dental erosion was seen among 30.7% of subjects (38.3% boys, 22.7% girls; P < 0.001). Severity of erosion was mostly scored as grade I, with only 5.5% of 15-year-olds scored as grade II, mostly on tooth 46 (4.3%) and 36 (4.2%). For 12-year-olds, 0.9% had erosion scores of grade II mostly on tooth 46 (0.8%) and 36 (0.7%). No subjects had erosion of grade III. The most common clinical manifestation of erosion was the appearance of cup-like lesions on the cusps of lower first molars. CONCLUSIONS Dental erosion was frequently present by the age of 12; the prevalence doubled by age 15 and was seen almost twice as often among boys than girls. Teeth most frequently showing signs of erosion were the lower first molars. The rapidly growing prevalence of erosion demonstrated by this nationwide survey emphasizes the need for further research into the aetiology of erosion and possible methods of preventing and treating this emerging dental problem.
Community Dentistry and Oral Epidemiology | 2010
Helga Agustsdottir; Holmfridur Gudmundsdottir; Hafsteinn Eggertsson; Stefan Hrafn Jonsson; Jon Oskar Gudlaugsson; Sigurdur Runar Saemundsson; Sigfus Thor Eliasson; Inga B. Árnadóttir; W. Peter Holbrook
OBJECTIVES The Icelandic Oral Health Survey aimed to obtain new national data on the oral health of Icelandic children and teenagers. METHODS A representative stratified random cluster sample of 2251 Icelandic children in first, seventh and 10th grade, aged approximately 6-, 12- and 15-years old was examined for caries prevalence using the ICDAS criteria. Bite-wing digital radiographs were obtained for the children in 7th and 10th grade. RESULTS D(3)MFT scores by visual examination of 6-, 12- and 15-year olds were 0.12, 1.43 and 2.78 respectively but when including radiographs, the D(3)MFT rose to 2.11 at 12 years and 4.25 at 15 years. The Significant Caries Index, SiC, by visual examination for 12 and 15 y was 3.7 and 6.7 respectively but was 4.7 for 12 y and 8.9 for 15 y with radiographs. In all age groups and at most disease levels, caries was active in the majority of the lesions (58-100%). The percentage of children with no visually detectable caries at D(3)/D(1) level was 93%/74% for 6 years, 48%/22% for 12 years and 35%/16% for 15 years. When radiographs were included the percentage reduced to 34%/15% for 12 years and 20%/6% for 15 years. Approximately 80% of 12- and 15-year-olds had at least one of their first molars sealed, with the mean number of sealed first molars being 2.2 among 12 y and 2.0 among 15 y. CONCLUSIONS Caries levels were higher than expected in this national survey and further away from the goals of the National Health Plan for 2010 than anticipated. Caries distribution was skewed with more than half of the children having low caries scores but a wide distribution of caries experience was seen among the remaining population.
Acta Odontologica Scandinavica | 2004
Álfheiður Ástvaldsdóttir; W. Peter Holbrook; Sofia Tranæus
DIAGNOdent (KaVo, Biberach, Germany) has shown high diagnostic accuracy and intra‐operator agreement for caries detection, both in vitro and in vivo. The aims of this study were to compare DIAGNOdent with visual examination (VI) and bitewing radiographs (BW) for clinical assessment of occlusal fissures, and to evaluate inter‐device consistency of clinical recording using four different DIAGNOdent instruments; secondly, to correlate DIAGNOdent readings with microbial culture of the measured site. The subjects were young adults, the material comprising 34 occlusal fissures, scheduled for restorative treatment at the Dental School Clinic of the University of Iceland. Two examiners conducted visual and radiographic assessments. One examiner measured each site with four DIAGNOdent instruments in random order. The fissure was then opened and lesion depth was classified on a 4‐point scale. Bacterial samples were taken from the fissure before and after opening. Intra‐operator agreement was high (r = 0.85–0.98). Inter‐device correlation for the four DIAGNOdent instruments was significant in all cases (r = 0.81–0.92). However, a common cut‐off point could not be determined. There was weak but significant correlation between DIAGNOdent readings and all three classes of lesion depth. Level of infection showed very weak correlation with the DIAGNOdent readings. It was concluded that DIAGNOdent is more reliable in detecting dentinal caries if a proper cut‐off point is used than in indicating actual lesion depth. Readings from the different instruments were not directly comparable, however, owing to the lack of a common cut‐off point.
International Journal of Pharmaceutics | 1993
Stefán J. Sveinsson; W. Peter Holbrook
Abstract A co-polymer of methacrylic acid and methacrylic acid methyl ester (Eudispert) was used to formulate a mucoadhesive ointment. Liposomes containing triamcinolone acetonide were incorporated into (a) the Eudispert ointment, which contains 11% (w/w) of the neutralized polymet and 0.5% (w/w) gelatin, and (b) Orabase. The in vitro drug release and dissolution behaviour of these formulations were investigated. A clinical trial is currently being carried out and the initial findings indicate that the liposomal formulations are well tolerated and no local irritation has been observed.
British Dental Journal | 2003
W. Peter Holbrook; Inga B. Árnadóttir; Kay Ej
Non-carious destruction of teeth has been observed in archaeological material from various parts of the world and clearly pre-dates the first appearance of dental caries. Attrition, abrasion and erosion are also described in the classic text of Pindborg on the pathology of the dental hard tissues. Whilst the dental profession, at least in affluent parts of the world, was engaged in diagnosing, treating and later preventing dental caries these other causes of tooth destruction were largely ignored.
Clinical Oral Investigations | 2008
W. Peter Holbrook; Carolina Ganss
Quantifying tooth wear in general and erosion in particular mostly is made by distinguishing between lesions restricted to enamel and lesions reaching the underlying dentine. Various scores for grading have been used, but in all systems, higher scores are given in cases of exposed dentine, thus, indicating a more severe stage of the condition. Clinical diagnosis of exposed dentine is made by assessing changes in colour or optical properties of the hard tissues. This paper aims to review the literature and discuss critically problems arising form this approach. It appears that classifying the severity of erosion by the area or depth of exposed dentine is difficult and poorly reproducible, and taking into account the variation of enamel thickness, the amount of tissue lost often is not related simply to the area of exposed dentine. There has still been very little longitudinal investigation of the significance of exposed dentine as a prognostic indicator. Further work and discussion is needed to reevaluate the explanative power of current grading procedures.
Journal of Oral Pathology & Medicine | 2012
Skúli Skúlason; W. Peter Holbrook; Halldor Thormar; Gunnar B. Gunnarsson; Thórdís Kristmundsdóttir
BACKGROUND Current treatment of herpes labialis is usually with topical antiviral drugs and early drug administration is required for effectiveness. Monocaprin, a 1-monoglyceride of capric acid, has high microbicidal activity in vitro and efficiently inactivates herpes simplex virus. Tetracyclines are inhibitors of matrix metalloproteinases that are part of the inflammatory response and contribute to the breakdown of tissue in ulcers. The study objective was to investigate the antiviral and wound-healing effect of a hydrogel containing either monocaprin or a combination of monocaprin and a low dose of doxycycline in vivo against herpes labialis. METHODS Subjects were divided into two groups: (i) with prodromal symptoms of herpes labialis; (ii) with a vesicle. Both groups applied the hydrogel five times a day for five days. Test formulations were: (i) hydrogel containing monocaprin and doxycycline (MCD), (ii) hydrogel containing only monocaprin and (iii) placebo hydrogel. Formulations were distributed randomly to subjects within each group. Subjects recorded treatment results in a 6-day diary and a 7-day follow-up diary. RESULTS For the MCD group the mean time to healing was 5.5 days (prodromal) and 5.3 days (vesicles/ulceration) or significantly shorter than for the placebo groups (7.25 and 7.5 days respectively; P < 0.05). Pain relief was significantly more with MCD (combining both the prodromal and vesicle groups) than with the monocaprin and placebo groups (P = 0.0114). CONCLUSION Combining monocaprin with low-dose doxycycline offers an effective treatment for herpes labialiss, significantly reducing time to healing and pain compared with the placebo and monocaprin alone.
Acta Odontologica Scandinavica | 2010
Álfheiður Ástvaldsdóttir; Sofia Tranæus; Lena Karlsson; W. Peter Holbrook
Abstract Objective. Carious tissue fluoresces with a wavelength different from sound tissue when stimulated by light with a wavelength of 655 nm. This difference is thought to have a bacterial origin rather than indicating demineralization. This study aimed to measure fluorescence emitted by normal cultivable caries-associated bacterial flora and typical porphyrin-producing bacteria with DIAGNOdent, and to verify earlier findings that demineralization of the dental hard tissue does not affect DIAGNOdent readings. Material and methods. Bacterial samples were collected from five occlusal caries lesions in three subjects. From these, mixed anaerobic flora, Lactobacilli and mutans Streptococci were cultured in up to three different kinds of culture medium. Colonies of Lactobacilli and mutans Streptococci were also measured after transferring them to glass slides. Laboratory teaching strains of Prevotella spp., Porphyromonas gingivalis and Actinomyces odontolyticus were cultured anaerobically and fluorescence measured directly after an appropriate incubation period. Sound enamel surfaces of 15 extracted premolars were demineralized and changes in fluorescence measured. Results. DIAGNOdent readings > 20 were only obtained from young colonies of Prevotella and from colonies of mutans Streptococci cultured on mitis–salivarius–bacitracin agar. Higher measurements were obtained as the bacterial colonies aged. Lower measurements were obtained after transferring colonies to glass slides. Demineralization of enamel did not affect the DIAGNOdent measurements. Conclusions. The change in fluorescence measured with DIAGNOdent has a bacterial origin rather than occurring as a result of demineralization. The measurements are presumably dependent on bacterial metabolites rather than bacteria themselves, and probably record synergistic effects during the carious process rather than the quantity or species of bacteria involved.
Acta Odontologica Scandinavica | 2001
W. Peter Holbrook; Gunnlaugur Thor Gudmundsson; Kjartan Thor Ragnarsson
The purpose of this study was to review and analyze the records of herpes simplex infections from a specialist Oral Medicine clinic in Iceland, to investigate the clinical impression that the age of patients experiencing initial infection with this virus was higher than expected and that the character of the clinical picture of the disease had changed. Records of patients with herpes infections attending the Oral Medicine clinic covering a 3-year period were examined and the clinical and virological data analyzed. Diagnosis was based on clinical appearance, history, and viral identification with culture or detection of viral DNA by means of the polymerase chain reaction. Records of 60 patients (34 female) were included in the study (mean age, 23.1 years; range, 2-68 years). No patients were known or suspected to be positive for human immunodeficiency virus, none was known to be immunocompromised, and 38 patients (mean age, 16.6 years; 21 female) were diagnosed as having primary herpetic gingivostomatitis. Eighteen patients (mean age, 36.2 years; 11 female) had lesions of recurrent herpes simplex infection present on the oral mucosa. Primary infection with herpes simplex virus was more common in young adults than had been expected. Recurrent infections appeared on the oral mucosal even in otherwise healthy patients, and the clinical course of these infections in this age group sometimes followed a more severe course than that seen in young children.
Journal of Oral Microbiology | 2012
W. Peter Holbrook; Margrét O. Magnúsdóttir
Abstract Background: Dental caries has been strongly associated with mutans streptococci, particularly Streptococcus mutans and S. sobrinus. Many studies have linked these organisms to the carious process and counts of mutans streptococci have been used to monitor caries risk. The high levels of caries generally found in Iceland have enabled several studies to be performed on the variation within strains of S. mutans. Methods: This paper reports some studies showing phenotypic differences between strains of S. mutans that were related to whether the strain was isolated from an individual with active caries or from a caries-free subject. Results: Strains from individuals with active caries generally adhered better to apatite, were more vigorous in decalcifying apatite and had bacteriocin-like activity that was likely to help the strain compete successfully with other strains, for example in the dental plaque biofilm. Conclusions: Phenotypic differences exist between strains of S. mutans depending on the caries activity of the individual from whom the strain was isolated.