bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of refractive state ratios and the onset of myopia
Authors: Lin J. T.
Published: December 2005

Purpose:  To develop formulae for the refractive state ratios, axial length growth and the age of onset (A*) of myopia. Calculated results are compared with measurements.

Methods:  Using an image equation, the axial length in the ametropic state (L) is related to the length in the emmetropic state (L*) and refractive error (D) by a rate of change M (D mm−1). Three refractive state ratios are defined: C1 = L/r1, C2 = L/L* and C3 = L/H, where r1 and H are the anterior surface radius of the cornea and the transverse dimension of the eye, respectively. The age of onset A* is calculated by the rate of change of refractive error (M) and the axial growth rates N and N* in the ametropic and emmetropic states, respectively.

Results:  The three ratios C1, C2 and C3 are increasing function of the myopia power, for example, C1 = 3.4, 3.1, 2.9 for D = −8, 0, +4 dioptres, respectively. The calculated C1* (for the emmetropic state) varies between 3.08 and 3.14, depending on corneal shape, and C3 = 0.985, 1.0, 1.04 for D = +3, 0, −3 dioptres: these values are consistent with measured data. For a typical system with effective focal length F = 22.25 mm, L* = 24.2 mm and L = 23.4, 24.9, 25.9 mm for D = +2, −2, −5 dioptres, respectively. The calculated rates of change of refractive error M = 2.3–2.9 D mm−1 for F = 22–23 mm are also consistent with measured values 2.4–2.7 D mm−1. The age of onset A* is calculated to be proportional to 1/(M dN), where dN = N−N* is the axial growth rate difference between the ametropic and emmetropic states and may be used as a better predictor for myopia onset than the conventional ratio L/r1. The A* is given by the crossing of L and L* curves, in which myopia onset occurs earlier for larger M dN.

Conclusion:  The theory provides formulae to calculate various refractive state ratios, which are consistent with measurements. By defining two rate functions, M and N, the onset of myopia can be predicted.
Development of a technique for recording the focal rod ERG
Authors: Binns Alison , Margrain Tom H.
Published: December 2005

The scotopic ERG recorded in response to a focal stimulus has a double b‐wave. The first wave results from direct focal stimulation of the retina, and the second originates in the peripheral retina in response to scattered light. The aim of this study was to assess two possible protocols for the isolation of the focal rod response, namely ‘Subtraction’ and ‘Background Adaptation’ techniques. The Subtraction technique involved the recording of a full‐field response, which matched the b‐wave elicited by intraocular light scatter, and the subtraction of this full‐field response from the initial trace to isolate the focal component. In the Background Adaptation technique an adapting surround was used to suppress the response from the peripheral retina. Focal rod responses were isolated with both techniques. However, the Background Adaptation technique was found to more reliably elicit a focal response with a measurable a‐wave, and was also considerably less time consuming than the Subtraction technique.
Iris melanoma: a case report and review
Authors: Millodot Michel , Hendler Karen , Pe'er Jacob
Published: December 2005

Iris melanoma is a rare ocular tumour, which can be detected early in its development. This tumour is almost always unilateral and arises usually from a pre‐existing naevus. Failure to detect it may be associated with morbid ocular and systemic complications, yet there are successful therapies to treat this condition, if detected early. The patient presented to the eye clinic with symptoms of occasional, brief loss of vision in his left eye for a few weeks prior to his visit. Slit‐lamp examination revealed a mass on the inferior part of the iris of the left eye. Intra‐ocular pressure measurements were RE 15 mmHg and LE 38 mmHg. It was found that a tumour had spread throughout the iris stroma and invaded the anterior chamber angle. Although enucleation would have been the treatment of choice in the past, the trend today in the treatment of a growing, large circumscribed iris tumour is to excise it. It was successfully excised by irido‐cyclo‐trabeculectomy.
Managing ‘suspicious glaucomatous discs’ identified during digital‐photography‐based diabetic retinopathy screening
Authors: Steele C. , Steel D. , Bone H. , McParland L. , Green L. , Fraser S.
Published: December 2005

Purpose:  An audit to demonstrate the outcome of patients identified with suspicious glaucomatous discs within a digital‐photography‐based diabetic retinopathy screening programme.

Methods:  Primary care based digital photographic screening was performed utilising mydriasis and two‐field digital photography for all patients with diabetes. Patients identified with discs suspicious of glaucomatous optic neuropathy (GON) were initially referred to an accredited community‐based optometrist for further assessment. Some patients were then referred to secondary care where appropriate.

Results:  From 1st April 2002 to 31st March 2003 a total of 3868 patients were screened for diabetic retinopathy. This audit revealed that 55 subjects were identified by retinal screeners as having discs suspicious of glaucoma. A total of 29 were already under glaucoma clinic review. A total of 23/26 remaining were referred for an assessment by an accredited optometrist. Of these 13 were normal, 6 were referred to secondary care and 4 failed to attend. The three remaining were referred directly to secondary care.

Conclusions:  All nine referrals to secondary care were deemed appropriate by a glaucoma specialist. This suggests that the system described does not lead to over‐referral of suspicious discs – although the issue of how many glaucomatous discs are missed during screening (false negatives) will only be answered in the longer term.
Indicators for sustainable energy development: Brazil's case study
Authors: Schaeffer Roberto , Szklo Alexandre Salem , Cima Fernando Monteiro , Machado Giovani
Published: December 2005

This article summarizes the results of the project on indicators for sustainable energy development (ISED) in Brazil. The project's aim was to present energy related economic, social and environmental data to policy makers in a coherent and consistent form, showing interlinkages, time‐series and cross‐sectoral analyses and assess energy policy. Two priority areas assessed by these indicators, regarding the country's energy supply and demand, helped in the identification of a number of energy policy options that focused on specific aspects of the country's energy sector. On the supply side, these options include the development and stimulation of renewable energy, such as small‐scale hydroelectric, wind, solar photovoltaic power and bagasse cogeneration; stimulation of programmes for ethanol use as automotive fuel and sugarcane bagasse cogeneration; and implementation of natural gas‐fired, combined heat and power (CHP) plants. On the demand side, policy options include: the full implementation of the law on efficiency standards for appliances; expansion of utility investment in end‐use energy efficiency; adoption of targets and protocols to reduce energy intensity in the industrial sector; improvement of passenger transport efficiency; and the creation of a fund to improve energy affordability for the poor.
Indicators for sustainable energy development in Thailand
Authors: Todoc Jessie L. , Todoc Monaliza J. , Lefevre Thierry
Published: December 2005

This article examines energy priorities for Thailand from the economic, social and environmental perspectives of sustainable development. The article uses a set of indicators devised by the International Atomic Energy Agency in partnership with other international agencies and research institutes in seven countries. Thailand's energy efficiency in the 1980s and 1990s are analysed using energy intensity indicators, and possible impacts on sustainable energy development are highlighted. The early 1990s in particular was an important period for Thailand, as the country was at the height of its economic growth, and a number of energy efficiency and conservation programmes were launched. Energy intensity indicators show continuing and faster growth in energy consumption relative to economic activity. The financial crisis in the late 1990s did halt growth in energy consumption, with positive consequences on environmental emissions, but only temporarily as Thailand's economy quickly started to recover in 2000. Notwithstanding the financial crisis, the other indicators show significant progress in economic and social dimensions.
Energy and environment in the European Union: An indicator‐based analysis
Authors: Taylor Peter G. , Wiesenthal Tobias , Mourelatou Aphrodite
Published: December 2005

The European Environment Agency (EEA) is the European Union body dedicated to providing sound, independent information on the environment. It is a major information source for those involved in developing, adopting, implementing and evaluating environmental policy in Europe, and also for the general public. In line with its mandate, the EEA has developed — focused around a set of policy relevant questions — a set of indicators to assess progress in Europe in integrating environmental considerations into the energy sector. Each question is answered through one or more indicators describing the development of the sector in Europe, implications for the environment and links to policy actions. The indicators cover not only the current situation, but also trends and prospects and, most importantly, point to the conditions for change that are needed for progress towards a more sustainable energy policy that benefits the environment. The results of the most recent assessment are presented in this article and show that in many areas of environmental integration there have been some successes, but overall progress to date has been insufficient. Substantial additional action will therefore be required in the future if the European Union is going to move towards a more environmentally sustainable energy system.
EU sustainable development indicators: An overview
Authors: Ledoux Laure , Mertens Roeland , Wolff Pascal
Published: December 2005

The European Union's commitment to sustainable development at the 1992 Earth Summit resulted in an EU‐wide sustainable development strategy, adopted in Gothenburg in 2001. This article presents an overview of the set of sustainable development indicators (SDIs) recently adopted by the European Commission to monitor, assess and revise the strategy. It provides a critical assessment of the current status of the indicator set, and reviews the main policy trends in the areas of the strategy through a brief analysis of headline indicators, placing energy and climate change issues in a broader perspective. Finally, the article compares the energy SDIs to the recent inter‐agency energy indicators for sustainable development (EISD), underlining their similarities as well as their different priorities and objectives. The article concludes that further research is needed to improve the SDI set and further explore the linkages between themes.
Gaps and Mismatches between Global Conservation Priorities and Spending
Authors: HALPERN BENJAMIN S. , PYKE CHRISTOPHER R. , FOX HELEN E. , CHRIS HANEY J. , SCHLAEPFER MARTIN A. , ZARADIC PATRICIA
Published: December 2005

Abstract: Several international conservation organizations have recently produced global priority maps to guide conservation activities and spending in their own and other conservation organizations. Surprisingly, it is not possible to directly evaluate the relationship between priorities and spending within a given organization because none of the organizations with global priority models tracks how they spend their money relative to their priorities. We were able, however, to evaluate the spending patterns of five other large biodiversity conservation organizations without their own published global priority models and investigate the potential influence of priority models on this spending. On average, countries with priority areas received greater conservation investment; global prioritization systems, however, explained between only 2 and 32% of the US$1.5 billion spent in 2002, depending on whether the United States was removed from analyses and whether conservation spending was adjusted by the per capita gross domestic product within each country. We also found little overlap in the spending patterns of the five conservation organizations evaluated, suggesting that informal coordination or segregation of effort may be occurring. Our results also highlight a number of potential gaps and mismatches in how limited conservation funds are spent and provide the first audit of global conservation spending patterns. More explicit presentation of conservation priorities by organizations currently without priority models and better tracking of spending by those with published priorities are clearly needed to help make future conservation activities as efficient as possible.
Effects of Introduced Salmonids on a Montane Population of Iberian Frogs
Authors: BOSCH JAIME , RINCÓN PEDRO A. , BOYERO LUZ , MARTÍNEZ‐SOLANO IÑIGO
Published: December 2005

Abstract:  Amphibians are declining worldwide because of multiple factors, including human‐mediated introduction of fishes into naturally fishless areas. Although several studies have focused on the effect of exotic fishes on native amphibians breeding in ponds or lakes, little is known about their effects on stream‐breeding species. We studied the effects of introductions of native brown trout (Salmo trutta) and exotic brook trout (Salvelinus fontinalis) on the stream‐breeding, endemic Iberian frog ( Rana iberica) in a protected area in central Spain. We assessed occurrence patterns of tadpoles and salmonids and compared habitat use of the three species. We also determined experimentally whether chemical cues from salmonids elicited antipredator behavior in tadpoles. Finally, we assessed the relative influence of tadpole habitat preferences, differences in salmonid species, and invasion geography on tadpole occurrence. Despite widely overlapping habitat preferences, tadpoles and trout did not coexist, with the former restricted to fishless habitats. Tadpoles detected chemical cues from both trout species and reacted by decreasing their activity, although the response toward the native brown trout was stronger. The residual distribution of Iberian frogs in Peñalara is better explained by the geography of fish invasions than by the fish species involved. Measures such as fish extirpation from certain areas, aimed at recovering lost habitat and improving connectivity among remaining populations of Iberian frogs, seem critical for the species' long‐term survival in central Spain.
The Interplay between Climate Variability and Density Dependence in the Population Viability of Chinook Salmon
Authors: ZABEL RICHARD W. , SCHEUERELL MARK D. , McCLURE MICHELLE M. , WILLIAMS JOHN G.
Published: December 2005

Abstract: The viability of populations is influenced by driving forces such as density dependence and climate variability, but most population viability analyses (PVAs) ignore these factors because of data limitations. Additionally, simplified PVAs produce limited measures of population viability such as annual population growth rate (λ) or extinction risk. Here we developed a “mechanistic” PVA of threatened Chinook salmon (Oncorhynchus tshawytscha) in which, based on 40 years of detailed data, we related freshwater recruitment of juveniles to density of spawners, and third‐year survival in the ocean to monthly indices of broad‐scale ocean and climate conditions. Including climate variability in the model produced important effects: estimated population viability was very sensitive to assumptions of future climate conditions and the autocorrelation contained in the climate signal increased mean population abundance while increasing probability of quasi extinction. Because of the presence of density dependence in the model, however, we could not distinguish among alternative climate scenarios through mean λ values, emphasizing the importance of considering multiple measures to elucidate population viability. Our sensitivity analyses demonstrated that the importance of particular parameters varied across models and depended on which viability measure was the response variable. The density‐dependent parameter associated with freshwater recruitment was consistently the most important, regardless of viability measure, suggesting that increasing juvenile carrying capacity is important for recovery.
Estimation of Mechanical Heart Valve Cavitation in an Electro‐hydraulic Total Artificial Heart
Authors: Lee Hwansung , Taenaka Yoshiyuki , Kitamura Soichro
Published: December 2005

Abstract:  The purpose of this study was to establish a method for estimating mechanical in vitro heart valve cavitation in an electro‐hydraulic total artificial heart (EHTAH). The variations in the left driving pressure (LDP) slope of the EHTAH were used as an index of the cavitation intensity. The LDP slope was controlled by changing the stroke volume of the EHTAH. The stroke volume was changed from full‐filling and full‐eject to partial‐filling and partial‐eject conditions. A 25‐mm Medtronic Hall valve was installed in the mitral position of the EHTAH. Cavitation bubbles were concentrated on the valve stop; the major cause of these cavitation bubbles was determined to be squeeze flow. The valve‐closing velocity was found to be proportional to increases in the LDP slope and the stroke volume of the left blood pump. The cavitation intensity and the cavitation event rate increased with increases in the stroke volume of the EHTAH. A consistent correlation was observed between the valve‐closing velocity and the cavitation intensity. The LDP slope of the EHTAH may play an important role in estimating the mechanical heart valve cavitation intensity.
Is Skeletal Muscle Ventricle Chronic Stability Dependent on Wall Stress? Design Implications
Authors: Gustafson Kenneth J. , Sweeney James D. , Gibney John , Fiebig‐Mathine Lee Ann
Published: December 2005

Abstract:  Chronic skeletal muscle ventricle (SMV) stability is essential for clinical implementation. SMVs in animal models have chronically expanded or collapsed when exposed to physiologic pressures. SMV wall stress is a more appropriate indicator than pressure or geometry to compare SMVs between studies. SMV wall tensions during conditioning were determined for SMVs that collapsed, expanded, or were isovolumetric in a previous study. Wall stresses in SMVs that expanded (2.76 ± 0.803 N/cm2) were significantly greater than isovolumetric SMVs (0.89 ± 0.450) and SMVs that collapsed (0.88 ± 0.451). These data support the existence of minimum and maximum wall stresses for SMV volume stability and provide empiric estimates for SMV design. Scaling SMV designs from animal models with smaller volumes and similar pressures may result in greater wall stresses in clinical designs. Therefore, the use of volume limiting implants or an isovolumetric conditioning phase to increase the wall stress expansion threshold may be required.
Evaluation of Biodegradable Polyesters Modified by Type II Collagen and Arg‐Gly‐Asp as Tissue Engineering Scaffolding Materials for Cartilage Regeneration
Authors: Hsu Shan‐hui , Chang Shih‐Hau , Yen Hung‐Jen , Whu Shu Wen , Tsai Ching‐Lin , Chen David Chanhen
Published: December 2005

Abstract:  Synthetic biodegradable polyesters poly(l‐lactide) (PLLA) and poly(d,l‐lactide‐coglycolide) (PLGA) (50:50) modified by porcine type II collagen and an Arg‐Gly‐Asp (RGD)‐containing protein were evaluated as scaffolds for cartilage regeneration in this study. Cytocompatibility of the polymer films was tested using immortalized chondrocytes. Neocartilage formation in vitro on cell‐seeded scaffolds was further examined using primary porcine chondrocytes. The inflammatory response of the scaffolds was evaluated subcutaneously in rats. A pilot animal study was conducted, in which rabbit allogeneic chondrocyte‐seeded scaffolds were implanted to repair the defected rabbit knee cartilage. The results demonstrated that PLGA as well as its blends with PLLA had better cell growth than pure PLLA, and that type II collagen enhanced, but RGD inhibited cell proliferation. Scaffolds made of blended PLLA/PLGA had larger dynamic compressive modulus compared to scaffolds made of PLLA or PLGA single polymer. Chondrocyte‐seeded scaffolds modified by type II collagen without RGD had the greater number of cells as well as higher glycosaminoglycan (GAG) and collagen contents compared to scaffolds without type II collagen modification or scaffolds further modified with RDG. Type II collagen modification prevented infiltration by host tissue and capsule formation. Unmodified PLLA and PLLA/PLGA constructs demonstrated persisting inflammatory response after 6 months, while all type II collagen‐modified PLLA/PLGA constructs showed complete repair and no inflammation. Partial or full repair was observed after 2 months of postimplantation in type II collagen‐modified PLLA/PLGA constructs, with equal cellularity and 75–80% matrix contents of a normal rabbit articular cartilage. It was concluded that PLLA/PLGA blended scaffolds modified by type II collagen were a potential tissue engineering scaffold for cartilage regeneration.
Improvement of Metabolic and Cardiorespiratory Responses Through Treadmill Gait Training With Neuromuscular Electrical Stimulation in Quadriplegic Subjects
Authors: De Carvalho Daniela Cristina Leite , Martins Cristiane Luzia , Cardoso Simone David , Cliquet Alberto
Published: December 2005

Abstract:  This work assessed the influence of treadmill gait training with neuromuscular electrical stimulation (NMES) on the metabolic and cardiorespiratory responses in quadriplegic subjects. The gait group (GG) (n = 11) performed 6 months of treadmill training with 30–50% body weight support and with the help of physiotherapists, twice a week, allotting 20 min for each session. The control group (CG) (n = 10), during the 6 months of training, did not perform any activity using NMES, performing instead conventional physiotherapy. Metabolic and cardiorespiratory responses (O2 uptake [VO2], CO2 production [VCO2], pulmonary ventilation (VE), heart rate [HR], and blood pressure [BP]) were measured on inclusion and after 6 months. For the GG, differences were found in all parameters after training (P < 0.05), except for HR and diastolic BP. During gait, VO2 (L/min) increased by 36%, VCO2 (L/min) increased by 42.97%, VE (L/min) increased by 30.48%, and systolic BP (mm Hg) increased by 4.8%. For the CG, only VO2 and VCO2 (L/min) significantly increased at rest (30.82 and 16.39%, respectively) and during knee‐extension exercise (26.29 and 17.37%, respectively). Treadmill gait with NMES was, therefore, more efficient toward increasing the aerobic capacity due to yielding higher metabolic and cardiovascular stresses.
Continuous Venovenous Renal Replacement Therapy With a Pulsatile Tubular Blood Pump: Analysis of Efficacy Parameters
Authors: López‐Herce Jesús , Rupérez Marta , Sánchez César , García Cristina , García Elena , Rodríguez Daniel , Del Cañizo Juan F.
Published: December 2005

Abstract:  A three‐valve pulsatile tubular pump was used in 10 pigs weighing 9.9 ± 0.3 kg, connected to a neonatal hemofiltration (HF) circuit to analyze the parameters to determine the ultrafiltration effectiveness for venovenous continuous renal replacement therapy. Forty 30‐min periods were studied to analyze the influence of the catheter diameter, purification technique (HF or hemodiafiltration), pump pulsation frequency, percentage time in diastole, percentage time in diastole in which the postpump valve was closed, and percentage time in systole in which the postfilter valve was closed, on ultrafiltrate volume and blood flow through the filter. A higher ultrafiltrate flow was achieved with a frequency of 60 bpm than with 30 bpm, a diastolic time of 65% of the total cycle versus 50%, and a blood flow of greater than 20 mL/min versus less than 20 mL/min. The ultrafiltrate flow increases in relation to the blood flow, the frequency of the pump, and the diastolic time.
Is paternal postpartum depression associated with maternal postpartum depression? Population‐based study in Brazil
Authors: Pinheiro R. T. , Magalhães P. V. S. , Horta B. L. , Pinheiro K. A. T. , da Silva R. A. , Pinto R. H.
Published: December 2005

Objective:  To describe the prevalence of paternal postpartum depression (PPD) as well as its association with maternal PPD.

Method:  A population‐based random sample of 386 couples was assessed from the sixth to the 12th week postpartum for demographic characteristics, alcohol misuse (AUDIT) and depressive symptoms [Beck Depression Inventory (BDI)]. Logistic regression was employed to control for potential confounders.

Results:  In the BDI, 26.3% of mothers and 11.9% of fathers scored above the selected threshold of 10. Mild maternal depression [odds ratio (OR) 3.31, 95% CI 1.52–7.20] and moderate to severe maternal depression (OR 8.44, 95% CI 3.53–20.21) were associated with paternal PPD.

Conclusion:  Paternal PPD is a clinically meaningful phenomenon. Fathers should be evaluated for mood disorders in the postpartum, especially when their partner is depressed.
Resorbable barrier and envelope flap surgery in the treatment of human gingival recession defects
Authors: Trombelli Leonardo , Scabbia Alessandro , Tatakis Dimitris N. , Checchi Luigi , Calura Giorgio
Published: December 2005

Abstract. The present case report evaluates the treatment outcome following mucogingival surgery combined with a bioresorbable barrier in gingival recession defects in humans. A total of 11 buccal, Miller Class I or II, gingival recession defects in 6 patients were consecutively treated. The exposed root surface was ultrasonically scaled and conditioned with a tetracycline HCI solution (10 mg/ml) for 4 min. A buccal full/split thickness envelope flap was then elevated, and a bioresorbable matrix barrier was positioned to completely cover the exposed root surface and surrounding bone margins. A flap was then positioned at or slightly coronal to its original position. In all cases, a variable amount of membrane was intentionally left uncovered on the exposed root surface. Clinical recordings, assessed presurgery and at 6 months postsurgery, included defects‐specific plaque and gingival scores, recession depth (RD), probing depth (PD), clinical attachment level (CAL) and keratinized tissue width (KT). Immediately postsurgery, and at weeks 1, 2, 4, 6 and 8 postsurgery, the location of gingival margin or granulation tissue covering the previously exposed root surface was recorded, as well as the extent of barrier exposure. Statistical analysis showed that RD decreased from 2.3±0.2 mm presurgery to 0.8±0.5 mm at 6 months postsurgery (p=0.001), representing a mean root coverage of 65% (range: 40–100%). CAL gain paralleled RD reduction (l.5±0.5 mm: p=0.0009), while KT showed a slight increase (0.3±0.6 mm) at 6 months postsurgery. Results indicate that clinical improvement of gingival recession defects may be achieved by means of a barrier‐supported envelope technique. The bioresorbable matrix barrier represented an effective scaffold to support the reconstruction of the mucogingival unit.
The effect of a single scaling with or without oral hygiene instruction on gingival bleeding and calculus formation
Authors: Lembariti B. S. , van der Weijden G. A. , van Palenstein Helderman W. H.
Published: December 2005

Abstract. 136 students of both sexes aged 14–18 years who were deprived of regular dental care participated in a 22‐month longitudinal study. All students underwent scaling of the assigned teeth in 2 quadrants according to a randomized split‐mouth design on contralateral quadrants. 2 groups of students were formed, one group received oral hygiene instruction (OHI). Follow‐up‐examinations on gingival bleeding and calculus were carried out 6, 12, and 22 months after the scaling session. The prevalence of calculus on assigned teeth at baseline was high with a mean score of 1.10. At the end of the study, new calculus formation on scaled teeth reached a mean score of 0.58. Formation of calculus still continued on non‐scaled teeth, but at a lower rate than on scaled teeth. Scaling resulted in an approximately 20% reduction of the gingival bleeding score which remained during the 22 months follow‐up period, OHI had no significant effect on the calculus and bleeding scores. Since the effect of scaling alone on the gingival condition was small and the effect of a single OHI negligible, the practice of occasional scaling without repeated OHI, which is commonly employed in developing countries, should be considered as clinically irrelevant and of little use in improving the standard of periodontal health.
Increased bFGF level in the serum of patients with phenytoin‐induced gingival overgrowth
Authors: Sasaki Toshiaki , Maita Eikichi
Published: December 2005

Abstract. To elucidate the involvement of bFGF (basic fibroblast growth factor) in the pathogenesis of phenytoin‐induced gingival overgrowth, we measured the concentration of bFGF in the serum of 36 epileptic patients taking phenytoin and in 94 normal volunteers by enzyme‐linked immunosorbent assay technique. The concentration of phenytoin in serum was determined by high‐performance liquid chromatography. In 34 of 36 patients taking phenytoin in this investigation, apparent gingival overgrowth was noticed. The mean concentration of bFGF was 33.9±18.5 pg/ml in the overgrowth group and 10.6±5.2 pg/ml in the volunteer group (p<0.01). The serum phenytoin level did not correlate (r=0.22, p= 0.2) with the degree of gingival overgrowth but there was a significant correlation (r=0 38, p=0.023) between the degree of gingival overgrowth and the serum bFGF level. However, no correlation was observed among age, daily phenytoin dose, total phenytoin dose, duration of phenytoin therapy, serum phenytoin level, or serum bFGF level. The results suggested that enhanced serum bFGF level was implicated in the pathogenesis of phenytoin‐induced gingival overgrowth.
Effects of transforming growth factor‐β and platelet‐derived growth factor on human gingival fibroblasts grown in serum‐containing and serum‐free medium
Authors: Anderson Thomas J. , Lapp Carol A. , Billman Michael A. , Schuster George S.
Published: December 2005

Abstract. Both transforming growth factor‐β (TGF‐ß) and platelet‐derived growth factor (PDGF) have been shown to affect cell proliferation in vitro. The hypothesis being tested was that the effects of the 2 cytokines would be modulated by the presence of serum in the medium. Gingival fibroblasts, obtained from periodontally healthy patients, were maintained in primary culture. Dose response experiments were performed for each growth factor in serum‐free medium and in medium containing natural or heat‐inactivated fetal bovine serum (10% FBS). Changes in cell numbers were quantified by crystal violet staining. The optimal concentrations of the individual factors (10 ng/ml TGF‐ßI, 20 ng/ml PDGF‐BB) were then used when the 2 factors were tested in various sequences. In serum‐free medium or in medium with 10% natural serum, the response to PDGF‐BB was dose‐dependent up to 40 ng/ml; however, with 10% heat‐inactivated serum, the maximal response was seen at 20 ng/ml. The largest increase in cell numbers was produced by the simultaneous exposure to the two cytokines, rather than a sequential presentation. The findings suggest that the 48‐h growth response of human gingival fibroblasts to 10 ng/ml TGF‐ß1 or 20 ng/ml PDGF‐BB in serum‐free medium was equivalent to growth obtained in medium containing heat‐inactivated 10% FBS without added growth factors.
The effect of a one‐stage full‐mouth disinfection on different intra‐oral niches Clinical and microbiological observations
Authors: Bollen Curd M. L. , Mongardini Claudio , Papaioannou William , Van Steenberghe Daniel , Quirynen Marc
Published: December 2005

Abstract. A treatment for periodontal infections often consists of consecutive rootplanings (per quadrani, at a 1‐to 2‐week interval), without a proper disinfection of the remaining intra‐oral niches (untreated pockets, tongue, saliva, mucosa and tonsils). Such an approach, could theoretically lead to a reinfection of previously‐treated pockets. The present study aims to examine the effect of a full‐mouth disinfection on the microbiota in the above‐mentioned niches. Moreover, the clinical benefit of such an approach was investigated. 16 patients with severe periodontitis were randomly allocated to a test and a control group. The patients from the control group were scaled and rootplaned, per quadrant, at 2‐week intervals and obtained oral hygiene instructions. The patients from the test group received a full‐mouth disinfection consisting of: scaling and rootplaning of all pockets in 2 visits within 24 h, in combination with tongue brushing with 1% chlorhexidine gel for 1 min, mouth rinsing with a 0.2% chlorhexidine solution for 2 min and subgingival irrigation of all pockets (3× in 10 min) with 1%, chlorhexidine gel. Besides oral hygiene, the test group rinsed 2× daily with 0.2% chlorhexidine and sprayed the tonsils with a 0.2% chlorhexidine for 2 months. Plaque samples (pockets, tongue, mucosa and saliva) were taken at baseline and after 2 and 4 months, and changes in probing depth, attachment level and bleeding on probing were reported. The full‐mouth disinfection resulted in a statistically significant additional reduction/elimination of periodonlopathogens, especially in the subgingival pockets, but also in the other niches. These microhiological improvements were reflected in a statistically‐significant higher probing depth reduction and attachment gain in the test patients. These findings suggest that a disinfection of all intra‐oral niches within a short time span leads to significant clinical and microbiological improvements for up to 4 months.
Clinical expression of TNF‐α in smoking‐associated periodontal disease
Authors: Boström Lennart , Linder Lars E. , Bergström Jan
Published: December 2005

Abstract. The level of TNF‐α in gingival crevicular fluid (GCF) was analyzed with respect to smoking in patients with untreated moderate to severe periodontal disease including 30 current smokers, 19 former smokers and 29 non‐smokers, in the age range 31–79 years, Concomitantly the occurrence of the periopathogens Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) and the GCF levels of albumin, IgA and IgG were analyzed. With regard to clinical characteristics, there were no statistically significant differences between smoking groups. The occurrence of patients positive for the periopathogens Aa, Pg and Pi was 28.2%, 41.0% and 91.0%, respectively. There were no statistically significant differences between smoking groups with regard to occurrence or relative frequency of these periopathogens. An exception was a significantly lower occurrence of Aa in former smokers as compared to non‐smokers. The chief novelty of the study was the observation of a clearly increased level of TNF‐α in GCF associated with smoking. Both current and former smokers exhibited significantly higher levels of TNF‐α in comparison to non‐smokers, whereas the levels of albumin, IgA and IgG were the same irrespective of smoking. In conclusion, the present observations in patients with moderate to severe periodontal disease suggest that smoking is associated with elevated GCF levels of the cytokine TNF‐α.
Clinical and antimicrobial effects of a single episode of subgingival irrigation with tetracycline HCI or chlorhexidine in deep periodontal pockets
Authors: Stabholz Ayala , Nicholas Anne A. , Zimmerman Grenith J. , Wikesjö Ulf M. E.
Published: December 2005

Abstract. 15 adults, each providing 4 non‐adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm. volunteered for a randomized, split‐mouth, double‐blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%). TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post‐irrigation mechanical plaque control was supported by 2× daily CHX rinses throughout the 12‐week observation interval. Recordings of oral hygiene (PlI), gingival health (GI). bleeding on probing (BoP). probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre‐irrigation. and at 1, 2, 4, 6, 8, 10, and 12 weeks post‐irrigation. Mean post‐irrigation PlI was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre‐irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre‐irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post‐irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre‐irrigation for TTC10. CHX and control sites over the 12‐week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post‐irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a rôle in the management of adult periodontitis.
Oral hygiene and gingivitis in a Swedish adult population 1973, 1983 and 1993
Authors: Hugoson Anders , Nordery Ola , Slotte Christer , Thorstensson Helene
Published: December 2005

Abstract. The periodontal condition of the inhabitants of Jönköping County, Sweden was followed for 20 years by means of 3 cross‐sectional investigations performed in 1973, 1983, and 1993. The study comprised individuals in the age groups 20, 30, 40, 50, 60, and 70 years. The number of dentate individuals was 537 in 1973, 550 in 1983, and 552 in 1993. All individuals participating in the studies were examined clinically and radiographically. They also filled out a questionnaire about dental care habits, socio‐economic status, and general health. A clear reduction in the plaque score was seen between 1973 and 1983 in all age groups. With one exception, no further significant change in plaque levels was found between 1983 and 1993: the increase in plaque among the 20‐year‐olds was significant. In 1993 the mean % of surfaces with plaque was between 30% and 40% in all age groups. Gingivitis values corresponded well with the values of dental plaque: the same pattern with a clear reduction in gingivitis score was seen in all age groups between 1973 and 1983, and an increase in the mean frequency of gingival inflammation between 1983 and 1993 was seen in the 20‐year age group. 30% of the individuals in this age group had more than 50% gingivitis in 1993 compared with 9% of the individuals in 1983. The 20‐year‐olds were further analyzed in a linear regression model using gingivitis as a dependent variable against some socio‐economic, general health, and dental care variables associated with poor oral hygiene and gingivitis. In 1993, the most important explanatory variable was gender: significantly more males than females had higher gingivitis scores. The second most important explanatory variable was toothbrushing habits. Together they explained 10.9% of the variance. The multivariate analysis did not reveal approximal cleaning habits to be significant, probably due to their strong connection to gender and toothbrushing habits. In the 1983 sample, no significant explanatory variables were found. It was concluded from this data that it is important not only to renew but also to direct preventive guidelines more towards young adults who have no previous extensive experience of oral disease so that they will not be excluded from dental care and their dental health thereby jeopardised. In addition to preventive programmes aimed at the population as a whole, individual programmes based on risk targeting are also necessary to reduce the number of people developing dental disease and to increase the quality of dental care.
The effects of a potassium citrate, cetylpyridinium chloride, sodium fluoride mouthrinse on dentine hypersensitivity, plaque and gingivitis
Authors: Yates R. , West N. , Addy M. , Marlow I.
Published: December 2005

Abstract. Home‐use studies on dentine hypersensitivity have most commonly involved toothpastes and rarely have mouthrinses been employed. Potassium and/or fluoride toothpastes have been shown effective in the treatment of dentine hypersensitivity The aim of this study was to evaluate the effectiveness of a total formulation, containing potassium citrate, sodium fluoride, cetylpyridinium chloride mouthrinse compared to the base rinse minus actives in the reduction of dentine hypersensitivity. The study was a randomised placebo controlled, double blind parallel design. At a screening visit, 90 adult subjects were recruited who were suffering from dentine hypersensitivity from at least 1 tooth responding to tactile stimulation (45gm pressure) and had at least 2 teeth responding to evaporative stimulation (air blast). During a washout period of 28 days and throughout the 56‐day study period, subjects used a soft filament toothbrush and standard fluoride toothpaste. At baseline (day 1), threshold sensitivities to incremental tactile (10 g to 70 g) and evaporative stimuli were determined. Gingival health was assessed by recording bleeding on probing at 25 g pressure at mesiobuccal and lingual sites. Plaque scores from buccal and lingual surfaces of disclosed teeth were also measured. Subjects then used the prescribed rinse. 10 ml for at least 30 s after brushing 2× per day returning on days 28 and 56 for rescoring of sensitivity, gingivitis and plaque. Data from 88 subjects were used with the intent to treat analyses and 83 in the completely evaluable analyses. Groups were well balanced for demographic data and product returns suggested good compliance. Both groups showed highly significant improvements in tooth sensitivity. The pattern was for greater improvement in the test compared to the control group (statistically significant for the plaque score), whereas bleeding scores, already low, showed no change in either group. By definition, the placebo rinse could not have exerted any therapeutic action; the study therefore provides clear direct evidence as to the magnitude (30%‐40%) of the little studied, but assumed, placebo response in dentine hypersensitivity trials.
Effectiveness of a sonic toothbrush in maintenance of dental implants
Authors: Wolff Larry , Kim Alex , Nunn Martha , Bakdash Bashar , Hinrichs James
Published: December 2005

Abstract. This study assessed the efficacy of a sonic and a manual toothbrush in reducing plaque and gingivitis around dental implants. Subjects were randomly assigned to either sonic (n=16) or manual (n=15) study groups. Groups were balanced according to baseline levels of plaque and gingivitis. The plaque (PI), gingival (GI), and bleeding (BI) indices as well as probing depths were determined at baseline, and at 4, 8, 12, and 24 week follow‐up visits. Mean scores per person were calculated for each clinical parameter. Oral hygiene habits, compliance and acceptance were also evaluated over the study period. Within group comparisons from baseline throughout the study, as well as between group comparisons (i.e., sonic versus manual), were determined. Overall, plaque, gingival, and bleeding indices in both groups were lower at each follow‐up visit when compared to the baseline. Within group comparisons demonstrated that both the sonic toothbrush subjects and the manual toothbrush subjects had significantly lower PI. GI. and BI scores at each post‐baseline visit (4, 8, 12, and 24 weeks) than at baseline (p<0.005), In addition, the sonic toothbrush subjects also had significantly lower probing depths at each post‐baseline visit than at baseline (p<0.005). Between group comparisons demonstrated that the sonic toothbrush subjects over time had significantly lower PI and BI scores around dental implants than the manual toothbrush subjects (Repeated measures MANOVA; PI, p=0.01; BI, p= 0.017). The sonic toothbrush subjects had lower GI scores and reduced probing depths over time when compared to manual toothbrush subjects but these scores were not statistically significant (GI; probing depth, p > 0.05). No implant problems (e.g., loose screws) were attributable to the sonic toothbrush. Relevant to oral hygiene habits, subjects in both groups demonstrated a high level of compliance with their assigned toothbrush. Overall, the results of this study demonstrated that sonic toothbrushing significantly reduced plaque, gingival inflammation and bleeding, and probing pocket depths around implants over the 6‐month trial period. It is concluded that sonic brushing is an effective means of dental implant maintenance.
Alveolar ridge reconstruction and/or preservation using root form bioglass cones
Authors: Yilmaz Selçuk , Efeoǧlu Elvan , Kiliç Ali Riza
Published: December 2005

Abstract. Extraction of a tooth necessitated by factors such as developmental problems, trauma, severe periodontal disease and endodontic problems often causes deformities of the residual alveolar ridge in the maxillary anterior region. These cases are usually difficult to restore prosthetically and they result in poor esthetics and insufficient occlusal function. This study investigated the efficacy of root form bioactive glass cones implanted into (a) artificial sockets produced by bone splitting of previous extraction sites (group BS) and (b) fresh extraction sockets (group FES), We included conventional extraction sockets sutured without implanting the root form bioactive glass cones as a control (group C). A total of 16 patients were treated for whom extractions had been indicated due to severe periodontitis, 6 patients with 7 implant sites having Class II or III alveolar ridge deformities comprised the BS group. 5 patients with 10 implant sites comprised the FES group. Group C, comprised 5 patients with 10 extraction sites. Alveolar ridge width and height measurements were obtained using study casts preoperatively, immediately postoperatively. and at 3 and 12 months after operation. In the BS group, while the width of the alveolar ridge increased by 2.8 ± 1.18mm immediately after ridge augmentation procedure and by 2.4±0.93 mm at 1 year after operation (p<0.01), the height of the alveolar ridge increased by 1.8±1.99 mm and 1.4±1.74 mm respectively (p<0.05). In the FES group, the differences between preoperative original ridge height and width and postoperative measurements were not statistically significant, which demonstrated the efficiency of this method in preserving the alveolar ridge. In group C, while alveolar ridge width after 12 months had not Significantly changed, alveolar ridge height decreased significantly (1.35±1.05 mm. p<0.01). After 12 months, no dehiscences were detected and the differences in height between the groups remained significant. The results of this study indicate that this procedure is efficient in reconstructing alveolar ridges deformed as a result of extraction, particularly relevant in relation to preparation for subsequent restorative treatment.