bluuebunny/crossref_metadata_2025 huggingface dataset:
Release of methyl methacrylate from heat‐curved and autopolymerized resins: Cytotoxicity testing related to residual monomer
Authors: Kedjarune Ureporn , Charoenworaluk Nongluk , Koontongkaew Sittichai
Published: March 2008

Three heat‐cured and three autopolmerized arcylic denture bases with different mixing proportions and/or processing methods were investigated for the amount of resdidual monomer content and methyl methacrylate (MMA) released into saliva after incubation during the first and second 24 house after processing. A corresponding range of concentrations of mma was also used to test for cell cytotoxicity using a culture of human oral fibroblasts. The results showed that the amount of residual monomer was dependent not only on the type of polymerization but also on the amount of liquid in the mixture ratio and the processing method. The acrylic resin that had the lowest residual monomer also released the smalllest amount of MMA but resins which have higher residual monomer may not necessarily release higher amounts of MMA. MMA, tested in the same range of concentration as the MMA found leached from acrylic resin in this study, was found to be toxic in the cell culture. Therefore, it is recommended that dentists attempt to reduce the amount of leachable substances before insertion of new dentures. In addition, it is recommended that dentists advise their patients not to wear newly made dentures overnight, as this may cause mucosal irritation from the potential accumulation of leachable substances.
Ethnic dental analysis of shovel and Carabelli's traits in a Chinese population
Authors: Hsu John W. , Tsai Pei L. , Hsiao Tin H. , Chang Hong P. , Liu Li M. , Liu Keh M. , Yu Hsin S. , Ferguson Donald
Published: March 2008

Chinese population differ from Caucasoids by having a high prevalence of shovel trait and a low prevalence of Carabelli's trait. This study was conducted to investigate the association between the shovel and the Carabelli's traits in a Chinese population. The research design investigated a Chinese population that resides in southern Taiwan. The ancestors of this Chinese population migrated to Taiwan from mainland China, mainly from Fukien and Kwangtung. The effects of sex and age on Carabelli's trait were controlled in this investigation, as was the association between tooth size and Carabelli's trait. Results show that males were more likely to have Carabelli's trait expressed on teeth than females. The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the trait. After controlling for sex, age, and tooth size, the existence of the shovel trait increased the likelihood of having Carabelli's trait by a factor of five and a half, which is a significant effect.
Restoring the vertical dimension of mandibular incisors with bonded ceramic restorations
Authors: Wylie S. G. , Tan H‐K. , Brooke K.
Published: March 2008

Mandibular incisors are difficult to restore with conventional anterior crowns due to their small axial diameters. Crown preparation risks pulp exposure and results in a thin core of dentine. An experiment was designed to determine if increasing the thickness of ceramic to restore incisal edges affects the load at the point of restoration failure. Forty‐eight mandibular incisors were randomly divided into four groups. The incisal edges of the teeth in three groups were reduced so that the coronal height was 7.5 mm (Group A), 6.5 mm (Group B), and 5.5 mm (Group C). Group D was designated as the experimental control. A fifth group (Group E), independent of the random sample, was introduced to the study for discussion purposes and was characterized by each of the incisors having an intact incisal edge of enamel. Groups A, B and C were prepared in a standard fashion for cermaic veneer restorations that were constructed to restore the vertical height of each tooth to 8.5 mm. Prior to cementation, the preparation surfaces were analysed and the relative surface areas of enamel and dentine were calculated. The ceramic restorations were cemented using a resin luting agent. The teeth were then thermocycled prior to loading at 135d̀C until failure. The mean fracture load was 305 N (SD 134 N) for Group A, 403 N (SD 101 N) for Group B, 515 N (SD 296 N) for Group C, 587 N (SD 187 N) for Group D and 395 N (SD 129 N) for Group E. As determined by analysis of variance followed b a Sheffè multiple comparison test there was a significant difference (p£0.01) between Group A and Group D. There were no significant correlations of load at failure with the percentage of exposed dentine, enamel surface area, total preparation surface area, and the incisal surface area. The patterns of failure of the fractured specimens were also analysed. There were significantly (p£0.05) greater fractures of the ceramic restorations when they were bonded with the minimum incisal thickness of ceramic.
The surface effect of dentifrices
Authors: Meyers I. A. , McQueen M. J. , Harbrow D. , Seymour G. J.
Published: March 2008

The aim of this study was to evaluate clinically three commercially available dentifrices and to determine any surface effects on tooth or gingival surfaces. Sixty‐four participants were included in this study and were allocated randomly to one of four treatment groups by an independent person to ensure the investigators were unaware of the brushing material used. All toothbrushes and dentifrices were distributed by this independent person. The treatment groups were: Group 1‐ brush with water; Group 2 ‐ brush with colgate (Baking Soda nad Peroxide); Group 3‐ brush with Colgate (Sensation Whitening).

All participants were requested to brush both morning and evening in their customary fashion using only the designated toothpaste, or water, for four weeks. All participants were required to use the same toothbrush type. No other oral hygiene products such as mouth rinses or dental floss were used during the trial period. Prior to commencement of the brushing period, all participants received a full clinical examination recording the status of the soft and hard tissues including a ginginval index (Löe and Silness) to record gingival condition. A polyvinyl siloxane impression was taken of the six anterior teeth and gingival tissues at the commencement of the trial. After four weeks, a second full clinical examination was made and further silicone impressions were taken of the anterior teeth. All impressions were cast in epoxy resin for investigation with light and electron microscopy. Participants were also asked to answer a questionnaire relating to the toothpaste used. The results of this study indicated that no significant clinical differences were recorded for any dentifrice or water and there was no significant difference in gingival index scores over the four week period. Patient responses to each dentifrice varied according to individual patient preferences and expectations and no consistent findings could be determined. Light and electron microscopy indicated that tooth and gingival surface changes that occurred over the four week period with any of the dentifrices were similar to, and not significantly different from, changes seen with the use of water alone. These results indicate that none of the dentifrices tested was harmful to teeth or soft tissues.
Clinical assessment in dental education: A new method
Authors: Tennant Marc , Scriva Jose
Published: March 2008

Among the many challenges that face modern dental schools is the development of appropriate assessment systems. The more litigious nature of modern education makes it important that the systems developed are transparent and can withstand the processes of legal challenge. Coupled with this demand for robust assessment is a growing demand from universities and health providers for dental schools to keep rigorous records of student clinical productivity. This brief review outlines a system developed at the School of Oral health Sciences at the University of Western Australia. The system integrates both qualitative and quantitative assessment and uses criterion‐based assessment as its foundation. Detailed analysis and real‐time reporting mechanisms using a suite of personally written software tools is now possible. The system provides both students and staff with effective data to enhance the learning process.
Continuing dental education in osseointegrated implants. A survey
Authors: Brandt RL , Fitzpatrick BJ , Moloney FB , Bartold PM
Published: March 2008

A survey of participants in a continuing education course in osseointegrated implants was carried out to determine dentists' attitudes toward such courses and how they were integrating implants into their everday practice. The results indicated, despite the intense program, very few general dentists who attended such a course chose to actively participate in implant placement and a moderate number chose to carry out prosthetic restoration. Those who attended such courses appeared satisfied with the course content, appreciated the difficulties involved with implant placement and restoration and generally chose to refer such cases to appropriate specialists for management. This pilot study confirms dental implants are a popular and accepted mode of therapy. However, general dental practitioners who take the time to undergo specific training in osseointegrated implants appear to be less inclined to actively participate in the placement (surgery) of implants. Following appropriate training, many general practitioners felt comfortable in performing the restorative/prosthetic aspect of implant treatment of single tooth rather than partial of full denture cases. In conclusion, while continuing education courses in osseointegrated implants are becoming increasingly popular, this survey indicates participants become aware of the complexity of the procedures involved and tend to actively participate mainly in the prosthetic reconstruction of simple cases.
Antibiotic prescribing practices by South Australian general dental practitioners
Authors: Jaunay Tom , Dambrook Paul , Goss Alastair
Published: March 2008

The prescribing habits of a randomly selected approximately 10 per cent sample of South Australian general dental practitioners were obtained by postal questionnaire. Sixty‐eight (61 per cent) usable replies were received and analysed. Generally, there was an appropriate level of knowledge of antibiotic prescription. However, there was a tendency toward over‐prescription and a demonstrated lack of knowledge of the incidence of adverse reactions, development of multiresistant strains and prophylaxis against bacterial endocarditis. All of these areas are real challenges to the profession, whether in an overall global community health sense or in a highly individualized clinical or medico‐legal sense. These issues are discussed and the profession is urged to reconsider and re‐educate itself on these challenges.
A survey of the distribution and types of full crowns prescribed in Melbourne, Australia
Authors: Stankiewicz Nikolai Ramsay , Wilson Peter Robert
Published: March 2008

The full crowns made by 11 commercial dental laboratories in Melbourne, Australia, were surveyed over a two‐month period. The survey was designed to find which teeth were crowned and what types of full crowns were prescribed. Maxillary central incisors were found to be the most frequently crowned teeth (15.6 per cent) and porcelain‐fused‐to‐metal crowns were the most commonly prescribed type of crown (82.9 per cent). This study may form a baseline with which other Australian studies may be compared and contrasted.
In vitro fluoride release from aesthetic resorative materials following recharging with APF gel
Authors: Peng Dong , Smales Roger J. , Yip Hak Kong , Shu Man
Published: March 2008

In this in vitro study, the fluoride ion release from three more‐viscous conventional glass ionomer cements (GICs) ‐ ChemFlex, Fuji IX GP, lonofil Molar ‐ four polyacid‐modified resin composites (compomers) ‐ Dyract AP, Compoglass F, Freedom, F2000 ‐ and a hybrid resin composite ‐ Ariston pHc ‐ were compared. The amounts of fluoride release from 3b2.7mm specimens were measured over six weeks using a fluoride ion‐selective electrode. After six weeks, the specimens were recharged with 2ml of 1.23 per cent acidulated phosphate fluoride (APF) gel for four minutes. The recharged specimens were then assessed for the amounts of fluoride release over another six weeks. Statistical analyses were performed using one‐way and repeated measures ANOVA. The GICs and Compoglass F showed significantly higher initial fluoride release rates during the first two days (p<0.05). After the first two days, fluoride release rates from all materials dropped quickly and became essentially stabilized within three‐five weeks, in an exponential mode. The recharging of the specimens with APF gel caused a brief, but significant, increase in fluoride release for all materials (p<0.05), before decreasing to previous comparable rates. Compoglass F released relatively more fluoride, and Ariston pHc relatively less, after APF gel application than before. The lowest total amounts over the study were released by Dyract AP and Freedom. The newer compomers, as well as the newer more‐viscous GICs, appear to act as fluoride reservoirs to varying extents.
The increasing problem of hepatitis C virus infection
Authors: Coates EA , Walsh L. , Logan R.
Published: March 2008

The widespread incidence of hepatitis C (HCV) infection throughout the community is of concern. Although many of those infected will not suffer significantly from their infection, up to one‐third will have liver disease, fatigue and oral health problems. General dental practitioners need to be aware of the precautions necessary in traeating people with severe liver disease. This paper discusses the issues associated with treating patients who have HCV infection including the importance of preventive programs to reduce dental pathology and maximise oral health.
Dental Complications of Head and Neck Radiotherapy: Part 2
Authors: Andrews Nectarios , Griffiths Chris
Published: March 2008

Radiotherapy for head and neck tumours is a viable treatment modality. However, a wide range of potentially debilitating dental complications may accompany the treatment. In Part 2 of this article, prevention and management strategies available to the dental practitioner to stave off the dental side effects of radiotherapy are explored and particular attention is given to the management of xerostomia and radiation caries.
A Radiographic Assessment of the Prevalence of Pulp Stones in Australians
Authors: Ranjitkar S. , Taylor JA , Townsend GC
Published: March 2008

Background: Pulp stones are discrete calcified bodies found in the dental pulp. The aims of this study were to calculate the prevalence of pulp stones in young Australian adults using radiographs, and to report any associations between occurrence of pulp stones and sex, tooth type, dental arch, side and dental status.

Methods: From 217 undergraduate dental students, comprising 123 males and 94 females aged between 17–35 years, 3296 teeth were examined under 2x magnification on bitewing radiographs. Pulp stones were scored as present or absent, and associations with sex, tooth type, dental arch, side and dental status noted.

Results: Pulp stones were found in 100 (46.1 percent) of the subjects and 333 (10.1 per cent) of the teeth examined. Occurrences were rare in premolars (0.4 per cent) but significantly higher in molars (19.7 per cent). Pulp stones were significantly more common in first molars than in second molars, and in maxillary first molars than in mandibular first molars. Carious and/or restored maxillary right first molars and maxillary left second molars displayed higher prevalences of pulp stones than unrestored and intact molars.

Conclusion: Pulp stones may provide useful forensic information when examining dental records to identify deceased persons.
Oral Cancer in Australia: 1983–1996
Authors: Sugerman PB , Savage NW
Published: March 2008

Background: The aims of this study were to identify differences in oral cancer incidence and mortality between sexes, age groups, oral sites and Australian States and Territories and recent trends in oral cancer incidence, mortality and age‐profile over time.

Methods: Data were obtained from the Australian Institute for Health and Welfare and were age‐standardized to the Australian 1991 Population Standard. Differences and trends were assessed with the Wilcoxon matched‐pairs signed‐ranks test and the Spearman correlation test, respectively.

Results: In Australia in 1996, there were 2173 new oral cancers and 400 deaths due to oral cancer, the majority of oral cancers were in the 60+ age group, oral cancer affected men more than women (>2:1), lip cancer accounted for more than 50 per cent of oral cancers and the oral cancer mortality‐to‐incidence (M:I) ratio was greatest in ACT and NSW and least in QLD and SA. From 1983 to 1996, the annual incidence of lip cancer increased while the M:I ratio of lip cancer decreased. The annual incidence of cervical cancer decreased whereas the annual incidence of intra‐oral cancer remained constant. The M:I ratio of cervical cancer was consistently lower than the M:I ratio of intra‐oral cancer.

Conclusions: Reducing exposure to environmental carcinogens, increasing public awareness and population screening may reduce the incidence and mortality of oral cancer in Australia.
Chronic Dental Infections Mimicking Temporomandibular Disorders
Authors: Ogi N. , Nagao T. , Toyama M. , Ariji E.
Published: March 2008

Background: Trismus and jaw pain are not only caused by temporomandibular disorders (TMD), but also by various pathologies, namely infection, trauma, or neoplasms. TMD‐like symptoms, as a result of the pathologies, may be confusing to a clinician. This paper reports two cases of chronic dental infection mimicking TMD.

Methods: Two patients were initially diagnosed with, and treated for, TMD. However, the patients did not respond to the treatment. Limited range of motion and jaw pain were then clinically evaluated for differential diagnoses. Laboratory examinations and computerized tomography (CT) scans were carried out to disclose any underlying lesion.

Results: Laboratory examination, such as, C‐reactive protein helped to detect latent infection. CT scans revealed insidious chronic dental infection imitating TMD. Surgical drainage and chemotherapy resolved the symptoms.

Conclusion: The importance of a rational diagnostic process, including clinical and laboratory examinations and radiologic imaging, cannot be over‐emphasized in elucidating true cause of the symptoms.
A Survey of Dental and Oral Trauma in South‐East Queensland During 1998
Authors: Wood EB , Freer TJ
Published: March 2008

Background: This project investigated the aetiology of dental and oral trauma in a population in southeast Queensland. The literature shows there is a lack of dental trauma studies which are representative of the general Australian population.

Method: Twelve suburbs in the south‐east district of Queensland were randomly selected according to population density in these suburbs for each 25th percentile. All dental clinics in these suburbs were eligible to participate. Patients presenting with dental and oral trauma were eligible to participate.

Results: A total of 197 patients presented with dental/oral trauma over a 12 month period. The age of patients ranged from 1–64 years whilst the most frequently presenting age group was 6–10 years. There was a total of 363 injured teeth with an average of 1.8 injured teeth per patient. Males significantly outnumbered females in the incidence of trauma.

Conclusions: The highest frequency of trauma occurred in the 6–10 year age group. Most injuries in this group occurred while playing or riding bicycles. In the next most prevalent trauma group, 16–20 years, trauma occurred as a result of fighting and playing sport. Overall, males significantly outnumbered females by approximately 1.8: 1.0. The majority of injuries in the deciduous dentition were to periodontal tissues. In the secondary dentition most injuries were to hard dental tissue and pulp.
Screening for Latex Allergy with A Questionnaire: Comparison with Latex Skin Testing in a Group of Dental Professionals
Authors: Katelaris CH , Widmer RP , Lazarus RM , Baldo B.
Published: March 2008

Background: Latex allergy has emerged as an important cause of allergic reactions particularly in health workers. Due to the lack of a standardized extract for objective skin testing a screening questionnaire was developed.

Methods: At the 1995 Australian Dental Association Conference, all attendees were invited to complete a questionnaire and undergo skin testing to assess the level of latex allergy in this population and to assess the performance of the questionnaire as a screening test for latex allergy.

Results: The questionnaire had high specificity but poor sensitivity compared to skin testing with latex extract.

Conclusion: This study compares at risk individuals identified by a screening questionnaire with those identified by objective skin testing. A questionnaire designed to screen for latex allergy was reliable for identifying those with low risk whhile overestimating those at risk of true latex allergy, demonstrating the need for objective testing with reliable allergens.
Arthritis and Use of Dental Services: A Population Based Study
Authors: Pokrajac‐Zirojevic V. , Slack‐Smith LM , Booth D.
Published: March 2008

Background: Rheumatoid arthritis (RA) and osteoarthritis (OA) are chronic systemic conditions that can have a profound effect on oral health as the result of physical disability, immunosuppressant and other medications and autoimmune disease. However, there is insufficient information available on the use of dental services by the people suffering from RA or OA. The purpose of this study was to investigate dental visits and factors associated with dental attendance in those with RA and OA in order to improve access to dental care in these groups.

Methods: The study used population based data from the 1995 National Health Survey (total n=53 828). The main variables of interest were reported RA (n=1193) and OA (n=3091) and the main outcome variable was having visited a dental professional in the previous 12 months. Chi‐square analysis was performed using SAS software.

Results: The proportion of people visiting a dental professional in previous 12 months was significantly less in both RA and OA respondents compared to non‐arthritic respondents. Both males and females with RA and OA were found to be less likely to have visited a dental professional when compared to general population (p=0.001 in each case). Furthermore, the findings have revealed that RA and OA patients living in metropolitan centres were more likely to have a dental visit than those living in rural or remote areas (p=0.001 in each case).

Conclusions: When compared to non‐arthritic subjects, all patients with RA and OA were less likely to receive dental care, in particular preventive care. This is especially important in patients with Sjögren's Syndrome and those who are immunosuppressed.
Current concepts in the management of oral squamous cell carcinoma
Authors: Spencer KR , Ferguson JW , Wiesenfeld D.
Published: March 2008

This paper focuses on how patients with oral squamous cell carcinoma (SCC) are assessed and managed once they have been referred for specialist care. Current and future treatment options are presented and basic management principles are discussed. It is our hope that this will enable the general dental practitioner to gain insight into the process and reasoning behind the multidisciplinary treatment of these complex cases.
Oral lichen planus: Causes, diagnosis and management
Authors: Sugerman PB , Sabage NW
Published: March 2008

Oral lichen planus (OLP) is a chronic inflammatory disease of unknown etiology. In this paper we review the clinical and histological features of OLP, process of OLP diagnosis, causes of OLP, management of OLP patients and medical treatment of OLP lesions. Approximately 0.2 per cent OLP patients develop intra‐oral carcinoma each year compared with approximately 0.005 per cent Australian adults. Possible mechanisms of increased oral cancer risk in OLP patients are presented. The aims of current OLP therapy are to eliminate mucosal erythema and ulceration, alleviate symptoms and reduce the risk of oral cancer. Patient education may improve the outcomes of OLP therapy and further reduce the risk of oral cancer in OLP patients. Although OLP may be diagnosed clinically, appropriate specialist referral is required for: (i) histological diagnosis; (ii) assessment of causative/exacerbating factors, associated diseases and oral cancer risk; (iii) patient education and management; (iv) medical treatment; and (v) long‐term review and re‐biopsy as required.
Caries Inhibitory Effect of Fluoridated Sugar in a Trial In Indonesia
Authors: Mulyani D. , McIntyre J.
Published: March 2008

Background: In some regional areas of Indonesia, caries prevalence is increasing rapidly. As water, salt or milk fluoridation were not considered suitable for use throughout Indonesia, and fluoridated tooth paste is mostly too expensive, a fluoride co‐crystallised sugar containing 10ppm fluoride was prepared. Its efficacy in inhibiting caries development was tested in a field trial.

Methods: The field trial was established in Medan, Sumatera. All dietary background data necessary to ensure the safety of a trial were collected. Subjects chosen were 176 children who were residents of two orphanages and a boarding school for children of poor rural families. The trial used a double‐blind format. Close monitoring of fluoride consumption was maintained, and fluoride excretion rates were assessed six monthly by urinary fluoride analysis.

Results: Records of total tooth surface caries present initially and after 18 months of sugar supply showed that the children using fluoridated sugar had significantly fewer carious lesions than those who used normal sugar.

Conclusion: This result indicates that sugar might be considered as a further vehicle for supplementary dietary fluoride in communities where there is a high caries prevalence or high caries risk and little exposure to fluoride.
Resin modified glass‐ionomers: Strength, cure depth and translucency
Authors: Mount GJ , Patel C. , Makinson OF
Published: March 2008

Background: According to the classification suggested by McLean, Wilson and Nicholson only three materials, currently marketed, fit the designation of resin modified glass‐ionomers. These materials will undergo an acid/base setting reaction but also contain a limited quantity of a monomer that will polymerize as a result of irradiation. The quantity of polymer is limited to the extent that it will not interfere with the normal acid/base setting reaction and will therefore allow for the ion exchange adhesion with tooth structure that is typical of glass‐ionomer. There is a third setting reaction incorporated to ensure remaining monomer, that is not affected by irradiation, will still polymerize. A series of experiments were carried out to determine the effect of the three types of setting reaction on the strength, depth of cure and translucency of these three materials.

Methods: Specimens, both with and without irradiation, were subjected to a shear punch strength test. To determine the depth of cure brought about through irradiation, specimens were tested immediately after construction according to the test in ISO ‐ 4049 2000 (E). Translucency is clinically significant and will vary according to whether the material has been subjected to irradiation or cured through the acid/base reaction alone.

Results: The strength of all materials tested was higher in specimens subject to irradiation. The depth of cure was found to be both shade and irradiation time dependent. Irradiated specimens were found to be only marginally more translucent than those allowed to set without irradiation.

Conclusions: It was concluded that, for cavities more than 3mm deep, these materials should be placed incrementally to allow for a full irradiation initiated cure.
Foreign bodies in the maillary antrum: A case report
Authors: Liston PN , Walters RF
Published: March 2008

A case is presented where six gutta percha (GP) points were introduced into the right maxillary antrum during routine endodontic treatment on an upper second premolar tooth in a poorly controlled insulin‐dependent diabetic. The surgical management of the case is described and the possibly more serious sequelae are discussed. Comments are made on the appropriateness of the treatment plan.
Submandibular gland aplasia and progressive dental caries: A case report
Authors: Fracaro MS , Linnett VM , Hallett KB , Savage NW
Published: March 2008

When severe caries occurs in mandibular permanent incisor teeth, the clinician should consider the possibility of associated submandibular gland aplasia or salivary hypofunction. Early diagnosis of submandibular gland disease is essential, as operative problems involving restoration of mandibular incisor teeth are considerable. Furthermore, progressive severe dental caries can present a dilemma for the clinician in affected individuals, despite intensive preventive and restorative therapy. A case report describing severe progressive dental caries and enamel demineralization of the permanent mandibular incisor teeth in a young girl is presented. Further investigation revealed absence of functional bilateral submandibular salivary glands contributing to the rapid breakdown of the teeth despite intensive preventive measures.
Tooth wear prevention: A quantitative and qualitative in vitro study
Authors: Kaidonis JA , Gratiaen J. , Bhatia N. , Richards LC , Townsend GC
Published: March 2008

Background: Management of tooth wear from grinding presents a significant clinical challenge. Acrylic nightguards are often used to protect the teeth, but many patients still grind with these appliances. This study aimed to test the effectiveness of three lubricants in reducing enamel wear by using an electro‐mechanical machine under controlled conditions, with a view to undertaking a subsequent longitudinal clinical study.

Methods: Sectioned tooth specimens were worn against each other under different loads and with the addition of three different lubricants: calcium fluoride (CaF) powder, olive‐oil, and a combination of calcium fluoride with olive‐oil in the form of a slurry. Wear rates of enamel only were quantified by weighing the specimens, and resin replicas of the worn tooth surfaces were made for examination under a scanning electron microscope.

Results: All three lubricants reduced the amount of enamel wear significantly compared with wearing specimens without adding lubricants. Wear rate was influenced by the type of lubricant and the load applied. Wear rates were significantly less for olive‐oil and the olive‐oil/CaF slurry compared with CaF alone. The microwear detail differed between the three lubricants.

Conclusions: This study has shown that enamel wear can be reduced using dry or wet lubricants between opposing teeth that are worn under controlled conditions. Further research is required to clarify their possible clinical applications.
Oral ulceration with bone sequestration
Authors: Farah CS , Savage NW
Published: March 2008

Oral mucosal ulceration is a common manifestation of various disease processes. Identification of the aetiological factor(s) involved greatly facilitates the management of such conditions. This report describes oral ulceration of the mucosa overlying the lingual shelf and mylohyoid ridge of the mandible and, less commonly on tori and exostoses, in association with bone sequestration. Trauma, which involves the subjacent periosteum resulting in a focus of ischaemic bone necrosis, in conjunction with local anatomical and perhaps other systemic predisposing factors, forms the aetiopathogenesis for this particular type of focal ulcerative lesion.
The value of twins in dental research
Authors: Townsend GC , Richards L. , Hughes T. , Pinkerton S. , Schwerdt W.
Published: March 2008

Due to recent advances in molecular genetics, studies of twins will continue to provide important insights into how genetic and environmental factors contribute to variation in human physical and behavioural traits and disorders. This review emphasizes that biometrical genetic studies of twins are particularly valuable in complementing and directing molecular approaches to facilitate the detection of quantitative trait loci. It also describes several other research models involving twins, apart from the traditional comparison of similarities in monozygotic (identical) and dizygotic (non‐identical) pairs, that have the potential to provide new information in the future. Current knowledge about the genetic bases of common dental problems is summarized and future directions in dental research involving twins are outlined.
Endodontic sequelae of dental erosion
Authors: Sivasithamparam K. , Harbrow D. , Vinczer E. , Young WG
Published: March 2008

Background: The incidence of pulp involvement in patients with excessive wear has not been extensively documented.

Methods: Clinical records of 448 patients with excessive tooth wear were reviewed and 52 cases (11.6 per cent) with near or frank pulp exposures or root canal treatments were found and their numbers and sites were tabulated. Light microscopy of study models was used to determine aetiology at each site of exposure as attrition, erosion or abrasion, scanning electron microscopy (SEM) was performed on some individual teeth.

Results: Forty sites of near exposure and 57 sites of frank exposures or root canal treatments were found, some cases had both types of exposure. The commonest sites exposed by erosion were the palatal surfaces of maxillary, and the incisal surfaces of mandibular anterior teeth. Posterior teeth were not commonly affected. Toothbrush abrasion had exacerbated some lesions as shown by SEM.

Conclusions: Endodontic sequelae were found in 11 per cent of tooth wear patients as late stages of dental erosion. Near and frank exposures of the pulp thus constitute a small but significant, problem for the Australian dental profession's concern in the management of the tooth wear cases.
Access to dental care by young South Australian adults
Authors: Roberts‐Thomson KF , Stewart JF
Published: March 2008

Background: Despite reported concern over the dental care of young adults little research has been done on their use of dental services in Australia. The aim of this study was to investigate the patterns of dental utilization of young South Australian adults aged 20–24 years.

Methods: A random sample of 2300 young adults was selected from the electoral roll. Partial or complete addresses and possible phone numbers were obtained for 1921 persons. Telephone interviews were conducted for 1261 subjects to obtain information on socio‐demographics, health behaviour and dental visiting (response rate 65.6 per cent).

Results: One third of young adults (34 per cent) had not made a dental visit in the previous two years and 38 per cent usually visited for a problem rather than a check‐up. Making a dental visit in the last two years was significantly associated with a number of socio‐demographic variables including age and gender, with holders of private dental insurance and those who have not avoided care because of cost having higher odds of making a visit and males and government concession card holders having lower odds of visiting. Usual reason for visiting a dentist for a problem was significantly associated with no private dental insurance, holding a government concession card, no tertiary education and avoiding care because of cost.

Conclusions: This study suggests that demographic and economic factors influenced use of dental services and reason for visiting of young South Australian adults.
Training for dentists in smoking cessation intervention
Authors: Trotter L. , Worcester P.
Published: March 2008

Background: Although dentists are ideally placed to deliver smoking cessation advice and assistance to their patients, smoking cessation interventions are not often incorporated as a routine part of dental care. Research is needed to identify factors that facilitate and inhibit dentists' capacities to deliver smoking cessation advice.

Methods: An initial focus group discussion was conducted in Melbourne with 10 dentists. Six Victorian country dentists were interviewed in depth by telephone. Following this qualitative data collection, a random sample of 250 dentists (response rate of 57 per cent) was interviewed by telephone. Dentists were asked about their perceived role, current practices, knowledge of resources and services and opinions on training in relation to smoking cessation.

Results: Dentists are willing to ask and advise patients about smoking, but are less inclined to assist patients to quit or arrange follow‐up. Dentists are more likely to implement one‐off, opportunistic interventions rather than take a systematic preventive approach. Dentists are interested in attending further education and say they require training to be relevant to the context of their day‐today running of the dental practice.

Conclusions: Training should aim to legitimize the dentist's role in smoking cessation and provide strategies and resources so that dentists can practise interventions as part of their day‐to‐day work.
A cleaning protocol for rotary nickel‐titanium endodontic instruments
Authors: Parashos P. , Linsuwanont P. , Messer HH
Published: March 2008

Background: The cleaning of endodontic and all dental instruments prior to sterilization is a prerequisite for their processing for re‐use. This study aimed to develop a clinically practical cleaning protocol for rotary nickel‐titanium (NiTi) endodontic files prior to sterilization.

Methods: Cleaning experiments were conducted on six different types of files that had been used on human teeth. The experiments involved three components of mechanical and chemical removal of root canal debris from the files: the use of sponges soaked with chlorhexidine to remove gross debris, pre‐soaking, and ultrasonication. After cleaning, the files were immersed in Van Gieson's solution and examined under magnification for stained debris. New unused files were also examined.

Results: Macroscopically, there were no instances of visible debris and all files appeared clean after all cleaning sequences. Microscopically, new files showed both stained and unstained debris, and several experimental cleaning regimens produced files that were free of stained debris. Combining elements of the most effective cleaning sequences resulted in a cleaning protocol that predictably produced clean files.

Conclusions: The results do not support the recommendation for the single use of endodontic files based on inability to clean files between uses. Under experimental conditions the cleaning protocol developed rendered rotary NiTi files 100 per cent free of stained debris. The protocol comprises 10 vigorous strokes in a scouring sponge soaked in 0.2 per cent chlorhexidine solution, a 30 minute pre‐soak in an enzymatic cleaning solution, 15 minutes ultrasonication in the same solution, and a 20 second rinse in running tap water. The protocol can be applied to all endodontic files.
Diagnostic comparison of three groups of examiners using visual and laser fluorescence methods to detect occlusal caries in vitro
Authors: Fung L. , Smales R. , Ngo H. , Mount G.
Published: March 2008

Background: To evaluate the accuracy of the DIAGNOdent laser device (DD) for detecting occlusal fissure caries when used by three groups of examiners.

Methods: Three final‐year dental students (S), three General Dental Practitioners (G), and three Academic Clinicians (A) individually examined the non‐cavitated occlusal surfaces of 25 extracted permanent molars using visual inspection (VI) then DD assessments. The presence of caries was confirmed following tooth sectioning. A cut‐off limit of 30 was used for the DD to avoid over‐treatment in a low caries‐risk situation.

Results: For VI, individual examiner sensitivity (caries correctly diagnosed) ranged from 53 to 86 per cent, and specificity (sound teeth correctly diagnosed) ranged from 76 to 95 per cent, with low Kappa agreements. Group S achieved the highest sensitivity (80 per cent) and Groups G and A achieved the highest specificities (88 per cent). For DD, individual examiner sensitivity ranged from 19 to 77 per cent, and specificity from 71 to 97 per cent, with generally moderate Kappa agreements. Group A achieved the highest (67 per cent) and Group G the lowest (44 per cent) sensitivities, and Group G achieved the highest specificity (94 per cent).

Conclusions: There were similar widely varying results for the two diagnostic methods and for the three groups of examiners. However, the relatively high sensitivities found with VI and specificities found with DD should avoid over‐treatment in low caries‐risk populations.
Adhesive restorative materials: A review
Authors: Tyas MJ , Burrow MF
Published: March 2008

‘Adhesive’ restorative dentistry originated with the work of Buonocore in 1955 in bonding resin to etched enamel. Since then, adhesive materials and techniques have developed at a rapid rate. The first chemically adhesive material (zinc polycarboxylate cement) was marketed in the late 1960s, and glass‐ionomer cements and dentine bonding agents have since become available.

This review focuses on the latter two products. Glass‐ionomer cements have a particular role in adhesive dentistry because of their reliable chemical adhesion to enamel and dentine, and because of their apparent ability to promote the remineralization of ‘affected’ dentine. Dentine bonding agents have undergone marked changes in presentation over the last 15 years, but all have an essentially similar bonding system, that of hybrid layer formation. However, the most recent systems have limited clinical data supporting their use.
Latex allergy in dentistry. Review and report of case presenting as a serious reaction to latex dental dam
Authors: Chin SM , Ferguson JW , Bajurnow T.
Published: March 2008

Latex allergy may have severe consequences including development of anaphylaxis. This report describes a patient who underwent a reaction to latex dental dam manifesting as erythema, facial swelling and mild airway compromise. Restorative procedures under latex dental dam were performed under local anaesthesia on two occasions resulting in reactions of increasing severity. Following the first event the cause of the reaction was undetermined, but attributed to a possible allergy to local anaesthetic, and managed with corticosteroids and antihistamines. On a subsequent occasion the swelling was more severe, associated with difficulty in swallowing and mild airway compromise, and was managed as previously with adrenaline also being required. Latex allergy was subsequently confirmed.
The potential for dental plaque to protect against erosion using an in vivo‐in vitro model — A pilot study
Authors: Cheung A. , Zid Z. , Hunt D. , McIntyre J.
Published: March 2008

Background: Tooth erosion is a problem for professional wine tasters (exogenous erosion from frequent exposure to wine acids) and for people with gastro oesophageal reflux disease (GORD) and bulimia who experience frequent reflux of gastric contents into the mouth (endogenous erosion from mainly HCl). The objective in this study was to determine whether plaque/pellicle could provide teeth with any protection from two common erosive acids, using an in vivo‐in vitro technique.

Methods: Tiles of human tooth enamel and root surfaces were prepared from six extracted, unerupted third molar teeth and sterilized. Mandibular stents were prepared for six volunteer subjects and the tiles bonded to the buccal flanges of these stents. They were worn initially for three days to permit a layer of pellicle and plaque to form over the tile surfaces, and for a further 10 days of experimentation. Following cleaning of the plaque/ pellicle layer from the tiles on the right side flange, all the tiles were submerged in either 0.06M HCl or white wine for an accumulated time of 600 and 1500 minutes, respectively. Depths of erosion were determined using light microscopy of sections of the enamel and root tiles. SEM of the lesion surfaces was carried out to investigate the nature of erosive damage and of plaque/pellicle remnants.

Results: Retained plaque was found to significantly inhibit dental erosion on enamel, from contact with both HCl and wine, compared with that resulting following its removal. However, it was found to provide no significant protection on root surfaces. SEM analysis of the tile surfaces revealed marked etching of enamel on the cleaned surfaces, and considerable alteration to the appearance of remaining plaque and pellicle on most surfaces.

Conclusion: Within the limitations of numbers of specimens, dental plaque/pellicle provided a significant level of protection to tooth enamel against dental erosion from simulated gastric acids and from white wine, using an in vivo‐in vitro model. It was unable to provide any significant protection to root surfaces from these erosive agents. Possible reasons for this difference are explored.
Uptake of rotary NiTi technology within Australia
Authors: Parashos P. , Messer HH
Published: March 2008

Background: Rotary NiTi technology was introduced into Australia approximately 10 years ago. Little information is available in the dental literature to explain the adoption of new technology in dentistry. The aim of this paper is to identify and describe demographic features in the uptake of rotary NiTi technology within Australia.

Methods: In 2001, a questionnaire survey was mailed to a stratified systematic sample of general dentists and endodontists in Australia. The numbers of dentists in each state adopting the new technology were recorded and the results tabulated and graphed.

Results: The response rate for the survey was 87 per cent. Overall, 26 per cent of responders used rotary NiTi instruments with a significantly higher proportion of endodontists (64 per cent) than general dentists (22 per cent). A significantly lower proportion of South Australian metropolitan general dentists used rotary NiTi compared with metropolitan dentists in all other states combined. The rate of uptake by South Australian dentists was lower than the other states. A significantly higher proportion of Queensland endodontists were using rotary NiTi compared with endodontists in New South Wales. A significantly greater proportion of rural dentists had tried and abandoned the new technology than metropolitan dentists.

Conclusions: The adoption of rotary NiTi in Australia appears to conform to diffusion of innovation theory and has reached a critical mass making it self‐sustaining.