bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical evaluation of the bond between composite resin and etched glass ionomer cement
Authors: Tyas M. J. , Toohey A. , Clark J.
Published: May 2009

One hundred and thirty‐eight non‐undercut Class V abrasion lesions were restored using glass ionomer cement overlaid by composite resin. Four techniques were used: enamel and glass ionomer acid‐etched, enamel only acid‐etched, ionomer only acid‐etched, and neither enamel nor glass ionomer acid‐etched. The restorations were examined after six months, one year and two years and evaluated for integrity and marginal staining, the latter employing a direct clinical method and a set of photographic standards. The relative failure of restorations at six months was maintained at subsequent time intervals, and at two years the failure incidence was 10, 35, 43 and 58 per cent for the above four techniques respectively. Marginal staining was most evident around those restorations for which only the glass ionomer had been etched. The results indicate that the retention of composite to etched glass ionomer is similar to that of composite to dentine using many dentine bonding agents. The several advantages of glass ionomers over dentine bonding agents are discussed.
Ameloblastic fibro‐odontoma. Case report
Authors: Günhan Ömer , Celasun Bülent
Published: May 2009

Ameloblastic fibro‐odontoma is a relatively rare odontogenic tumour which is composed of ameloblastic fibroma and a complex or compound odontoma. In this article, a case of a two‐year‐old boy with this tumour is presented.
The wettability of bonding resins used in the composite resin/glass ionomer ‘sandwich technique’*
Authors: Mount G. J.
Published: May 2009

There is some controversy about the significance of the wettability of the unfilled resin bonding agent that is generally recommended for prior application when placing a composite resin restoration. It has been suggested that the degree of viscosity does not matter. However, when investigating the union which is developed between composite resin and glass ionomer cement in the ‘sandwich technique’, it was noted that when using certain composite resins and their prescribed bonding resins the failure under tensile stress was adhesive at the union rather than cohesive in the cement. Further investigation showed that the bonding resins involved in these failures were more viscous than those bonding resins used in the more successful unions.

In this investigation the contact angle of the bonding resin on the surface of glass ionomer cement was used as the measure of viscosity. It is suggested that the degree of viscosity of the bonding resin is significant in the success or otherwise of the ‘sandwich technique’.
Requirement and supply of dental services in Victoria
Authors: Spencer A. John , Lewis Jenny M.
Published: May 2009

The appropriateness of dental manpower has become a great uncertainty in the changing practice of dentistry. This paper presents research on the requirement for and supply of dental services in Victoria between 1984 and 1996. The requirement for dental services was found to be increasing due to population growth and higher per capita demand due to decreased edentulism. The supply of dental services was found to be mildly decreasing due to balanced supplementation and attrition processes and subtle sex ratio and age distribution changes among dentists. The resulting market excess, even after consideration of idle capacity and transfer of services supplied to dental therapists, provides a marked contrast to many, but not all, developed countries. It also offers an opportunity to shape occupational and specialty distribution to the advantage of dental professions and the public.
Guidelines for the use of dietary fluoride supplements in Australia
Authors: Riordan Paul J.
Published: May 2009

A survey in 1988 of brands of fluoride supplements available in a non‐fluoridated town in Western Australia, and tablets described in pharmaceutical product registers, revealed that six brands of tablets and one brand of solution (drops) were on the market. Tablets contained 2.2 mg or 1.1 mg NaF; the solution contained 2.2 mg NaF per mL. All products provided age‐dose schedules which would give fluoride supplementation at levels greater than the National Health and Medical Research Council guidelines. In one case, infants following the schedule would receive four times the recommended dose for the first two years of life. Compliance with several of the age‐dose schedules would be certain to cause significant dental fluorosis. Whether the others caused fluorosis would depend on the quantity of fluoride in the diet, and consumption of fluoride toothpaste. The survey showed a generalized disregard on the part of the ethical pharmaceutical industry for the risk of dental fluorosis, and reveals a need for a voluntary, or legally enforced, code of conduct for manufacturers of fluoride supplements. The value of guidelines which are not monitored is doubtful.
Biological and clinical evaluation of the transmandibular implant
Authors: Arvier J. , Scott J. , Goss A. , Wilson D. , Tideman H.
Published: May 2009

The transmandibular implant has been shown to be a successful clinical solution to prosthetic rehabilitation of patients with gross mandibular atrophy. Aspects of the biocompatibility of the implant material including the component metals in the alloy have been tested in an animal model utilizing sheep. The initial Adelaide results in the clinical multicentre trial are presented. These were generally excellent and the reasons for the few failures are presented.
Attitudes of Victorian dentists to removable partial denture prosthodontics: treatment planning
Authors: Parker D. A. S. , Harcourt J. K. , Cheung N. H.
Published: May 2009

A survey of the attitudes of dentists in Victoria to various aspects of the treatment planning phase of removable partial denture prosthodontics was undertaken. Data were analysed and compared with those obtained from an identical study in South Australia. Those Victorian dentists who graduated in the 1960s, those who worked in multiple‐practitioner practices, or non‐rural areas, and those who had an added interest in removable prosthodontics were more likely to stress the importance of a greater number of attributes than those who graduated in the 1950s or 1970s, or those who worked alone, in rural areas, or had no particular interest in the discipline. Results indicated also that Victorian dentists tended to place greater emphasis on many of the concepts embraced by the questions asked than their interstate colleagues.

It is suggested that, in addition to formal education, intraprofessional relationships and interest in a discipline are factors which might influence the concepts and attitudes of general practitioners.
Keeping the pulp alive: the pharmacology and toxicology of agents applied to dentine
Authors: Hume W. R. , Massey W. L.
Published: May 2009

Abstract— Materials applied to teeth release chemicals which may diffuse through dentine to either harm or help the dental pulp. Chemical threats are minimized by material choice or by using relatively impermeable lining or base materials which are themselves of low chemical toxicity. The most probable long‐term threat to the pulp in the restored tooth is bacterial, through leakage around restorations. This may be prevented by the use of treatment sequences designed to develop an effective seal. Pulpal inflammation is treated primarily by removal of the irritant cause; inflammation may also be suppressed in the very short term by corticosteroids, and its resolution aided in the longer term by zinc oxide‐eugenol preparations.
Microbiological assays as predictors of the response to periodontal therapy
Authors: Newcomb G. M. , Nixon K. C.
Published: May 2009

Thirty‐four patients with periodontal disease each had subgingival plaque samples collected from four sites (one from each quadrant) in their mouths. The relative proportions of spirochaetes, motile rods and cocci were determined using dark field microscopy and the proportion of anaerobic to aerobic microorganisms was calculated after culture. In addition, clinical recordings were made at these sampled sites. The patients then underwent a course of periodontal treatment and were placed on a maintenance programme. The clinical recordings were repeated and the results examined to ascertain if the original microbiological or clinical measurements could have been used to predict the response to therapy.

Of the baseline recordings, the initial probing depth, the initial attachment level and the presence of suppuration all showed a positive correlation with the degree of pocket reduction or attachment gain produced by treatment. The percentage of cocci in the subgingival plaque correlated negatively with the treatment response. Suppuration seemed to be associated primarily with the original pocket depth while the percentage of cocci in subgingival plaque showed a true relationship with the amount of attachment gained after periodontal therapy. The significance of this finding is discussed.
The palatal radicular groove. Two case reports
Authors: Mayne John R. , Martin Ian G.
Published: May 2009

Two cases of the rare anomaly, the palatal radicular groove, affecting maxillary lateral incisors, are reported and discussed. Both were considered to be untreatable. Horizontal sections of one of these cases demonstrated a canal configuration not previously reported.
Clinical performance of dentine bonding agents in the enamel‐etched Class V abrasion lesion
Authors: Tyas Martin J.
Published: May 2009

Ninety‐three non‐undercut cervical abrasion lesions were restored with one of five dentine bonding agents and composite resin, using enamel etching to supplement retention. The restorations were reviewed at approximately one, six, 12 and 24 months. The loss rate at one year ranged from zero to 50 per cent, and marginal staining became apparent over the one‐year period. It is evident that even with enamel etching, some dentine bonding agents are not effective enough to reliably retain composite in Class V abrasion lesions.
The use of theatre in dental health education
Authors: Bourke L. F.
Published: May 2009

This report describes the use of theatre as a strategy for school dental health education. A play with messages relating to dental disease and its prevention was staged by school dental personnel for middle level primary schoolchildren. Feedback from the school staff indicated that the performance was well received and understood by the majority of the pupils. School dental personnel found that the awareness of dental disease and its prevention among their patients was generally more positive after the play. It thus appears that theatre is a useful medium for dental health education of young people.
Visualization of the maxillary sinus and styloid processes using rotational panoramic radiography
Authors: Monsour P. A. , Mendoza A. R.
Published: May 2009

A technique is presented which improves visualization of the medio‐lateral aspect of the maxillary sinus using rotational panoramic radiography. The method was also assessed for accuracy of styloid process projection. Using a specially constructed Perspex stand, dried skulls of varying ages were radiographed in various reproducible positions using a panoramic unit. The best medio‐lateral view of the maxillary sinus of adult skulls was achieved by: (1) raising the height of the film approximately 20 mm in relation to the subject; (2) moving the subject 15–20 mm forward of the standard position for a panoramic view for adults (10–15 mm for children); and (3) tilting the occlusal plane downwards approximately 8–10 degrees. The styloid processes were readily seen using this maxillary sinus view. The resultant image of the process was elongated by a factor of 1.24 +0.02 by this technique.
‘A bridge too far …’. Case report
Authors: Loh H. S. , Rauff A.
Published: May 2009

An elderly man was assaulted and sustained facial injuries with fractures of the mandible and left zygoma. An unusual complication of aspiration of an intact four‐unit metal bridge is reported. Immediate retrieval was done under general anaesthesia by rigid bronchoscopy. The technique is described. The importance of careful clinical and radiographic examination is stressed.
Mandibular osteomyelitis and pathologic fracture associated with metabolic catabolism induced by ‘binge’ drinking. Case report
Authors: Ferguson John W. , Luyk Neil H. , Whitley Brian D.
Published: May 2009

A case is reported where intermittent ‘binge’ drinking was associated with mandibular infection, pathologic fracture and failure of healing in a 30‐year‐old man.
A large dermoid cyst of the neck. Case report
Authors: Young B. K. , Davies A. S.
Published: May 2009

An elderly patient presented with a large asymptomatic submental swelling which had been present for about fifteen years. The clinical diagnosis was a dermoid cyst and the lesion was removed in toto. Histological examination confirmed the clinical diagnosis. Unless such lesions are very large and cause displacement of the tongue, there is usually no associated dyspnoea, dysphagia or dysphonia.
Comparison of dental needs with the treatments actually received
Authors: Broughton Alan M. , Smales Roger J.
Published: May 2009

The main purpose of the study was to determine the types, causes, dental needs, and follow‐up treatments of the chief complaints of a socio‐economically disadvantaged population of patients attending a public dental hospital.

Around half of the 301 patients examined were 45 years of age and older, and the vast majority were of caucasian origin. The most common dental complaints in 259 patients were toothache, broken teeth, lost fillings, and painful, broken or loose dentures. The most frequent causes of the chief complaints were judged to be dental caries, and inadequate restorations and removable prostheses. On examination, most of the patients also had one or more other unsatisfactory restorations or removable prostheses, especially in the 35 years and over age group. Deep periodontal pockets were also found most often in this age group.

After four to six months, of the 259 patients with chief complaints, 113 had had their complaints treated and 45 had not, 47 patients were given a different form of treatment from that proposed, while 31 treatments were uncompleted, and 23 patients could not be followed up.
The effects of temperature on the setting of glass ionomer (polyalkenoate) cements
Authors: Fricker John , Hirota Kazuo , Tamiya Yoriyuki
Published: May 2009

Glass ionomer (polyalkenoate) cements have proved to be superior to zinc phosphate cements as orthodontic luting agents.

Setting behaviours at different temperatures were recorded by an oscillating rheometer under controlled conditions. The working time of these cements can be increased by mixing on a chilled glass slab with setting time at mouth temperatures remaining rapid. Where more than one orthodontic band is cemented per mix, the authors recommend refrigeration of the glass slab for at least one hour prior to mixing the cement.
An overview of industrial accidents with particular reference to facial trauma
Authors: Shalhoub S. Y.
Published: May 2009

As an integral part of the economy of Saudi Arabia the industrial sector has rapidly developed in the last decade and is still open for more growth. Thus, there is likely to be an increase in industrial accidents, often with added consequences for the medical services. Because of this, cumulative information on industrial accidents is needed. This paper reports on industrial accidents in order to alert medical researchers to the need for specific studies of different industrial occupations in Saudi Arabia so that adequate administrative and medical services may be available should an industrial accident occur.
Complications associated with maxillary nerve block anaesthesia via the greater palatine canal
Authors: Sved Anthony M. , Wong John D. , Donkor Peter , Horan James , Rix Leesa , Curtin Justin , Vickers Russell
Published: May 2009

This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.
An investigation of the composite resin/porcelain interface*
Authors: Lu Raymond , Harcourt John K. , Tyas Martin J. , Alexander Babs
Published: May 2009

Failures at composite resin/porcelain interfaces under shear‐like loading were examined. Porcelain surfaces were treated with hydrofluoric acid and/or one of two silane coupling agents, using two different composite resin cements.

The results showed that after seven days storage, bond strengths of specimens which had undergone porcelain surface treatment were greater than the cohesive strength of the porcelain itself, resulting in brittle fracture of the porcelain. The diluted restorative composite resin performed as well as the commercial composite resin cement. Silane pre‐treatment of porcelain was important as the bond strength of etched/silane primed specimens was significantly higher than the etched only specimens. However, one primer appeared to be more efficient than the other in bond promotion. Some explanations for the differences in bond strengths are offered.
The effect of chronic fluoride administration on rat condylar cartilage
Authors: Harbrow D. J. , Robinson M. G. , Monsour P. A.
Published: May 2009

Morphometrical and histochemical techniques were used to demonstrate changes to the cartilage layer of the rat temporomandibular joint condyle following chronic exposure to fluoride. An increase in thickness of the cartilage layer was noted in rats given 100 parts per million sodium fluoride in drinking water. No significant changes were observed with either control or low dose (10 parts per million) groups. The observed thickening was attributable to an increase in number and size of cells of the lower hypertrophic zone. Accumulations of glycogen were observed in these cells, which reflects the inhibitory effect of fluoride on glycolysis. Stimulation of chrondrocytes by fluoride may have delayed the normal prooesses of capillary invasion, resulting in thickening of the cartilage layer. No changes to staining patterns of immature or mature types of collagen were observed, nor did the staining pattern of detectable glycosaminoglycans change due to fluoride.
Response of the oral tissues to prolonged uninterrupted coverage by a removable partial denture. Case report
Authors: Ogunbodede Eyitope O. , Ojo Michael A. , Otuyemi Donald O. , Hollist Nestor O.
Published: May 2009

Abstract— The response of hard and soft oral tissues to prolonged uninterrupted wearing of a removable partial prosthesis in a Nigerian patient is discussed. To our knowledge only one case has been reported in the literature. In this case additional mucosal changes to the reported caries‐free pattern is discussed.
Denture stomatitis — a review of the aetiology, diagnosis and management
Authors: Jeganathan S. , Lin Chew Chong
Published: May 2009

Abstract— Denture stomatitis is a common recurring problem of the denture wearers. The aetiology of the disease includes infection, trauma and probably a defect in the host defence mechanism. Current thinking suggests an interplay of most of these factors in the pathogenesis of the disease. The extent of interplay of these factors is still a controversy. Candida albicans has been implicated as the causative organism. However, in the light of recent research it is debatable if it is the only causative organism. Recently, cases resistant to antifungal therapy have been reported. In such cases other micro‐organisms have been isolated. At the moment, comprehensive management includes meticulous denture hygiene together with anti‐fungal or antibacterial therapy and correction of denture faults.
Modulation of human neutrophil adherence by oral bacteria
Authors: Seow W. K. , Whitman L. M. , Bird P. S. , Thong Y. H.
Published: May 2009

Abstract— Polymorphonuclear neutrophils (PMNs) comprise over 90 per cent of leukocytes in the oral cavity. Although these phagocytic ceils have primary defence roles in the gingiva, their stimulation by micro‐organisms may also cause substantial tissue damage due to the release of lysosomal enzymes and oxygen radicals. Adherence of PMNs to the endothelium and their subsequent diapedesis and egress to areas of infection are considered early vital events in the inflammatory process. In this study, oral bacteria were screened to determine their direct effects on PMN activation using an in vitro method of measuring PMN adherence to Dacron fibres. Most of the bacteria investigated increased PMN adherence, indicating their potential to cause tissue damage through the release of PMN lysosomal enzymes and other products. In contrast, Bacteroides species suppressed PMNs, indicating their ability to circumvent the phagocytic cells, thus gaining a potential advantage in dental colonization. The modulatory effects of oral bacteria on PMN activation may have significant roles in the immunopathogenesis of oral disease.
Dental treatment and dental health. Part 1. A review of studies in support of a philosophy of Minimum Intervention Dentistry
Authors: Dawson A. S. , Makinson O. F.
Published: May 2009

Abstract— An international movement emerged in 1986–1987 which heralded a major change in the role of conservative dentistry. This shift was away from the traditional operative dentistry, with its relatively frequent replacement of restorations, to a concept of ‘Minimum Intervention Dentistry’, which advocates the use of adhesive dental materials, remineralization techniques and monitoring of initial carious lesions. The move away from some of Black's concepts started as investigations examined the dental health of patients in the National Health Service of Great Britain. These investigations, and the report of the Committee of Enquiry into Unnecessary Dental Treatment, have resulted in an extensive re‐education programme being initiated by the British Department of Health and Social Security in conjunction with the British Dental Association.

This paper, and a subsequent one, were written to enable widespread dissemination of these ideologies to Australian practitioners. While they may appear provocative to some, these papers were merely meant to stimulate discussion on the implications of this research for dentistry in this country. In this paper the results from the British investigations are presented, as is a discussion of some of the outcomes of this and other related research.
Some parameters for testing deformation of elastomeric impression materials
Authors: Blomberg P. A. H. , Mahmood S. , Smales R. J. , Makinson O. F.
Published: May 2009

Because of conflicting published data, the temperature rise in four elastomeric materials was measured with a thermistor during setting in the oral cavity and in metal and plastic moulds of varying shapes and volumes for ‘elastic set’ specimens. The clinical temperature rise was 2–3°C higher in the molar region than anteriorly, except for the polysiloxane. The temperature range attained in the set materials varied from 29°C to nearly 35°C for clinical and in vitro specimens.

The average time taken by a group of operators to remove this type of impression from the mouth was five seconds. In a custom tray with light and heavy viscosity materials, the syringe material layer was only 0–0.15 mm thick and, essentially, the heavy viscosity material provided the elastic components for the impression.
Acrylic resins reinforced with woven highly drawn linear polyethylene fibres. 2. Water sorption and clinical trials
Authors: Chow T. W. , Ladizesky N. H. , Clarke D. A.
Published: May 2009

The results reported in this paper are part of a continuing study of the reinforcement of acrylic denture base resins with highly drawn linear polyethylene fibres. Water sorption is significantly reduced by incorporation of these fibres, even though the water diffusion processes as such remain broadly unaffected. Clinical trials are encouraging and the reinforced dentures have been well accepted by all the patients.
The adaptation achieved by four root canal filling techniques as assessed by three methods
Authors: Amditis Constantine , Bladder Stephen M. , Bryant Roland W. , Hewitt George H.
Published: May 2009

Four root canal filling techniques — lateral condensation, McSpadden compaction, ultrasonic activation (Enac), and thermoplastic injection (Ultrafil) — were assessed for adaptation of the filling material to the canal wall. The adaptation and leakage were examined quantitatively using an electrochemical method and a linear dye penetration method, and qualitatively by radiographic evaluation. Using the electrochemical method, differences among obturation techniques were relatively small, although a greater proportion of the teeth that had been filled by lateral condensation exhibited no leakage. Radiographically, the techniques appeared to exhibit similar adaptation in the apical 6 mm. The techniques of lateral condensation and ultrasonic activation showed superior control of length of the root canal filling.
Multiple bilateral dens in dente involving all the premolars. Case report
Authors: Karaca İnci , Toller Melahat Öġütcen
Published: May 2009

Dens in dente, also known as dens invaginatus, dilated composite odontoma or deep foramen caecum, is a developmental malformation which usually affects maxillary incisor teeth, particularly lateral incisors. It may occur, however, in teeth anywhere within the jaws but other locations are comparatively rare. It can occur within both the crown and the root, although crown invaginations are more common. In this paper a case of multiple bilateral dens in dente involving maxillary and mandibular premolars is presented.
Totally submerged deciduous maxillary molars. Case reports
Authors: Antoniades K. , Tsodoulos S. , Karakasis D.
Published: May 2009

The total reimpaction or submersion of deciduous teeth is a very uncommon phenomenon and few cases have been reported in the literature. The condition affects the mandibular second deciduous molar most often and the maxillary first deciduous molar least often. Two cases of totally reimpacted maxillary deciduous molars are reported
Malocclusion prevalence in an ethnic Chinese population
Authors: Lew K. K. , Foong W. C. , Loh E.
Published: May 2009

Population norms derived from one ethnic group may not necessarily be valid and accurate for other ethnic groups. With the increasing number of ethnic Chinese immigrants in Australia, Europe, and America, it would be useful for dental practitioners to be informed about malocclusion prevalence among Chinese. This study was carried out on 1050 Chinese school children (aged 12–14 years) to assess both qualitatively and quantitatively certain occlusal features. The population was found to have a high incidence of Class III malocclusions compared with Caucasians. However, the incidence of Class II malocclusions was quite similar to those reported in Caucasians. Normal occlusions occurred in about 7 per cent of this population. Although this percentage was much lower than those reported in blacks, it was similar to those reported in Caucasians. Crowding occurred in about 50 per cent of cases, which was slightly less than for those reported for Caucasians. Increased overbites were also less common in this Chinese population compared with Caucasians. Compared with Caucasians, cross‐bites were also less frequent in this Chinese population.
Developmental disturbances of permanent teeth following trauma to the primary dentition
Authors: von Arx Thomas
Published: May 2009

The topographic relationship of the apices of the primary teeth to the permanent tooth germs explains the potential for possible developmental disturbances of the permanent teeth after injuries to their predecessors. The anatomical, histologic and clinical aspects of permanent tooth malformation following trauma to the primary teeth are described. One hundred and fourteen children with originally 255 traumatized primary teeth have been re‐examined (with an average period of 5.1 years after the trauma) to assess any developmental disturbances of the corresponding permanent teeth. Twenty‐three per cent of partially or completely erupted permanent teeth showed developmental disturbances. The most frequent malformation was enamel hypoplasia including enamel discoloration and/or enamel defects. The highest prevalence of developmental disturbances of permanent teeth was found after intrusive injuries of primary teeth.
The effect of post adaptation in the root canal on retention of posts cemented with various cements
Authors: Chan Frank W. , Harcourt John K. , Brockhurst Peter J.
Published: May 2009

This laboratory study compared the retention of prefabricated posts in well‐fitting and loose‐fitting post canals using different cement materials. Eighty‐three human teeth were prepared for post placement. One of zinc phosphate cement, polycarboxylate cement, glass ionomer cement or resin cement was used to cement each post in place. A tensile force was applied to remove each post and the separation force was recorded. Posts cemented with the resin cement were the most difficult to dislodge. Posts cemented into loose‐fitting canals exhibited greater resistance to dislodgement than posts cemented into well‐fitting canals irrespective of the type of cements used.
A retrospective clinical evaluation of resin‐bonded bridges inserted at the Adelaide Dental Hospital
Authors: Berekally T. L. , Smales R. J.
Published: May 2009

The clinical performance of resin‐bonded Rochette and Maryland bridges inserted by various operators at the Adelaide Dental Hospital is reported. Thirty‐four Rochette bridges (30 anterior, 4 posterior) and 228 Maryland bridges (150 anterior, 78 posterior) were assessed. Clinical data were compiled on types of bridge failure, factors influencing bridge retention, and the effects of the prostheses on abutment teeth and supporting tissues. The failure rate for Rochette bridges over 6 years was 75 per cent with a median survival of 2.14 years. Debonding occurred in 70 per cent of bridge failures. The failure rate for Maryland bridges over 5 years was 42 per cent with a median survival of 2.60 years. Pontic fracture (29 per cent) and debonding (20 per cent) were the main failures observed. Porcelain pontics performed significantly better than the processed hybrid resin pontics (P<0.01). The main reasons for debonding included occlusal stresses, non‐retentive bridge designs and resin cement failure. A life‐table analysis showed no significant difference in the overall cumulative survival rates between Rochette and Maryland bridges. Bridge design and the choice of pontic material and resin cement emerged as significant factors influencing the success rate of the bridges examined.
A clinical evaluation of posterior composite resin restorations
Authors: Bryant Roland W. , Hodge Kerri‐Lea V.
Published: May 2009

There is a trend towards manufacturers seeking to provide dentists with a single, all‐purpose composite resin, usually of the small particle hybrid type. This three‐year clinical study compared the clinical performance of three different types of composite resin used in posterior teeth and identified several modes of failure. Of the 330 restorations (three composite resins and one amalgam control) initially placed in 72 patients, 223 restorations in 48 patients were available for evaluation at three years. Modified clinical criteria for assessing the restorations were able to discriminate among the composite resins. A microfilled composite and a small particle hybrid exhibited increasing evidence of marginal fracture (crevice) with time. In addition, the small particle hybrid showed evidence of wear at the margins more frequently than the other materials. Of the restorations available for assessment, four restorations of each of these two types of composite resin required replacement during the study. Coarse particle hybrid restorations showed evidence of wear but little evidence of marginal fracture.
Single tooth replacement—expanded treatment options
Authors: Chan Richard W. , Tseng Thomas N.
Published: May 2009

The aim of any prosthesis is to restore function and aesthetics by replacing the missing tooth with minimal risks to adjacent tissues. The options presently available to the patient for the replacement of a missing single tooth include the removable partial denture, partial and full coverage bridgework, resin‐bonded bridgework and the single‐tooth implant prosthesis. The relative merits and guidelines for successful application of these treatment modalities are presented.
Delayed calcification and congenitally missing teeth. Case report
Authors: Üner Oktay , Yücel‐Eroğlu Emel , Karaca Inci
Published: May 2009

A case of delayed differentiation and/or calcification, that is, development, followed by accelerated growth of the maxillary second premolars is presented. This condition was accompanied by the congenital absence of mandibular second premolars even though maxillary and mandibular third molar germs were present. The case was followed over a five‐year period. It seems that agenesis of any tooth might be found in conjunction with delay in development of any other tooth. Moreover, full development of a tooth germ (followed by an accelerated growth) as well as pathological changes may occur, despite an initial marked delay in tooth development.
Scope of oral and maxillofacial surgery: The psychosocial dimensions of orthognathic surgery
Authors: Shalhoub S. Y.
Published: May 2009

A group of 20 patients (12 females and 8 males) who underwent orthognathic surgery during the previous three years were surveyed. The reasons which determined the decision to undergo surgery are discussed. Patient satisfaction and the effect of surgery on psychological and social attitudes are explored.
Conservative management of erosion‐abrasion: A system for the general practitioner
Authors: Bevenius Joan , Evans Stanley , L'Estrange Peter
Published: May 2009

This final article in a series of three covering general practice aspects of erosion‐abrasion presents a three‐phase system for clinical management of erosive‐abrasive damage. The first phase comprises pre‐restorative case evaluation, initial measures to control factors predisposing to continued erosion‐abrasion and where necessary the provision of acrylic overlays to restore facial height. In the second phase the teeth are systematically restored using an acid‐etch composite resin technique; guidance for comfortable occlusion is provided by the patient acceptance method. The third phase comprises follow‐up, including monitoring of salivary and bacteriological parameters, maintenance of the restorations and modifications of preventive measures necessary to preserve the dentition restored by multiple composite therapy. Modern oral physiological concepts and recent developments in multiple composite therapy and erosion control are discussed.
A new approach for accurate pre‐planned occlusal adjustment
Authors: Au Anthony R. , Klineberg Iven J.
Published: May 2009

Occlusal adjustment is important in prosthodontic pre‐treatment procedures and in the management of some cases of craniomandibular disorders. This may involve tooth surface reduction and tooth surface addition with an appropriate restorative material. Occlusal adjustment must be distinguished from occlusal equilibration and selective grinding with clear indications and aims. A systematic preclinical and clinical protocol has clear advantages and the use of a thermoplastic vacuum‐formed template greatly increases the clinical accuracy of a pre‐planned adjustment.
Alterations in blood pressure and pulse rate in exodontia patients*
Authors: Paramaesvaran Mayuri , Kingon A. M.
Published: May 2009

The measurement of blood pressure and pulse rate prior to, during and after exodontia was conducted on 60 healthy patients. The aims were to first, investigate the changes in blood pressure and pulse rate, and second, to observe the presence of any clinically significant change over time. Thirty patients attending an Oral Medicine Clinic were used as the control group to allow a comparison to be made between the effects of exodontia and non‐invasive treatment. The results suggested that exodontia was the most stressful part of the procedure. Bradycardia during local analgesia was also noted. These changes in the cardiovascular parameters may represent a risk to patients with heart diseases especially those previously undiagnosed. Further, the results indicate the effect stress can have on the cardiovascular system and the importance of eliminating pain and minimizing patient anxiety.
Familial hemifacial microsomia due to autosomal dominant inheritance. Case reports
Authors: Singer Steven L. , Haan Eric , Slee Jennie , Goldblatt Jack
Published: May 2009

Hemifacial microsomia is a rare dentofacial anomaly which is regarded as a separate entity to Goldenhar syndrome and primarily affects the structures of the first branchial arch. It has a heterogeneous aetiology and tends to occur sporadically, though positive family histories have been reported. This paper reports on individuals in two generations of a family that has overlapping features of hemifacial micro‐somia and Goldenhar syndrome segregating as an autosomal dominant condition.
Exfoliative cytology in clinical oral pathology
Authors: Sugerman Philip B. , Savage Neil W.
Published: May 2009

Exfoliative cytology is a rapid, non‐invasive procedure for assessing dysplastic change within the oral epithelium. The indications for oral exfoliative cytology are reviewed and a technique for cell collection and smear examination is presented. The value of exfoliative cytology in oral cancer screening programmes as a public health measure is discussed.
Studies of the inflammatory process and malignant potential of oral mucosal lichen planus
Authors: Kilpi Anu , Rich Alison M. , Reade Peter C. , Konttinen Yrjö T.
Published: May 2009

Oral mucosal lichen planus (OMLP) is a well recognized mucosal disease with unknown aetiology. Considerable controversy exists as to whether OMLP is intrinsically premalignant, or if the disorder facilitates the development of oral mucosal squamous cell carcinoma (OMSCC) by external factors.

The aim of the present studies was to investigate the expression of c‐erbB‐2 protein in the keratinocytes of the initial biopsies of oral mucosal disorders diagnosed as OMLP with no evidence of epithelial dysplasia and to compare the results with the expression of c‐erbB‐2 protein in subsequent biopsies obtained from the same patients. These results were compared with the findings from another 26 biopsies from patiente with OMLP and control groups (patiente with dysplasia with no evidence of OMLP, patients with OMSCC with no evidence of OMLP and normal oral mucosa).

The expression of the c‐erbB‐2 protein was evaluated by Immunohistochemical staining of the gene product with the avidin‐biotin‐complex method using both fresh frozen and paraffin‐embedded tissue sections.

Five of the initial biopsies from patients with OMLP expressed the c‐erbB‐2 protein and one did not. None of the OMLP cases that subsequently showed evidence of dysplasia expressed the c‐erbB‐2 protein and of the OMSCC specimens from the patients with OMLP, 2 were negative and 1 expressed c‐erbB‐2 protein. Within the other group of OMLP specimens 3 (3/26) were negative for c‐erbB‐2 staining. The specimens from the control groups all expressed the c‐erbB‐2 protein.

The results indicated the probability of the absence of c‐erbB‐2 staining being an indication of a potential for neoplastic transformation in OMLP with dysplastic changes.
Establishment of peripheral blood and gingival T lymphocyte clones responsive to Porphyromonas gingivalis
Authors: Gemmell E. , Bartold P. M. , Seymour G. J.
Published: May 2009

T cells are central to the immune response to infection and studies have indicated a local immunoregulatory imbalance may exist in human periodontal disease. Since Porphyromonas gingivalis is generally recognized as a major periodontopathogen, the aim of this study was to establish T cell lines and clones specific to P. gingivalis from the gingival tissues and peripheral blood of P. gingivalis — infected subjects. Two subjects were selected from two groups of individuals (one from each group) established on the basis of P. gingivalis in their plaque and the presence of serum antibodies which react with P. gingivalis antigens. The two groups differed however in their clinical susceptibility (adult periodontitis) or resistance (gingivitis) to periodontal breakdown. The mean ages ± standard error of the mean of the two groups were 47.9 ± 2.2 and 49.6 ± 3.7, respectively, so that resistance in the gingivitis group was related to the age of the subjects. T cell lines and clones were established from the peripheral blood of one patient from each of the two groups and also from the gingival tissues of the same periodontitis subject. This study has demonstrated the capability of establishing P. gingivalis‐specific T cell lines and clones from P. gingivalis‐infected subjects and FACS analysis of the T cell receptor variable regions demonstrated that the clones were indeed monoclonal. The CD4:CD8 ratios of the peripheral blood‐derived T cell lines were 1.2 and 0.4 for the gingivitis‐derived line and the periodontitis‐derived line, respectively, thus supporting the clinical differences displayed by the two subjects.
The effect of endodontic access cavity preparation and subsequent restorative procedures on molar crown retention
Authors: Mulvay Paul G. , Abbott Paul V.
Published: May 2009

Preparation of an endodontic access cavity through a full crown may affect its retention. This study was undertaken to investigate the effects on molar crown retention of endodontic access cavities and their subsequent restoration. Thirty human molars were mounted in resin, crown preparations were cut and their surface areas were determined. Vented metal copings were cemented with zinc phosphate and the forces required to displace each coping were measured using a tensile‐testing machine. The copings were recemented, access cavities were cut and their surface areas determined prior to the displacement forces being re‐measured. The copings were recemented, assigned to two groups, and the access cavities were restored ‐ Group 1 with amalgam; Group 2 with glass ionomer (GIC). Displacement forces were re‐measured and the copings were recemented. The occlusal margins of the access cavities were ***bevelled and restored again prior to displacement forces being re‐measured. Mean displacement forces were ‐Group 1: Original (kg force), 37.86 ± 3.97; After access cavity, 29.28 ± 3.22; Amalgam, 50.21 ± 4.71; Amalgam + bevel, 46.45 ± 6.21. Group 2: Original, 42.77 ± 4.49; After access cavity, 39.25 ± 5.91; GIC, 48.11 ± 3.55; GIC + bevel, 39.63 ± 5.31. Statistical analyses with paired t tests showed that retentive values with access cavities were significantly lower than with intact crowns. Amalgam or GIC restorations increased retention beyond original values, significantly with amalgam. Bevelled occlusal margins decreased retention of crowns with restored access cavities but this was not significantly different from the original values. A significant relationship existed between total surface areas of the crown preparations, areas of the occlusal tables, and retentive values for crowns without access cavities. The access cavity area, as a proportion of the total area of the preparation, was related to the decrease in retention.
Heat Transfer and Effectiveness on Film Cooled Turbine Blade Tip Models
Authors: Kim Y. W. , Metzger D. E.
Published: May 2009

In unshrouded axial turbine stages, a small but generally unavoidable clearance between the blade tips and the stationary outer seal allows a clearance gap leakage flow to be driven across the blade tip by the pressure-to-suction side pressure difference. In modern high-temperature machines, the turbine blade tips are often a region prone to early failure because of the presence of hot gases in the gap and the resultant added convection heating that must be counteracted by active blade cooling. The blade tip region, particularly near the trailing edge, is often very difficult to cool adequately with blade internal coolant flow, and film cooling injection directly onto the blade tip region can be used in an attempt to reduce the heat transfer rates directly from the hot clearance flow to the blade tip. An experimental program has been designed and conducted to model and measure the effects of film coolant injection on convection heat transfer to turbine blade tips. The modeling approach follows earlier work that found the leakage flow to be mainly a pressure-driven flow related strongly to the airfoil pressure loading distribution and only weakly, if at all, to the relative motion between blade tip and shroud. In the present work the clearance gap and blade tip region is thus modeled in stationary form with primary flow supplied to a narrow channel simulating the clearance gap above a plane blade tip. Secondary film flow is supplied to the tip surface through a line array of discrete normal injection holes near the upstream or pressure side. Both heat transfer and effectiveness are determined locally over the test surface downstream of injection through the use of thin liquid crystal coatings and a computer vision system over an extensive test matrix of clearance heights, clearance flow Reynolds numbers, and film flow rates. The results of the study indicate that film injection near the pressure-side corner on plane turbine blade tips can provide significant protection from convection heat transfer to the tip from the hot clearance gap leakage flow.
An Advanced Method of Processing Liquid Crystal Video Signals From Transient Heat Transfer Experiments
Authors: Wang Z. , Ireland P. T. , Jones T. V.
Published: May 2009

A new method of processing the liquid crystal color change data obtained from transient heat transfer experiments is presented. The approach uses the full-intensity history recorded during an experiment to obtain an accurate measurement of the surface heat transfer coefficient at selected pixels. Results are presented for a model of a turbine blade cooling passage with combined ribs and film cooling holes. The implementation of the technique and the advantages to be gained from its application are discussed.
A Numerical Simulation of a Brush Seal Section and Some Experimental Results
Authors: Braun M. J. , Kudriavtsev V. V.
Published: May 2009

The brush seal technology represents quite a promising advance in the effort of construction of more efficient, and possibly smaller size engines. Conclusions of recent workshops determined that while the brush seal works well, there is a need to improve its performance characteristics. The considerable amount of experimental work performed to date has indicated the importance of the local flow phenomena in the global sealing process performance of the brush (Braun et al., 1990a, 1991b, 1992; Hendricks et al., 1991a). The distributed flow and pressure fields are thus of vital importance for the prediction of the possible sudden failure of the brush seal under unexpected local “pressure hikes.” It is in this context that the authors developed a numerical, two-dimensional time accurate dependent formulation of the Navier–Stokes equations with constant properties, and included the effects of inertia, viscous, and pressure terms. The algorithm is applied to a set of noncompliant multirow, multicolumn pin configurations that are similar to the ones found in an idealized brush seal configuration. While the numerical parametric investigation aims at establishing the occurrence of major flow patterns and associated pressure maps, the experimental portion of the paper is aimed at gaining further insight into the relevant flow structures, and thus guiding the development of the mathematical and numerical models.