Showing papers in "Australian Dental Journal in 1997"
TL;DR: The biological basis of LLLT is provided, areas of controversy where there is a pressing need for further research are identified and the findings of controlled clinical studies of the use of L LLT for specific soft tissue applications in dentistry are summarized.
Abstract: Despite more than 30 years of experience with low level laser therapy (LLLT) or 'biostimulation' in dentistry, concerns remain as to its effectiveness as a treatment modality. Controlled clinical studies have demonstrated that while LLLT is effective for some specific applications, it is not a panacea. This paper provides an outline of the biological basis of LLLT and summarizes the findings of controlled clinical studies of the use of LLLT for specific soft tissue applications in dentistry. Areas of controversy where there is a pressing need for further research are identified.
346 citations
TL;DR: A review of the literature relating to supernumerary teeth is presented along with four case reports to illustrate some possible presentations, diagnostic features, and treatment options.
Abstract: A review of the literature relating to supernumerary teeth is presented along with four case reports to illustrate some possible presentations, diagnostic features, and treatment options.
230 citations
TL;DR: In contrast to studies suggesting that rugae move forward with age, the majority of Aboriginal rugae that changed direction moved posteriorly, and there was a statistically significant association between rugae forms and ethnicity, straight forms being more common in Caucasians whereas wavy forms were more common Aborigines.
Abstract: The purpose of this study was to determine whether rugae patterns change with age and to compare the number and pattern of rugae in Australian Aborigines with those of Caucasians. For the longitudinal part of the study, serial dental casts of ten Aborigines, from 6 to 20 years of age, were examined and rugae patterns were recorded. To enable comparisons to be made between different ethnic groups an additional 100 dental casts of Australian Aborigines and 200 casts of caucasians, ranging in age from 13 to 17 years, were examined. Characteristics observed were number, length, shape, direction and unification of rugae. The length of rugae increased significantly with age but the total number of rugae remained constant. Thirty-two per cent of rugae showed changes in shape, while 28 per cent displayed a change in orientation. In contrast to studies suggesting that rugae move forward with age, the majority of Aboriginal rugae that changed direction moved posteriorly. Changes in rugae patterns have been assumed to result from palatal growth but alterations in pattern were observed in the Aboriginal sample even after palatal growth had ceased. The mean number of primary rugae in Aborigines was higher than in Caucasians, although more primary rugae in Caucasians exceeded 10 mm in length than in Aborigines. The most common shapes in both ethnic groups were wavy and curved forms, whereas straight and circular types were least common. There was a statistically significant association between rugae forms and ethnicity, straight forms being more common in Caucasians whereas wavy forms were more common Aborigines.
209 citations
TL;DR: The results support the findings of previous studies conducted overseas but additional information about musculoskeletal symptoms in this occupational group has been identified.
Abstract: This study describes the prevalence and distribution of symptoms of musculoskeletal disorders occurring in New South Wales dentists and investigates the relationship between these symptoms and work practices. Four hundred and forty two members of the Australian Dental Association (New South Wales Branch), were randomly selected and sent questionnaires. Eighty per cent (n = 355) responded. No significant differences in reported symptoms were found when considering age, experience, handedness, operating position or period of working without a break. Eighty-two per cent of the respondents reported experiencing one or more musculoskeletal symptoms during the previous month. Sixty-four per cent of the sample reported suffering pain (the majority reported back pain) and 58 per cent headaches. Most severe symptoms reported were pain (39%) and headaches (25%). Those in the youngest age category of less than 35 years (26%), were significantly more likely to have headaches (chi 2 4df p < 0.05). Female dentists were more likely to rate the severity of their most severe symptom higher (chi 2 1df p < 0.05), and to report more frequent pain (chi 2 2df p < 0.05) and headaches (chi 2 2df p < 0.05). Those practising four-handed dentistry were significantly more likely to be in the 35-44 age range (chi 2 4df p < 0.01), to work for longer periods before taking a 10-minute break (chi 2 5df p < 0.05) and to report frequent pain (chi 2 2df p < 0.05). The results support the findings of previous studies conducted overseas but additional information about musculoskeletal symptoms in this occupational group has been identified.
206 citations
TL;DR: The present paper reviews the results of this author's own decade of research into the oral development of preterm children in the light of current understanding of the field and demonstrates that the rate of dental development, and dental eruption may be affected by preterm birth.
Abstract: Preterm and low birthweight children comprise approximately 6 per cent of all live births. They are prone to many serious medical problems during the neonatal period which may affect the development of oral tissues. The present paper reviews the results of this author's own decade of research into the oral development of preterm children in the light of current understanding of the field. Studies have shown a high prevalence of generalized enamel hypoplasia in the primary dentition of around 40-70 per cent in preterm children which is likely to be associated with low bone mineral stores. The clinical significance of enamel defects is poor aesthetics, and predisposition of the lesions to dental caries. Other dental defects observed in preterm children are localized enamel hypoplasia, crown dilacerations, and palatal distortions which are usually associated with traumatic laryngoscopy and prolonged endotracheal intubation. Furthermore, recent studies have demonstrated that the rate of dental development, and dental eruption may be affected by preterm birth. Children with the lowest birthweight and shortest gestational ages have the lowest rates of dental development, particularly before six years of age. The results of these clinical studies may have significant implications in the dental management of preterm children.
179 citations
TL;DR: The best preventive strategy would appear to be an assessment of risk factors prior to banding, coupled with fluoride rinses, regular reinforcement of oral hygiene, and dietary advice throughout the course of treatment.
Abstract: The aetiology of enamel demineralization during fixed orthodontic treatment and its sequelae are discussed. A summary is given of the various methods available to assess the risk of demineralization prior to active treatment. The best preventive strategy would appear to be an assessment of risk factors prior to banding, coupled with fluoride rinses, regular reinforcement of oral hygiene, and dietary advice throughout the course of treatment.
164 citations
TL;DR: This study supports previously reported levels of neurological damage and confirms that panoramic radiography is the optimum method for radiological assessment for mandibular third molar teeth prior to their removal.
Abstract: Permanent alteration of sensation in the lip after the removal of mandibular third molar teeth is an unusual but important complication. Studies have been performed to assess the risk of nerve damage but most of these have been retrospective and poorly controlled. This prospective trial predicted the outcome of altered sensation prior to surgery based on assessment of a panoramic radiograph and correlated this with the result postoperatively in the consecutive removal of 479 third molar teeth. Results indicated that 5.2 per cent had transient alteration in sensation but only one patient (0.2 per cent) had prolonged anaesthesia. As 94.8 per cent of teeth extracted had no neurological sequelae the figures for prediction were skewed and a kappa statistical analysis of 0.27 illustrated a fair level of agreement between prediction and outcome. This study supports previously reported levels of neurological damage and confirms that panoramic radiography is the optimum method for radiological assessment for mandibular third molar teeth prior to their removal.
106 citations
TL;DR: The results showed that about one in seven practitioners had had to resuscitate a patient and the most common medical emergencies were adverse reactions to local anaesthetics, grand mal seizures, angina pectoris and hypoglycaemia (insulin shock).
Abstract: This is a report of a postal questionnaire survey of 1250 general dental practitioners regarding occurrence of medical emergencies and their choice of emergency drugs and equipment. The response rate was 65 per cent and the results showed that about one in seven practitioners had had to resuscitate a patient. The most common medical emergencies were adverse reactions to local anaesthetics, grand mal seizures, angina pectoris and hypoglycaemia (insulin shock). Nearly all respondents (96 per cent) believed that dentists need to be competent in cardiopulmonary resuscitation, just over a half (55 per cent) felt they were competent in CPR on graduation and a similar figure (57 per cent) felt they could perform effective single person CPR for five minutes. Almost two-thirds (64 per cent) had undertaken CPR courses since graduation. Additionally, the most commonly kept emergency drugs were oxygen (63 per cent) and adrenaline (22 per cent), while the most commonly kept emergency equipment was a manual resuscitator (recoil bag-valve-mask type) which was kept by 27 per cent of the practitioners.
106 citations
TL;DR: The results indicate that periodontal probing can cause bacteraemia in patients with periodontitis and it would be advisable for patients considered at risk of developing infective endocarditis to receive antibiotic prophylaxis for periodontAL probing if they have radiographic evidence ofperiodontitis.
Abstract: Bacteraemia of oral origin may result in infective endocarditis in susceptible individuals. The aim of this pilot study was to investigate the occurrence of bacteraemia due to periodontal probing. Thirty patients (15 male, 15 female; mean age 42.7 years) with untreated periodontitis were investigated. All were free of significant medical disorders and none had taken antibiotics in the previous month. Prior to and immediately following periodontal probing, 20 mL of venous blood were obtained from each patient and inoculated into aerobic and anaerobic blood culture bottles and incubated. Negative bottles were monitored continuously for three weeks before being discarded. Periodontal probing consisted of measuring pockets at six points around each tooth and recording the presence or absence of bleeding. A positive bacteraemia was recorded for three of the patients prior to probing. One patient exhibited Prevotella species whilst two exhibited skin commensals. Following probing, 13 patients (43 per cent) exhibited bacteraemia of oral origin. Viridans streptococci were the most common isolates (45 per cent). No significant correlations were found between bacteraemia and the severity of periodontitis or extent of bleeding on probing. The results indicate that periodontal probing can cause bacteraemia in patients with periodontitis. It would be advisable for patients considered at risk of developing infective endocarditis to receive antibiotic prophylaxis for periodontal probing if they have radiographic evidence of periodontitis.
84 citations
TL;DR: An overview of condylar injuries in growing patients is presented for the purpose of increasing the awareness of all dental practitioners involved in the treatment of children with acute oro-facial injuries.
Abstract: Although the mandibular condyle is one of the most common sites of injury of the facial skeleton, it is also the most overlooked and least diagnosed site of trauma in the head and neck region. The condyle forms the very cornerstone of mandibular form and function and therefore injuries to the mandibular condyle in growing children may adversely affect growth and development of the jaws and the occlusion. The aim of this article is to present an overview of condylar injuries in growing patients for the purpose of increasing the awareness of all dental practitioners involved in the treatment of children with acute oro-facial injuries.
71 citations
TL;DR: A combined surgical and orthodontic technique for management of transverse maxillary deficiencies in mature patients is described and discussed, withications for the use of this surgically-assisted maxillary expansion technique, and its advantages when compared with segmented surgical expansion.
Abstract: A combined surgical and orthodontic technique for management of transverse maxillary deficiencies in mature patients is described and discussed. Special references are made to the surgical release of several circummaxillary articulations to facilitate the use of a fixed expansion device, and to the authors' addition of an osteotomy below the nasal spine, to ensure that the nasal septum remains independent of the maxillary segments. Indications for the use of this surgically-assisted maxillary expansion technique, and its advantages when compared with segmented surgical expansion, are also presented.
TL;DR: A case of natal teeth associated with traumatic ulceration to the ventral surface of the tongue (Riga-Fedes syndrome) in a four week old boy is presented, and two teeth, present at birth, were found to be early erupted deciduous lower central incisors.
Abstract: A case of natal teeth associated with traumatic ulceration to the ventral surface of the tongue (Riga-Fedes syndrome) in a four week old boy is presented. On radiographic examination, two teeth, present at birth, were found to be early erupted deciduous lower central incisors. A family history of natal teeth, all involving both lower deciduous central incisors associated with trauma to the tongue during suckling, was elicited. The ulceration healed over a period of four weeks using an innovative conservative treatment regime, involving the use of Stomahesive Wafer. Four months later the only sign of any previous pathosis was a fibrous scar on the ventral surface of the tongue.
TL;DR: It is concluded that the SDS sealant programme is a sound preventive dental public health approach.
Abstract: The benefit of a public sector sealant programme for children in Australia is yet to be established. This study evaluated sealants placed by therapists of the School Dental Service in Victoria, between 1989 and 1994, on permanent teeth of children in 15 primary schools in Melbourne. Seven hundred and seventy four children aged 6-12 years were examined in school dental clinics by six calibrated examiners. A total of 5363 sealants placed on 2875 permanent teeth (including 2616 first molars, 91 per cent of sample) up to four and a half years previously was examined. Values for complete and partial sealant retention were highest for premolars (86 per cent, 9 per cent respectively, total 95 per cent); similar for occlusal surfaces of maxillary and mandibular first molars (63 per cent, 30 per cent; 62 per cent, 32 per cent respectively) and buccal pits of mandibular molars (66 per cent); and low for pits/fissures of Carabelli's cusps of maxillary molars (44 per cent). Cross-sectional examination up to 24 months for both maxillary and mandibular first molars indicated average values of 67 per cent complete retention, 27 per cent partial retention, 6 per cent missing; thereafter complete retention decreased and partial retention increased. Sealant failures in the six months post-placement were attributed to technique failure. Regardless of sealant retention, caries experience was low under partially retained or missing sealants (4.5 per cent) and completely retained sealants (0.4 per cent). It is concluded that the SDS sealant programme is a sound preventive dental public health approach.
TL;DR: An adenomatoid tumour was found in the anterior maxillary region of a 15 year old female patient and two impacted teeth were found inthe tumour.
Abstract: An adenomatoid tumour was found in the anterior maxillary region of a 15 year old female patient Two impacted teeth were found in the tumour The lateral incisor found in the tumour was dilacerated, and the roots of the first premolar were resorbed A review of the English literature indicated that 294 similar cases have been reported
TL;DR: The antimicrobial activity of 2,4,2'-trihydroxy-5'-methylchalcone against both primary and secondary causative agents suggests it could be useful as a potent therapeutic agent in denture stomatitis.
Abstract: In the antimicrobial therapy of denture stomatitis, it is desirable to inhibit the growth of not only the primary causative organism, Candida albicans, but also other oral bacteria closely associated with the condition. Three synthetic anti-candidal chalcones were characterized and compared for their additional activity in inhibiting these causative bacteria. Among the tested chalcones, 2,4,2'-trihydroxy-5'-methylchalcone showed the highest activity for different Gram-positive bacteria. It inhibited the growth of streptococci, staphylococci and lactobacilli at 25.0-50.0 micrograms/mL which was lower than or comparable to its minimum inhibitory concentration for candida. It functioned with a bactericidal action and leaked 260 nm-absorbing substances from the streptococcal cells. The antimicrobial activity of 2,4,2'-trihydroxy-5'-methylchalcone against both primary and secondary causative agents suggests it could be useful as a potent therapeutic agent in denture stomatitis.
TL;DR: This report provides epidemiological data describing caries experience among the population of non-institutionalized older adults in Adelaide and Mt Gambier and finds differences were statistically significant only among age groups.
Abstract: This report provides epidemiological data describing caries experience among the population of non-institutionalized older adults in Adelaide and Mt Gambier. Subjects were selected in a stratified random sample of persons aged 60+ who were listed on the South Australian Electoral Database. Oral examinations were conducted by four calibrated dentists among 853 dentate persons aged 60 years and over. There was an average of 14.7 missing teeth, 8.3 filled teeth and 0.3 decayed teeth, and a further 0.2 teeth were present as retained roots. The mean number of missing teeth was higher (p < 0.05) in older compared with younger age groups, and in Mt Gambier compared with Adelaide. The mean DFS of 22.1 was significantly higher (p < 0.05) among younger persons, females and in Adelaide. Root surface caries affected an average of 3.1 surfaces, and was greater (p < 0.05) among persons aged 70-79 years, males and Adelaide residents. However, when root caries was expressed as an attack rate per 100 exposed surfaces, differences were statistically significant only among age groups. Analysis of specific teeth revealed that no more than 40 per cent of molars were retained, and between 30 and 58 per cent of retained molars had coronal fillings.
TL;DR: Overall, dental chairside assistants experienced a higher incidence of injuries than students both on a per worker and per time basis, and a range of factors which contribute to the calculation of indirect costs following injuries in the dental workplace are identified.
Abstract: Workplace injuries at the University of Queensland Dental School during the period 1992-1994 were assessed to determine their incidence, and the associated indirect costs, causal factors, and appropriate preventive strategies. Overall, dental chairside assistants experienced a higher incidence of injuries than students both on a per worker and per time basis. Of the injuries with a low risk of cross-infection, burns and scalds from sterilizing equipment, and eye injuries in laboratories were the most common. This emphasizes the importance of wearing appropriate protective equipment in areas outside the treatment zone, and the need for signage and education. Common causes of sharps injuries were burs left in handpieces, two-handed needle recapping, and cleaning of probes in the sterilizing room. Changes to techniques and equipment would prevent such incidents. A range of factors which contribute to the calculation of indirect costs following injuries in the dental workplace are identified.
TL;DR: An audit of the waste practices of ten general dental surgeries identified problems that have occurred due to the lack of specific dental guidelines or codes of practice in this area.
Abstract: An audit of the waste practices of ten general dental surgeries identified problems that have occurred due to the lack of specific dental guidelines or codes of practice in this area Occupational health and safety requirements for types and locations of sharps containers, and lack of consensus on what constitutes a sharp, were identified as areas needing attention Cross-infection control items, such as gloves, masks, single-use cups, and protective coverings, were found to constitute up to 91 per cent of total waste When infectious waste was reclassified by the audit team as ‘that waste which was visibly blood stained,’ a reduction in waste in this category was made, during the audit, at each practice The practice of disposing of radiographic fixer and developer into the sewerage system occurred in three out of the ten practices, even though the Australian Dental Association Inc has discouraged this practice
TL;DR: In 15 patients, who underwent root resections of the upper incisors on both sides, the incision lines were closed with silk sutures on one side and by n-butyl-2-cyanoacrylate on the other side of the frenum.
Abstract: The use of tissue adhesives as an alternative to or replacement for sutures in wound closure has long been an area of interest. One of these tissue adhesives is a cyanoacrylate. In 15 patients, who underwent root resections of the upper incisors on both sides, the incision lines were closed with silk sutures on one side and by n-butyl-2-cyanoacrylate on the other side of the frenum. Clinical comparison was made on the 1st, 2nd, 3rd, 7th, 14th and 21st postoperative days. On the seventh postoperative day following the removal of sutures and the coating, small punch biopsies were obtained from n-butyl-2-cyanoacrylate treated and sutured sides. The tissue specimens were examined under transmission electron microscope. Clinical observations revealed that on the third and seventh postoperative days epithelialization was better on the sides treated with n-butyl-2-cyanoacrylate. On the twenty-first postoperative day it was observed that the scar formation was significantly more marked and there was more local inflammation during the healing period on the sutured side. Electron microscopic observations of both tissue specimens revealed normal ultrastructural morphology.
TL;DR: The article examines such features as the gender breakdown of first-year students, age at the end of their first year, their own and their parents' countries of origin, English and non-English language proficiency, type of school attended, and motivations for choosing dentistry as a career.
Abstract: There has been constant interest in the background of dentistry students over the years. This paper, based on the data amassed by surveying the first-year dentistry students of 1994 and 1995, builds on previous questionnaires and publications, and shows that certain trends in student make-up, predicted earlier, have been checked. The article examines such features as the gender breakdown of first-year students, age at the end of their first year, their own and their parents' countries of origin, English and non-English language proficiency, type of school attended, parents' occupations, parents' highest level of education, motivations for choosing dentistry as a career, aptitude for a career in dentistry, and previous studies and employment. The data are analysed with the view to determining changes over time in the social composition of dentistry students.
TL;DR: There were no significant effects on restoration survival from change, of dentist, and generally only one or two types of restorations had their survivals influenced significantly either by dental practice location, or by patient age, frequency of patient attendance, experience, and whether or not the restoration were replacements during the study period.
Abstract: Very little is known of dentist and patient factors which may influence the survival or longevity of dental restorative materials placed in private practices. The present retrospective study investigated during 1992 the effects of six factors on the long-term survivals of five types of restorations placed by 20 male dentists in 100 adult patients, at 3 selected Adelaide dental practices. There were no significant effects on restoration survival from change of dentist, and generally only one or two types of restorations had their survivals influenced significantly either by dental practice location, or by patient age, frequency of patient attendance, experience of dentist, and whether or not the restorations were replacements during the study period. Restoration survival was not influenced significantly by whether, or not, any replacements were made by the dentist who placed the initial restorations. The median survival times for amalgams were 22.52 years, resin composites 16.72 years, castings 13.75 years, and crowns an estimated 26 years. For glass-ionomers, 75 per cent were still present at 11.25 years.
TL;DR: A case of Eagle's syndrome masquerading as pain of dental origin is presented and the literature is reviewed.
Abstract: Eagle's syndrome, also known as elongated styloid process, is a condition that may be the source of craniofacial and cervical pain. It is infrequently reported but is probably more common than generally considered. The symptoms related to Eagle's syndrome can be confused with those attributed to a wide variety of facial neuralgias and/or oral, dental and TMJ diseases. In this paper, a case of Eagle's syndrome masquerading as pain of dental origin is presented and the literature is reviewed.
TL;DR: The aim of the present paper was to extend the annual reporting on caries experience in Australia up to and including 1993, and to document the change in the distribution of caries within the child population since 1977.
Abstract: Data on the dental health of Australian school children from 1977 to 1985 have previously been reported. Significant features included a secular decline in caries experience as defined by the number of decayed, missing and filled teeth in both the deciduous dentition (dmft index) and permanent dentition (DMFT index), and a change in the distribution of caries experience within the child population in Australia, indicated by increasingly smaller percentages of children accounting for greater proportions of total disease experience. The aim of the present paper was to extend the annual reporting on caries experience in Australia up to and including 1993, and to document the change in the distribution of caries within the child population since 1977. In addition, the data are compared with dental targets for children for the year 2000 in Australia and internationally. Caries data were obtained for the years 1977-1993 for children who were patients at School Dental Services in each State and Territory of Australia. Caries experience was recorded by uncalibrated dentists and dental
TL;DR: Results indicate that shear bond strengths in the order of 10 MPa can be obtained reliably on human teeth using laser conditioning with pulsed modes in the absence of any other preparation of the natural enamel surface.
Abstract: Carbon dioxide (CO2) lasers are capable of producing surface irregularities in human enamel which resemble those resulting from etching of enamel with orthophosphoric acid. This report presents the results of a laboratory study which examined the effect of selected tooth-related variables on shear bond strength between a current generation bonding agent (Scotchbond MultiPurpose) and acid-etched or laser-conditioned human enamel. There were no significant differences in shear bond strength between human maxillary central incisor teeth, first premolars, and third molars in either the acid etch or laser-conditioned groups. Polishing of enamel to give a flat surface increased the shear bond strength obtained with acid etching, but did not alter significantly bond strengths achieved with laser conditioning. There was a tendency for a higher bond strength with acid etching, but not with laser conditioning, in porcine molar enamel compared with human molar and bovine incisor enamel. In terms of the mode of operation of the laser, the repetitively pulsed mode resulted in a two-fold improvement in shear bond strength compared with the single pulse mode. These results indicate that shear bond strengths in the order of 10 MPa can be obtained reliably on human teeth using laser conditioning with pulsed modes in the absence of any other preparation of the natural enamel surface.
TL;DR: Tests showed that the inclusion of air cells in a 4 mm thick polyvinyl-acetate-polyethylene (EVA) copolymer reduced the effects of impacts of less than 10 kN when compared with a material of the same EVA composition and thickness.
Abstract: A modified mouthguard material which reduces transmitted forces is described. Tests showed that the inclusion of air cells in a 4 mm thick polyvinyl-acetate-polyethylene (EVA) copolymer reduced the effects of impacts of less than 10 kN when compared with a material of the same EVA composition and thickness. The EVA copolymer with air-inclusions is suitable for the construction of stock mouth-formed and vacuum-formed mouthguards. The improved elastic properties of the modified mouthguard material reduced transmitted forces by 32 per cent when compared with traditional EVA mouthguard polymers of the same thickness.
TL;DR: In vitro testing conducted in the present investigation indicates that application of 40% silver fluoride to deep carious lesions or its use as a 'spot' application agent could result in 3 to 4 mg of fluoride reaching the systemic circulation.
Abstract: Due to its exceedingly high fluoride content, 40% silver fluoride solution has the potential to cause fluorosis when used in young children. In vitro testing conducted in the present investigation indicates that application of 40% silver fluoride to deep carious lesions or its use as a 'spot' application agent could result in 3 to 4 mg of fluoride reaching the systemic circulation. As scientifically-based clinical trials on the safety of 40% silver fluoride have not been conducted, it would be appropriate for it to be withdrawn from further clinical use until proper testing and evaluation have been carried out. In view of the possibility that lower strength solutions of silver fluoride (1-4%) may be just as effective as 40% in 'arresting' deep caries, testing should focus on such solutions, particularly as the potential for toxicity from their fluoride content would be reduced by a factor of 10-40.
TL;DR: Any product that contains 120,000 ppm [F] should be regarded as carrying a high risk of toxicity when used on young children, and currently available commercial preparations contain silver difluoride rather than silver fluoride.
Abstract: Instead of expected fluoride ion concentrations of around 60,000 ppm, commercial preparations of 40 per cent aqueous silver fluoride were found to contain 120,000-127,000 ppm. Information received from the Western Australian Chemistry Centre which provided independent confirmation of the higher than expected [F] indicates that the currently available commercial preparations contain silver difluoride rather than silver fluoride. In view of the potential of fluoride-containing products such as dentifrices (1000-1500 ppm F) and topical fluoride gels and solutions (6000-12,000 ppm F) to cause adverse effects if excessive quantities are ingested, any product that contains 120,000 ppm [F] should be regarded as carrying a high risk of toxicity when used on young children.
TL;DR: The ultrastructure of A. israelii was investigated by electron microscopy and revealed the presence of hairlike fimbriae protruding through a thick surface coat on some species, whilst thin sectioning disclosed a Gram-positive cell wall surrounded by a fuzzy outer coat.
Abstract: Actinomyces israelii is the most common cause of human actinomycosis, a chronic granulomatous infection. Periapical actinomycosis involving A. israelii has been identified as an important cause of failure of conventional endodontic treatment. Structures on the bacterial cell surface have been implicated in the pathogenicity of Actinomyces. In this study the ultrastructure of A. israelii was investigated by electron microscopy. Negatively stained preparations revealed the presence of hairlike fimbriae protruding through a thick surface coat on some species, whilst thin sectioning disclosed a Gram-positive cell wall surrounded by a fuzzy outer coat. These structures may be important for the pathogenicity of A. israelii.
TL;DR: The influence of variables in techniques and experimental design on the results of the studies reviewed is discussed and the role of the provision of a cement space in reducing post-cementation crown elevation is presented.
Abstract: This paper reviews the relevant dental literature concerning the effect of die-spacing on crown elevation and pre- and post-cementation crown retention. Techniques of providing die-spacing and measurement of the thickness of die-spacer are discussed. A review of the role of the provision of a cement space in reducing post-cementation crown elevation is presented. Factors which may affect crown retention prior to and following cementation are also reviewed. The influence of variables in techniques and experimental design on the results of the studies reviewed is discussed.
TL;DR: Difficulties in providing restorative care, either under local anaesthesia or general anaesthesia are discussed, and a novel replacement of non-viable carious anterior teeth using a nine-unit porcelain fused to metal Rochette type bridge is presented.
Abstract: These two case reports highlight the enormous clinical difficulties faced by dentists in providing satisfactory long-term dental care to patients who suffer from Epidermolysis bullosa. Problems of bullae formation in oral soft tissues and subsequent scarring are outlined in relation to the difficulty of maintaining satisfactory oral hygiene and a diet leading to minimal dental caries experience. The behavioural problems of maintaining patient compliance for preventive and restorative dentistry in this painful and debilitating disease are illustrated in these case reports. Difficulties in providing restorative care, either under local anaesthesia or general anaesthesia are discussed, and a novel replacement of non-viable carious anterior teeth using a nine-unit porcelain fused to metal Rochette type bridge is presented. Dental management of patients with Epidermolysis bullosa should commence at birth, and non-compliance in dental attendances should be followed up by social workers to prevent the disastrous oral morbidity that frequently occurs in such patients.