Health effects of nutrients and environmental pollutants in Baltic herring and salmon: a quantitative benefit-risk assessment

BACKGROUND

Health risks linked with dioxin in fish remain a complex policy issue. Fatty Baltic fish contain persistent pollutants, but they are otherwise healthy food. We studied the health benefits and risks associated with Baltic herring and salmon in four countries to identify critical uncertainties and to facilitate an evidence-based discussion.

METHODS

We performed an online survey investigating consumers' fish consumption and its motivation in Denmark, Estonia, Finland, and Sweden. Dioxin and methylmercury concentrations were estimated based on Finnish studies. Exposure-response functions for several health endpoints were evaluated and quantified based on the scientific literature. We also quantified the infertility risk of men based on a recent European risk assessment estimating childhood dioxin exposure and its effect on sperm concentration later in life.

RESULTS

Baltic herring and salmon contain omega-3 fatty acids and vitamin D, and the beneficial impact of these fishes on cardiovascular diseases, mortality, and the risk of depression and cancer clearly outweighs risks of dioxins and methylmercury in people older than 45 years of age and in young men. Young women may expose their children to pollutants during pregnancy and breast feeding. This study suggests that even in this critical subgroup, the risks are small and the health benefits are greater than or at least similar to the health risks. Value of information analysis demonstrated that the remaining scientific uncertainties are not large. In contrast, there are several critical uncertainties that are inherently value judgements, such as whether exceeding the tolerable weekly intake is an adverse outcome as such; and whether or not subgroup-specific restrictions are problematic.

CONCLUSIONS

The potential health risks attributable to dioxins in Baltic fish have more than halved in the past 10 years. The new risk assessment issued by the European Food Safety Authority clearly increases the fraction of the population exceeding the tolerable dioxin intake, but nonetheless, quantitative estimates of net health impacts change only marginally. Increased use of small herring (which have less pollutants) is a no-regret option. A more relevant value-based policy discussion rather than research is needed to clarify official recommendations related to dioxins in fish.

Effects of Cytotoxic Chemotherapy on Dental Development

A histological study of 21 teeth from 9 patients who had received cytotoxic chemotherapy for malignant disease showed increased prominence of incremental lines in the dentine. The number and distribution of these lines corresponded to periods of intravenous therapy and vincristine appeared to be the most likely cause. This effect was probably due to temporary disturbance of microtubular function in the odontoblasts resulting in decreased secretion of collagenous dentine matrix. Calcification appeared to be unaffected.

Hexachlorobenzene-Induced Incisor Degeneration in Sprague—Dawley Rats

Hexachlorobenzene (HCB) was administered to female Sprague—Dawley rats in a 13-week toxicity study conducted for the National Toxicology Program (NTP). Groups of 10 rats were treated by gavage with 0.0, 0.03, 0.1, 0.3, 1.0, 3.0, 10, or 25 mg/kg HCB in corn oil 5 days/week for 13 weeks. Dose-dependent, region-specific, maxillary incisor degeneration was observed in animals given HCB at doses of 1.0 mg/kg/day and higher. Treatment with 1.0 mg/kg/day resulted in focal mesenchymal cell vacuolation and focal osteodentin formation within the pulp. Lesions were restricted to a short linear region subjacent to the odontoblast layer along the lateral aspect of the incisor at the level of the dentin-enamel interface. When observed in both incisors, lesions were bilaterally symmetric. Treatment with 3.0 mg/kg/day resulted in lateral and medial pulp lesions and focal odontoblast degeneration with dentin niche formation along the lateral incisor margin in some animals. Treatment with 10 mg/kg/day resulted in a higher incidence of lateral dentin niches and a low incidence of medial dentin niches. In animals treated with 25 mg/kg/day, a high incidence of bilaterally symmetric, lateral and medial, dentin niches were observed. The morphology and distribution of HCB-induced incisor lesions in rats are consistent with injury to a selective population of preodontoblasts.

Odontoiatric perspectives and osteonecrosis of the jaw as a possible adverse effect of bisphosphonates therapy in fibrous dysplasia and McCune-Albright syndrome

BACKGROUND

McCune-Albright syndrome (MAS) is characterized by the triad of polyostotic bone fibrous dysplasia (PFD), endocrine disorders, and café-au-lait skin pigmentation. Ninety percent of MAS patients have fibrous dysplasia (FD) craniofacial lesions. Osteonecrosis of the jaw (ONJ) has been described as an adverse side effect of bisphosphonate therapy. The aim of the study was to investigate evidence of clinical and/or radiological signs of ONJ in FD/MAS pediatric patients due to bisphosphonate therapy and describe odontoiatric tools in this population.

METHODS

Thirteen FD/MAS patients were enrolled. All patients during pediatric age have been treated with pamidronate infusions. They underwent complete oral clinical examination. Ortopantomography and/or CT were evaluated in all cases.

RESULTS AND CONCLUSIONS

No patient developed ONJ. None of them showed radiological signs different from jaw FD. In spite of the low number of patients enrolled, results confirm that, in this population, ONJ can be ruled out as a chronic adverse side effect of bisphosphonate therapy.

Dental disease patterns in methamphetamine users: Findings in a large urban sample

BACKGROUND

The authors used a large community sample of methamphetamine (MA) users to verify the patterns and severity of dental disease and establish a hierarchy of caries susceptibility by tooth type and tooth surface.

METHODS

Using a stratified sampling approach, 571 MA users received comprehensive oral examinations and psychosocial assessments. Three calibrated dentists characterized dental and periodontal disease by using National Health and Nutrition Examination Survey protocols. The authors also collected data on substance use history and other attributes linked to dental disease.

RESULTS

On all dental outcome measures, MA users evidenced high dental and periodontal disease, with older (≥ 30 years) and moderate or heavy MA users disproportionately affected. Women had higher rates of tooth loss and caries, as well as a greater prevalence of anterior caries. Current cigarette smokers were more likely to manifest 5 or more anterior surfaces with untreated caries and 3 or more teeth with root caries. Nearly 3% were edentulous, and a significant percentage (40%) indicated embarrassment with their dental appearance.

CONCLUSIONS

MA users have high rates of dental and periodontal disease and manifest a dose-response relationship, with greater levels of MA use associated with higher rates of dental disease. Women and current cigarette smokers are affected disproportionately. The intraoral patterns and hierarchy of caries susceptibility in MA users are distinctive.

PRACTICAL IMPLICATIONS

The prevalence and patterns of dental and periodontal disease could be used to alert dentists to possible covert MA use and to plan treatment. Concerns about dental appearance have potential as triggers for behavioral interventions.

The significance of ecstasy use to dental practice

3,4 Methylenedioxymethampetamine (MDMA), commonly known as ecstasy, is an illicit drug used by individuals seeking mood enhancement. Ecstasy's pharmacology, systemic, oral and dental manifestations are presented. Use of this drug is not limited to a particular socioeconomic class and, as such, all practicing dentists must be aware of both the intra-oral effects of this drug and any possible alterations to dental treatment that might become necessary. Dental manifestations include bruxism, increased incidence of caries, xerostomia and oral ulcers.

Drug abuse identification and pain management in dental patients: a case study and literature review

Properly identifying patients with a history of drug abuse is the first step in providing effective dental care. Dental professionals need to be fully aware of the challenges associated with treating this population. In the current study, the authors analyzed the physical and oral manifestations of illicit drug abuse to aid in the identification of patients who abuse drugs and the pain management strategies needed to treat them. The authors also present a clinical case of a patient with unique skin lesions and discuss the typical clinical findings of drug abuse based on a literature review.

Adverse drug reactions: oral and dental manifestations and complications

Adverse, that is unintended untoward effects of medications, are increasing in incidence and their severity, given the aging of the Australian and New Zealand population and associated drug use. Not only are the number of agents that our patients are using increasing, including the increased use of "alternate" or "complimentary" medications, but also their complexity, with the advent of potent, targeted, biological agents. The result is an increasing number of our patients will be at greater risk of adverse effects from their medications. These adverse effects include the impeding of the safe delivery of dental treatment and the adverse oral and dental manifestations and complications related to the use of medications.

[Effect of harmful chemical air impurities on some parameters of the oral cavity]

The paper describes guidelines for studying the role of harmful chemical air impurities at work in the development of diseases of the teeth and periodontium, by applying the nonparametric methods that can substantiate conclusions on the nature and mechanism of a cause-and-effect relation when the number of observations is limited.

[Alcopops: systemic and dental consequences]

Alcopops are highly-sweetened premixed spirit-based drinks. Ready to drink and sold in small bottles, it contains between 3 and 5 % alcohol by volume, sugars, citric and malic acid with a pH around 3. Their success is attributed to the fact that spirits are more palatable and better tasting with a fruity flavour, similar to non alcoholic beverages. Especially aimed at female teenagers in search for the alcohol effect while disliking its strong taste, it has been sold in Europe for 15 years. So called "designer drinks" are often consumed during the weekend, binge-drinked with some friends. The frequent consumption has severe consequences on general health, which includes body overweight due to the amount of sugar, and alcohol-related consequences of utmost importance considering consumer's young age. Moreover, alcopops may introduce to the consumption of alcohol and induce addiction. Consequences on oral health may include dental erosion. Erosion is a premature loss of mineralized tissues (enamel and dentin), due to the contact with acids. The low pH of these drinks and the increased risk of vomiting because of an excessive alcohol intake could potentially lead to substantial damage to the teeth. The treatment depends on the erosion stage. The medical professionals should be aware of the possible implications relating to alcopops' consumption. Some preventive advices can be given to the teenagers and to their parents: reduce acids consumptions, do not brush the teeth immediately after an acid drink and regularly visit a dentist.

Paediatric patients receiving oncology therapy: review of the literature and oral management guidelines

AIM

In recent years, neoplastic diseases in children have acquired growing importance in the field of paediatrics. This has been accompanied by significant advances in the treatment of children's cancer, with long-term survival rates of 90% in the case of some tumors, resulting in the need for more medical and health care on all levels. With these advances comes a new responsibility to do everything possible to prevent complications stemming from neoplasia and its treatment. Among the side effects of cancer therapies (mainly chemotherapy and radiation treatment) are chronic or acute oral manifestations that are frequent sources of discomfort, focal points of systemic infections and other side effects, depending on the child's stage of development. In most cases, the incidence and severity of oral complications are associated with preexisting factors (cavities, gum disease and poor hygiene) that clearly affect their emergence, increase and persistence. The aim of this article is to propose a guideline for managing oral complications of paediatric cancer treatments.

CONCLUSIONS

It is fundamental for the patient and their parents to be aware of the possibility of preventing or reducing problems in the oral cavity through preventive measures and simple oral treatment.

Current opinion on drug-induced oral reactions: a comprehensive review

AIM

The aim of this comprehensive review is to present an update to our previous review about drug-induced oral reactions. All drugs that may cause adverse effects in the mouth and related structures are reviewed.

BACKGROUND

Every drug can produce untoward consequences even when used according to standard or recommended methods of administration. Adverse drug reactions can involve every organ and system of the body and are frequently mistaken for signs of underlying disease. The mouth and associated structures can also be affected by many drugs or chemicals. Good oral health including salivary function is very important in maintaining whole body health. Drug reactions can be categorized as to the parts of the oral complex such as the oral mucosa and tongue, periodontal tissues, dental structures, salivary glands, cleft lip and palate, muscles, and nerves.

REVIEW RESULTS

This review suggests the number of drugs and chemicals that can produce adverse or toxic reactions in the oral cavity are on the rise. An updated listing of offending drugs is provided along with current strategies for dealing with adverse reactions.

CONCLUSION

Clinicians must constantly update their knowledge of drugs used by their patients. Attention must be paid to their toxic and unwanted effects that in many cases may be similar to characteristics of common diseases.

CLINICAL SIGNIFICANCE

Dentists and specialists of oral diseases should be aware of adverse drug oral reactions for better diagnosis of oral diseases, administration of drugs, and patient compliance during drug therapy.

Fluorides in groundwater and its impact on health

Fluoride is a naturally occurring toxic mineral present in drinking water and causes yellowing of teeth, tooth problems etc. Fluorspar, Cryolite and Fluorapatite are the naturally occurring minerals, from which fluoride finds its path to groundwater through infiltration. In the present study two groundwater samples, Station I and Station II at Hyderabad megacity, the capital of Andhra Pradesh were investigated for one year from January 2001 to December 2001. The average fluoride values were 1.37 mg/l at Station I and 0.91 mg/l at Station II. The permissible limit given by BIS (1983) 0.6-1.2 mg/l and WHO (1984) 1.5 mg/l for fluoride in drinking water. The groundwaters at Station I exceeded the limit while at Station II it was within the limits. The study indicated that fluoride content of 0.5 mg/l is sufficient to cause yellowing of teeth and dental problems.

Smokable ("ice", "crystal meth") and non smokable amphetamine-type stimulants: clinical pharmacological and epidemiological issues, with special reference to the UK

"Ice", "crystal meth", is the smokable form of methamphetamine hydrochloride. This paper will comment on the pharmacological, epidemiological, clinical and social issues related to smoking the drug as opposed to either its injection or ingestion. Furthermore, some data related to amphetamines/methamphetamines consumption, request for treatment, seizures, related offences and deaths in the UK (1990-2002) will be offered here. Peak rates, for most indicators, were reached at the end of the '90s, to fall down in the following years. The only indicator which seemed not to show any declining rates is number of deaths, but this may be related to a more general increase in stimulant death rates recently observed in the UK. It is argued that methamphetamines, and particularly "crystal meth", could reach the same prevalence levels of use in the UK as it is already in the US but recent reclassification of the drug to Class A in the UK could help to better control this emerging issue.

Methamphetamine abuse and "meth mouth"

Dental management for the patient who abuses drugs is always a challenge. The number of patients abusing methamphetamines appears to be increasing. The dentist needs to be aware of the clinical presentation and medical risks presented by these patients and to attempt to get the patient to seek professional help. Additionally, special attention will be necessary for the high prevalence and severity of oral manifestations including rampant caries, enamel erosion, xerostomia, bruxism, and muscle trismus.

Drug-induced disorders of teeth

It is essential that every health care professional who is involved with the prescription or recommendation of drugs be fully aware of any resultant disorders that may arise as a side-effect. A range of drugs can affect the teeth. In this review article, drugs that have the potential to induce changes in teeth have been classified as those leading to tooth discoloration (intrinsic and extrinsic), physical damage to tooth structure (enamel, dentin, and cementum), and alteration in tooth sensitivity.

No findings of dental defects in children treated with minocycline

Forty-one children <8 years of age treated for brucellosis with oral minocycline (2.5 mg/kg) twice daily for 3 weeks were recalled and examined to check for dental staining and defects. Dental staining and defects were found in 14 of 41 exposed children (34.1%) and in 30 of 82 matched controls (36.6%), respectively (P > 0.2).

Dental abnormalities in children after chemotherapy treatment for acute lymphoid leukemia

The frequency of dental abnormalities, such as delayed dental development, microdontia, hypoplasia, agenesis, V-shaped root and shortened root was evaluated in 76 acute lymphoblastic leukemia (ALL) pediatric patients who had been off chemotherapy for 6 months. These children had been subjected to one of the three Brazilian Protocols or the BFM86 Protocol. The patients were divided into three groups: Group I (GI; high risk) treated with one of the three Brazilian Protocols who received high-dose chemotherapy, intensive maintenance and cranial radiotherapy; Group II (GII; low risk) who were also treated with one of the three Brazilian Protocols using low-intensive chemotherapy with no radiotherapy; and Group III (GIII) based on the BFM86 Protocol. Of 76 children, 13 showed no dental abnormalities (8 were at the age of tooth formation). The remaining 63 children (82.9%) showed at least one dental anomaly. The abnormalities were probably caused by the type, intensity, frequency of the treatment and age of the patients at ALL diagnosis and this might have important consequences for the children's dental development.

Oral health in liver transplant children administered cyclosporin A or tacrolimus

BACKGROUND

Immunosuppression by cyclosporin A (CsA) is associated with adverse side-effects, including nephrotoxicity, neurotoxicity and gingival overgrowth. Tacrolimus (TAC/FK506) is a new immunosuppressive agent, recently approved for use in solid-organ transplants. The mode of action of TAC is similar to that of CsA and the toxicity profile of CsA is duplicated by TAC. The effect of TAC on the gingival tissue is not yet conclusive.

SAMPLE

Gingival overgrowth was assessed in 30 liver transplant children, 20 boys and 10 girls, aged 2-19 years. Seventeen children (10 boys, seven girls) were on a CsA-based immunosuppressive regimen whereas 13 children (10 boys, three girls) were on TAC for at least 1 year (mean 4.3 +/- 2.7).

RESULTS

In the CsA group, 35% of children exhibited gingival overgrowth characterized by one or more units with increased sulcus probing depth (> or = 4 mm), i.e. pseudopockets. In contrast to the CsA group, none of the children in the TAC group exhibited gingival overgrowth. The occurrence of enamel hypoplasia was observed in 11 children (36%) and enamel opacities were found in 23 children (76%). Six of the 12 children (50%) with hyperbilirubinaemia biliary atresia exhibited a marked greenish discoloration of the teeth. Caries experience (dmft/DMFT) among these children was 2.0 +/- 2.8.

CONCLUSION

No difference in caries experience or enamel defect was observed between the CsA and TAC group.

Developmental dental defects in children who reside by a river polluted by dioxins and furans

The authors determined that demarcated hypomineralizations of developing teeth are a biological indicator of an early dioxin exposure in a healthy population of children. In the current study, the authors examined the prevalences of the demarcated hypomineralization lesions of teeth in 2 Finnish towns by the Kymijoki River--a river that is severely contaminated by dioxins and furans. The 4,120 permanent first molars of 1,030 children were studied. The prevailing levels of dioxins and furans in human milk were measured. The prevalences of the defects in children in Kotka and Anjalankoski were 14.2% and 5.6%, respectively, and the corresponding dioxins and furans in human milk were 13.4 pg/gm fat and 10.9 pg/gm fat (International Toxic Equivalents). In Anjalankoski, the duration of total breast-feeding was associated with the prevalence of the defects. Compared with the figures reported earlier in Finland, neither the prevalence of dental lesions nor the levels of dioxins and furans in human milk were increased in riverside residents.

Heavy metal poisoning in glass worker characterised by severe

The paper presents the clinical description of the masticatory organ and biochemical assessment of dental tissue in a patient employed in a glassworks for 20 years. During 12 years the patient has suffered baldness ("Alopecia areata") and atypical extensive and non-healing cutaneous lesions. Dental examination revealed changes typical of chronic poisoning by cadmium and bismuth compounds.

Dental abnormalities in children treated for neuroblastoma

PURPOSE

To determine the frequency and types of dental abnormalities among children treated at a young age for cancer, as represented by neuroblastoma.

PATIENTS AND METHODS

We retrospectively reviewed the dental records and panoramic radiographs of 542 children who were treated for neuroblastoma at our institution over a 31-year period. Patients in our study had to meet the following criteria: they were treated on an institutional protocol, they had undergone panoramic radiography, and their dental follow-up continued for at least 2 years after diagnosis. We evaluated the frequency of clinically or radiographically apparent microdontia, excessive caries, root stunting, hypodontia, and enamel hypoplasia in our study population.

RESULTS

Of the 52 patients who met the study criteria, 71% developed dental abnormalities, comprising microdontia in 38%, excessive caries in 29%, root stunting in 17%, hypodontia in 17%, and enamel hypoplasia in 17%. In nearly half (23) of our patients, neuroblastoma was diagnosed on or before their first birthday.

CONCLUSION

Children treated for neuroblastoma are at high risk for abnormal dental development. The abnormalities in these patients may require extensive dental care and can compromise their quality of life. Frequent dental examinations and an intense oral hygiene program before, during, and after treatment may improve overall dental health.

Cadmium-induced dental lesions in ovariectomized rats

The effects of cadmium chloride on both incisor and molar teeth of ovariectomized female rats were studied histopathologically. The rats were injected intravenously with the compound at doses of 1.0 and 2.0 mg/kg, 5 days/wk. Six rats per group were sacrificed at 4, 8, and 13 wk. Discoloration of the incisors was observed in the rats of the 2.0-mg/kg group from 8 wk. Histopathologic examination of the incisor demonstrated decreased iron-containing pigment in ameloblasts and destruction of the enamel organ. These changes were accompanied with accumulation of cadmium and loss of iron in the teeth. Necrosis of the dental pulp occurred from the coronal end of both the incisor and molar teeth extended to the apical, deep portion of the teeth. The dental pulp of the molar teeth, which is shorter than that of the incisor, was mildly affected by cadmium intoxication. These findings suggested that intradental ischemia due to cadmium toxicity may have contributed to the development of the pulpal necrosis.

Pharmacologic management of patients with diseases of the endocrine system

Endocrine disorders are commonly seen in the general population. This article discusses the physiology, pathogenesis, and the medical and dental management of patients with thyroid, parathyroid, and pituitary gland disorders. In addition, the pharmacologic treatment, common side effects, and dental drug interactions of concern are discussed.

Review article. The rat incisor in toxicologic pathology

Microscopic examination of the incisors of rats and mice may reveal toxicologically significant changes. First, the incisor morphology reflects the nutritional status of the animal: fluctuations of mineral metabolism and vitamin availability are disclosed by the rodent incisors, because the incisors continue to grow during life. Similarly, direct or indirect changes of mineral metabolism by a test substance are reflected in the morphological appearance of the incisor dentin. In addition, hormonal disturbances may give rise to typical structural alterations of the incisor in the test animal. Certain chemicals may have deleterious effects upon the odontogenic tissues, resulting in tooth malformation and malocclusion and eventually in odontomas. Apparent nasal tumors may turn out to be of dental origin. Nasal luminal masses that are discussed within this scope are dental malformation, dental callus, and true odontogenic tumors. According to our experience, odontogenic tumors might possibly develop within the scope of a reaction to mechanical tooth trauma as well. In carcinogenicity studies, this consideration deserves attention when evaluating treatment-related putative odontogenic tumors.

[Impact of antimitotic chemotherapy on the dentition. Apropos of 71 cases]

The authors show the responsibility of antimitotic chemotherapy on the disturbances in dental development in the young children. They insist on doing an odonto-stomatologic check-up at the beginning of the treatment and to keep a constant watch during the treatment and until the end of dental evolution.

Dental properties of antiseptic throat lozenges formulated with sugars or Lycasin

Thirteen different formulations of throat lozenges were examined for their acidity, demineralizing action on hydroxylapatite, and fermentability by human dental plaque micro-organisms. Their flavouring acids gave them low pH values in the range 2.6-3.7, leading to the dissolution of calcium and phosphorus from hydroxylapatite. The combination of antiseptics and flavouring acids in the lozenges inhibited microbial growth and metabolism. In the absence of any antiseptics and flavouring acids, the growth and metabolic activity of cultures of plaque micro-organisms were significantly greater on sucrose+glucose lozenges than on a new Lycasin formulation.

Coronal dentinal nodules induced by single or multiple injections of HEBP in young rats

In the developing tooth, the bisphosphonate HEBP causes hypoplasias and hypomineralization of the enamel and dentine as well as inhibition of acellular cementum formation. Here, we describe a novel effect, associated with dentine mineralization. HEBP was administrated to young rats, and the maxillary molars were analyzed histologically. Localized dentinal nodules, protruding towards the pulp, were found in the developing crown of the molars. They occurred in regions, where the mantle dentine was about to mineralize at the time of the injection, and were more frequent at the mesial cusp side. The nodules accumulated mineral, as evidenced by the fluorescence after calcein and tetracyclin labelling. Histologically, the nodules were separated from the enamel by a layer of mantle dentine and were progressively surrounded by predentine and dentine. The nodules were interpreted to contain transport or metabolism intermediates, which were locally accumulated due to the interruption of the mineralization process by HEBP.

Ankylosis of the mouse molar after systemic administration of 1-hydroxyethylidene-1,1-bisphosphonate (HEBP)

The proposed homeostasis between fibroblasts in the periodontal ligament and bone cells lining the inner aspect of the alveolar wall is thought to be responsible for maintaining the width of the periodontal ligament space. In the present study, we attempted to interfere with this cellular balance by systemic administration of 1-hydroxyethylidene-1,1-bisphosphonate (HEBP). The maxillary left molars of mice were extracted. They then received a daily subcutaneous injection of HEBP (10 mg P/kg b.w.) for periods of 10, 30 or 50 days. A 2nd group of animals received HEBP without molar extraction. Control groups were injected with Ringer's solution. The animals were sacrificed after the last injection and the mandibles processed for light and electron microscopy. HEBP treatment caused a significant decrease of the width of the periodontal ligament space which was influenced by time. Ankylosis started to occur after 30 days, predominantly in the interradicular areas and was more common around unopposed teeth. At 50 days, signs of resorption were seen along the acellular cementum layer. During HEBP-administration, extensive deposition of newly formed cementum matrix was observed along the cellular cementum but this activity was not seen along the acellular cementum. It is concluded that HEBP interferes with the mechanisms that mediate preservation of the periodontal ligament width.

Repair processes in the periodontium following dentoalveolar ankylosis: the effect of masticatory function

It has recently been shown that administration of the drug 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) perturbs the homeostasis in the periodontal ligament resulting in an osteoid-mediated ankylosis between the alveolar wall and the root surface. In the present study, the events after discontinuing HEBP administration were investigated and the effect of function on repair of the periodontal ligament was evaluated. In mice, the maxillary left molars were extracted. They then received a daily subcutaneous injection of HEBP (10 mg P/kg b.w.) for a period of 50 days, were killed 24 h, 14, 28, 56 and 112 days after the last injection and their mandibles processed for light microscopy. HEBP administration caused a significant decrease of the width of the periodontal ligament space with localized ankylosis. In the period after discontinuing HEBP treatment, the newly-formed bone did first mineralize and was then partly resorbed resulting in the disappearance of the ankylotic areas. Furthermore, root resorption was seen. Finally, the periodontal ligament regained its normal architecture and width and a new layer of cementum was formed. Functional teeth showed more root resorption than hypofunctional ones and a more rapid repair of the periodontal ligament. It is concluded that in the period after HEBP treatment the periodontal ligament regains its normal width by a repair process including extensive root resorption, that seems to accelerate this process.

Disturbances in the oral cavity in pediatric long-term survivors after different forms of antineoplastic therapy

Oral health and disturbances in dental development were studied in long-term survivors after antineoplastic therapy. Fifty-seven children treated with combination chemotherapy and 19 children treated with total body irradiation (TBI) prior to bone marrow transplantation (BMT) were examined. The variables studied were dental caries, salivary flow, salivary microbial counts, enamel disturbances, and disturbances in dental development. The results showed no increased caries experience in children treated with BMT or chemotherapy compared with controls. Children treated with BMT had a significantly lower salivary secretion rate of 0.7 +/- 0.4 ml/min, compared with 1.1 +/- 0.5 in the chemotherapy group, and 1.3 +/- 0.6 in the control group (P < 0.05). The clinical examination showed equal numbers of teeth affected by disturbances in enamel mineralization in the BMT and chemotherapy groups. A mean 15.9 +/- 8.2 teeth were affected by disturbances in root development in the BMT group compared with 1.2 +/- 1.6 in the chemotherapy group (P < 0.001). The results show that children who are long-term survivors of pediatric malignant diseases exhibit a wide range of disturbances in the oral cavity. In this study the most severe disturbances are found in children treated with total body irradiation prior to BMT.

Evolution of fluoride concentrations in cattle and grass following a volcanic eruption

This study determined fluoride concentrations of forage, water and bovine serum 2-y after the cessation of a volcanic eruption. Three farms within the polluted area were selected, and water and green grass were collected from April 1990 to February 1992. Samples of hay were collected twice from each farm. Five cows exposed during the 13-mo eruption and 6 young bulls not exposed during the volcanic eruption had blood collected monthly or bimonthly. Serum fluoride concentrations and alkaline phosphatase activities were determined and dental conditions observed in all animals. Grass fluoride remained low except during spring of the second year; high fluoride was in the hay. Serum fluoride of the cows remained near acceptable reference values, although some cows had higher values; serum fluoride of the bulls markedly increased during the spring of the second year. Severe incisor attrition occurred in the cows, while the young bulls had less severely eroded teeth.

[Drug-induced changes in the teeth and mouth. II]

As in the previous paper the unwanted effects of drugs or chemicals in the orofacial region are described. The authors take into consideration alterations such as gingival hyperplasia and hypertrophy, discoloration of the oral mucosa and teeth, oral ulceration and stomatitis, cervical lymphadenopathy, drug induced blood dyscrasias, bleeding caused by aspirin and other drugs, and cleft lip and cleft palate.

Long-term occlusal guidance of a severely intoxicated patient with yusho (PCB poisoning): a case report

The peculiar dentoorofacial characteristics and 12 years of interdisciplinary management of a patient who was severely intoxicated with the man-made chemical polychlorinated biphenyls (PCBs) are described in this case report. Cephalometric measurements showed that the SNA and SNB angles were reduced but that the developments in height and skeletal maturity were in normal ranges. Gingival hyperpigmentation that was caused by high blood PCB concentration was extremely slow to fade. A cystic mass, diffused trabeculae, and irregular calcification, which were shown on the radiograph and which were caused by high blood levels of PCB, changed gradually. However, the patient had periodontal disease because of horizontal alveolar bone resorption and a deep periodontal pocket, despite good plaque control. After the PCB poisoning the tooth roots were hypoplastic and dilacerated. One root was extracted because of chronic periodontitis. Some teeth were impacted, malposed, or ankylosed.

Prevention of dental diseases following radiotherapy and chemotherapy

The general dental practitioner should be aware of the oral changes that take place during chemotherapy and radiotherapy for neoplasms in the head and neck regions. Some of the changes make patients more vulnerable to dental diseases and complications if teeth need to be extracted. Ideally, patients should be made dentally fit before treatment, in order to avoid the risk of extractions later. In the long term, periodontal diseases and caries can be controlled with adequate monitoring and with appropriate use of chlorhexidine and fluoride.

Dentofacial development in long-term survivors of acute lymphoblastic leukemia. A comparison of three treatment modalities

Ninety-seven children who were diagnosed with acute lymphoblastic leukemia before 10 years of age and treated with chemotherapy alone, chemotherapy plus 1800-cGy cranial irradiation (RT), or chemotherapy plus 2400-cGy RT were evaluated for effects of therapy on dentofacial development. All patients were seen at least 5 years postdiagnosis. Dental abnormalities were determined from panoramic radiographs, and craniofacial evaluations were made from lateral cephalometric radiographs. Ninety-one (94%) of all patients and 41 (100%) of patients younger than 5 years of age at diagnosis had abnormal dental development. The severity of these abnormalities was greater in children who received treatment before 5 years of age and in those who received RT. Observed dental abnormalities included tooth agenesis, arrested root development, microdontia, and enamel dysplasias. Craniofacial abnormalities occurred in 18 of 20 (90%) of those patients who received chemotherapy plus 2400-cGy RT before 5 years of age. Mean cephalometric values of this group showed significant deficient mandibular development. The results of this study suggest that the severity of dentofacial-developmental abnormalities secondary to antileukemia therapy are related to the age of the patient at the initiation of treatment and the use of cranial RT.

[Odontostomatological problems in patients with neoplastic pathology treated by chemotherapy. A bibliographic review]

A careful examination of the mouth should be a routine check in patients affected by neoplasms before commencing chemotherapy. This allows an appropriate programme of odontostomatologic treatment to be drawn up and put into practice before, during and after the administration of anti-blastic drugs. Together with instructions for the maintenance of oral hygiene which should be given to the patient, this treatment will reduce the morbidity and mortality which is induced, either directly or indirectly by chemotherapy.

Clinical registration of charge transfer between dental metallic materials in patients with disorders and/or discomfort allegedly caused by corrosion

Thirty referred patients and 15 control subjects were investigated with reference to the occurrence of bimetallic corrosion in the oral cavity. No differences between patients and controls could be found regarding the registered charge transfer between dissimilar short-circuited dental metallic restorations and/or appliances. However, a relatively large number of periodontal and mucous membrane affections, carious lesions and stomatognathic and/or temporomandibular joint disturbances were found within the patient group.

Oral manifestations of systemic chemotherapy and their management

Many antineoplastic drugs in use now have cytotoxic side effects that also manifest in the oral cavity or influence dental management. Chemotherapeutic agents that have a high potential for precipitating oral mucosal damage and bone marrow depression are methotrexate, cyclophosphamide, daunorubicin, doxorubicin hydrochloride, 5-fluorouracil, bleomycin, nitrogen mustard, cytosine-arabinoside, 6-mercaptopurine, busulfan, and L-phenylalanine mustard. Mucositis may lead to neglected oral hygiene, which in turn may cause a chain reaction of local infections, bleeding, and septicemia in myelosuppressed patients. Preventive oral care before chemotherapy and active oral care during therapy are necessary for compromised patients. A protocol for oral care is described.

Tissue reactions to two root canal sealers containing formaldehyde

Tissue reaction to root fillings using either Endomethasone or N2 was investigated in the premolar teeth of dogs. Periapical inflammation was frequently observed, but of greater significance was the universal evidence of ankylosis and the accompanying resorption of teeth filled with N2. One tooth filled with Endomethasone also exhibited this condition. The results of this study do not support the use of these root canal sealers that contain formaldehyde.