La micro-abrasion amélaire associée à l’éclaircissement externe: intérêt dans la prise en charge de la fluorose

La fluorose dentaire est une anomalie de développement qui affecte l'aspect esthétique des dents. L'association de la micro-abrasion à l'éclaircissement externe a montré des résultats satisfaisants pour l'amélioration de l'esthétique des dents atteintes de fluorose légère. L'objectif de ce travail est de mettre le point sur l'intérêt de cette association ainsi que sur ses différents effets sur la surface amélaire.

Interdisciplinary approach to complete-mouth rehabilitation: a clinical report

Dental fluorosis results from excess fluoride ingestion during tooth formation and is commonly seen in certain endemic areas. Its clinical manifestations may range from white opaque patches of enamel in mild cases to pitting and loss of enamel in severe cases. The treatment of fluorosis is important not only because of esthetic and functional concerns but also to help improve a patient's self-esteem; therefore, a multidisciplinary approach is often necessary. This article describes a multidisciplinary approach to complete-mouth rehabilitation of a patient affected with fluorosis. A confluence of the endodontic, periodontal, orthodontic, and prosthodontic disciplines resulted in improved esthetics and enhanced masticatory efficiency.

The analog of Ginkgo biloba extract 761 is a protective factor of cognitive impairment induced by chronic fluorosis

Ginkgo biloba extract EGb761 is widely used to treat patients with learning and memory impairment in Alzheimer's disease and Parkinson's disease in China. However, it is not yet clear whether the analog of EGb761 (EGb) has a protective effect on the learning and memory damage induced by chronic fluorosis. In this study, 30 Wistar rats were randomly divided into three groups: a control group, a sodium fluoride (NaF) + EGb group, and a NaF group. The rats were administered 0.5 ml water containing NaF (100 mg/l) and EGb (120 mg/kg) per day via gavage. After 3 months, the rats' capacity for learning and memory was tested using a Y-maze. Damage to hippocampal neurons was evaluated by histological examination of the CA3 area. Superoxide dismutase (SOD) activity and the levels of glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) were measured. Furthermore, the expression levels of Bcl-2 and Bax and the levels of cleaved Caspase3 in the hippocampus were evaluated by RT-PCR and Western blotting. The results showed that EGb could improve learning and memory abilities, enhance the activities of SOD and GSH-Px, attenuate the level of MDA, upregulate the ratio of Bcl-2/Bax, and downregulate the level of cleaved Caspase3.

Comparison of enamel microabrasion with a combined approach to the esthetic management of fluorosed teeth

OBJECTIVE

To compare in vivo the efficacy of enamel microabrasion alone or in combination with vital tooth bleaching for the management of tooth discoloration caused by fluorosis.

METHODS

A total of 118 maxillary and mandibular fluorosed incisors and canines in 10 patients, scored from 1 to 7 according to the Tooth Surface Index of Fluorosis, were included in this study. All of the teeth were initially treated with enamel microabrasion (Opalustre, Ultradent Products Inc, South Jordan, UT, USA), and after 24 hours, an in-office bleaching technique (Opalescence Boost, Ultradent) was utilized (n=118). Standardized images of the teeth were taken using a digital camera prior to treatment and 24 hours after the enamel microabrasion and after the in-office bleaching therapy. The study groups were assigned according to evaluation time: a) after enamel microabrasion (Group 1) and b) after the combined approach (enamel microabrasion and in-office bleaching) (Group 2). Two calibrated and blinded examiners scored Group 1 and Group 2 images by comparing each with baseline images for "improvement in appearance," "changes in brown stains," and "changes in white opaque areas" using the visual analogue scales (VAS) that range from 1 to 7. "Patient satisfaction," "tooth sensitivity," and "gingival problems" were also recorded. The data were analyzed using two sample paired Wilcoxon signed-rank, Kruskal-Wallis, and Mann-Whitney U-tests (α=0.05).

RESULTS

The combined therapy revealed significantly higher scores than the enamel microabrasion procedure in terms of all of the evaluated criteria (p<0.001). Enamel microabrasion provoked less tooth sensitivity but led to lower patient satisfaction scores than the combined therapy (p<0.001); however, in terms of gingival problems, no differences were found between both groups.

CONCLUSION

The combined therapy, including enamel microabrasion and in-office bleaching, was more effective than enamel microabrasion alone in the esthetic management of fluorosed teeth.

Re-establishing esthetics of fluorosis-stained teeth using enamel microabrasion and dental bleaching techniques

Dental fluorosis manifests itself as white stains on the enamel of teeth exposed to excessive doses of fluoride during their formation. Fluorosis usually occurs as a result of the ingestion of dentifrices, gels and fluoridated solutions. It may be diagnosed as mild, moderate or severe, and in some cases, it may cause the loss of the surface structure of dental enamel. The aim of this study was to report the clinical case of a female patient of 18 years with moderate fluorosis, whose smile was reestablished by the use of an enamel microabrasion technique, followed by in-office bleaching. A microabrasion technique with 6% hydrochloric acid associated with silica carbide showed to be a safe and efficient method for removing white fluorosis stains, while dental bleaching was useful for obtaining a uniform tooth shade. The association of these techniques presented excellent results and the patient was satisfied. Both techniques are painless, fast and easy to perform, in addition to preserving the dental structure. Treatment showed immediate and permanent results; this technique must be divulged among professionals and their patients.

Dental whitening--revisiting the myths

The popularity of dental bleaching has increased with the introduction of at-home whitening. Currently available whitening methods include those prescribed by a dental professional for use at home, those applied by the professional in the dental office, a combination of the two, or systems available over the counter. This article reviews the effect, efficacy, and safety of bleaching techniques and materials. Most whitening techniques are considered effective and safe when carried out under the supervision of a dental professional. This article also compares the efficacy and safety of some of the most popular bleaching techniques, including at-home whitening with carbamide peroxide, over-the-counter (OTC) systems, and in-office whitening. Some of these whitening techniques are illustrated in this article.

Why does fluorosed dentine show a higher susceptibility for caries: an ultra-morphological explanation

BACKGROUND

Chronic endemic dental fluorosis is a malformation of teeth caused by excessive ingestion of fluoride during period of tooth development. Apatite crystallites and collagen fibrils determine the caries susceptibility related properties of dentine. Information relating the effect of dental fluorosis with dentine crystallite and collagen structure is currently unavailable. This study examined structural aberrations of apatite crystallites and collagen fibrils in human fluorosed dentine.

METHOD

Superficial dentine of thirty six normal (Thylstrup-Fejerskov index - 0) and thirty six severely fluorosed (Thylstrup-Fejerskov index - 7 to 9) extracted human molars from individuals living in an area which is endemic for dental fluorosis were morphologically analyzed using transmission electron microscopy with selected area electron diffraction and dynamic force microscopy.

RESULTS

A statistically significant enlargement in the size of crystallites was found in fluorosed dentine (p<0.05). These crystallites were not homogenously arranged. Selected area electron diffraction revealed a lower density of crystallites in fluorosed dentine. Randomly distributed collagen fibrils showed a less complex lay out in contrast to normal dentine tissue.

CONCLUSION

Ultrastructure aberrations of the dentine explain the caries susceptibility of the tissue and suggest the necessity of special approach in dental caries treatment for patients with chronic severe endemic dental fluorosis.

Association of enamel microabrasion and bleaching: a case report

Enamel microabrasion may be indicated for certain clinical situations, since it is a proven method for removing superficial intrinsic enamel discoloration defects such as fluorosis-like stains; in addition, it is safe, conservative, and easy to perform. However, this method removes enamel structure, causing teeth to become yellowish. This yellowing can be treated with enamel microabrasion and bleaching. This article describes and documents how these two methods were utilized to correct tooth color for a young patient.

A randomized CIE L*a*b* evaluation of external bleaching therapy effects on fluorotic enamel stains

OBJECTIVE

To evaluate the effect of external bleaching on the color and luminosity of fluorotic stains and adjacent, normally mineralized enamel areas by means of CIE L*a*b* colorimetry.

METHOD AND MATERIALS

Eighteen adolescents with mild to moderate fluorotic stains were randomly assigned to either bleaching group A (n = 9) or control group B. Eligibility criteria were fluorotic stained maxillary incisors or canines and the informed consent of the participants and their guardians. Using a colorimeter, CIE L*a*b* values of maxillary incisors and canines were assessed at baseline (T1) in the center of the fluorotic stained area (F1) and at adjacent, normally mineralized enamel areas (F2). Then, external bleaching with Illumine office (30% hydrogen peroxide, Dentsply DeTrey) was performed for 60 minutes, followed by color reassessment (T2). After 14 days (T3), a 2-week home bleaching period with a daily bleaching time of 1 hour with Illumine home (15% carbamide peroxide, Dentsply DeTrey) was conducted with subsequent color determination (T4).

RESULTS

After completion of bleaching therapy, 96.0% of all fluorotic areas (F1) and 100% of normal enamel areas (F2) showed a significant change within group A, compared to 29.4% in control group B. Comparing the collective DeltaE (L*, a*, b*) of F1 and F2, 60.0% of all areas showed significant differences after completion of bleaching therapy, compared to 88.0% initially. Of group B sites, 82.4% showed color differences in the beginning (T1) and 88.2% at the end (T4).

CONCLUSION

Whereas a single 1-hour session of in-office bleaching with 30% hydrogen peroxide does not significantly affect the color and luminosity of fluorotic teeth, a 14-day period of home bleaching leads to an assimilation of the color of the fluorotic stain with the color of surrounding enamel areas due to different responses of sound and fluorotic enamel to the bleaching regime.

An overview of tooth discoloration: extrinsic, intrinsic and internalized stains

The causes of tooth discoloration are varied and complex but are usually classified as being either intrinsic, extrinsic or internalized in nature. Dietary chromogens and other external elements deposit on the tooth surface or within the pellicle layer either directly or indirectly to form extrinsic discoloration. Stains within the dentine or intrinsic discoloration often results from systemic or pulpal origin, while internalized stains are the result of extrinsic stains entering the dentine via tooth defects such as cracks on the tooth surface.

Factors associated with parents' esthetic perceptions of children's mixed dentition fluorosis and demarcated opacities

PURPOSE

With the increasing prevalence of dental fluorosis, improved understanding about esthetic perceptions of dental fluorosis is warranted. The purpose of this report was to present results concerning parents' overall satisfaction with the appearance of their children's teeth and factors related to dissatisfaction, comparing subjects with and without fluorosis and demarcated opacities.

METHODS

Data were obtained from 577 parents in the Iowa Fluoride Study who answered a questionnaire concerning their satisfaction with the appearance of their children's teeth at age 9 years, as well as several components of dissatisfaction. Concurrent assessment of the mixed dentition was made by 1 of 2 trained dentist examiners.

RESULTS

Overall, 31% of parents were very satisfied, 51% somewhat satisfied, 16% somewhat dissatisfied, and 3% very dissatisfied with appearance. Parents of children without fluorosis were more likely to be very satisfied (46%) than were parents of children with questionable fluorosis (31%) or definitive fluorosis (22%). Among the 401 not "very satisfied," 50% of those with fluorosis vs 40% with no fluorosis were concerned about color, 60% of both groups were concerned about alignment, 44% and 51%, respectively, were concerned about crowding, and 44% and 9%, respectively, were concerned about blotchiness.

CONCLUSIONS

Fluorosis was associated with increased parental dissatisfaction with overall appearance, color, and blotchiness of their children's teeth.

Using microabrasive material to remove fluorosis stains

BACKGROUND

Increased public access to fluoride has decreased the prevalence of caries and increased the prevalence of fluorosis staining. This article provides a case report involving a conservative method of removing fluorosis stain, as well as describes an in vitro test of the method.

CASE DESCRIPTION

A healthy man sought treatment at New York University College of Dentistry for removal of severe, dark brown fluorosis staining on his anterior teeth. To remove the stain, the treating clinician used a microabrasive material, which leaves enamel intact, instead of a tooth-whitening agent, which requires removal of all affected enamel.

METHODS

To demonstrate that enamel structure is not disturbed by the microabrasive material, the authors performed a study using scanning electron microscopy, or SEM. They viewed enamel structure under SEM at x1,000 magnification. They viewed untreated microabraded enamel and compared it with enamel that had been treated for 20 seconds with 37 percent phosphoric acid.

RESULTS

An etch pattern was not discernible on the tooth treated with the microabrasive material. The enamel prisms remained intact and the cores were not exposed.

CLINICAL IMPLICATIONS

Microabrasion removes intrinsic fluorosis stain effectively while protecting enamel. In this case, an enamel shade of brown not in the range of any tooth color shade guide was reduced.

Effectiveness of treatment with carbamide peroxide and hydrogen peroxide in subjects affected by dental fluorosis: a clinical trial

Dental fluorosis is an endemic dental health problem around the world; so, it is important to develop clinical alternatives that are non-invasive and inexpensive. In this study, nightguard vital bleaching technique (NVBT), using carbamide and hydrogen peroxide as active agents, has shown itself to be effective in whitening teeth affected by dental fluorosis. Carbamide peroxide at 10 and 20% and hydrogen peroxide at 7.5% showed good clinical effectiveness in improving clinical appearence, but it is important to point out that clinical success is only in cases of class 1 to 3 of the Tooth Surface Index of Fluorosis. When comparing 10 and 20% concentrations of carbamide peroxide, there was no difference in the clinical effectiveness (p > 0.05); but when comparing both concentrations of carbamide peroxide against hydrogen peroxide, results showed that carbamide peroxide was more effective in whitening in cases of dental fluorosis, the difference being statistically significant (p < 0.05). NVBT has two advantages: it is a non-invasive technique and the relationship cost/benefit is excellent; only a few patients reported tenderness or mild tooth sensitivity.

Treatment of endemic fluorosis and tetracycline staining with macroabrasion and nightguard vital bleaching: a case report

A patient, diagnosed with a combination of level 3 endemic dental fluorosis and degree 1 tetracycline staining, was treated sequentially by macroabrasion techniques and nightguard vital bleaching. Various pairings of diamond and carbide burs, abrasive disks, rotary polishing points, and diamond polishing pastes were tested to obtain the optimal combination for macroabrasion. This conservative treatment regimen produced results that were termed "excellent" by the patient and met the goals of the dentists.

Dental caries and developmental defects of enamel in relation to fluoride levels in drinking water in an arid area of Sri Lanka

The study was conducted to assess caries and developmental defects of enamel in relation to fluoride levels in drinking water and the association between caries experience and the severity of diffuse opacities in children living in Uda Walawe, an area with varying concentrations of fluoride in drinking water in Sri Lanka. A total of 518 14-year-old children who were lifelong residents in this area were examined for dental caries and developmental defects of enamel. But the present analysis is confined to 486 children from whom drinking water samples were collected. The prevalence of enamel defects and diffuse opacities ranged from 27 to 57% while the prevalence of caries ranged from 18 to 29% in the different fluoride exposure groups. The prevalence of enamel defects increased significantly with the increase in the fluoride level in drinking water. Both the caries prevalence and the mean caries experience were significantly higher in children with diffuse opacities than in those without in the group consuming water containing >0.70 mg/l of fluoride. The association between dental caries and the severity of diffuse opacities was also significant only in this group. Children with the mildest form of opacities (DDE scores 3 and 4) had the lowest DMFS (0.25 +/- 0.7), and the highest DMFS (1.1 +/- 1.7) was found in those with the most severe form of opacities (DDE score 6). In conclusion, the relationship that was observed in this study between fluoride levels in drinking water, diffuse opacities and caries suggests that the appropriate level of fluoride in drinking water for arid areas of Sri Lanka is around 0.3 mg/l. Also individuals with severe forms of enamel defects in high-fluoride areas are susceptible to dental caries.

Endemic fluorosis in Rajasthan

Chronic fluoride (F) toxicity in the form of osteo-dental fluorosis was observed in both sexes of children and adults from ten villages viz., Bhavanpura, Dovada, Genhuwara, Gokulpura, Hathai, Kahela, Mandav, Nalwara, Pratappura and Samota located in the vicinity of alive F mines of Dungarpur district (Rajasthan) where F concentration in drinking waters varied from 1.2 to 8.9 ppm. At 1.7 and 6.1 mean F concentrations, 70.6% and 100.0% of children (< 18 years) and 68.0% and 100.0% adults, respectively, were found to be affected with dental fluorosis of varying grades. No much sex difference was seen in prevalence of dental fluorosis. Both prevalence and severity of dental mottling were found to be increased with increasing of F concentration and were found maximum in the 17-22 years age group. At these same F concentrations, 7.4% and 37.7% adults (> 21 years) were showing evidence of skeletal fluorosis, respectively. Although, skeletal fluorosis was also found in children with low prevalence (5.2%) but at high F concentration (4.8 ppm). The prevalence of skeletal fluorosis was relatively higher in males and increased with higher F level and age. Deformities such as crippling, kyphosis, invalidism and genu-varum were observed frequently in higher age group subjects (> 48 years) at a F concentration of 3.3 ppm. None of fluorotic individuals revealed evidence of genu-valgum syndrome and goitre (thyroidism). Radiological findings of other deformities in fluorotic subjects were also found. The distribution of F and endemic fluorosis in different districts of Rajasthan state have also been reviewed.

Endemic fluorosis in Turkish patients: relationship with knee osteoarthritis

Fluoride excess primarily effects dental and skeletal tissues. leading to a condition known as endemic fluorosis. The radiological and clinical features of endemic fluorosis vary in different parts of the world. The aim of this study was to investigate the clinical and radiological features of endemic fluorosis in Turkish patients. Physical examination and radiological investigations were performed in 56 patients with endemic fluorosis and 40 age- and sex-matched controls. Knee osteoarthritis (OA) was the main abnormality in both groups, both clinically and radiologically. The radiological severity of knee OA was greater in the endemic fluorosis group than in controls (P=0.01). Osteophytes at the tibial condyles and superior margin of the patellar articular surface of the femur, polyp-like osteophytes on the non-weight-bearing medial side of the femoral condyle, and popliteal loose bodies were detected more frequently in the endemic fluorosis group than in controls (P=0.0001). We suggest that the presence of atypically located osteophytes in the knees may be a feature of endemic fluorosis in Turkish patients and that endemic fluorosis may increase the severity of OA in the knees.

Tooth discolouration and staining: a review of the literature

OBJECTIVE

To carry out an extensive review of the literature on tooth staining with particular regard to some of the more recent literature on the mechanisms of tooth staining involving mouthrinses.

DESIGN

Comprehensive review of the literature over four decades.

CONCLUSIONS

A knowledge of the aetiology of tooth staining is of importance to dental surgeons in order to enable a correct diagnosis to be made when examining a discoloured dentition and allows the dental practitioner to explain to the patient the exact nature of the condition. In some instances, the mechanism of staining may have an effect on the outcome of treatment and influence the treatment options the dentist will be able to offer to patients.

The current status of vital tooth whitening techniques

Tooth whitening of vital teeth continues to have a major impact on the practice of dentistry. The growing public interest in having whiter, brighter teeth is clearly evident in the advertisements from toothpaste manufacturers on "whitening" formulations of their products and by the number of individuals seeking whitening procedures from their dentists. In addition, new over-the-counter whitening products continue to emerge in a marketplace that cannot seem to get teeth white enough, bright enough, fast enough. What new products and procedures have evolved over the past decade to whiten teeth? Are they better, safer, faster, and more effective now? Are dentists meeting public demand for whiter teeth and is this quest having a positive or negative impact on the practice of dentistry or the patient's dental health? I posed these questions to a group of experts on whitening procedures to get their opinions and recommendations.

Oral hygiene as a risk indicator of enamel and dentin caries

Dental researchers have postulated that the risk factors for enamel and dentin caries may not be the same. A review of the literature ascertained that data to support this theory are lacking.

OBJECTIVES

To evaluate the risk indicators of enamel and dentin caries of the permanent dentition in a study group who had limited access to fluorides and made limited use of dental services.

METHODS

The study was conducted in Goa, India. Data came from a cross-sectional survey of 1189 seventh grade children, which consisted of a clinical dental examination and a self-administered questionnaire to their parents. The cavitated and non-cavitated criteria were used to score for caries, and the Silness-Loe index for plaque.

RESULTS

The mean age of the children was 12.2 years. The percentage of children caries free in the permanent dentition was 22.2%, the mean+/-s for dmfs, enamel and dentin lesions were 4.20+/-5.10, 2.59+/-2.89 and 1.61+/-3.30 respectively, and the mean plaque score was 1.00+/-0.48. Results of regression analyses showed that the risk indicators of prevalence and severity of caries differed depending on lesion type. The only variable that was consistently a risk indicator of presence and severity of both dentin and enamel caries was poor oral hygiene. Mother's highest level of education and presence of fluorosis were also risk indicators of enamel and dentin caries. The presence of decayed primary teeth was a risk indicator of enamel caries; and fluorosis severity, use of fluoride toothpaste at the time of the survey, and toothbrushing frequency were risk indicators of dentin caries. The observed caries-oral hygiene association seen is explored further.

A successful combination of conflicting approaches to diastema closure--a case report

The closure of anterior maxillary diastemas can be accomplished in several ways. A case is reported where treatment initially consisted of the provision of porcelain laminate veneer restorations, with an unsatisfactory result. Subsequently, the restorations were reduced drastically in width and reshaped. The tooth widths were calculated from tables of mean measurements. The spaces were closed by orthodontic treatment and the original restorations were retained, saving the patient considerable treatment.

The effectiveness of a modified hydrochloric acid-quartz-pumice abrasion technique on fluorosis stains: a case report

Endemic dental fluorosis is a form of enamel hypoplasia characterized by moderate-to-severe staining of the tooth surface. Since 1916, numerous investigators have used hydrochloric acid alone on fluorosis stains. More recently, 18% hydrochloric acid-pumice microabrasion has been used to achieve color modification. The main disadvantage of this procedure is the high concentration and low viscosity of hydrochloric acid, which can cause damage to oral and dental tissues. To eliminate this problem, quartz particles can be mixed with the hydrochloric acid. The quartz particles prevent the hydrochloric acid from flowing uncontrollablely by altering it to a gel-like form. A modified 18% hydrochloric acid-quartz-pumice abrasion technique was used to remove fluorine stains from vital teeth in a teenager.

Dental erosion associated with soft-drink consumption in young Saudi men

This study reports on the causative factors of dental erosion in selected high- (n = 19) and low-erosion (n = 19) subgroups of a larger random sample (n = 95) of young male Saudi military inductees. By means of a questionnaire, the role of various possible factors related to oral health in general, and to dental erosion in particular, was assessed for each participant. Clinical examination included recordings of severity of dental erosion and fluorosis, presence of buccal cervical defects and first permanent molar 'cuppings', DMFT and DMFS, visible plaque index, and gingival bleeding index. In addition, bitewing radiographs, study casts, and intraoral color transparencies were obtained for each individual. Logistic regression analysis showed a strong correlation between the presence of dental erosion and a high level of consumption of cola-type soft drinks. Other statistically significant associated factors, although of less predictive strength, were type of cleaning aid and gingival bleeding index. In subgroup comparisons, dental problems (primarily pain), number of buccal cervical defects, and number of missing teeth were significantly greater in the high- than in the low-erosion subgroup.

Megabrasion: a conservative strategy for the anterior dentition

Continuous developments in adhesive restorative techniques, tooth whitening procedures, and restorative materials have significantly broadened the initially defined spectrum of indications for composite restorations. These developments have thereby contributed to the achievement of one of the major objectives of conservative restorative dentistry--the maximum preservation of sound tooth structure. In order to optimize the application of modern composite resin technology, mastering the basic principles of natural aesthetics is an essential prerequisite. The learning objective of this article is to discuss the etiology of enamel discoloration and conservative treatment strategies, including microabrasion and masking procedures. Emphasis is placed on a simple procedure--the megabrasion technique--which does not depend extensively on the artistic skills of the operator. It represents a useful and predictable approach for the elimination of white opaque stains on the enamel and yellow-brown enamel discolorations.

In-office bleaching: where we came from, where we are today

Discolored teeth are the primary aesthetic concern among dental patients. While many seek professional advice and treatment, an alarming number opt for non-professional quick-fix solutions. The in-office bleaching modality often is overlooked in favor of at-home vital bleaching. But this option has been proven to be effective, quick and safe-either alone or in combination with other aesthetic treatments-as a method of brightening and enhancing a patient's smile.

Endemic fluorosis

The presence of excessive quantities of fluorine in drinking water is accompanied by a characteristic sequence of changes in teeth, bone and periarticular tissues. These changes lead to a variable degree of locomotor disability, ranging from simple mechanical back pain to severe, crippling, combined locomotor and neurological impairment. In endemic areas, a substantial proportion of the population may be affected, posing a severe public health problem. In some areas, the hazards to human health are not fully appreciated and are under-reported. The maximum impact is felt in those communities engaged in physically strenuous activities, either agricultural or industrial. The need of these often isolated communities in economically hard-pressed countries, for the provision of low-fluoride drinking water remains a hope rather than an expectation at the present time.

[Canal preparation of fluorotic teeth]

This study compared the effectiveness of nine root-canal preparation techniques of fluorotic teeth. Seventy-three canal systems from 53 extracted human fluorotic teeth were instrumented. Pre-and postinstrumentation measurements were taken of the root canal systems in the cervical, middle and apical thirds; they proved the efficiency of the method using Rispi and Helifile. The results of this study were also extrapolated to the clinical situation.

Relationship of dental caries and fluorosis to fluoride supplement history in a non-fluoridated sample of schoolchildren

A random sample of 206 Michigan children, aged from 9 to 13, were examined for fluorosis from a larger group of 2038 children participating in a dental project. Clinical examinations included caries data (DMFS) and assessment of fluorosis by use of the Tooth Surface Index of Fluorosis (TSIF). Separate examiners were used for each index. The response rate of a questionnaire mailed to parents to gather information on residence histories, use of fluoride supplements, and antibiotics was 78%. The prevalence of fluorosis was about 20% among the respondents. Of the 4868 tooth surfaces examined, 9.2% were affected by fluorosis. In all cases, dental fluorosis was judged as mild, with most occurrences on the posterior teeth. No instances of moderate or severe fluorosis were found. The caries experience of respondents was 1.69 +/- 2.73 DMFS. Caries experience does not appear to be significantly related to income, education, or fluoride supplement use. Approximately 52% of respondents were reported to have taken fluoride supplements with various degrees of consistency. Parents' education was positively related to both prevalence of fluorosis (odds ratio = 2.2) and use of fluoride supplements (odds ratio = 2.7). No significant relation was revealed with evidence of fluorosis and use of supplements. This study shows a relatively mild level of dental fluorosis in a sample of children from a non-fluoridated area. Dental fluorosis in this group does not appear to be related to use of fluoride supplements or differences in caries experience.

Endemic fluorosis presenting as cervical cord compression

Neurological involvement in fluorosis occurs in the advanced stage of the disease and is due to compression of the spinal cord and/or nerve roots. There are only a few reports on the role of surgical management of these cases in the medical literature. Five cases of fluorosis from the endemic areas of Uttar Pradesh, India, had associated cervical cord compression. Their mean age was 43 yr (range 35-50), and all cases were manual laborers. Three patients with blocked cervical subarachnoid space on myelography underwent laminectomy using local anesthesia. All three cases improved significantly after surgery. The usefulness of laminectomy in selected cases of cervical cord compression due to fluorosis is suggested.

Systematic assessment of color removal following vital bleaching of intrinsically stained teeth

Various treatment variables associated with a standard bleaching technique were systematically recorded in 53 individuals exhibiting intrinsic discoloration of permanent teeth. These variables (predictors) included: (1) etiology (fluoride or tetracycline); (2) age of the patient; (3) the presented color of the stain; (4) the intensity of that color; (5) a long versus short bleaching time technique; and (6) the number of bleaching sessions. These were assessed as to their relationship with the results of treatment (dependent variable). The findings of a multiple regression analysis revealed that the contributions of the individual predictors were significantly different between those stains caused by tetracycline ingestion (N = 27) and those stains due to fluoride ingestion (N = 20). The analysis also revealed that those variables contributing to a significant proportion of the variance in results of treatment when tetracycline was the cause were: (1) the color of the stain and (2) the number of bleaching sessions. When fluoride was apparently the causal agent: (1) the bleaching time technique; (2) age of the patient; (3) color of the stain; and (4) the number of bleaching sessions contributed to a significant proportion of the variance in the results of treatment.

Neurosurgery in India

This is a brief account of Neurosurgery in India. Prior to 1949, Neurosurgery was being practised by General Surgeons. With the return of Professor Jacob Chandy to the Christian Medical College, Vellore in 1949 modern neurosurgery was born and progressed, and today there are more than 180 neurosurgeons in India. Even so, the ratio works out to one neurosurgeon for every 3,600,000 individuals! Conditions commonly encountered such as hydrocephalus, craniovertebral anomalies, pyogenic, fungal and tuberculous infections of the central nervous system, and fluorosis are being discussed. Stereotaxic surgery for pain, epilepsy, behaviour disorders and involuntary movements is being practised at several centres especially at Madras. Following the workshops conducted by Professor Pia and his co-worker Professor Grote , enthusiasm for microneurosurgery has waxed.

Dental fluorosis associated with hereditary diabetes insipidus

Among the characteristics of hereditary pituitary diabetes insipidus are polydipsia and polyuria from early infancy. Drinking of large amounts of water, even with lower than accepted fluoride content, can produce fluorosis of the teeth. A mother and her four children affected by this disorder presented different degrees of fluorosis directly related to the stage at which hormonal therapy was introduced.

Clinical evaluation of the sandpaper disk method for removing fluorosis stains from teeth

The sandpaper disk method for removing fluorosis stains from teeth was clinically evaluated in 93 teeth in 22 patients. A bleaching solution was first applied to the teeth, and then a sandpaper disk in a straight handpiece was rotated on the stained enamel surface. None of the patients complained of discomfort during or after the bleaching procedure.