Molar incisor hypomineralization: Analysis of asymmetry of lesions.

Clinically, Molar-Incisor Hypomineralization (MIH) lesions are not distributed symmetrically, and their severity varies even within the same arcade. AIM: To estimate the frequency of asymmetries in hypomineralized lesions on permanent molars and incisors of children with MIH. METHODS: Three pediatric dentists, calibrated following the diagnostic criteria of Mathu-Muju and Wright (2006) (Kappa 0.87) identified presence and severity of opacities on molars and incisors of patients with MIH. Six pairs of teeth (permanent maxillary and mandibular first molars, central and lateral incisors) were evaluated in each patient. Degree of lesion severity (0-none, 1-mild, 2-moderate, 3-severe) was recorded for each tooth. For each pair containing any affected teeth, asymmetry of presence (one tooth in the pair with lesion and the other intact), asymmetry of severity (both teeth with lesions but with different degrees of severity) or symmetry of severity (both affected teeth with the same degree of severity) were evaluated. The recorded values were entered into a database to calculate percentages, 95% confidence intervals and Chi-Square test for comparisons. RESULTS: The sample consisted of475 of the 1032 pairs of teeth evaluated in the 172 patients included in the study, mean age 11±2.2 years, and 50% female. Asymmetry was found for 67.5% (63.1 - 71.7) of the pairs of the studied teeth. There was a significant relationship between asymmetries and symmetries (p=0.038). A total 50.1% of the pairs were asymmetrical for presence of opacities. Of these, 62.2% scored severity 1 (mild). Symmetry of severity was found for 32.5% of the lesions. Among the pairs of affected teeth, the most frequently observed degrees of lesion severity were mild and moderate, with the exception of lower molars, in which 49% had severe lesions. CONCLUSIONS: In this study, MIH lesions were asymmetrical both in presence and severity for all tooth types.

Clínicamente las lesiones de Hipomineralización Molar Incisiva (HMI) no tienen una distribución simétrica variando su severidad inclusive en la misma arcada. Objetivo: Estimar la frecuencia de asimetrías en lesiones de hipomineralización en molares e incisivos permanentes de niños afectados con HMI. Métodos: Tres odontopediatras calibrados (Kappa 0,87) según los criterios de diagnóstico de Mathu-Muju y Wright (2006), registraron presencia y severidad de opacidades en molares e incisivos de pacientes con HMI. En cada paciente se evaluaron 6 pares de piezas dentarias permanentes: primeros molares, incisivos centrales y laterales de ambos maxilares. Para cada una de las piezas se registró el grado de severidad de la lesión (0-intacto, 1-leve, 2-moderado, 3-severo). Para cada par con alguna de sus piezas afectadas, se analizó si presentaba asimetría de presencia (una pieza del par con lesión y la otra intacta), asimetría de severidad (ambas piezas con lesión pero con distinto grado de severidad) o simetría (ambas piezas afectadas con el mismo grado de severidad en la lesión). Se calcularon porcentajes, I.C. del 95% y CHI2 para las comparaciones. Resultados: La muestra quedó conformada por los 475 pares de piezas dentarias que presentaron lesión entre un total de 1032pares de piezas analizadas en los 172 pacientes incluidos en el estudio (edad media 11 ± 2,2 años, 50% género femenino). El 67,5% (63,1- 71,7) de los pares de piezas dentarias estudiados presentaron relación de asimetría. La relación entre frecuencia de asimetrías y simetrías fue significativa (p= 0,038). Del 50,1% de los pares que presentó asimetrías en presencia, un 62,2% mostró grado de severidad 1(leve) en una de sus piezas. Entre los pares afectados, las lesiones leves y moderadas fueron las más observadas en todos los grupos dentarios, a excepción de los molares inferiores que revelaron un 49% de lesiones severas. Conclusiones: En este estudio las lesiones de HMI presentaron, en su mayoría, algún tipo de asimetría (de presencia o de severidad) en todos los grupos dentarios.

The prevalence and morphological types of non-carious cervical lesions (NCCL) in a contemporary sample of people.

Non-carious cervical lesions (NCCLs) were examined in 6541 extracted human teeth and classified based on the morphology of the lesions. As a result, NCCLs were found on 38.7% of teeth (41.6% on maxillary teeth and 36.0% on mandibular teeth), and were most frequent on canines and first premolars. According to the new method of classification, the morphology of NCCLs was classified both by the surface contour (SC) and by the cross-sectional contour (CC). Three types of NCCLs appeared to be dominant. The causes of these NCCLs were discussed based on their morphologies, positions where these NCCLs were frequently found, and the results of previous studies. NCCLs with a horizontal oval SC and a round CC (Type I), which were frequent on the labial surfaces of maxillary canines and buccal surfaces of maxillary first premolars, may be associated with wear by friction and chemical degradation. NCCLs with a vertical oval SC and a round CC (Type II), which were frequent on the lingual surfaces of mandibular incisors and canines, might be mainly related to chemical degradation. NCCLs with a horizontal oval SC and a wedge shape CC (Type III), which were extensively found on the buccal surfaces of maxillary premolars, had formed most probably due to wear by friction and microstructural loss by stress. This new method can classify the morphology of NCCLs more precisely and deduce the mechanisms of the formation of NCCLs more clearly than former methods.

Orthodontics and enamel demineralization: clinical study of risk factors.

UNLABELLED: The appearance of white spots on the vestibular surface of teeth fitted with brackets has been described as one of the potential iatrogenic effects of orthodontic treatment. These enamel demineralizations, more commonly known as "white spot lesions" (WSL), lead in some rare cases to the creation of true cavities, causing both esthetic and functional problems. The aim of our retrospective clinical study was to evaluate the incidence of the appearance of these WSL in a Moroccan orthodontic population and to determine possible associations with a number of risk factors. PATIENTS AND METHODS: The study was based on intraoral photographs of a pool of 69 patients who underwent orthodontic treatment with or without extractions in the DFO unit of the Rabat CCDT (Center for dental consultation and treatment). Patients with prostheses or WSL before the beginning of the study were excluded. Digital start- and end-of-treatment photos for each patient were compared by a single operator looking for the appearance of WSL on the vestibular surfaces of the incisors, canines, premolars and first molars. WSL were classed according to three degrees of severity: slight, severe and cavitation. Data were processed using SPSS 13.0 software. RESULTS: The results of the study showed that the prevalence of WSL in the sample was 66.7%, with a highly significant predominance of localization in the premolar/molar segment and in patients with poor oral hygiene. CONCLUSION: Poor oral and dental hygiene was identified as the most important risk factor for the development of white spots during multibracket orthodontic treatment.

Assessment of non-cavitated and cavitated carious lesions among 12- to 15-year-old government and private school children in Pune, Maharashtra, India.

PURPOSE: The present cross-sectional study was conducted to assess and compare the mean number of non-cavitated (initial lesions, IL) and cavitated carious lesions (WHO criteria) per child in the permanent dentition and to correlate it with the plaque index among 12- to 15-year-old government and private school children. MATERIALS AND METHODS: 481 schoolchildren aged 12-15 years were selected randomly by multistage random sampling from two government and two private schools. Demographic details were collected at the time of examination. Baseline plaque scores were recorded using the Silness and Löe plaque index. Immediately after brushing and drying the teeth, cavitated lesions were recorded based on WHO recommendations and non-cavitated lesions were recorded using the IL criteria of Nyvad et al and Fyffe et al. RESULTS: The mean number of surfaces with cavitated and non-cavitated lesions for government school children was 2.13 ± 2.98 and 3.21 ± 2.97, respectively, and 1.24 ± 1.86 and 3.08 ± 2.33 for private school children, respectively. WHO + IL surfaces among private school children were 4.33 ± 3.48 and in government school children 5.35 ± 4.45. There was a positive correlation of plaque score with IL (r = 0.63) and WHO+IL (r = 0.73). CONCLUSION: Non-cavitated lesions are about twice as common as cavitated carious lesions in school children. Government school children had a higher number of cavitated and non-cavitated carious lesions when compared with private school children.

Prevalence of dental fluorosis among primary school children in rural areas of Karera Block, Madhya Pradesh.

OBJECTIVE: To determine prevalence and severity of dental fluorosis in school going children of ten villages of Karera block of Shivpuri District, Madhya Pradesh. METHODS: Fluoride ion concentration was measured in ten hand pump and two wells waters with a fluoride meter (ORION model 720). For the study total 750 school children were selected from ten government primary schools of ten rural villages. The survey was conducted during the period of November 2007 through December 2009. The dental and oral examination was done by two trained dentists. The occurrence and severity of dental fluorosis was recorded using Dean's index. RESULTS: Drinking water sources considered for study were hand pumps, and wells. Out of 750 children surveyed, 341 were found affected with dental fluorosis. The boys had greater prevalence (46.75%) as compared to girls (42.18%). Dental fluorosis, as assessed by Dean's Index shows that 20.8% children had grade I, 19.47% grade II, 5.2% grade III. Overall, 45.46% of the sample showed some grades of dental fluorosis. CONCLUSIONS: In all the 144 water samples from ten villages fluoride level was higher than permissible limits. The boys had greater prevalence of dental fluorosis over the girls.

Effectiveness of a sealant compared with no sealant in preventing enamel demineralization in patients with fixed orthodontic appliances: a prospective clinical trial.

INTRODUCTION: In this study, we tested the efficacy of a tooth sealant polish (Biscover LV; Bisco, Schaumberg, Ill) to prevent enamel demineralization (white spot lesions) for the full duration of orthodontic treatment with fixed appliances. The trial design was an alternating-tooth split-mouth design. METHODS: Patients starting treatment with bonded appliances in a private practice were enrolled. The 6 maxillary anterior teeth received the test sealant or no sealant. The nonblinded orthodontists visually examined the teeth immediately after debonding and rated the presence and severity of white spot lesions using a 4-point scale. The difference in incidence of white spot lesions on treated and control teeth was tested with multivariate binary logistic regression for repeated measures by using the generalized estimating equations approach. RESULTS: Sixty-five subjects were enrolled, and 3 were lost to follow-up, leaving 62 for analysis. There was a slightly lower incidence of white spot lesions on treated teeth (13.5%; 95% confidence interval, 8.6-18.4) compared with the control teeth (17.7%; 95% confidence interval, 12.4-23.7). This difference was statistically significant in the multivariate model (Wald chi-square, 5.07; df = 1; P = 0.024). The odds ratio was equal to 0.68 (95% confidence interval, 0.47-0.95) that treated teeth would show white spot lesions relative to the control teeth. White spot lesion severity was nearly the same for treated and control teeth (mean ± SD = 1.17 ± 0.47 and 1.20 ± 0.48, respectively; Wald chi-square, 3.03; df = 1; P = 0.082). No serious adverse effects were reported. CONCLUSIONS: The sealant did not prevent all white spot lesions for the full duration of treatment. The sealant demonstrated a clinically small but statistically significant ability to prevent white spot lesions.

Prevalence of demarcated hypomineralisation defects in second primary molars in Iraqi children.

BACKGROUND: Demarcated hypomineralization lesions are not uncommon in second primary molars. Data on the prevalence of hypomineralized second primary molars (HSPM) are scarce. AIM: To investigate the prevalence of HSPM, assess the relationship between HSPM and first permanent molars previously diagnosed with demarcated lesions and to determine the severity of HSPM in relation to dental caries severity. DESIGN: A cluster sample of 809, 7- to 9-year-old children was examined. The scoring criteria proposed by the European Academy of Paediatric Dentistry for hypomineralization in permanent dentition were adapted to score HSPMs. The International Caries Detection and Assessment System was used to assess caries status in the second primary molar of the children diagnosed with demarcated defects. The examination was carried out in schools by a calibrated dentist. RESULTS: Of the children examined, 53 (6.6%) had hypomineralization defects in at least one second primary molar. Combinations of affected first permanent and second primary molars were reported in 21 (39.6%) of cases. Severe carious lesions were found mostly in teeth with enamel breakdown. CONCLUSIONS: The prevalence of HSPM was 6.6%. Over one-third of affected second primary molars were associated with demarcated lesions in the first permanent molars. The chance of severe caries increased with the increase in the demarcated lesion severity.

Clinical color intensity of white spot lesions might be a better predictor of enamel demineralization depth than traditional clinical grading.

INTRODUCTION: The aims of this study were to calculate the volume of white spot lesions by using microcomputed tomography and to determine which clinical attribute of the white spot lesion could better predict its volume: the clinically visible white spot lesion surface area or its color intensity. METHODS: White spot lesions were induced in 8 patients in vivo on 23 healthy premolars destined for extraction during orthodontic treatment by using specially designed plaque-retaining orthodontic bands. After 7 weeks, the premolars were extracted. After extraction, the resulting white spot lesions were photographed and clinically graded. The teeth were analyzed with microcomputed tomography. RESULTS: After 7 weeks, 70% of the teeth developed clinical white spot lesions. Clinically, the size of the lesions varied from minor to severe. Their volumes varied from 0 to 1.2931 mm(3). The traditional grades for white spot lesions correlated significantly with color intensity. A significant correlation was found between white spot lesion color intensity and lesion volume. This correlation was found to be better than that between the white spot lesion clinical score and lesion volume. CONCLUSIONS: Our results indicate that white spot lesion color intensity might predict the depth of enamel demineralization as well as or better than traditional white spot lesion scoring. Therefore, the dentist could use this information when planning treatment for white spot lesions.

Effect of low pH on surface rehardening efficacy of high concentration fluoride treatments on non-cavitated lesions.

OBJECTIVE: Professionally applied acidulated phosphate fluoride has been shown to reduce caries incidence. However, it has been suggested that its efficacy might be reduced in advanced non-cavitated lesions. This study aimed to compare the surface rehardening and fluoride uptake effect of 2%-NaF solutions at different pH on non-cavitated caries-like lesions with two different levels of demineralization. METHODS: Human enamel specimens were demineralized to create early and advanced non-cavitated lesions. Specimens for each type of lesion were divided into 3 groups, treated for four minutes with either 2%-NaF pH 3.5, 2%-NaF at pH 7.0, or neutral deionized water, and exposed to a pH cycling remineralization/demineralization model for five days. An additional treatment was then done as described above followed by five more days of cycling (total of 2 treatments, ten-day pH cycling). Specimens were analyzed for surface microhardness change and fluoride uptake. RESULTS: It was found that for both types of lesions, acidic pH fluoride treatment was significantly (p<0.05) more effective than neutral pH treatment in rehardening the lesion surface and promoting fluoride uptake. Furthermore, the low pH vs neutral pH difference in rehardening was significantly larger in the less demineralized lesions (p=0.0001). Water treatment resulted in no rehardening or fluoride uptake. CONCLUSIONS: Results from this study suggest that high concentration fluoride treatments at acidic pH are more effective in rehardening the surface of non-cavitated caries lesions and promoting fluoride uptake than those at neutral pH. This effect appears to be greater in less demineralized lesions when compared to more advanced ones. CLINICAL SIGNIFICANCE: The results of this investigation suggest that when no other attenuating circumstances are present (e.g., the possibility of damaging tooth-coloured restorations), high concentration fluoride treatments for high risk individuals might be more efficacious using products at low pH.

Twenty-four month clinical evaluation of fissure sealants on partially erupted permanent first molars: glass ionomer versus resin-based sealant.

BACKGROUND: Glass ionomer sealants are an alternative to resin-based sealants, especially for use in partially erupted permanent molars. The authors conducted a study to compare the retention, marginal staining and cariostatic properties of a glass ionomer sealant with those of a resin-based sealant during a 24-month period. METHODS: We included in this study 39 patients aged 5 through 9 years who had bilateral partially erupted first permanent molars. One of us (S.B.) placed a resin-based sealant (Delton Plus FS+, Dentsply Professional, York, Pa.) (group D) on a partially erupted first molar in one quadrant of the maxilla or mandible and a glass ionomer sealant (GC Fuji Triage White, GC America, Alsip, Ill.) (group T) in the other quadrant. Two masked and calibrated investigators (S.A.A., J.C.) evaluated the sealants for retention, marginal staining and carious lesions at three, six, 12 and 24 months. The authors used a multinomial regression for statistical analysis (P < .05). RESULTS: The recall rate was 69.2 percent at 24 months. Two sealants from group D and three from group T were lost completely. Complete retention rates at 24 months were 40.7 and 44.4 percent for groups D and T, respectively. The authors found no statistically significant difference in retention rates between groups at each recall examination (P > .05). For marginal staining, sealants in the resin-based group exhibited statistically higher marginal staining than did sealants in the glass ionomer group (P < .05). Although the authors detected no caries in teeth in group T, teeth in group D in which the sealant was lost completely experienced demineralization. CONCLUSIONS: Resin-based and glass ionomer sealants exhibited similar retention rates at 24 months. However, marginal staining was lower in the glass ionomer group, and the authors found no caries in teeth in this group. Consequently, glass ionomer sealants may be a better choice when salivary contamination is expected. CLINICAL IMPLICATIONS: Sealing during tooth eruption presents a particular challenge owing to difficulty in isolating the tooth. Glass ionomers may be a better material for sealing partially erupted molars.

MI Paste Plus to prevent demineralization in orthodontic patients: a prospective randomized controlled trial.

INTRODUCTION: Enamel demineralization is a problem in orthodontics. Fluoride is partially effective in addressing this problem, but additional treatment options are needed. The objective of this prospective randomized controlled trial was to determine the effectiveness of a new product, MI Paste Plus (GC America, Alsip, Ill), in the prevention or reduction of white spot lesions in orthodontic patients. METHODS: Sixty patients who were undergoing routine orthodontic treatment were recruited for this prospective randomized clinical trial. A double-blind method of randomization was used to determine whether each patient received the MI Paste Plus or a placebo paste (Tom's of Maine, Salisbury, United Kingdom). Each patient was asked to administer the paste by using a fluoride tray for a minimum of 3 to 5 minutes each day at night after brushing. Photographic records obtained in a light-controlled environment were used to record the presence or absence of white spot lesions in both groups. The enamel decalcification index was used to determine the number of white spot lesions per surface at each time interval. Patients were followed at 4-week intervals for 3 months. A scoring system from 0 to 6 was used to determine the level of caries or cavitations. This system was also used for each tooth at each time interval. RESULTS: Fifty patients (26 using MI Paste Plus, 24 using the placebo paste) completed the study. The enamel decalcification index scores for all surfaces were 271 and 135 at the start of treatment and 126 and 258 at the end of treatment for the MI Paste Plus and placebo paste groups, respectively. The enamel decalcification index scores in the MI Paste Plus group reduced by 53.5%, whereas the placebo group increased by 91.1% during the study period. A 3-way analysis of variance (ANOVA) was done for the average enamel decalcification index scores. The surface type, the product/time interactions, and the product/surface interactions of the mean enamel decalcification index scores were significant (P <0.05). CONCLUSIONS: MI Paste Plus helped prevent the development of new white spot lesions during orthodontic treatment and decreased the number of white spot lesions already present. The placebo paste had no preventive action on white spot development during orthodontic treatment; the number of lesions actually increased. MI Paste Plus reduced white spots on the gingival surfaces; the placebo paste had the opposite effect. The incisal surface effect on the mean enamel decalcification index scores over time and between products was highly significant. The incisal enamel decalcification index scores were consistently higher than those for the other surfaces (mesial, distal, and gingival).

Banding versus bonding of first permanent molars: a multi-centre randomized controlled trial.

OBJECTIVE: To assess the effectiveness of banding versus bonding of first permanent molars during fixed appliance treatment; in terms of attachment failure, patient discomfort and post-treatment enamel demineralization. DESIGN: Multi-centre randomized clinical trial. SETTING: One District General Hospital Orthodontic Department and two Specialist Orthodontic Practices. PARTICIPANTS: Orthodontic patients aged between 10 and 18 years old, randomly allocated to either receive molar bands (n=40) or molar bonds (n=40). METHOD: Bands were cemented with a conventional glass ionomer cement and tubes were bonded with light-cured composite to all four first permanent molar teeth for each subject. Attachments were reviewed at each recall appointment to assess loosening or loss. The clinical end point of the trial was the day of appliance debond. Enamel demineralization at debond was assessed using the modified International Caries Assessment and Detection System (ICDAS). RESULTS: The first time failure rate for molar bonds was 18·4% and 2·6% for molar bands (P=0·0002). Survival analysis demonstrated molar bonds were more likely to fail compared with molar bands. First permanent molars with bonded tubes experienced more demineralization than those with cemented bands (P=0·027). There was no statistically significant difference in discomfort experienced by patients after banding or bonding first permanent molars (P>0·05). CONCLUSION: This study shows that as part of fixed appliance therapy, American Orthodontics photoetched first permanent molar bands cemented with 3M ESPE Ketac-Cem perform better than American Orthodontics low profile photo-etched and mesh-based first permanent molar tubes bonded with 3M Unitek Transbond XT in terms of failure behaviour and molar enamel demineralization.

Exposure to lead exacerbates dental fluorosis.

AIM: Our aim was to test the hypothesis that co-exposure to lead and fluoride alter the severity of enamel fluorosis. MATERIALS AND METHODS: Wistar rats were allocated in four groups: control, and 3 groups that received water containing 100 ppm of fluoride (F), 30 ppm of lead (Pb), or 100 ppm of F and 30 ppm of Pb (F+Pb) from the beginning of gestation. Enamel analysis and F and Pb determinations in enamel, dentine, and bone were performed in 81-day-old animals. Fluorosis was quantified using a new fluorosis index based on the identification of incisor enamel defects (white bands and white islets, representing hypomineralization, and cavities) weighted according to their severity and quantity. Hypomineralization was validated histopathologically by polarizing microscopy and microradiography. Scores were given by two blinded calibrated examiners (intra and interexaminer kappa values were 0.8 and 0.86, respectively). RESULTS: The control and the Pb groups presented normal enamel. The F+Pb group presented more severe enamel defects compared with the F group (P<0.0001). CONCLUSIONS: This study shows that lead exacerbates dental fluorosis in rodents, suggesting that co-exposure to lead may affect the degree of fluorosis.

Prevalencia de hipomineralización inciso-molar en niños nacidos en diferentes lugares de la República Argentina / Prevalence of molar incisor hypomineralization in children born in different places of the Argentine Republic

En el año 2003 fue aceptada la terminología hipomineralización inciso-molar (HIM) por la Academia Europea de Odontopediatría, para definir esta patología de etiología aún desconocida que afecta a los primeros molares permanentes y en ocasiones a los incisivos. El objetivo del presente trabajo fue estimar la prevalencia de HIM en niños de diferentes regiones de la República Argentina, asociando posibles factores ante su aparición. Materiales y métodos: fueron examinados 411 niños de ambos secos con edades entre 7 y 13 años (media= 9.66 +-1.5) en centros odontológicos de diferentes localidades argentinas. Se registraron datos relacionados con su aparición, gravedad y severidad. Se analizó estadísticamente asociación y correlación. Resultados: la prevalencia de HIM fue 25,1 por ciento en molares y 18,7 por ciento en molares e incisivos. Se encontró asociación significativa entre antibiótico administrados durante el embarazo e HIM y entre otitis padeciad por los niños e HIM. Conclusión: el alto porcentaje hallado en este trabajo determina que la HIM es una patología que se encuentra presente en nuestro país.

Cariogenicity and acidogenicity of human milk, plain and sweetened bovine milk: an in vitro study.

UNLABELLED: The objective of the present study was to determine the acidogenicity and cariogenicity of human breast milk and plain and sweetened packaged bovine milk. STUDY DESIGN: First all milk specimens were inoculated with a cariogenic strain of Streptococcus mutans (SM). The culture pH and number of colony forming units (cfus) was assessed. Second, the buffer capacity of all milk specimens was evaluated by mixing with acid. Finally, enamel windows were created on extracted primary maxillary incisors and colonized with SM. Enamel demineralization and caries progression were assessed visually, histologically, and radiographically at the end of twelve weeks. RESULTS: Plain and sweetened packaged bovine milk (BM) supported greater bacterial growth and caused more fermentation than human breast milk (HBM). The buffer capacity values for plain and sweetened bovine milk were highest; HBM, however had poor buffering capacity. The progression of the carious lesions into the dentin was most severe for the sweetened bovine milk. CONCLUSIONS: HBM and plain bovine milk are relatively cariogenic in an in vitro caries model in the absence of saliva. However, supplementation with sugar exponentially enhances the cariogenic potential of the natural milk.

Molar-incisor-hypomineralisation (MIH). Retrospective clinical study in Greek children. I. Prevalence and defect characteristics.

AIM: This was to evaluate the prevalence and the clinical characteristics of MIH in a group of Greek children. METHODS: During the years 2003--2005, all MIH cases diagnosed according to the recently set criteria were selected from the new patients clinic of a Community Dental Centre for Children (Athens). Age, gender and teeth involved were recorded. The severity of MIH was determined collectively by dividing the affected teeth in two groups; a) mild defect (demarcated opacities) and b) moderate/severe defect (enamel breakdown and atypical restorations). Evaluation of the distribution of the affected teeth within MIH cases was performed in a separate group of 225 affected children aged 8-12 years with their entire 12 'index' teeth erupted. RESULTS: From the 3,518, 5.5 to 12 year old children that were examined, there were 360 (10.2%) children with MIH, 211 (58.6%) females and 149 (41.4%) males, with 1,926 affected teeth, 1,231 molars and 695 incisors. In the molars group, maxillary molars were more frequently affected (87.8/90.3%) than mandibular (81.7/82.2%). In the central incisor group, maxillary teeth were also more frequently affected (50/55%) than mandibular (24.4/25%), while laterals were the least affected. In all there were 37.9% molars with moderate/severe defects as compared with 4.9% incisors, the remaining 62.1% and 95.1% respectively being mild. The various associations between the affected teeth were evaluated in the sub-group of 225 MIH children with all 'index' teeth erupted (1,286 affected teeth, 776 molars and 510 incisors), with mean number of affected teeth per child being 5.7; separately for molars 3.4 and for incisors 2.2. In these cases 28.4% of the children had only molars affected and 71.6% had both molars and incisors. In descending order the associations of affected teeth more frequently found were: 4 molars/2 incisors (23.5%), 4 molars/4 incisors (16.8%), 4 molars alone (15.1%) and 2 molars alone (9.7%), the remaining being much less. STATISTICAL ANALYSIS: As age increased the clinical severity of the affected teeth became more prevalent (p=0.0001), and when the total number of affected teeth was assessed the likelihood of having severe defect was also increased (p=0.001). CONCLUSION: The prevalence of the defect in the present study was 10.2% with maxillary teeth being more frequently affected. Severity increased with age. Mild defects were much more frequent, particularly in incisors. The total number of teeth affected and the most frequently found associations were, 4 molars/2 incisors, 4 molars/4 incisors, 4 molars alone and 2 molars alone.

Clinical studies on molar-incisor-hypomineralisation part 2: development of a severity index.

AIM: This was to examine the records of 182 children (aged 6-14 years) with molar-incisor-hypomineralisation (MIH) or molar hypomineralisation (MH) in order to develop and examine a Hypomineralisation Severity Index for first permanent molars (FPMs). STUDY DESIGN: Records of 429 FPMs in these children were examined and scored for eruption status, extent of hypomineralisation, sensitivity, number of restorative treatments; summed scores were converted to an index for each dentition (possible range: 1.25-7.00). Indices were examined regarding medical conditions occurring singly or in combinations in parentally-recalled children's histories to age 3 years; mean indices were compared for dentitions with these conditions/combinations. RESULTS: The proportion of FPMs receiving no/preventive treatment was higher in dentitions with MH than with MIH (56% vs. 41%); restorative treatment for FPMs was more frequent in dentitions with MIH than with MH (45% vs. 29%). Dentitions with MIH had higher severity indices than those with MH (MIH: index range: 3.25-5.25: 43%; MIH: index range: 1.25-2.00: 61%). Mean severity indices clearly had a higher trend in dentitions of children with certain condition combinations than for those without. Ten condition combinations each contained 3 to 5 medical conditions; 11/12 condition combinations included fevers; 9/12 included chicken pox; 9/12 included perinatal conditions, 6/12 included antibiotic use. CONCLUSIONS: A preliminary Hypomineralisation Severity Index developed for dentitions with hypomineralised first permanent molars in children has shown that MIH and MH form part of an MIH spectrum, where MIH is a more severe form of the condition than MH. The index has indicated associations between hypomineralisation of these molars and combinations of medical conditions, particularly implicating fevers, chicken pox, perinatal conditions and antibiotic use. Further clinical studies are indicated to validate the proposed index and confirm its prognostic value in treatment planning.

Early enamel lesion part I. Classification and detection.

There has been a paradigm shift from Black's 'extension for prevention' to a minimal intervention approach in the recent time. The most important aspect in diagnosis of earliest stages of enamel demineralization involves accurate and reliable detection of such lesions. The newer diagnostic aids would enable the dentist to detect and diagnose early enamel lesions and direct appropriate preventive measures to promote remineralization and conservation of the tooth substance. A high level of caries experience necessitates preventive strategies which are more cost effective than surgical intervention and restorative procedures.

Molar incisor hypomineralization: review and prevalence data from the study of primary school children in Kaunas/Lithuania.

AIMS: These were to determine the prevalence of MIH in a group of primary school children in Kaunas, Lithuania and to compare the prevalence of MIH in Lithuania with the prevalence in other countries using published data. METHODS: First permanent molars and all permanent incisors were examined in 1277 children, aged 7 to 9 years and having at least one erupted permanent molar, for demarcated opacities, post-eruptive enamel breakdown, atypical restorations and extractions due to MIH, according to the criteria, provided by the EAPD experts. Examinations were performed by two calibrated observers (k=0.829). RESULTS: Of all the children 190 (14.9%) had hypomineralization defects in at least one index tooth, 124 (9.7%) had at least one affected molar and were considered as having MIH. Only demarcated opacities were present in 68 (54.8%) of children with MIH, 35 (28.2 %) had at least one tooth with breakdown, 21 (16.9%) had atypical restorations. No teeth had been extracted due to MIH. Children with 3-6 affected teeth were 3.5 times more likely to have enamel breakdown and/or atypical restorations when compared with the children having only one or two affected teeth. Of the 124 children with MIH 96 (77.4%) had lesions only in molars, 28 (22.6%) had both - molars and incisors - affected. CONCLUSIONS: MIH was common among 7-9 years old Lithuanian children; majority of the affected children were affected mildly. Severity of the lesions was increasing with the number of affected teeth. Compared to the other studies MIH in Lithuania was moderately prevalent.

The International Caries Detection and Assessment System (ICDAS): an integrated system for measuring dental caries.

This paper describes early findings of evaluations of the International Caries Detection and Assessment System (ICDAS) conducted by the Detroit Center for Research on Oral Health Disparities (DCR-OHD). The lack of consistency among the contemporary criteria systems limits the comparability of outcomes measured in epidemiological and clinical studies. The ICDAS criteria were developed by an international team of caries researchers to integrate several new criteria systems into one standard system for caries detection and assessment. Using ICDAS in the DCR-OHD cohort study, dental examiners first determined whether a clean and dry tooth surface is sound, sealed, restored, crowned, or missing. Afterwards, the examiners classified the carious status of each tooth surface using a seven-point ordinal scale ranging from sound to extensive cavitation. Histological examination of extracted teeth found increased likelihood of carious demineralization in dentin as the ICDAS codes increased in severity. The criteria were also found to have discriminatory validity in analyses of social, behavioral and dietary factors associated with dental caries. The reliability of six examiners to classify tooth surfaces by their ICDAS carious status ranged between good to excellent (kappa coefficients ranged between 0.59 and 0.82). While further work is still needed to define caries activity, validate the criteria and their reliability in assessing dental caries on smooth surfaces, and develop a classification system for assessing preventive and restorative treatment needs, this early evaluation of the ICDAS platform has found that the system is practical; has content validity, correlational validity with histological examination of pits and fissures in extracted teeth; and discriminatory validity.