Follow-up of first permanent molar restorative treatment with and without Molar Hypomineralization

Hypomineralization (MH) are controversial. The aim of this study was to compare need for treatment and status of restorations performed on first permanent molars in patients with and without MH. Retrospective design based on the clinical records of 153 patients who had received comprehensive care in 2014 at the Clinic of the Children's Comprehensive Dentistry Department (FOUBA) by 3 pediatric dentists (Kappa MH 0.94), and who attended periodical follow-up visits for at least 24 months. Need for treatment in first molars, and type and longevity of treatment were recorded (modified Ryge criteria /USPHS, Kappa 0.78). Results were compared between patients with MH and without MH. The Kruskal Wallis test was used to compare follow-up time, the asymptotic test was performed to compare proportions, and relative risk (RR) was calculated to compare need for treatment. Mean follow-up times for the 595 teeth analyzed were 61.7±20.1 months for Group without MH, and 57.5±23.9 months for Group with MH (p=0.0504). The percentages of teeth requiring at least one treatment were 7.2% in Group without MH and 27.5% in Group with MH (RR = 3.80, p <0.001). Of the teeth treated in Group with MH 23.1% required retreatment, while none of the teeth in Group without MH did. The need for treatment was approximately 4 times higher in molars affected with MH, with greater probability of retreatment.

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.

Comparison of Mineral Density in Molar Incisor Hypomineralization applying fluoride varnishes and casein phosphopeptide-amorphous calcium phosphate

The aim of the present work was to evaluate and compare variations in mineral density (MD) using laser-induced fluorescence (LF) after applying 5% Sodium Fluoride Varnish (Duraphat®), 5% Sodium Fluoride Varnish with Tricalcium Phosphate (Clinpro®) or Casein phosphopeptide-amorphous calcium phosphate (Recaldent®) on teeth with Molar Incisor Hypomineralization (MIH). Mineral density of 92 MIH teeth with mild (Mi) and moderate (Mo) lesions was assessed using a DIAGNOdent device (KaVo, Biberach, Germany). LF values were recorded on day 0 (baseline) and on days 15, 30 and 45; the remineralizing agents were applied immediately after LF readings at baseline and on days 15 and 30. Data corresponding to Mi and Mo lesions were analyzed separately. Significant differences were observed both in mild (p<0.01) and moderate (p<0.000005) lesions. Differences between Recaldent® and Clinpro®, and between Duraphat® and Clinpro® (global level 0.10) were found in Mi lesions. All 3 pairs ofproducts differed significantly in Mo lesions (global level 0.05). The results obtained under the conditions used here allow concluding that Clinpro® was more effective in mild lesions whereas Duraphat® was more effective in moderate lesions.

Ultrastructure of the surface of dental enamel with molar incisor hypomineralization (MIH) with and without acid etching

The aim of the present work was to analyze the ultrastructure and mineral composition of the surface of the enamel on a molar with MIH, with and without acid etching. A permanent tooth without clinical MIH lesions (control) and a tooth with clinical diagnosis of mild and moderate MIH, with indication for extraction, were processed with and without acid etching (H3PO4 37%, 20") for observation with scanning electron microscope (SEM) ZEISS (Supra 40) and mineral composition analysis with an EDS detector (Oxford Instruments). The control enamel showed normal prismatic surface and etching pattern. The clinically healthy enamel on the tooth with MIH revealed partial loss of prismatic pattern. The mild lesion was porous with occasional cracks. The moderate lesion was more porous, with larger cracks and many scales. The mineral composition of the affected surfaces had lower Ca and P content and higher O and C. On the tooth with MIH, even on normal looking enamel, the demineralization does not correspond to an etching pattern, and exhibits exposure of crystals with rods with rounded ends and less demineralization in the inter-prismatic spaces. Acid etching increased the presence of cracks and deep pores in the adamantine structure of the enamel with lesion. In moderate lesions, the mineral composition had higher content of Ca, P and Cl. Enamel with MIH, even on clinically intact adamantine surfaces, shows severe alterations in the ultrastructure and changes in ionic composition, which affect the acid etching pattern and may interfere with adhesion.

Assessment of Mandibular Movements in 10 to 15 Year-old Patients With and Without Temporomandibular Disorders

The aim of this study was to establish reference values for mandibular movements in 10- to 15-year-olds without dysfunction and compare these values to those in patients of the same age with tempromandibular disorders (TMD) and those found previously in a group of children younger than 11 years old without TMD. Children of both genders who visited the Department of Comprehensive Pediatric Dentistry at Buenos Aires University in 2013 and whose parents or guardians provided consent were evaluated using TMD/RDC by standardized pediatric dentists (Kappa 0.88). Three groups were formed according to diagnostic summary: Group C, without TMD; Group Ia, with myofascial pain, and Group Ib, pain with limited mouth opening. The following variables were analyzed: age, gender and mandibular movements. The sample included 169 patients aged 12.5±1.76 years, of whom 62.36% did not have TMD (C) while 37.27% were diagnosed with muscle disorder (29.58% Ia and 7.69% Ib). For Group C, the following values (in mm) were recorded: maximal unassisted opening: 48.28±6.14; right lateral movement 8.78±2.50; left lateral movement: 9.60±2.64; protrusion: 4.94±2.58 and overbite: 2.98 ± 2.5, with no variation associated to sex, but with differences in the values recorded for all movements compared to those obtained for mixed dentition (p=0.0001). Analysis of mean values for mandibular movements in all 3 groups only revealed differences for maximal unassisted opening (p= 0.0317). With relation to gender, TMD was more frequent in females, with significant differences between Groups C and Ia (p=0.019). In males without dysfunction, average maximal opening was 48.28±6.14mm, with lower values in patients with TMD. Mandibular movements in pediatric patients without TMD showed significant differences according to dentition type and age.

[Comparison of the prevalence of molar incisor hypomineralization among children with different health care coverage in the cities of Buenos Aires (Argentina) and Montevideo (Uruguay)]

The aim of this study was to compare the prevalence of molar incisor hypomineralization (MIH) among children with different health care coverage in Buenos Aires and Montevideo. An observational, cross-sectional and descriptive study was designed, considering children born from 1993-2003 who were seen in the Chairs of Comprehensive Children's Dentistry (Universidad de Buenos Aires) and of Pediatric Dentistry (Universidad de la República) and at five private dental offices between April and December 2010. Two groups were defined: A (Buenos Aires; n=1,090) and B (Montevideo; n=626). The clinical diagnosis was carried out with calibrated examiners (Kappa: 0.94) using the Mathu-Muju and Wright criteria. The prevalence of MIH was found to be 16.1% in A and 12.3% in B (p=0.03), with statistically significant differences between the public and private care sectors in both groups (A p=0.0008; B p=0.0004) and a positive correlation between MIH and year of birth (A p=0.001; B p=0.005). The results show that MIH is an emerging pathology and that MIH prevalence is related to year of birth and access to health care.

Prevalence of molar-incisor hypomineralization (MIH) in children seeking dental care at the Schools of Dentistry of the University of Buenos Aires (Argentina) and University of la Republica (Uruguay)

The objectives of this study are to compare the prevalence of MIH in children seeking dental care spontaneously at the Department of Comprehensive Children's Dentistry of the University of Buenos Aires (UBA) and Department of Pediatric Dentistry of the University of La República (UdelaR) and to analyze the distribution according to year of birth, sex, age, number of affected teeth and maximum degree of severity in molars and incisors. During 2010, nine pediatric dentists from both schools (Kappa = 0.94) assessed all children born between 1993 and 2003 whose 4 first molars and 8 permanent incisors had erupted. Specially designed charts were used to record sex, year of birth, institution, presence of MIH, number of affected incisors and molars and maximum degree of severity for each tooth. Two groups were formed: UBA: A (n = 512) and UdelaR: B (n = 463).

RESULTS

975 children (11.6 +/- 2.67 years) were evaluated. The prevalence of MIH in the total sample was 6.56%, without significant differences between A and B (p = 0.76). There was no significant difference between groups regarding age (p = 0. 95) or sex (p = 0.30). A significant increase was found in both institutions according to year of birth during the study period. (A: p = 0.0017) B: p = 0. 0058).

CONCLUSIONS

The results of this study show a similar prevalence of MIH among patients seeking dental care at the Schools of Dentistry of the University of Buenos Aires (Argentina) and University of la República (Uruguay). No significant difference was found comparing the distribution by sex, affected teeth or severity of each tooth. A highly significant positive correlation was found regarding the year of birth. The relevance of MIH as an emerging pathology requires studies on larger samples covering the entire countries.

Prevalence of molar incisor hypomineralization in the city of Buenos Aires

The prevalence of Molar Incisor Hypomineralization (MIH) still remains unknown in Argentina. The objectives of this work were to: estimate prevalence of MIH in a group of children seeking dental care in the city of Buenos Aires, analyze distribution according to year of birth and compare prevalence and severity of MIH in children with different access to health care services. A prospective, observational, transversal, descriptive study was designed, to be conducted on children seeking attention at Department of Comprehensive Children's Dentistry at the School of Dentistry of Buenos Aires University and at 3 pediatric dentistry offices attended by members of the team, located in Buenos Aires city (Kappa 0.933 0.911-0.952), from April to August 2010. The study included all children born between 1993 and 2003, whose 4 first molars and 8 permanent incisors had erupted. After prophylaxis and drying, the teeth were clinically evaluated and specially designed charts were used to record sex, year of birth, type of access to dental care, presence of MIH, number of affected incisors and molars, and maximum degree of severity for each tooth. The data obtained were analyzed using percentages, Fisher's Exact Test and Linear regression. 1098 children, mean age 11.3 years (11.08-11.39) were evaluated. Prevalence of MIH in this study was 15.9% (13.8-18.2). A highly significant positive correlation was obtained between MIH and year of birth (p<0.0001). Group A (private sector: prepaid medical insurance) was made up of 586 children (age: 10.92 6.22-15.62) while group B (public sector: university hospital) was made up of 512 children (age: 11.59 5.31-16.90). In Group A, MIH prevalence was 24.40% (20.9-27.9) while in Group B it was 6.44% (4.31-8.56) (p<0.0001). Of the affected molars, 37% (32.2-42) in A and 13.7% (6.7-23.8) in B had grade 3 lesions, with loss of enamel (p<0.0001). In this study, MIH was a frequent pathology (15.9%) and a significant increase was found according to year of birth during the study period. Patients with better access to health care had greater prevalence and degree of severity of MIH.

[Relationship between dysfunctions and parafunctional oral habits, and temporomandibular disorders in children and teenagers]

Oral parafunctional habits and orofacial myofunctional dysfunctions are commonly observed in children and considered as contributory factors for temporomandibular disorders (TMD). The aim of this work was to describe the frequency of oral parafunctional habits and orofacial myofunctional dysfunctions and to evaluate the association between them and signs and symptoms of TMD in patients attending to the TMD section of the Pediatric Dentistry Department of the University of Buenos Aires.

METHODS

Data obtained from dental records performed during 2003-2007 were entered into a database registering age, gender, reason for consultation, psychological stress, signs, symptoms, diagnosis, dysfunctions and parafunctions, for statistical analysis.

RESULTS

The sample was constituted by 133 patients (average age: 12 +/- 3 years old). Ninety six percent of patients showed dysfunctions and/or parafunctions. Regarding dysfunctions, they were present in 78% of the sample; 48% had dysfunctional swallowing; 45% oral and mixed breathing, and 29% chewing food on one preferred side. With regard to parafunctions, bruxism was present in 74% of cases, gum chewing habit in 55%, nail biting in 48%, biting in 28%, jaw play in 22%, and sucking in 14%. TMD symptoms were associated with total dysfunctions and parafunctions (p <0.05). Using multivariate analysis, results showed a significant correlation between masticatory dysfunction and clicking joint noise (p= 0.023) and bruxism as reason for consultation (p= 0.018).

CONCLUSIONS

Dysfunctions and parafunctions showed in this study a high prevalence and were significantly associated with TMD symptoms.

A model for the organization of a regional bank for musculoskeletal tissues in Italy

The national and local need for human tissues to be used in transplants is a high one, and constantly growing. Human, scientific and financial resources involved in guaranteeing safe and high-quality tissues as defined by the national guidelines for musculoskeletal tissue banks are considerable. For this reason we need to find adequate solutions to the problem of guaranteeing sufficient availability of tissues with the lowest cost possible for supply. The Piedmont Region Musculoskeletal Tissue Bank, which is located in an Azienda Ospedaliera, has been organized to guarantee the quality of its tissues via biological validation and scientific-clinical coordination; it makes use of the collaboration of removal centers that send tissues taken from the central bank for certification and identifies several centers for preservation; it collaborates with a bank of national importance for tissue processing. The publication of regulations and tariffs based on cost analysis improves the procedures.

[Antipyrine clearance in liver resections]

We studied antipyrine clearance (APC1) in 19 healthy controls, 10 cirrhotic patients, 20 patients undergoing partial hepatectomy for liver tumors (14 with cirrhosis and 6 without cirrhosis). The aim of the study was to evaluate if the test represents a measure of the residual hepatic function and a useful index of surgical risk in cirrhotic patients following partial hepatectomy. The APC1 was significantly reduced in cirrhotic patients ws healthy controls. It is reduced following partial hepatectomy in cirrhotic patients (p less than 0.001) and in non cirrhotic patients (n.s.). The APC1 was found to be related with the plasma level of albumin and pseudocholinesterase; it also was related with the Pugh's score for hepatic function. The APC1 is a satisfactory index of residual hepatic function. On the other hand it does not provide more useful information than the Pugh's score for surgical risk in liver resection.

Evaluation of the diagnostic value of serum bile acid in the detection and functional assessment of liver diseases

The diagnostic usefulness of fasting total serum bile acids (SBA/F) in the detection of liver diseases and assessment of different aspects of hepatic function alteration was evaluated in 61 healthy subjects and 186 patients with liver disease. The value of SBA/F was compared with other routine tests. In 49 healthy subjects and 92 patients, serum bile acids were also measured after the im administration of Ceruletide as a cholecystokinetic agent (SBA/C). The diagnostic efficacy for the detection of disease states was better with aspartate-aminotransferase (EC 2.6.1.1) and alanine-aminotransferase (EC 2.6.1.2) than with SBA/F. When SBA/C was also determined the diagnostic efficacy was not substantially better than the SBA/F test. In the assessment of hepatocellular necrosis SBA/F showed a higher rate of misclassification errors compared to alanine-aminotransferase (mean error 45% vs 17%), whereas SBA/F gave similar results with direct bilirubin and pseudocholinesterase (EC 3.1.1.8) in the evaluation of cholestasis (mean error 40% vs 41%) and impaired biosynthesis (mean error 39% vs 40%), respectively. Serum bile acid determination did not show any significant diagnostic advantage with respect to the other routine liver tests.

Bromsulphalein (BSP) kinetics in the rat: a new approach in evaluating experimental hepatotoxicity

An animal model for the identification and definition of toxic liver damage, based on the investigation of the BSP metabolism in the rat is proposed. Different hepatotoxins can induce specific functional alteration on the different steps of the BSP hepatobiliary transport, mainly the uptake by hepatocytes and the biliary excretion. Removal curves of BSP from the plasma compartment as well as the biliary secretion were evaluated in rats treated with either alpha-naphthylisothiocyanate (ANIT) for metabolic cholestasis, or with carbon tetrachloride (CCl4) for fatty infiltration and necrosis of the liver. The data were compared with those obtained with untreated rats and with animals submitted either to complete or incomplete mechanically induced cholestasis. Our results lead to the conclusion that a satisfactory discrimination among different types of liver damage may be obtained when only two plasma parameters of BSP metabolism are considered: the disappearance rate for the early 5 min (K), and 15-min plasma BSP retention (R15). The model is proposed as a suitable tool for the evaluation of experimental hepatotoxicity in living rats giving a characterisation of the functional alteration and a measure of liver impairment.