Comparisons of Precision of Fit Between Cast and Computer Numeric Controlled Milled Titanium Implant Frameworks for the Edentulous Mandible

INTRODUCTION: Titanium frameworks have for the last decade been discussed as an option to conventional gold alloy castings in implant dentistry. So far no reports have been made to show milled titanium frameworks and their difference in precision compared to conventional castings, and how laboratory handling andfusing of veneers to the titanium frames affect the precision of fit. PURPOSE: To investigate and compare the precision of fabrication in repeatedly produced Computer Numeric Controlled milled frameworks with conventional castings, and to analyze the distortion from application of different veneering materials (porcelain and acrylic resin veneers). MATERIAL AND METHODS: Twenty identical titanium frameworks were fabricated by means of a Computer Numeric Controlled milling technique for one and the same master model. Five conventional frameworks were cast as a control group to the same model. The frames were measured with regard to fit in a coordinate measuring machine linked to a computer. Measurements were made during different stages of handling of the titanium framework, and after veneering materials had been applied. RESULTS: The Computer Numeric Controlled frameworks showed a statistically (p0.05) affect the fit of the titanium frameworks. CONCLUSION: It is possible to fabricate implant supported titanium frameworks by means of the present Computer Numeric Controlled technique with very high precision and repeatability

Comparisons of Precision of Fit Between Cast and Computer Numeric Controlled Milled Titanium Implant Frameworks for the Edentulous Mandible

INTRODUCTION: Titanium frameworks have for the last decade been discussed as an option to conventional gold alloy castings in implant dentistry. So far no reports have been made to show milled titanium frameworks and their difference in precision compared to conventional castings, and how laboratory handling andfusing of veneers to the titanium frames affect the precision of fit. PURPOSE: To investigate and compare the precision of fabrication in repeatedly produced Computer Numeric Controlled milled frameworks with conventional castings, and to analyze the distortion from application of different veneering materials (porcelain and acrylic resin veneers). MATERIAL AND METHODS: Twenty identical titanium frameworks were fabricated by means of a Computer Numeric Controlled milling technique for one and the same master model. Five conventional frameworks were cast as a control group to the same model. The frames were measured with regard to fit in a coordinate measuring machine linked to a computer. Measurements were made during different stages of handling of the titanium framework, and after veneering materials had been applied. RESULTS: The Computer Numeric Controlled frameworks showed a statistically (p0.05) affect the fit of the titanium frameworks. CONCLUSION: It is possible to fabricate implant supported titanium frameworks by means of the present Computer Numeric Controlled technique with very high precision and repeatability

Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Cooccurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9-86.6) and the negative predictive value 84.7% (80.6-88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9-17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47-0.68). The odds ratio was 18.2 (9.39-35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH

The effect of premature extraction of primary teeth on the subsequent need for orthodontic treatment.

AIM: To investigate if premature extraction of primary teeth was associated with orthodontic need in the permanent dentition. STUDY DESIGN: This was a case-control study based on retrospective dental records. METHODS: As part of NHS (UK) Dental Epidemiology Programme a sample of 366, 12-year-old children from Bradford and Airedale were examined. The survey collected data on patient demographics, dental health status including orthodontic need. Data linkage was undertaken for those children participating in the NHS Dental Epidemiology Programme who had previously accessed the local Salaried Dental Service (SDS). For these children, retrospective dental information was collected about premature extraction of primary teeth. RESULTS: From the 366 children who were surveyed, 116 children had received treatment at the local SDS in the past. Significantly more children from ethnic minorities, low socioeconomic backgrounds and high caries rate (p < 0.001) were seen in the SDS. For the 107 children who attended SDS, an increased total number of primary teeth extractions was positively associated with orthodontic need (odds ratio:1.18, CI -1.01 to 1.37). STATISCTICS: Multilevel modelling was undertaken to identify variables associated with orthodontic need. CONCLUSIONS: In the study group, orthodontic need was significantly associated with the number of primary teeth extracted

Mutations in CNNM4 Cause Jalili Syndrome, Consisting of Autosomal-Recessive Cone-Rod Dystrophy and Amelogenesis Imperfecta

The combination of recessively inherited cone-rod dystrophy (CRD) and amelogenesis imperfecta (AI) was first reported by Jalili and Smith in 1988 in a family subsequently linked to a locus on chromosome 2q11, and it has since been reported in a second small family. We have identified five further ethnically diverse families cosegregating CRD and AI. Phenotypic characterization of teeth and visual function in the published and new families reveals a consistent syndrome in all seven families, and all link or are consistent with linkage to 2q11, confirming the existence of a genetically homogenous condition that we now propose to call Jalili syndrome. Using a positional-candidate approach, we have identified mutations in the CNNM4 gene, encoding a putative metal transporter, accounting for the condition in all seven families. Nine mutations are described in all, three missense, three terminations, two large deletions, and a single base insertion. We confirmed expression of Cnnm4 in the neural retina and in ameloblasts in the developing tooth, suggesting a hitherto unknown connection between tooth biomineralization and retinal function. The identification of CNNM4 as the causative gene for Jalili syndrome, characterized by syndromic CRD with AI, has the potential to provide new insights into the roles of metal transport in visual function and biomineralization