The use of three-dimensional (3D) models of the dentition obtained from cone beam computed tomography (CBCT) is becoming increasingly more popular in dentistry. A recent trend is to replace the traditional dental casts with digital CBCT models for diagnosis, treatment planning and simulation. The accuracy of these models was previously assessed through comparing linear physical and radiographical measurements. However, this assessment technique is both observer and landmark dependent. The accuracy of 3D CBCT teeth reconstructions is yet to be reliably measured. To assess the accuracy of 3D CBCT reconstructions of the teeth using a semi-automated and observer-independent method and to assess the influence of field of view (FoV) selection on reconstruction accuracy. Fully dentate upper and lower dry human jaws, placed in a plastic box and immersed in water, were scanned using CBCT with small, medium and large FoV. The teeth were then scanned separately using MicroCT. Cone beam computed tomography and MicroCT 3D teeth models were compared, and mean surface difference was calculated per tooth for each FoV. Mean and (maximum) differences between MicroCT and CBCT were 120 +/- 40 (max. 679) microm, 157 +/- 39 (max. 824) micro and 207 +/- 80 (max. 862) microm for the small, medium and large FoV, respectively. Cone beam computed tomography models were larger than MicroCT because of larger voxel size. Our results indicate that CBCT may provide accurate 3D reconstructions of the teeth that can be useful for some clinical applications.

Aims: To detect the levels of fluoride (F), zinc (Zn) and lead (Pb) in primary teeth and drinking water and their relation to dental caries experience in school children aged 6-12 years living in two distinct areas in Ninevah Governorate using two different sources of drinking water supply. Materials and Methods: The samples consisted of 120 freshly extracted highly mobile free of dental caries human primary mandibular teeth and ten wells water samples with ten tap water samples which had been chosen randomly. The samples were analyzed for F by fluoride sensitive electrode and for Zn and Pb by computerized atomic absorption spectrophotometer. Assessments and recording of caries experience were done by application of decayed, missing and filled surfaces (dmfs) index for primary dentition. Results: Statistical analysis of the results indicated that the mean F and Zn concentrations in the teeth were 244.35 + 167.49 ppm; 87.41+ 36.64 ppm respectively of the rural children were significantly higher than in the teeth of urban children (104.53 + 52.75 ppm; 65.19+ 28.79 ppm respectively). Meanwhile the concentration of Pb in the teeth of the urban children (1.62+0.41 ppm) was significantly higher than in the teeth of rural children (0.94+ 0.80 ppm)(p<0.001). Statistically significant higher F concentration in the wells water (3.39+ 0.25 ppm) than urban water supply (0.19+ 0.07 ppm) (p<0.001). Statistically significant higher Zn concentration in the urban water supply (0.1.34+ 0.31 ppm) than wells water (0.07+ 0.03 ppm) (p<0.001), but Pb concentration in wells water was not detected. Statistically significant higher caries experience was found in urban children than in rural (p<0.001). In the rural and urban areas, a negative correlation in the dmfs with F and Zn concentrations in teeth while a positive correlation with Pb was observed. Conclusions: A highly significant F and Zn concentrations in primary teeth were found in rural area than the urban and the opposite was true for Pb concentration. High significant F concentration was found in the wells water than urban water supply, and the opposite was true for Zn, but Pb concentration in wells water was not detected. High significant differences in dental caries indices were found in urban children than in rural children.

Aims:To evaluate the effect of two types of disinfectant solutions(2% alkaline glutaraldehyde, 1% sodium hypochlorite) in wettability of three types of elastomeric impression materials (light body) which are used in crown and bridge restorations at different times of immersion. Materials and methods: Three types of elastomeric impression materials (light body) were formed on a flat acrylic resin block and allowed to set(five specimens of each impression material was done for each immersion time(15,30 and 60 minutes)of each disinfectant solution in addition to control groups). The wettability is indicated by measuring the contact angle of aqueous solution of CaSO4 on surface of cured impression materials. Results: indicated no significant effect of immersion times on wettability of three types of impression materials. The hydrophilic type produce high wettability. Conclusions: The disinfectant solutions have different effects on each impression material. Sodium hypochlorite has the greatest beneficial effect on wettability.

The aim of this study is to determine the effectiveness of mandibular infiltration compared with the mandibular block in treating mandibular primary molars in children and to relate it to the type of treatment performed. Materials and Methods: The study design was case control study. The study sample consisted of 98 cooperative children of age 3-9 years old. Forty eight children were the study group (infiltration group). Equal number of children to the study group matched for age and gender were chosen (block group), they had the same criteria of the study group and required the same type of treatment. Dental procedure included amalgam restorations, foromcresol pulpotomies, and extractions. Evaluations of pain for each anesthesia technique and type of treatment were conducted using sounds; motor and ocular changes indicating pain. Evaluations were made upon probing, during tooth preparation, coronal pulp removal and extraction. Results: No statistically significant difference was found between the two anesthetic techniques of pain, when performing amalgam restorations (p>0.05). Mandibular infiltration was significantly less effective than mandibular block for pulpotomy and extraction (p<0.05). Conclusions: In this study, the mandibular infiltration was found to be a reliable local anesthetic technique in amalgam restoration. For pulpotomy and extraction, mandibular infiltration was not as effective as mandibular block. It is recommended to avoid the mandibular infiltration anesthesia, whenever possible for pulpotomy or extraction procedure in primary molars.

Background: Proper treatment of carious primary teeth is of particular importance in order to prevent oral infections. This is also because primary teeth play a very important role in proper mastication and in maintaining space in the arch for the permanent teeth. Pediatric aesthetic dental procedures are often done for reconstructive or cosmetic purposes. The Hall technique is a conservative alternative treatment for carious primary molars developed by Dr. Norna Hall in the 1980s. Aim: The aim of the present study was to evaluate the effectiveness of acrylic crown to restore carious maxillary primary incisor, following the Hall technique guide, with clinical follow-ups carried out after 3, 6 and 12 months. Materials and Methods: Ten healthy children aged 2-4 years of both genders, with extensive carious maxillary incisors were involved in this study. Acrylic crown was performed to restore carious incisor without caries removal. Instructions on oral hygiene and appliance maintenance were given to the parents. Results: Fracture of the crowns was not reported in the cases recorded during any of the recall visits. Retention of the crowns was observed to be good in 100% (N=10) of the cases during the 3, 6 and 12 months follow-up, whereas only 10% of the cases showed poor retention at the 6 months follow-up, that needed re-cementing. Based on the statistical analysis, parental satisfaction was observed to have significantly increased with the progression of time for all the considered parameters. Conclusion: The study leads to the conclusion that the simple technique of aesthetically restoring the carious primary maxillary incisors allows it to be used in daily clinical practice with a higher rate of success and satisfaction to the child and parent.