Is there a relationship between juvenile idiopathic arthritis and periodontitis?

AIM: The aim was to compare the prevalence of periodontal conditions in patients with juvenile idiopathic arthritis (JIA) (n=78, age 14.4 years) with those revealed in a healthy control group (n=75, age 15.5 years). MATERIAL AND METHODS: In both groups, the approximal plaque index (API), the modified sulcular bleeding index (SBI), and the clinical attachment loss (CAL) were determined. Laboratory parameters for JIA activity included the capsule-reactive protein (CRP) and the immunoglobulins A, G, M. RESULTS: JIA patients had a significantly higher API (64.6%versus 49.9%, p=0.004) and slightly higher mean percentages of sites with CAL>3.5 mm (0.58%versus 0.22%, p=0.041). There was no significant difference in the prevalence of patients and controls who had sites with CAL >3.5 mm (25.6%versus 17.3%, p=0.212). The mean CAL was slightly greater (0.2 mm; p=0.030) in patients with CRP> or =5.0 mg/l compared with patients with CRP<5.0 mg/l. Patients who took non-steroidal anti-inflammatory drugs (NSAIDs) had a significantly decreased SBI (26.2%versus 51.1%, p=0.019). CONCLUSION: After adjustment for microbial plaque, JIA is not a risk factor for periodontitis.     

3H]-forskolin binding sites in rat submandibular salivary glands

Specific [3H]-forskolin binding was linear as a function of the membrane protein concentration and reached steady-state by 30-40 min of incubation at 37 degrees C. Such binding was saturable and the bound radioligand could be readily dissociated by an excess of unlabelled forskolin. There was only one type of binding site, with a dissociation constant (Kd) of 0.16 microM. The concentration of the binding sites (Bmax) was 0.73 pmol/mg protein. There was no significant difference in the [3H]-forskolin binding characteristics in membranes of rats fed for 6 weeks on diets containing 10% corn oil, 8% coconut oil + 2% corn oil, or 10% menhaden fish oil.     

Mixed dentition analysis in a Jordanian population

OBJECTIVE: To examine the applicability of the Tanaka and Johnston method of prediction in a Jordanian population and to develop a new prediction method for this specific population if necessary. MATERIALS AND METHODS: Three-hundred and sixty-seven Jordanians (193 female, 174 male, mean age 15.5 years) were randomly selected to represent 0.1% of 10th grade schoolchildren from Amman, Jordan. The mesiodistal crown diameters of the permanent teeth were measured and compared with the predicted values derived from the Tanaka and Johnston equations. RESULTS: Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and that of the maxillary and mandibular canines and premolars were found to be 0.60 and 0.66, respectively. There were significant differences between the actual measurements and measurements derived from the Tanaka and Johnston equations. New linear regression equations were derived for both genders to allow tooth size prediction in Jordanians. CONCLUSIONS: There is a limitation in the application of the Tanaka and Johnston's prediction method to a Jordanian population. It is important to use separate equations for male and female patients.     

The fatigue life of a cobalt-chromium alloy after laser welding

The aim of this study was to investigate the fatigue life of laser welded joints in a commercially available cast cobalt-chromium alloy. Twenty rod shaped specimens (40 mm x 1.5 mm) were cast and sand blasted. Ten specimens were used as controls and the remaining ten were sectioned and repaired using a pulsed Nd: YAG laser welder. All specimens were subjected to fatigue testing (30N - 2Hz) in a controlled environment. A statistically significant difference in median fatigue life was found between as-cast and laser welded specimens (p < 0.001). Consequently, the technique may not be appropriate for repairing cobalt chromium clasps on removable partial dentures. Scanning electron microscopy indicated the presence of cracks, pores and constriction of the outer surface in the welded specimens despite 70% penetration of the weld.     

Pilomatrixoma imitating infantile hemangioma

Many lesions can masquerade as infantile hemangioma, the most common tumor of infancy. We describe an infant with pilomatrixoma mimicking hemangioma. The patient presented at 8 months of age with an 1.2-cm, red, asymptomatic lesion of the right ear. The mass was noted at 4 months of age and subsequently enlarged. Ultrasonography demonstrated hypervascularity "consistent with infantile hemangioma," and the infant was observed. At 12 months of age, the lesion continued to expand and became ulcerated; it was excised, and histopathology showed pilomatrixoma. Diagnostic confusion was caused by atypical features of this pilomatrixoma that overlapped with infantile hemangioma: onset in infancy, ulceration, red color, and fast flow on imaging. Deviation from the predictable clinical features of an infantile hemangioma should prompt consideration for other types of pediatric lesions, including pilomatrixoma.     

Effect of cementation,cement type and vent holes on fit of zirconia copings

Objectives

To investigate the effect of cementation, cement type and vent-holes on the marginal and internal fit of Zirconia (Zr) Copings.

Geometric and mathematical proportions and their relations to maxillary anterior teeth

AIM: One of the critical aspects of esthetic dentistry is creating geometric or mathematical proportions to relate the successive widths of the anterior teeth. The golden proportion, the recurring esthetic dental (RED) proportion, and the golden percentage are theories introduced in this field. The aim of this study was to investigate the existence of the golden proportion, RED proportion, and the golden percentage between the widths of the maxillary anterior teeth in individuals with natural dentition. METHODS AND MATERIALS: Standardized frontal images of 376 dental student smiles were captured. The images were transferred to a personal computer, the widths of the maxillary anterior teeth were measured, and calculations were made according to each of the above mentioned theories. The data were statistically analyzed using paired student T-test (level of significance P<0.05). RESULTS: The golden proportion was found to be accurate between the width of the right central and lateral incisors in 31.3% of men and 27.1% of women. The values of the RED proportion were not constant, and the farther the one moves distally from the midline the higher the values. Furthermore, the results revealed the golden percentage was rather constant in terms of relative tooth width. The width of the central incisor represents 23%, the lateral incisor 15%, and the canine 12% of the width of the six maxillary anterior teeth as viewed from the front. CONCLUSIONS: Both the golden proportion and the RED proportion are unsuitable methods to relate the successive widths of the maxillary anterior teeth. However, the golden percentage theory seems to be applicable to relate the successive widths of the maxillary anterior teeth if percentages are adjusted taking into consideration the ethnicity of the population.     

Outcomes and complications based on experience with resorbable plates in pediatric craniosynostosis patients

The structure and functional relationship of polymers have long been the purview of engineers and polymer chemists. Bioabsorbable fixation devices have been used for decades as dissolvable suture meshes and, recently, routinely by orthopedic surgeons. During the past decade, bioabsorbable fixation systems have become available for use by craniomaxillofacial surgeons for cranial vault remodeling. This study evaluates the application of a bioabsorbable fixation system in reconstructive craniofacial procedures in a pediatric population. We reviewed 146 cases of cranial vault reconstruction including 98 boys and 48 girls ranging from 2 months to 16 years (mean, 15 months) in age. The procedures were performed for 6 years between January 1998 and June 2004. Bioabsorbable plates and screws were used in each case; most of these cases were craniosynostosis reconstructions. There were 69 cases of frontal sagittal craniosynostosis, 36 metopic, 20 unicoronal, 12 bicoronal, 5 lamboid, 2 deformational plagiocephaly, and 2 multiple fusion of sutures. Postoperative evaluation consisted of clinical examination and three-dimensional computed tomography scan reconstructions at 3, 6, and 12 months. Items specifically screened for on the clinical examination included wound healing, signs of infection, and palpability of implant through the skin. Six patients had palpable plates, 2 patients had palpable screw, and 5 patients had infection at the incision site (of which only 3 were treated with inpatient care including incision drainage and intravenous antibiotics). Our experience has been overwhelmingly positive, and we feel that our results suggest that resorbable fixation is a superior option in pediatric plastic and craniofacial surgery.