Dental age related tables for children of various ethnic groups in South Africa.

The standard age estimation methods of Moorrees, Fanning & Hunt (1963) and that of Demirjian, Goldstein & Tanner (1973) have been shown by several authors to be inaccurate when applied to their juvenile population. This was similarly found to be true in South African children. Pantomographic radiographs of samples of South African children of White, Coloured, Indian and Black origin were used to develop dental age related tables for these ethnic groups. These dental age estimation tables were tested and are presented.

Testing standard methods of dental age estimation by Moorrees, Fanning and Hunt and Demirjian, Goldstein and Tanner on three South African children samples.

Dental age estimation of juvenile skeletal remains has utilized the methods of Moorrees ,Fanning and Hunt (1963) [MFH] and Demirjian,Goldstein and Tanner (1973) [DGT] for many years with various results. The Demirjian et al method has been tested by several authors on their population groups with varying results.The use of these methods to age the skeletal remains of South African children by the author has not been successful. The aim of this study was to test the accuracy of the dental age estimation methods of MFH and DGT on samples of children of different ethnic groups.The study showed that the MFH method consistently under-estimates the age and the method of Demirjian et al over-estimates theages.

[Microleakage of four different amalgam binding systems]. / Mikrolekkasies van vier verskillende amalgaambindingsisteme.

This-study was undertaken to evaluate and compare microleakage in class V cavities in human teeth which were lined with Amalgambond Plus with HPA (Parkell, USA), Optibond Solo (Kerr, U.S.A.), Fuji Plus (GC Corporation, Japan) and Prime & Bond 2.1 (Dentsply, Switzerland), and then restored with Logic amalgam (SDI Australia). The restored teeth were thermocycled in basic fuchsin dye, sectioned, and evaluated for dye penetration. The interdiffusion zones were viewed in a confocal laser scanning microscope (CLSM). The results showed that no bonding system could totally eliminate microleakage. Statistical analysis revealed significant differences between Amalgambond Plus with HPA and Prime & Bond 2.1, Fuji Plus as well as Optibond Solo, for both the enamel and dentine sides. No significant differences were found between Prime & Bond 2.1, Fuji Plus and Optibond Solo, for both the enamel and dentine sides. Amalgambond Plus showed significantly more leakage at dentine sides while Prime & Bond 2.1 showed significantly more leakage at enamel sides. The CLSM revealed hybrid layers of different thicknesses, resin penetration into tubules, as well as resin incorporation within the spherical particles of the amalgam. Optibond Solo, Fuji Plus and Prime & Bond 2.1 can serve to improve the marginal seal of amalgam restorations.

Shear bond strength, microleakage, and confocal studies of 4 amalgam alloy bonding agents.

OBJECTIVE: This study was undertaken to determine the relative shear bond strengths and microleakage of 4 bonding agents to dentin and amalgam and to investigate the bonding to dentin through confocal laser scanning microscopy. METHOD AND MATERIALS: Sixty noncarious molars were restored with 1 of 4 different systems, and the shear bond strengths were determined. For the microleakage study, Class V amalgam restorations were placed in 60 noncarious teeth. The specimens were thermocycled, the teeth were sectioned, and dye penetration was assessed. For confocal examinations, the first component of the bonding adhesives was labeled with rhodamine B. Each of the adhesives was applied to 3 dentin specimens, which were examined under a confocal laser scanning microscope RESULTS: Of the 4 restorative systems tested, AmalgamBond Plus + HPA and Prime & Bond 2.1/base-catalyst showed significantly higher shear bond strengths. Prime & Bond 2.1/base-catalyst had the lowest microleakage value, which was significantly lower than that of AmalgamBond Plus + HPA and AmalgamBond Plus. AmalgamBond Plus + HPA had the highest variation in both the bond strength and microleakage values. Confocal laser scanning microscopy revealed tag formation, penetration of the bonding agents deep into the tubules, and hybrid layer formation for all 4 bonding systems. CONCLUSION: The 2 best systems, Prime & Bond 2.1/base-catalyst and, to a lesser extent, AmalgamBond Plus + HPA, utilized a supplemental bonding agent.

In vitro, relative microleakage of five restorative systems.

The purpose of this study was to determine the relative microleakage of five restorative systems when bonded to dentine/cementum. For the microleakage determination Class V cavity preparations were prepared on the facial surfaces of 65 teeth (10-15 for each material) below the cemento-enamel junction and restored. The root apices were sealed, the teeth coated with nail varnish except for 1 mm surrounding the restorations and the specimens were thermocycled (x500) in 2 per cent methylene blue solution. Root sections including the restorations were dissolved in acid and the concentrations of the dye determined spectrophotometrically. The sequence of the microleakage values were: Dyract < OptiBond < AeliteBond < All-Bond 2 < ScotchBond. It is concluded that Dyract had the lowest microleakage at dentine/cementum interface, which may increase the longevity of the restorative in the clinical situation, with no, or less secondary caries.

A comparison of fluoride release from various dental materials.

OBJECTIVE: The aim of this study was to determine, in vitro, the relative short- and long-term fluoride release from four resin-modified glass ionomers (Fuji II LC, Vitremer, Enforce & Advance), a polyacid-modified composite resin (Dyract compomer) and a bonding agent (OptiBond). METHODS: All the materials were prepared as outlined by the manufacturers. Circular discs of the materials mentioned were suspended in water for up to 300 days and the non-cumulative 24-h fluoride release was determined potentiometrically at chosen times. RESULTS: The amounts of fluoride released during the first day were Vitremer (1.46 micrograms mm-2), Advance (1.18 micrograms mm-2), Fuji (1.08 micrograms mm-2), Optibond (0.33 microgram mm-2), Dyract (0.31 microgram mm-2) and Enforce (0.15 microgram mm-2). After the second day the sequence changed slightly and remained approximately the same for the rest of the 300-day period. There was also an increase in the fluoride release during the 60-200-day period relative to the previous period. CONCLUSION: In general the most fluoride was released by Advance and not by Fuji II LC or Vitremer. For most materials, fluoride is still released after 300 days. Furthermore, even a thin layer of bonding agent released a relatively high amount of fluoride (volume-wise the most) at the beginning. It is deduced that even the release of relatively low amounts of fluoride may result in significant concentrations of fluoride in a microleakage gap.

Relative shear bond strength and microleakage of two dentine bonding agents.

We determined the relative shear bond strength (SBS) to dentine and cementum and the microleakage of All-Bond 2 universal dental adhesive and OptiBond multi-use filled adhesive. We found that for both systems the SBS increased significantly (p < 0.001) from 15 minutes to 24 hours and 7 days, but there was a slight significant (p < 0.001) weakening towards 30 days. At each time point the shear bond strength of All-Bond 2 and OptiBond were also compared and it was found that OptiBond had significantly higher values (p < 0.05) at all times except at 15 minutes. Optibond also had the lower value for the microleakage (p < 0.001). This study showed that OptiBond had significantly higher shear bond strengths to and lower microleakage in dentine which may increase the longevity of the material in the clinical situation.

Root caries in a sample of elderly persons.

With the anticipated increase in the aged adult population and the associated gingival recession, the prevalence of root caries is expected to increase. The purpose of this study was to determine the experience and distribution of root caries in a group of aged adults living in Kayelitsha. All non-institutionalized elderly black adults participating in a community geriatric programme were examined. Root caries was recorded using visual and tactile criteria and expressed as the root caries index (RCI) rate. The mean age of the subjects was 65.2 years, the mean number of teeth present was 17.3 and the mean RCI rate was 2.2 per cent. All subjects had gingival recession while only 23.8 per cent had root caries. No surfaces with restored root caries lesions were found. In the maxilla the highest RCI rate was observed on the interproximal surfaces of the posterior teeth (4.4 per cent) but in the mandible the buccal surfaces of the posterior teeth had the highest RCI rate (4.2 per cent). In both the maxilla and the mandible the lingual surfaces of the anterior teeth showed no root caries. Maxillary teeth did not have a significantly higher root caries attack rate than mandibular teeth. Root caries does not appear to be a public health problem in the sampled population.

Metacarpal bone mass in systemic lupus erythematosus.

We report the prevalence of metacarpal cortical thinning in systemic lupus erythematosus (SLE). Fifty-eight ambulant female patients attending a lupus clinic (mean age 32.4 years), were found to have significant thinning of metacarpal cortices (p < 0.05) when compared with 63 normal females (mean age 34.1 years). However, metacarpal bone mass was within the normal range. Measurements were made at 6 metacarpals of the 2 hands using a computer-aided technique (digitized radiogrammetry). Femoral cortical width and Singh index at the left femur, as well as the vertebral index at L3 were also recorded. The trabecular indices were in the range of normality, but the SLE group had more patients in the immediately pre-osteopenic range. Metacarpal bone loss was not related to disease duration or corticosteroid therapy. The prevalence of osteopenia in SLE is probably underestimated and the pathogenesis is likely to be multifactorial.

[Fluoride concentration in drinking water in small villages in the Cape province]. / Die fluoriedkonsentrasie in die drinkwater van kleiner dorpe in die Kaapprovinsie.

The purpose of the study was to update existing tables on the fluoride content of drinking water and thereby help curb its fluoride overdose from the use of fluoride containing tablets. The fluoride concentration in the drinking water of 57 villages in the Cape Province was determined by a combination fluoride ion selective electrode. This investigation showed that the number of available water sources decreased as follows: boreholes greater than dams greater than fountains = canals. Furthermore, boreholes contained more fluoride in the drinking water than fountains, dams or canals (p less than 0.10). Five out of 41 boreholes have less than or equal to 0.10 parts per million (ppm) fluoride in the drinking water, while 17 out of 26 dams, 4 out of 13 rivers and 3 out of 5 fountains and canals contained less than or equal to 0.10 ppm fluoride.

An adaptation of the Moyers mixed dentition space analysis for a Western Cape Caucasian population.

200 dental plaster casts of Western Cape Caucasoid subjects, all of whom were under the age of 21 years, were used in this study. Mesio-distal measurements (MD lengths) were obtained of all the teeth, disregarding the third molars. This data was used to develop regression equations, for maxillary and for mandibular arches, to enable the prediction of the mesio-distal lengths of the canine and two premolars. The study identified the sum of the MD lengths of the permanent lower incisors as the best predictor. It appears that separate predictions for male and female are not warranted. The equations and the predicted values were compared with those of Moyers (1973 and 1988) and some significant differences were found. The Prediction Tables will be useful in analysis of the mixed dentition phase in patients from this population group.

Analysis of the diets of 12-year-old children in Cape Town.

As very few data are available regarding the nutrient intake of South African children, a dietary survey was conducted among 843 12-year-old children in Cape Town. Trained interviewers used a 24-hour-recall questionnaire developed for this purpose, inserting the quantity and types of foods consumed during different periods of the day on both a weekday and Sunday. The intake of carbohydrate, protein and fat was always greatest for white males and lowest for black males. This difference was emphasized by the high weekday energy intake of white boys (10 577 kJ), in contrast with the low energy intake of the black boys (6 457 kJ). The findings on kilojoule, carbohydrate, protein, fat and fibre content of the diets of these subjects are presented.

Photoparoxysmal responses in the electroencephalograms of some ethnic groups of the Cape Peninsula.

A comparative investigation of the frequency of photoparoxysmal responses (PPR) in the white, mixed and African populations of the Cape Peninsula is presented, based on 9697 consecutive referrals for EEG. PPR were observed in 2.5% of the white, in 1.3% of the mixed and in 0.9% of the African population groups. In the present material there were more patients with epilepsy in the mixed than in the white group, the frequencies changing with age in the two groups. Minor interrelationships of PPR exist with sex, age and race considered separately. Another minor relationship could be demonstrated between PPR and epilepsy. Three-factor interaction exists among epilepsy, age and race, and a further three-way interaction could be shown among sex, age and epilepsy. These relations and interactions were all significant below the 1% level. Standard EEG records (including response to hyperventilation) sensitivity limits to PPR, and the types of seizures themselves, did not differ significantly between the two main ethnic groups.