National oral health survey Zimbabwe 1995: quality of restorations.

In 1995, a second national oral health survey was carried out, ten years after the first. Application of a multi-stage sampling procedure resulted in 3709 persons being examined. The restorations were assessed using the criteria described by Kroeze et al (1990). Only ditches on the tooth/restoration margins that were wider than 0.4 mm were considered to be carious. The background variables studied were age, gender, type of location, socioeconomic status (SES) and level of education. The prevalence of restorations in all persons examined was 3.4 per cent. Restorations were found much more often among urban (95.5 per cent) than rural people (4.5 per cent) and also among those living in high (75 per cent) compared to low SES suburbs (25 per cent). Amalgam was more often used (89 per cent) than composite resin (10 per cent). The most frequently observed type of restoration was Class I (45 per cent) followed by Class II (39 per cent) and Class III (7 per cent). The prevalence of satisfactory restorations was 83.9 per cent. Failures were due to 'fractured restorations' (6.3 per cent), 'caries at the margin' and 'breakdown of restoration margin', both 4 per cent. Amongst adults, multiple-surface amalgam restorations failed more often than single-surface ones. It is concluded that the prevalence of restorations found was very low. There is a need to extend the provision of preventive and restorative oral health care by a more equitable distribution of oral health personnel and by making more finance available to rural and low-SES suburban areas.     

Validation of micro-CT against the section method regarding the assessment of marginal leakage of sealants

Background: The aim of this study was to validate the micro‐CT and related software against the section method using the stereomicroscope for marginal leakage assessment along the sealant‐enamel interface. Methods: Pits and fissures of the occlusal surface of 10 teeth were sealed with a resin‐fissure sealant material without acid etching, thermocycled for 5000 cycles, immersed in 50% silver nitrate for three hours and scanned using micro‐CT. Teeth were embedded in epoxy resin and cut in three sections. The middle section was subjected to micro‐CT and stereomicroscopy. Images were taken from the left and right sides of the sealant‐enamel interface at both the left and the right site of the section. Two experienced evaluators assessed marginal leakage. Results: Both assessment instruments observed no leakage in 37 out of the 40 images evaluated. Leakage at the sealant‐enamel interface was observed in three stereomicroscopy images only. A fracture line in the sealant was seen on eight stereomicroscopy images and observed in only two micro‐CT images. Conclusions: The quality of the micro‐CT and related software used in the present study does not qualify it to replace the section method as the gold standard for marginal leakage assessment at the sealant‐enamel interface of permanent teeth.     

Randomized clinical trial of class II restoration in permanent teeth comparing ART with composite resin after 12 months

Clinical Oral Investigations - This study evaluated the effectiveness of class II restorations, in permanent teeth, through the ART technique in comparison to composite resin. Participants (154),...     

Amalgam and ART restorations in children: a controlled clinical trial

Objectives

The aims of this study were to compare 2-year cumulative survival rates of amalgam and atraumatic restorative treatment (ART) restorations in primary molars and to investigate the determinants of the survival rate of restorations.

Materials and methods

A controlled clinical trial using a parallel group design was carried out on 258 children aged 6–7 years old, allocated to two treatment groups: conventional restorative treatment using amalgam and ART using high-viscosity glass ionomer. A total of 364 amalgam restorations and 386 ART restorations were placed by three pedodontists in 126 and 158 children, respectively, and were evaluated after 0.5, 1, and 2 years. Restorations were placed in vital primary molars with neither pain nor signs of pulp involvement. The survival analysis was conducted using the proportional hazard rate regression model with frailty correction.

Results

The 2-year cumulative survival rates for all amalgam (77.3 %) and ART (73.5 %) restorations were not statistically significantly different, but there was an effect of “type of surface” (single/multiple) and “cavity filling time” on the survival rates. Both amalgam and ART single-surface restorations had higher survival rates than multiple-surface restorations of the same material. Secondary caries was responsible for 36 and 38 % of failures in amalgam and ART restorations, respectively. Mean time for restoring all type of cavities with amalgam and ART restorations was 13.6 and 13.7 min, respectively.

Conclusions

Amalgam and ART restorations presented similar survival rates over a 2-year period for all, single-surface, and multiple-surface restorations.

Clinical relevance

In the cause of finding alternatives to amalgam, ART restorations using high-viscosity glass ionomer might be a suitable option for managing cavitated dentine carious lesions in vital primary molars.     

Microleakage and sealant penetration in contaminated carious fissures

Objectives

The aim of the present in vitro study was to evaluate the effect of an adhesive system on microleakage and sealant penetration depth in carious fissures after different surface contamination circumstances.

Methods

Extracted third molars (n = 128) with small occlusal cavitated carious lesions were randomly divided into eight experimental groups and sealed under four different surface conditions. 1, Dry conditions; 2, water contamination; 3, saliva contamination; 4, saliva contamination and air-drying. Two sealant protocols were applied, one using a fissure sealant (Teethmate F) and one using an additional adhesive system (SA primer and Photo Bond). The control group consisted of sound third molars (n = 16), that were sealed under dry conditions. After thermocycling (n = 500 cycles), teeth were immersed in 1% methylene blue for 24 h, sectioned and digitally photographed. Microleakage was evaluated on a three-point rating scale and analysed using a Chi-square test. Additionally, the presence of caries and incomplete sealant penetration was scored from photographs and analysed using logistic regression.

Results

A statistical significant difference regarding microleakage scores was present between sealed carious and sealed sound fissures. The use of an adhesive system in case of water contamination significantly reduced microleakage (p < 0.05). With regard to sealant penetration depth, there were significant differences present for carious sealed fissures, use of an adhesive system prior to sealing, and water and saliva contamination.

Conclusions

Use of an adhesive system improved the effectiveness of sealants placed after water contamination in carious fissures. However, sound fissures showed less microleakage and better penetration abilities than carious fissures.     

The effect of chronic oral methadone treatment on monkey chorionic gonadotropin, estradiol, dehydroepiandrosterone sulfate, progesterone, prolactin and cortisol levels during pregnancy in the cynomolgus monkey (Macaca fascicularis).

The effect of chronic methadone treatment upon the serum levels of Estradiol (E2), Progesterone (P), Prolactin (Prl), monkey chorionic gonadotropin (mCG), dehydroepiandrosterone sulfate (DHEAS) and Cortisol (C) in pregnant Cynomolgus monkeys (Macaca fascicularis) is described in comparison with the hormone levels in a control group. Only DHEAS was significantly decreased in late pregnancy in the methadone group. From these data it can not be concluded that methadone treatment compromises (feto)placental function. The observed intra-uterine growth retardation in the methadone treated group might be a result of a direct influence of methadone upon growth.     

How effective is ART in the management of dental caries?

The ART approach involves excavating cavitated dentine caries with hand instruments, then restoring the cavity and sealing any associated fissures and pits with an adhesive restorative material, resulting in a sealant restoration. Until recently, ART has mainly been used under field conditions, and thus the adhesive restorative material used has been glass ionomer which does not require mixing machines and curing lights. Since the inception of ART, a growing number of studies world-wide have taken place. A total of four studies have reported 3-year survival percentages for one-surface ART restorations. The highest 3-year survival percentage in permanent teeth was 88%, which is comparable to the 85% survival of one-surface amalgam restorations placed under the same field conditions after 3 years. The outcomes depend to some extent on the material used, operator experience and presence of caries. The presence of caries as a reason for failure was higher in the early than in the most recent studies. Only one study has reported on the use of ART restorations in the deciduous dentition. It is concluded that: a very large proportion of dentine lesions in the permanent teeth can be treated using the ART approach; the 3-year survival rate of the more recently placed one-surface ART restorations in permanent teeth was higher than that of ART restorations placed in the beginning; the survival of one-surface ART restorations in the permanent dentition with newer glass ionomers is comparable to that of one-surface conventional restorations placed using amalgam in a comparable setting after 3 years; more studies of longer duration are needed to confirm these findings; ART should be considered a caries treatment modality that benefits people; and educational courses need to be organised before the approach is applied in the clinic.     

Strength of tunnel-restored teeth with different materials and marginal ridge height

ObjectiveThe aim of the study was to investigate the strength of the marginal ridge of tunnel preparations with different marginal ridge heights, using different restorative materials.Materials and methods120 sound premolars were randomly divided into three groups of standardized tunnel preparations with a remaining marginal ridge height of 1.5 mm, 2.5 mm and 3.5 mm, respectively. In each tunnel group, 10 teeth were filled with all four newly developed adhesive materials that had not previously been used in tunnel preparation: Ketac Aplicap, Fuji IX, Fuji II LC and Beautifil Flow F02. The control group comprised 10 sound teeth. All teeth were subjected to incremental dynamic force testing. Remaining marginal ridge height and restoration material were the independent variables. The mean maximum energy (MEI) score was the dependent variable. Data were analyzed, using one- and two-way analysis of variance. Scheffe's test and Student's t-test were used for comparison between groups.ResultsBoth restorative material (P < 0.0001) and remaining marginal ridge height (P < 0.0001) had a statistically significant effect on the mean MEI score of tunnel-prepared teeth. At the 2.5 mm of remaining marginal ridge height, no statistically significant difference in mean MEI score existed between Beautifil Flow F02-filled tunnel-prepared teeth and sound teeth.SignificancePremolars tunnel-restored with Beautifil Flow F02 at 2.5 mm distance from the marginal ridge were as strong as sound teeth.     

Prevalence of caries, plaque and gingivitis in an urban and rural Tanzanian child population

A longitudinal study of the oral condition of 763 schoolchildren was started in the Morogoro District of the Republic of Tanzania in 1984. The average baseline D3MFT scores of the 7-, 8- and -9-yr-old urban and rural children were 0.27, 0.33, 0.35 and 0.04, 0.23 and 0.23, respectively; the average deft values were 2.9, 2.4, 2.6 and 1.4, 1.9 and 1.4. The permanent dentition was caries free (D3MFT = 0) in 80 and 89% of the urban and rural children, respectively. Gingivitis was prevalent in rural (61%) and urban (55%) children; visible plaque was present in 93% of the children in both subsamples. The results of this baseline study show that the child population under study reflects the national Tanzanian situation with higher caries prevalence in urban than in rural children.