Influence of silicate cement restorations on gingiva

The influence of surface finish and in-vitro pellicle on contact-angle measurement and surface morphology of three commercially available composite restoratives

Three commercially available composites (Concise, Occlusin and Heliomolar) had surface finishes of varying roughness. Concise and Occlusin were cured against glass and Mylar, or were polished with a white stone or Soflex discs, producing four different surface finishes. Heliomolar was cured against glass or finished with a Vivadent polisher. Each specimen was immersed in water (without pellicle) or artificial saliva (with pellicle) and photographed with a captive air bubble. The influence of pellicle on contact-angle measurements and hence adhesiveness was determined. Scanning electron microscopy of pellicle-free and pellicle-conditioned surfaces was also performed. The effect of the pellicle on all Concise specimens was profound, tending to increase adhesiveness of the smooth (glass and Mylar) surfaces and decrease adhesiveness of the roughened (white stone and Soflex disc) polished surfaces. The pellicle-conditioned smooth Occlusin surfaces behaved similarly, but not the polished specimens, having similar contact-angle measurements after pellicle deposition. Heliomolar had significantly reduced contact-angle measurements after pellicle formation, and thus increased adhesiveness. The influence of the pellicle on surface finish characteristics may be significant, and may vary according to the composite used.

Effects of the degree of overbite and overjet on dental health

The purpose of the study was to examine whether any combination of vertical overbite (OB) and horizontal overjet (OJ) may be more favourable than others to dental health in anterior segments. The study group consisted of 74 females and 70 males. The participants were 15-years-old and had 6 anterior teeth in both jaws. The following parameters were assessed: plaque index, gingival index, probing depth, space index, filled surfaces, the number of non-aligned proximal tooth surfaces (NONAS) and the OB/OJ ratio. The results demonstrated that participants with a relatively high OB/OJ ratio (OB/OJ greater than or equal to 1.21) had a more favourable periodontal condition than participants with lower ratios. This was so in both sexes and both jaws. The OB/OJ ratio had little relation to the prevalence of filled surfaces.

Relationship between alignment conditions of teeth in anterior segments and dental health

The purpose of the study was to examine the association between alignment conditions of anterior teeth and dental health in 15-year-old adolescents. The study group consisted of 74 females and 70 males with 6 anterior teeth in both jaws. The following parameters were assessed: plaque index (P1I), gingival index (GI), probing depth (PD), space index (SpI), filled surfaces (FS), and the NONAS-i.e., the number of non-aligned proximal tooth surfaces in each jaw counted on model casts. Statistical examination of the data was performed using chi 2 tests of association and homogeneity and correlation coefficient analyses. In both sexes and both jaws, anterior tooth segments with none or few non-aligned teeth had a more favourable periodontal state than segments with an increased number of non-aligned teeth. Likewise, tooth segments with none or few non-aligned teeth had a reduced frequency of proximal fillings compared to segments with an increased number of non-aligned teeth. In males, the distribution of restorations in the anterior segment of the lower jaw was relatively homogeneous in the 3 groups.

Effects on dental health of spacing of teeth in anterior segments

The purpose of the study was to examine the relationship between spacing and dental health in 15-year-old adolescents. The whole sample consisted of 156 subjects. Out of them, 74 females and 73 males with 6 anterior teeth made up the study group for examination of the upper jaw. 75 females and 75 males had 6 anterior teeth in the lower jaw and made up the study group for examination of the lower jaw. The Plaque Index (PlI) and the Gingival Index (GI) were recorded. Probing depths (PD) were measured as explained by Glavind & Løe. Filled surfaces (FS) were taken from the individual case sheets and controlled clinically. The spacing of the individuals was assessed by counting the number of proximal surfaces without visible contact with the adjacent proximal surfaces, on model casts. The sum of proximal surfaces without contact made up the Space Index (SpI) of the individual jaw. Parametric and non-parametric statistical methods were used to analyze the data. In both sexes and both jaws proximal surfaces without interdental contact had a more favourable periodontal condition than surfaces with contact. In the upper jaw of both sexes, proximal surfaces without interdental contact had a reduced number of filled surfaces compared to surfaces with contact. The linear relationship between SpI and FS was significant, i.e., an increased number of surfaces without contact was accompanied by a reduced number of filled surfaces. In the lower jaw, the differences between the SpI groups and the linear relationship between SpI and FS did not reach significance. In both sexes and both jaws, proximal surfaces without fillings had a more favourable periodontal state compared to surfaces with fillings. Indications are that the summation effect of the presence of interdental contact and the presence of fillings contributed to the differences in periodontal condition between surfaces with and without interdental contact.

Tooth colored dental restorative materials: porosities and surface topography in relation to bacterial adhesion

The present investigation was carried out to determine whether differences in initial bacterial accumulation on dental restorations could be explained by differences in surface topography, particularly porosities, of the materials. A point counting method was used to determine the number and the size of the porosities in 15 materials. The results demonstrated great variation among the materials in the number of porosities. However, in vitro bacterial adhesion tests failed to show any relationship between porosities in the materials and the number of bacteria adhering to them. Nor were differences in surface topography, as measured profilometrically, associated with differences in bacterial adhesion. It is concluded that variations in surface topography including porosities do not suffice to explain differences in initial bacterial accumulation on silicate cements and composite dental restoratives.

The periodontium and restorative procedures. A critical review

The literature associated with the effect on the periodontal tissues of restorative procedures has been reviewed. Opinions have changed from the assumption that only poor restorative dental treatment led to periodontal disease, to the present concept, that even clinically sound restorations, if positioned subgingivally, may be important aetiological factors in the initiation of periodontal disease.

Excessive crown contours facilitate endemic plaque niches

Facial and lingual surfaces of teeth restored with complete metal and porcelain-fused-to-metal crowns exhibited greater mean plaque accumulation than did the contralateral teeth. This cross-sectional study showed greater facial-lingual width and plaque indices for restored teeth than for natural or unrestored teeth. This relationship between plaque and excessive contours must not be considered wholly dependent and conclusive. The multifactorial phenomenon influencing plaque accumulation no doubt could contribute to the findings of this study. However, until demonstrated otherwise, the creation of artificial crown contours that are greater than natural tooth convexities must be considered another parameter promoting endemic plaque niches. Sound application of principles with respect to the form of teeth and supporting tissue can preclude contouring of restorations beneficial to the accumulation of dental plaque.

Effects of artifical crown margin extension and tooth brushing frequency on gingival pocket depth

The gingival tissues adjacent to the crowned and unrestored teeth were probed to determine individual pocket depths. The findings are listed here. (1) The average pocket depth adjacent to nonrestored teeth was 2.7 mm. The average pocket depth adjacent to teeth having crowns with subgingival margins was 3.4 mm. (2) Fifty-four nonrestored teeth had at least one pocket depth greater than 3 mm., while 84 crowned teeth had at least one or more measurements greater than 3 mm. (3) No positive relationship could be found between tooth brushing frequency and the pocket depth adjacent to teeth restored with complete cast crowns. (4) In nonrestored teeth, pocket depth increased with reduced frequency of tooth brushing. (5) Pocket depth increased with increased age of (a) the patient in both restored and nonrestored teeth and (b) the cast crown.