Biomedical subjects

A M Kielbassa

Publications and source records attributed to A M Kielbassa.

At least 19 recordsLinked to original sources

PubMed2006

Microradiographic study on the effects of mucin-based solutions used as saliva substitutes on demineralised bovine enamel in vitro.

Sialic acids and proteins bound to mucins are known to form complexes with calcium, and this mechanism may hamper the remineralization of calcium-containing mucin-based saliva substitutes. Thus, the aim of this investigation was to evaluate the effects of adding various concentrations of calcium phosphate to self-made mucin-containing solutions on demineralised bovine enamel in vitro. Bovine specimens were prepared, embedded in epoxy resin, and polished to 4000 grit. Subsequently, the surfaces of the specimens were partially covered with nail varnish, thus serving as a control of sound enamel, and demineralised (37 degrees C; pH 5.0) for 14 (19 groups; n=10) or 28 days (three groups; n=9). After demineralization, the specimens were exposed to mucin-based solutions (30 g/l) with various saturations with respect to apatites containing 0.1 mM NaF, CaCl(2) (0-20 mM) and KH(2)PO(4) (0-52 mM) at two different pH values (5.5 or 6.5). A fluoride-free solution and the commercially available saliva substitute Saliva Orthana (Orthana, Kastrup, Copenhagen Denmark) served as controls. The differences in mineral loss (DeltaDeltaZ) between the values prior to (DeltaZ(Demin)) and after storage (DeltaZ(Effect)) in the various solutions were evaluated from microradiographs of thin sections (100 microm). The general linear model revealed a significant dependency of DeltaDeltaZ for calcium (P=0.006), but not for phosphate (P=0.081) or pH (P=0.114). DeltaZ(Effect) was only significantly reduced compared with DeltaZ(Demin) in the group with the highest saturation with respect to hydroxyapatite (P<0.05; t-test). In conclusion, mucin-based saliva substitutes with an adequate composition are able to remineralize bovine enamel in vitro.

Animals↗

PubMed2006

Effects of luting agent and thermocycling on bond strengths to root canal dentine.

AIM: To investigate the effects of luting agent and thermocycling on bond strengths to root canal dentine. METHODOLOGY: Extracted maxillary canines (n =144) were root filled and divided into six groups of 24 teeth each. Fibre posts (FRC Postec) were inserted using six luting agents: Panavia F, Multilink, Variolink II, PermaFlo DC, RelyX Unicem and Clearfil Core. Each root was sliced into six discs (thickness 1 mm) representing the coronal, middle and apical part of the root canal. Push-out tests were performed 24 h after post insertion (n = 12) as well as after thermocycling (5000x; 5-55 degrees C, 30 s) (n = 12). Statistical analysis was conducted using analysis of variance (anova) followed by post-hoc comparisons (Tukey-B). The influence of thermocycling on bond strengths was investigated for each material and region separately using t-tests. RESULTS: The bond strengths were significantly affected by the luting agent (P < 0.001), the root position (P = 0.003) and thermocycling (P < 0.001; three-way anova). RelyX had significantly higher bond strengths compared with all other materials (P < 0.05; Tukey-B). The apical region of the root canal had significantly higher bond strengths compared with the middle and coronal region (P < 0.05; Tukey-B). After thermocycling for RelyX a significant increase in bond strengths was detected for the middle and apical region (P < 0.01; t-test, Bonferroni factor 18). CONCLUSIONS: Bond strengths were affected significantly by luting agent and root position. RelyX had higher bond strengths compared with other materials. The apical region of the canals was characterized by significantly higher bond strengths.

Analysis of Variance↗

PubMed2006

Effect of various Ca2+/PO4(3-) concentrations of linseed-based saliva substitutes on enamel in vitro.

Remineralization might be hampered by various polymers used in saliva substitutes. Thus, the present study evaluated the effects of various calcium and phosphate concentrations of linseed-based solutions on the mineral loss of pre-demineralized bovine enamel in vitro. A commercially available saliva substitute (Salinum) based on linseed was tested as well. Enamel specimens were prepared from bovine incisors and embedded in epoxy resin. One-third of each sample was covered with nail varnish (control of sound enamel). After demineralization (37 degrees Celsius; pH 5.0; 14 days) another third of the samples was nail-varnished again. Subsequently, the specimens (n = 10) were exposed to 12 linseed-based solutions (Ca(2+) addition 0-2 mM; PO4(3-) addition 0-3.2 mM) at pH 5.5 and 6.5 as well as to Salinum) for 14 days (37 degrees Celsius). The differences in mineral loss between the values prior to and after the storage in the various solutions were evaluated from microradiographs of thin sections (100 mum). The general linear model revealed a significant dependency for the mineral loss on 'calcium' (P = 0.003), but not on 'pH' (P = 0.397) and 'phosphate' (P = 0.094). Salinum) induced a significant greater mineral loss compared with equivalently saturated solutions (P < 0.05; anova, Bonferroni). The solution with the highest calcium and phosphate concentration showed the greatest mineral gain (P = 0.033; paired t-test). The addition of calcium and phosphate seems to have a positive effect on the remineralizing qualities of linseed-based saliva substitutes.

Animals↗

PubMed2006

Caries and fluorosis in 6- and 9-year-old children residing in three communities in Iran.

OBJECTIVES: The aim of this study was to investigate the caries and fluorosis prevalence among 6- and 9-year-old students in three communities in Iran with varying urbanization and fluoride in piped water. METHODS: Data were obtained from 523 dental examinations of 6- and 9-year olds in an upper middle class district in Teheran (T) (0.3 mg F/l), the city of Semnan (S) (1.3 mg F/l), and the village Dibaj (D) (0.2 mg F/l). RESULTS: Children in the naturally fluoridated town showed slightly higher dmfs/dfs (SD) values for both 6-year olds [S: 9.1 (9.2), T: 7.2 (7.4), D: 7.1 (6.1)] and 9-year olds [S: 6.0 (6.2), T: 4.4 (4.2), D: 5.0 (4.7)], whereas the mean dmft/dft values as well as the numbers of caries-free children were comparable. A lower prevalence of dental restorations was reported for both Semnan and Dibaj compared with Teheran. A higher prevalence of fluorosis [Tooth Surface Index of Dental Fluorosis (TSIF) 3-7] was observed in the naturally fluoridated town compared with the low-fluoridated communities. CONCLUSIONS: The ingestion of naturally fluoridated water (1.3 mg F/l) seemed to have a negligible effect on caries prevalence, but resulted in higher prevalence of dental fluorosis. It is emphasized that the study population was not adjusted for socioeconomic status, availability of dental care nor for exposures to other sources of fluoride. Nevertheless, it can be concluded that caries prevalence in Iran is quite low compared with that in other countries in the Middle East and that the elevated fluoride levels in the drinking water in Semnan may contribute to the development of mild to severe fluorosis.

Child↗

PubMed2006

Progression of sealed initial bovine enamel lesions under demineralizing conditions in vitro.

The use of sealants for the infiltration of proximal enamel lesions could be a promising alternative to the common strategies of remineralization and operative treatment. The aim of the present study was to compare the progression of sealed initial enamel lesions after exposure to a demineralizing solution in vitro. In each of 54 bovine enamel specimens three subsurface lesions were created. Two of the lesions were etched with phosphoric acid and sealed with either a fissure sealant or with various adhesives (1-5) for 15 s or 30 s, respectively, whereas one lesion remained as the untreated control. Subsequently, half of each specimen was covered with nail varnish (baseline) and the other half was reexposed to a demineralizing solution for 14 days (experimental). The specimens were cut perpendicularly to the surface, infiltrated with a low-viscosity fluorescent resin and observed with a confocal laser scanning microscope (CLSM). For lesions sealed with the fissure sealant and adhesives 1-3, the progression of lesion depth (0-31 microm) was significantly decreased (p<0.01; paired t test) compared with the untreated control (57 microm). For the fissure sealant and adhesives 1 and 3 extended penetration times (30 s) resulted in significantly reduced lesion progression compared to 15 s. It can be concluded that filling of the pores in initial enamel lesions with the fissure sealant and adhesives 1-3 can inhibit further demineralization in vitro.

Acrylates↗

PubMed2006

Effects of irradiation on in situ remineralization of human and bovine enamel demineralized in vitro.

The objective of this study was to evaluate the effects of irradiation and surface condition on in situ remineralization of demineralized human and bovine enamel. Specimens (n=96) obtained from 24 human molars and 24 bovine incisors were prepared. The surfaces of half of the specimens were abraded while the others remained natural. Each of the 12 human and bovine abraded and sound specimens was irradiated fractionally up to 46.5 Gy (3.1 Gy/day, 5 days/week), while the remaining samples were not irradiated. Prior to and following the demineralization (pH 5.0; 14 days) all specimens were partly covered with nail varnish (control). After in vitro demineralization 2 irradiated and 2 nonirradiated specimens were inserted into both buccal aspects of 12 intraoral appliances, which were worn by 12 persons for a period of 6 weeks. All samples were brushed twice a day with a fluoride-containing toothpaste. Mineral analyses revealed a significant influence on mineral loss (DeltaZdemin), mineral gain (DeltaDeltaZ), lesion depth (LDdemin), and lesion depth reduction (DeltaLD) of the variables 'material' and 'irradiation' (p<0.05; ANOVA). Reciprocal interactions could be observed between these two variables for DeltaZdemin, DeltaDeltaZ, and LDdemin, due to significantly reduced values found for the irradiated, abraded bovine specimens compared to the nonirradiated ones (p<0.05; Bonferroni post hoc test). It can be concluded that neither irradiation nor abrasion influenced in vitro demineralization or in situ remineralization of the human specimens, whereas abrasion hampered demineralization in irradiated, bovine specimens.

Adult↗

PubMed2005

Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparation.

AIM: To compare ex vivo various parameters of root canal preparation using a manual technique and six different rotary nickel-titanium (Ni-Ti) instruments (FlexMaster, System GT, HERO 642, K3, ProTaper, and RaCe). METHODOLOGY: A total of 147 extracted mandibular molars were divided into seven groups (n = 21) with equal mean mesio-buccal root canal curvatures (up to 70 degrees), and embedded in a muffle system. All root canals were prepared to size 30 using a crown-down preparation technique for the rotary nickel-titanium instruments and a standardized preparation (using reamers and Hedströem files) for the manual technique. Length modifications and straightening were determined by standardized radiography and a computer-aided difference measurement for every instrument system. Post-operative cross-sections were evaluated by light-microscopic investigation and photographic documentation. Procedural errors, working time and time for instrumentation were recorded. The data were analysed statistically using the Kruskal-Wallis test and the Mann-Whitney U-test. RESULTS: No significant differences were detected between the rotary Ni-Ti instruments for alteration of working length. All Ni-Ti systems maintained the original curvature well, with minor mean degrees of straightening ranging from 0.45 degrees (System GT) to 1.17 degrees (ProTaper). ProTaper had the lowest numbers of irregular post-operative root canal diameters; the results were comparable between the other systems. Instrument fractures occurred with ProTaper in three root canals, whilst preparation with System GT, HERO 642, K3 and the manual technique resulted in one fracture each. Ni-Ti instruments prepared canals more rapidly than the manual technique. The shortest time for instrumentation was achieved with System GT (11.7 s). CONCLUSIONS: Under the conditions of this ex vivo study all Ni-Ti systems maintained the canal curvature, were associated with few instrument fractures and were more rapid than a standardized manual technique. ProTaper instruments created more regular canal diameters.

Dental Alloys↗

PubMed2005

Microradiographic study on the effects of salivary proteins on in vitro demineralization of bovine enamel.

The aim of this investigation was to evaluate the effects of various proteins on in vitro demineralization of bovine enamel. From each of 100 bovine incisors two samples were prepared. The specimens were embedded in epoxy resin and polished up to 4000 grit. Subsequently, the specimens' surfaces were partly covered with nail varnish, thus serving as control of sound enamel. The specimens were divided randomly into five groups (n = 40) and demineralized in a solution of constant composition (pH 5.0; 10 days). For each subgroup of specimens (n = 10) 4 L were taken and either low (50% of medium conc.), medium, or high (150%) concentrations of the proteins [human albumin (100% conc. = 7 mg L(-1)), mucin (577.5 mg L(-1)), immunoglobulin G (IgG) (46 mg L(-1)), casein isolated from bovine milk (1.2 g L(-1))] or amino acid [l-Proline (7 mg L(-1))] were added to 1 L of the demineralizing solution, whereas 1 L served as control. Mineral loss and lesion depth (LD) were evaluated from microradiographs of thin sections (110 mum) by a dedicated software package (TMR 1.24). No differences were found between the five control groups (P > 0.05; ANOVA). Albumin, l-Proline, and IgG did not affect enamel demineralization, whereas the addition of both casein and mucin resulted in significant reductions of both mineral loss and LDs (P < 0.01; Tukey's test). Within the limitations of an in vitro study, the present investigation indicates that casein and mucin seem to affect enamel demineralization significantly. Thus, these proteins might be helpful as an additive to saliva substitutes or mouthwashes if the quality of saliva is altered.

Albumins↗

PubMed2005

Filament end-rounding quality in electric toothbrushes.

OBJECTIVES: A good quality of filament tips is desirable to protect both gingiva and dental hard tissues. The aim of the present study was to compare the end-rounding quality of the filaments in 15 electric toothbrushes (Rowenta dentaclip ZH-07, dentaclip ZH 010, rotaclip ZH-11; Blend-a-dent Wellenprofil 2000 hart, Wellenprofil 2000 mittel-weich, Medic for kids; Broxo; UltraSonex; Krups 548, Waterpik BH-4U; Butler Gum; Dr. Best e-Flex3; Oral-B (EB3, EB 17-8, Plak Control Kids)). MATERIAL AND METHODS: From each brand five brushes were chosen randomly. Five tufts were selected from each brush and studied with a scanning electron microscope (x 45) at a viewing angle of 45 degrees. The filament tips were numbered from top left to bottom right and selected filaments were judged by a well-trained, blinded second examiner according to the Silverstone & Featherstone method. RESULTS: Nine of the 15 brands examined showed a high ("acceptable": >89%), four products a medium (76-84%) and two a bad (34-38%) end-rounding quality. CONCLUSION: A good quality of filament tips is claimed by the dental profession to protect both gingiva and dental hard tissues from abrasion. This could be observed for 13 of the 15 brands examined.

Chi-Square Distribution↗

PubMed2005

[The penetration of various adhesives into early enamel lesions in vitro].

The aim of the present study was to evaluate the penetration depth (PD) and the thickness of the oxygen inhibition layer (OIL) of a fissure sealant (Helioseal, Vivadent) and various adhesives (Heliobond, Excite, Vivadent; Resulcin, Merz; Solobond M, Voco; Prompt L-Pop, 3M-Espe) applied to enamel lesions in vitro. From 27 bovine teeth 54 enamel specimens were prepared and covered with nail varnish (control) thus obtaining three windows for treatment. After demineralisation (pH 5.0, 14 d) two of the windows were etched with phosphoric acid (20%, 5 s), whereas the third area served as control. The specimens were divided randomly into six groups (n = 9) and the respective adhesive was applied (90 s), either once or twice. Light-curing followed each application. Enamel slabs (perpendicular to the surface) were cut and studied after infiltration with a fluorescent low-viscous resin using confocal microscopy (CLSM). The image of the lesion was divided into two areas with different grey values. Lesion depths were calculated (ImageJ) from the surface to that point in the lesion where the grey value clearly changed to a darker grey value. The zone with the darker grey values marked the front of demineralisation. Mean lesion depths (+/- SD) after demineralisation were measured at 105 (+/- 21) microm. After single application, Resulcin [89 (+/- 22)%] and Helioseal [98 (+/- 6)%] had almost completely penetrated the lesion. Heliobond [126 (+/- 33)%] and Excite [184 (+/- 40)%] penetrated even deeper than the defined lesion. For Excite double application decreased the OIL significantly (p = 0.03; adjusted paired t-test). Adhesives are capable to penetrate artificial initial enamel lesions completely. Follow-up studies are needed to confirm this effect for natural lesions.

Acrylates↗

PubMed2004

A Confocal Laser Scanning Microscope investigation of different dental adhesives bonded to root canal dentine.

AIM: To evaluate the resin-dentine interface of different adhesive systems and corresponding luting cements proposed for bonding fibre posts to root canal dentine. METHODOLOGY: Fifty extracted maxillary canines and central incisors were used. After root canal treatment the teeth were randomly divided into five groups of 10 teeth each. Fibre posts were inserted with five different adhesive systems and corresponding luting cements. Group 1: Clearfil Core/New Bond (Kuraray), group 2: Multilink (Vivadent), group 3: Panavia 21/ED Primer (Kuraray), group 4: PermaFlo DC (Ultradent), and group 5: Variolink II/Excite DSC (Vivadent). The primer was labelled in each case with 0.1% Rhodamine B isothiocyanate (RITC). Each root was sectioned into 2 mm thick slices at 1, 4 and 7 mm below the cementoenamel junction. The resin-dentine interface was evaluated using a Confocal Laser Scanning Microscope; the thickness of the hybrid layer and the number of resin tags were measured. The statistical analysis was performed using nonparametrical tests for comparisons between groups; for overall comparisons the Kruskal-Wallis test was used. Intraindividual analysis within teeth was performed using a linear model. RESULTS: The thickness (microm) of the hybrid layer of group 1 (5.45; SD 1.21), group 4 (3.36; SD 1.59), and group 5 (4.33; SD 1.19) was significantly higher than in the other groups (P < or = 0.05). The number of resin tags observed in group 1 was significantly higher than in groups 2-4 (P < 0.05), but did not differ from group 5. Each group showed significantly more resin tags in the coronal and in the central part of the root canal than in the apical part (P < 0.001). CONCLUSION: Conditioning of the root canal dentine with phosphoric acid and the use of one- and two-bottle-bonding systems gave a thicker and more uniform hybrid layer with considerably more resin tags than observed after the use of 'self-etching' adhesives. This might provide a more durable bond of the post to root canal dentine.

Acid Etching, Dental↗

PubMed2004

Bristle end-rounding in toothbrushes: a comparison of different evaluation techniques, bristle position and viewing angle.

OBJECTIVE: Numerous studies using various evaluation techniques have shown substantial variations in the degree of bristle end-roundness of commercially available toothbrushes. The aim of the present study was to compare the effects of the examination angle, the bristle selection and two analyzing techniques assessing bristle end-rounding measurements. METHODOLOGY: The study was conducted in two parts. Part One used five randomly selected tufts from 20 brushes that were scanned with an electron micrograph (SEM; 45x) at two viewing angles (45 degrees and 90 degrees). Those bristle tips that were visible on both viewing angles were then judged by 1) a direct comparison to a grading scale, and 2) a shape factor (SF) analysis. In Part Two of the study, SEM images of five bristles from different tufts obtained from 40 brushes were taken at a viewing angle of 45 degrees, and five bristles from different locations within a tuft were also judged by both the direct comparison to a grading scale method, and the SF analysis, to assess bristle location. RESULTS: The SF values and the direct comparison percentage of rounded bristles did not differ because of the viewing angle (45 degrees or 90 degrees; p > 0.05; Mann-Whitney test), but differed significantly at various SF thresholds (percentage of bristles above or below a certain degree of end-roundness) when bristles from Part One were compared to Part Two (p < 0.01, adjusted chi-square-test). Location of the bristles from either the edge of a tuft or those located in the inner part had no effect on the assessments (p > 0.05). The results from the subjective direct comparison grading did not differ from those found with the SF analysis (p > 0.05). CONCLUSION: SF analysis is a time-consuming method for assessing bristle end-rounding, and can be as accurately done by direct comparison to a grading scale. One viewing angle (45 degrees) of bristles from different locations within a tuft can also be used to accurately assess a brush's level of end-roundness.

Analysis of Variance↗

PubMed2003

Apical leakage in maxillary type IV premolars with three different endodontic treatments.

The aim of this study was to evaluate the sealing ability in orthogradely filled, apicoectomised and retrogradely filled maxillary premolars with two canals and two separate apical foramina. The root canals of 51 extracted maxillary premolars of type IV were uniformly shaped and filled by means of lateral condensation and subsequently randomly divided into three groups of 17 teeth each. The teeth of groups II and III received an apicoectomy. In group III an additional retrograde seal (Ketac Fil) was applied. Group I served as control. All specimens were immersed in a methylene blue solution for 24 h. The teeth were cross-sectioned and the maximal dye-penetration was measured. The significantly least dye-penetration was observed in group II (apicoectomy only), followed by group I and group III. The differences among all groups were statistically significant (p<0.05). Most of the retrograde restorations in group III revealed circular colouration around the retrograde fillings extending to the gutta percha. Although the teeth of group II revealed the least dye-penetration, an apicoectomy cannot be favoured against an endodontic retreatment in maxillary premolars of type IV. The application of retrograde fillings using Ketac Fil must be considered critically.

Apicoectomy↗

PubMed2002

The effect of commercially available saliva substitutes on predemineralized bovine dentin in vitro.

OBJECTIVE: The objective of this study was to evaluate the effects of various saliva substitutes (Artisial; Glandosane; Oralube; Saliva medac; Oralbalance) on the lesion depth and the mineral content of predemineralized bovine dentin in vitro. MATERIALS AND METHODS: Ninety-six dentin samples were prepared from 24 freshly extracted bovine incisors. The samples were predemineralized (pH 5.5; 10 days), and subsequently exposed to the various artificial salivas. A carbonate-reduced mineral water (Hirschquelle) as well as the mouthwash solutions Meridol and biotène served as controls. Lesion depth and mineral loss were evaluated from microradiographs of thin sections (110 microm) by a dedicated software package (TMR 1.24). RESULTS: After storage in Glandosane and biotène, the results indicated a significant mineral loss and an increase in lesion depth (P < 0.01; Wilcoxon). In contrast, specimens stored in Oralube showed a decrease in lesion depth and an increase in mineral content (P < 0.05; Wilcoxon). CONCLUSIONS: Thus, the use of neither Glandosane nor biotène can be recommended in dentate patients with severe xerostomia.

Amines↗

PubMed2001

Effect of saliva substitutes on mineral content of demineralized and sound dental enamel.

The aim of this in vitro study was to evaluate the effects of commercially available saliva substitutes on the mineral content of pre-demineralized and sound enamel. From 56 bovine incisors 224 enamel specimens were prepared and hand-polished. The specimens were partially covered with nail varnish (control of sound enamel). In group 1, 112 samples were demineralized (18 days; 37 degrees C; pH 5.0) and a portion of the demineralized area was likewise covered with nail varnish. Subsequently, 16 specimens were exposed (14 days; 37 degrees C) to 10 ml of each of several different saliva substitutes (Artisial; Glandosane; Oralube; Saliva medac), or mouthwash solutions (Biotène; Meridol), respectively. Non-carbonated, fluoride-containing mineral water (Eptinger) was used as control. In group 2, the 112 sound enamel specimens were immersed directly in the solutions (without a demineralization period). After immersion, the specimens were cut perpendicular to the surface, and slabs (110 microns) were ground. Contact microradiographs were obtained and studied with a digital image-analyzing system. A dedicated software (TMR 1.24) was used to calculate the mineral content. Sound enamel (group 2) was significantly demineralized after immersion in Biotène and Glandosane (P < 0.001; Kruskal-Wallis). In group 1, mineral loss after storage in Biotène and Glandosane was significantly increased (P < 0.001), compared with the mineral content after demineralization. All other solutions revealed a significant mineral gain (P < 0.01; Wilcoxon), with the most pronounced effects after use of Oralube and mineral water (both containing calcium, phosphates, and fluorides). Therefore, administration of products similar to the last named can be recommended for dentate patients with salivary gland hypofunction.

Animals↗

PubMed2001

Tensile bond strengths of four different dentin adhesives on irradiated and non-irradiated human dentin in vitro.

This study evaluated the influence of irradiation on dentin bond strength. Sixty irradiated and 60 non-irradiated human third molars were used. The irradiation dose of 60 Gy was fractionally applied over 6 weeks (2 Gy day(-1), 5 days week(-1). All teeth were prepared in a special manner allowing the simulation of intra-pulpal pressure and dentin perfusion. Dentin specimens with a thickness of 2.0 mm were obtained under standardized conditions. The specimens were randomly assigned to four experimental groups. Tensile bond strength of four different dentin bonding agents (Scotchbond 1, Solobond Plus, Prime&Bond 2.1 and Syntac) was evaluated using an Instron Universal testing machine. Pairwise comparison did not show any significant differences between the irradiated and non-irradiated groups. The influence of the different dentin adhesives was significant (P=0.0001; ANOVA). Compared with Solobond Plus and Prime&Bond 2.1, the use of Scotchbond 1 resulted in a significantly higher tensile bond strength in non-irradiated specimen (P< 0.05; closed test procedure based on Kruskal-Wallis test). Within the limitations of an in vitro study, it can be concluded that adhesive restoration procedures can be successfully used in patients irradiated for cancer of the head and neck.

Adhesives↗

PubMed2001

[Effects of saliva substitutes and mouthwash solutions on dentin].

Saliva substitutes are used by patients suffering from hyposalivation to alleviate the symptoms of severe xerostomia. Therefore, the objective of this study was to evaluate the effects of various saliva substitutes (Artisial; Glandosane; Oralube; Saliva medac; Oralbalance) on the lesion depth and the mineral content in sound bovine dentin in vitro. 96 dentine specimens were prepared from 24 freshly extracted bovine incisors and exposed for seven days to the various solutions. A carbonate-reduced mineral water (Hirschquelle) as well as the mouthwash solutions Meridol and biotène served as controls. After storage in the solutions, the specimens were cut perpendicularly to their surfaces, polished up to 4000 grit and mounted on plexiglass microscope slides. The slabs were ground to a uniform thickness of 110 mu m. Lesion depths and mineral content were evaluated from microradiographs of the prepared specimens by a dedicated software (TMR 1.24) After storage in Glandosane and biotène results indicated a significant mineral loss and increase in lesion depth (p<0.01; Kruskal-Wallis). All other solutions used did not have any effect on the integrity of the dentin samples. Thus, the use of both Glandosane as well as biotène cannot be recommended in dentate patients with severe xerostomia.

Animals↗

PubMed2000

Effects of additional teaching of final-year dental students on their radiographic diagnosis of caries.

The aim of this study was to evaluate whether the skills of final-year dental students in the diagnostic interpretation of bitewing radiographs could be improved by additional didactic instruction. 6 consecutive classes of students in the same stage of education (last semester in the Department of Operative Dentistry) took part in the investigation from 1995 to 1998. At the beginning of each semester, the same in vivo made bitewing radiograph was demonstrated in a separate radiology revision lecture and interpreted with the students. The intensification of the training in the diagnosis of bitewing radiographs was made when the 4th class of students started. At the end of each semester, each student of the 6 consecutive classes was asked to evaluate the same bitewing radiograph, which had been demonstrated at the start of the semester. The students were not told that they had already diagnosed from this radiograph before. The results of the radiographic diagnosis were then analyzed using an evaluation system paying special attention to the treatment decision. True positive and true negative diagnoses were scored as correct and false positives and false negatives as incorrect. There was no significant difference (ANOVA) in the ability to diagnose from bitewing radiographs between the groups of students who received, and those who did not receive, additional training. The benefits of this type of additional instruction in the last semester in the Department of Operative Dentistry seem only to be important in some individual cases.

Analysis of Variance↗