Biomedical subjects

T Büyükyilmaz

Publications and source records attributed to T Büyükyilmaz.

10 recordsLinked to original sources

PubMed1998

The effect of 4% titanium tetrafluoride solution on root canal walls--a preliminary investigation.

The aim of the present study was to evaluate the effect of 4% titanium tetrafluoride (TiF4) solution on root canal walls by scanning electron microscopy. Twenty four root canals with or without a smear layer were treated with 4% TiF4 solution. Scanning electron microscopic observation of the smeared canal walls showed that TiF4 solution modified the smear layer and produced a massive structure. In smear-free group, a granular coating was formed on intertubular and intratubular dentin. The stability of this layer was tested further with EDTA and/or NaOCl irrigations on 20 additional specimens. It was observed that none of the solutions was able to remove this modified smear layer. These results may indicate that this extremely stable structure may be advantageous in endodontics, because it can prevent further infection of root canal dentin by sealing off the tubules permanently, and can reduce microleakage by preventing further dissolution and disintegration of the smear layer.

Cariostatic Agents↗

PubMed1998

Improved orthodontic bonding to silver amalgam. Part 2. Lathe-cut, admixed, and spherical amalgams with different intermediate resins.

Flat rectangular tabs (n = 270) prepared from spherical (Tytin), admixed (Dispersalloy) or lathe-cut amalgam (ANA 2000) were subjected to aluminum oxide sandblasting with either 50-mu or 90-mu abrasive powder. Mandibular incisor edgewise brackets were bonded to these tabs. An intermediate resin was used, either All-Bond 2 Primers A + B or a 4-META product--Amalgambond Plus (AP) or Reliance Metal Primer (RMP)--followed by Concise. All specimens were stored in water at 37 degrees C for 24 hours and thermocycled 1000 times from 5 degrees C to 55 degrees C and back before tensile bond strength testing. The bond strength of Concise to etched enamel of extracted, caries-free premolars was used as a control. Bond failure sites were classified using a modified adhesive remnant index (ARI) system. Results were expressed as mean bond strength with SD, and as a function relating the probability of bond failure to stress by means of Weibull analysis. Mean tensile bond strength in the experimental groups ranged from 2.9 to 11.0 MPa--significantly weaker than the control sample (16.0 MPa). Bond failure invariably occurred at the amalgam/adhesive interface. The strongest bonds were created to the spherical and lathe-cut amalgams (range 6.8 to 11.0 MPa). Bonds to the spherical amalgam were probably more reliable. The intermediate application of the 4-META resins AP and RMP generally created significantly stronger bonds to all three basic types of amalgam products than the bonds obtained with the All-Bond 2 primers. The effect of abrasive-particle size on bond strength to different amalgam surfaces was not usually significant (p > 0.05). The implications of these findings are discussed in relationship to clinical experience bonding orthodontic attachments to large amalgam restorations in posterior teeth.

Analysis of Variance↗

PubMed1997

The resistance of titanium tetrafluoride-treated human enamel to strong hydrochloric acid.

The acid resistance of TiF4-treated enamel was investigated to establish a possible treatment modality for endogenous dental erosion. Enamel slabs were prepared from human molars and treated with solutions of TiF4. Scanning electron microscopy (SEM) and microhardness testing were used to examine the effects of the exposure of the treated enamel to strong acid. SEM micrographs showed the presence of heavy deposits on enamel surfaces. The surface coating, formed following TiF4 application, appeared to be resistant to severe acid attacks. Microhardness measurements showed that TiF4 treatment inhibited enamel softening. It is concluded that topical TiF4 application may be effective in prevention of dental erosion caused by hydrochloric acid from the stomach in patients with frequent vomiting or gastroesophageal reflux.

Cariostatic Agents↗

PubMed1997

The caries-preventive effect of titanium tetrafluoride on root surfaces in situ as evaluated by microradiography and confocal laser scanning microscopy.

The aim of the present study was to investigate the cariostatic effect of titanium tetrafluoride (TiF4) on in situ-induced lesions on human root surfaces. Analysis of the samples was carried out by quantitative microradiography (TMR) and confocal laser scanning microscopy (CLSM). Pre-molar roots, sectioned into four pieces, were used for sample preparation. Before they were mounted into the recesses prepared in the acrylic intra-oral appliances, two root pieces from each tooth were treated with 4% TiF4 for 1 min, while the remaining two pieces served as controls. The appliances were worn by 12 volunteers for 4 wks. After 4 wks with no fluoride supplementation, the root pieces were removed and analyzed by TMR and CLSM. The TMR results showed that the TiF4 treatment reduced lesion depth and total mineral loss by 56% and 62%, respectively. CLSM images agreed well with the TMR measurements. A dense light-reflecting surface layer with almost intact subsurface structures was evident in the TiF4-treated samples.

Bicuspid↗

PubMed1997

Retention of titanium tetrafluoride (TiF4), used as fissure sealant on human deciduous molars.

When dental hard tissues are exposed to aqueous solutions of TiF4, an acid-resistant glaze forms on tooth surfaces. The aim of the present study was to examine the long-term retention of the glaze on TiF4-treated deciduous molars. The occlusal surfaces of four deciduous molars in each of seven children were treated with 4% TiF4 for 1 min. The sealed teeth were extracted after 1, 3, 6, or 12 months and examined with scanning electron microscopy. An extensive surface layer was present on all deciduous molars after 1 month. After 3 months the glaze appeared to be worn out on the cusp tips and in some areas on the cusp inclines. At 6 months the glaze was observed as small areas distributed over the cusp inclines with total coverage of the pits and fissures. After 1 year the presence of the glaze was limited to pits and fissures. Clinically, all fissures were caries-free by visual inspection at the end of the experimental period. The results indicate that the glaze formed after topical TiF4 application may be an effective way of sealing pits and fissures under clinical conditions.

Administration, Topical↗

PubMed1996

Surface preparation for orthodontic bonding to porcelain.

This study evaluated the effect of various porcelain surface treatments on the tensile strength of orthodontic brackets bonded to a feldspathic metal ceramic porcelain. The porcelain was fused to flat gold alloy tabs and divided into six groups that were subjected to sandblasting, silane application, intermediate resin, or etchants (9.6% hydrofluoric acid or 4% APF gels). Two brackets were bonded onto each porcelain/metal tab (n=60) with Bis-GMA resin (Concise, 3M Corp., St. Paul, Minn.) or 4-META resin (MCP-bond, Sun Medical Co. Ltd., Tokyo, Japan). The samples were stored in 37 degrees C water, thermocycled 1000 times from 5 degrees C to 55 degrees C and tested in tension. Alignment and uniform loading during testing were secured by engaging a hook in a circular ring soldered onto the bracket slot before bonding. Similar control brackets (n=12) were bonded with Concise to extracted caries-free mandibular incisors. Bond failure sites were classified according to a modified Adhesive Remnant Index (ARI) system. Silane application to the sandblasted porcelain surface significantly increased the bond strengths according to analysis of variance and Duncan's multiple range test. The quality of the bonds was further enhanced by the addition of the intermediate resin. Etching the porcelain with 9.6% hydrofluoric acid provided similar bond strengths, but the 4% APF gel was less effective. The MCP-bond was not significantly better than Concise in bond strength to sandblasted porcelain. Several difficulties associated with the clinical interpretation of laboratory data on bonding to dental porcelains are discussed, and clinical trials are necessary for final evidence of efficacy.

Acid Etching, Dental↗

PubMed1995

The effect on the tensile bond strength of orthodontic brackets of titanium tetrafluoride (TiF4) application after acid etching.

Titanium tetrafluoride (TiF4) was applied to acid-etched enamel surfaces to study the effect on surface structure and tensile bond strength of orthodontic brackets. Three groups of 20 premolars each were compared in debonding tests. Group I received a 1% and Group II received a 4% topical TiF4 treatment after acid etching. Group III served as control, that is, no fluoride solution was applied to the enamel after acid etching. Each treatment lasted 60 seconds followed by a thorough rinsing with water for 30 seconds. Brackets were bonded on all teeth with the same procedure. All premolars were then placed in a water bath at 37 degrees C. Ten teeth from each group were debonded after 24 hours, and the remaining teeth were debonded after 6 months. Results indicated that the application of 1% and 4% TiF4 solutions on etched enamel surfaces did not alter the tensile bond strength significantly after 24 hours and 6 months. The scanning electron microscope (SEM) examination of the surface structure demonstrated the presence of extensive reaction products, which covered enamel surfaces and appeared to interfere with etch patterns. It was concluded that the application of TiF4 solutions to etched enamel surfaces before bonding will not have an adverse effect on the tensile strength of orthodontic attachments.

Acid Etching, Dental↗

PubMed1995

Improving orthodontic bonding to gold alloy.

Flat tabs of cast gold alloy (n = 156) were subjected to either of three surface treatments: (1) roughening with diamond bur, (2) aluminum oxide sandblasting, and (3) sandblasting plus tin electroplating. Mandibular incisor edgewise brackets were bonded with Concise (BIS-GMA resin) (Unitek, Monrovia, Calif.) or Superbond C&B (4-META metal bonding resin) (Sun Medical Co. Ltd., Kyoto, Japan), or with Concise after application of an intermediate resin. All-Bond 2 Primers A and B (Bisco Dental Products, Itasca, Ill.), or B alone. All specimens were stored in water at 37 degrees C for 24 hours, and 60 were then thermocycled 1,000 times from 5 degrees C to 55 degrees C and back. The tensile bond strength testing was performed in a Lloyd 1,000R machine (Fareham, Hants, England). Alignment and uniform loading during testing were secured by engaging a hook in a circular ring soldered onto the bracket slot before bonding. Similar control brackets (n = 24) were bonded with Concise to extracted human premolars and lower incisors according to a routine procedure. Bond failure sites were classified by a modified ARI system. The results showed that sandblasting produced significantly stronger bonds to gold alloy than roughening with diamond bur. Superbond C&B provided significantly stronger bonds to gold alloy than Concise. There were generally insignificant differences in bond strengths between the water stored and the thermocycled specimens. Bond failures of Concise to sandblasted plus tin-plated gold alloy invariably occurred at the gold/adhesive interface, whereas those of Superbond C&B occurred within the adhesive or in the adhesive/bracket interface.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1995

Improving orthodontic bonding to silver amalgam.

Flat rectangular tabs (n = 84) prepared from lathe-cut amalgam (ANA 2000) were subjected to aluminum oxide sandblasting or roughening with a diamond bur. Mandibular incisor edgewise brackets were bonded to these tabs using: Concise (Bis-GMA resin); one of three metal-bonding adhesives, viz., Superbond C&B (4-META resin), Panavia Ex (10-MDP Bis-GMA resin) or Geristore (composite base); and Concise after application of the intermediate resins All-Bond 2 Primers A+B, or the Scotch-Bond Multi-Purpose (SBMP) system. All specimens were stored in water at 37 degrees C for 24 hours before tensile bond strength testing. Alignment and uniform loading during testing were secured by engaging a hook in a circular ring soldered onto the bracket slot before bonding. Similar control brackets (n = 12) were bonded with Concise to extracted caries-free mandibular incisors. Bond failure sites were classified by a modified ARI system. Mean tensile bond strengths in the experimental group ranged from 3.4 to 6.4 MPa--significantly weaker than the control sample (13.2 MPa). Bond failure generally occurred at the amalgam/adhesive interface. Superbond C&B created the strongest bonds to amalgam; according to ANOVA and Duncan's Multiple-Range test, they were significantly stronger than the bonds with Panavia Ex and Concise, with Geristore in between. However, the bond strength of Concise to sandblasted amalgam was comparable to the Superbond C&B bonds when coupled with an intermediate application of All-Bond 2 Primers A+B. The SBMP, on the other hand, was less effective.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum Oxide↗

PubMed1994

The effect of titanium tetrafluoride (TiF4) application around orthodontic brackets.

In the present in vivo study, the cariostatic potential of a titanium tetrafluoride (TiF4) solution applied topically around orthodontic brackets was investigated with quantitative microradiography. Also characteristics of the TiF4-treated enamel surface were examined with scanning electron microscopy (SEM). Ten pairs of premolars to be extracted for orthodontic treatment were used in the first part of this study. Brackets were bonded on all teeth with an orthodontic adhesive, and 10 randomly selected premolars served as controls, whereas a similar number were treated with 1% TiF4 around brackets for 60 seconds. After 4 weeks with no topical fluoride supplementation, all teeth were extracted and stored for analysis. Results indicated the 1% TIF4 solution reduced lesion depths and total mineral loss, at the bracket periphery, significantly during the 4-week period. The presence of a surface coating was demonstrated by SEM micrographs. It was concluded that TiF4 may provide a high level performance as a prophylactic agent for orthodontic purposes.

Child↗