Faculty Profiles - KUBOKI Takuo

Limited interaction of a self-adhesive flowable composite with dentin/enamel characterized by TEM. International journal

Atsushi Mine, Jan De Munck, Annelies Van Ende, André Poitevin, Mariko Matsumoto, Yasuhiro Yoshida, Takuo Kuboki, Kirsten L Van Landuyt, Hirofumi Yatani, Bart Van Meerbeek

Dental materials : official publication of the Academy of Dental Materials 33 ( 2 ) 209 - 217 2017.2

Language：English Publisher：ELSEVIER SCI LTD

OBJECTIVES: A new category of composite which does not require any acid etching or bonding protocol prior to application has been introduced. The purpose of this study was to characterize the interfacial ultra-structure at enamel and dentin surfaces by means of transmission electron microscopy (TEM). METHODS: Non-carious human third molars were randomly divided into 6 groups (bur-cut dentin, SiC-ground dentin, fractured dentin, bur-cut enamel, SiC-ground enamel, and un-cut enamel). After preparation of the respective surfaces, the self-adhesive flowable composite (Vertise Flow, Kerr) was applied. Non-demineralized/demineralized and non-stained/stained sections of 70-90nm were prepared following common TEM-specimen processing procedures. Additional specimens were immersed in an ammoniacal silver nitrate solution. RESULTS: The composite-dentin interface was free of voids and no de-bonding occurred during specimen preparation. For bur-cut and SiC-ground dentin, no surface demineralization was observed and the smear contained residual hydroxyapatite. On fractured dentin (i.e. without smear interference), a very thin interaction area of 100-200nm without apparent signs of surface demineralization was seen. When the composite was bonded to enamel, a distinct separation between the self-adhesive composite and enamel was present in all three groups. A tight interaction, yet without distinct dissolution of hydroxyapatite, could only be seen in some regions at bur-cut enamel where smear was absent or sparse. Silver nitrate infiltration was associated with the presence of smear. SIGNIFICANCE: The self-adhesive composite showed limited interaction with smear-covered substrates and aprismatic enamel, which explains its inferior diminished bonding capacity in comparison with current adhesives.

DOI： 10.1016/j.dental.2016.11.010

Multicentered epidemiological study of factors associated with total bacterial count in the saliva of older people requiring nursing care.

Takashi Tohara, Takeshi Kikutani, Fumiyo Tamura, Mitsuyoshi Yoshida, Takuo Kuboki

Geriatrics & gerontology international 17 ( 2 ) 219 - 225 2017.2

Language：English Publisher：WILEY

AIM: To clarify whether the number of present teeth, independent of other well-known factors, was associated with the total bacterial count in the saliva of older people requiring care at nursing homes in a multicentered epidemiological survey. METHOD: The participants were 618 older people (mean age 86.8 ± 6.9 years; 122 men, 496 women) residing in 14 nursing homes across Japan. The dependent variable was the participant's salivary bacterial count, and the independent variables were basic demographic data, oral conditions and activity of daily living (measured by Barthel Index). Statistical analysis was first carried out by Student's t-test, Pearson's correlation coefficient analysis and Spearman's rank correlation coefficient analysis. Independent variables found to have a significant relationship to their salivary bacterial count by the univariate analyses were further examined by stepwise multivariate analysis. RESULTS: The independent variables shown by univariate analysis to have a significant positive relationship with higher salivary bacterial count were presence of food residue (P = 0.001), absence of mouth dryness (P = 0.001), need of oral care assistance (P = 0.001), inability to keep the mouth opened (P = 0.009), inability to gargle (P = 0.002), denture use (P = 0.004), higher number of present teeth (P = 0.006) and lower Barthel Index (P = 0.001). Subsequent multivariate analysis identified presence of food residue (P = 0.031), higher number of present teeth (P = 0.043) and lower Barthel Index (P = 0.001) as independent associated factors for higher salivary bacterial count. CONCLUSIONS: The present study found that presence of food residue, higher number of present teeth and decreased activity of daily living were significantly related to higher bacterial count in the saliva of older people requiring care. Geriatr Gerontol Int 2017; 17: 219-225.

DOI： 10.1111/ggi.12695

Reliability and validity of the patient disability-oriented diagnostic nomenclature system for prosthetic dentistry

Yoshizo Matsuka, Yoshiyuki Hagiwara, Katsushi Tamaki, Hisahiro Takeuchi, Masanori Fujisawa, Takahiro Ono, Yoshihiro Tsukiyama, Kan Nagao, Kazuhiro Tsuga, Hideki Aita, Hisatomo Kondo, Kenji Fueki, Hiroaki Tsukasaki, Keisuke Nishigawa, Shogo Ozawa, Rika Kuwatsuru, Hajime Minakuchi, Toshimitsu Iinuma, Takashi Matsuura, Kanji Ishibashi, Shigehisa Fujii, Toshihiro Hirai, Keiichi Sasaki, Hirofumi Yatani, Yoshimasa Igarashi, Yuji Sato, Tetsuo Ichikawa, Tetsuo Yamamori, Takuo Kuboki, Kazuyoshi Baba, Kiyoshi Koyano, Hironobu Sato, Hideo Matsumura

JOURNAL OF PROSTHODONTIC RESEARCH 61 ( 1 ) 20 - 33 2017.1

Language：English Publisher：ELSEVIER IRELAND LTD

Purpose: The Japan Prosthodontic Society (JPS) has proposed a new diagnostic nomenclature system (DNS), based on pathogenesis and etiology, to facilitate and improve prosthodontic treatment. This systemspecifies patient disability and the causative factor (i.e. "B (disability) caused by A (causative factor)''). The purpose of this study was to examine the reliability and validity of this DNS.
Study selection: The JPS Clinical Guideline Committee assessed mock patient charts and formulated disease names using the new DNS. Fifty validators, comprising prosthodontic specialists and dental residents, made diagnoses using the same patient charts. Reliability was evaluated as the consistency of the disease names among the validators, and validity was evaluated using the concordance rate of the disease names with the reference disease names.
Results: Krippendorff's a was 0.378 among all validators, 0.370 among prosthodontic specialists, and 0.401 among dental hospital residents. Krippendorff's alpha for 10 validators (3 specialists and 7 residents) with higher concordance rates was 0.524. Two validators (1 specialist and 1 resident) with the highest concordance rates had a Krippendorff's alpha of 0.648. Common disease names had higher concordance rates, while uncommon disease names showed lower concordance rates. These rates did not show correlation with clinical experience of the validator or time taken to devise the disease name.
Conclusions: High reliability was not found among all validators; however, validators with higher concordance rates showed better reliability. Furthermore, common disease names had higher concordance rates. These findings indicate that the new DNS for prosthodontic dentistry exhibits clinically acceptable reliability and validity. (C) 2016 The Authors. Published by Elsevier Ltd on behalf of Japan Prosthodontic Society. This is an open access article under the CC BY-NC-ND license.

DOI： 10.1016/j.jpor.2016.06.005