Monkey pulpal response to an MMA-based resin cement as adhesive luting for indirect restorations.
OBJECTIVE
The objective of this study was to evaluate the pulpal response to a newly-developed MMA resin cement (MultiBond, Tokuyama) when used for adhesively luting composite resin inlays.


METHODS
Cervical cavities were prepared in monkey teeth. The teeth were randomly divided into 3 groups. In the experimental group, a self-etching primer and a resin cement were applied to the cavities, and then hybrid composite inlays (Estenia, Kuraray) were inserted using freshly mixed resin cement. In the other groups, a zinc oxide/eugenol cement (Eugedain, Showa Yakuhin Kakou) or a glass-ionomer cement (Fuji II, GC) was used to fill the cavity. The teeth were then extracted after 3, 30, and 90 days, fixed in 10% buffered formalin solution, and prepared using routine histological techniques. Five-mum-thick sections were stained with hematoxylin and eosin, or Brown & Brenn gram stain for bacterial observation. Histopathological reactions in the pulp tissue and bacterial penetration along the cavity walls were assessed using a standardized score.


RESULTS
No serious inflammatory reactions in the pulp, such as necrosis or abscess formation, were observed in any of the experimental periods, except for 1 case after 30 days, in which a pulpal exposure was suspected. Disarrangement of the odontoblast layer and deposition of reparative dentin were the major reactions observed in this specimen. No bacterial penetration along the cavity walls was detected. The monkey pulpal response and in vivo sealing ability of the MMA resin cement in combination with the self-etching primer was considered as good as that of the glass-ionomer cement.


CONCLUSIONS
The new MMA resin cement showed acceptable biological compatibility to the monkey pulp when used to adhesively lute composite resin inlays.
Shimada
Yasushi
Y
Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan. shimada.ope@tmd.ac.jp
Seki
Yuichi
Y
Uzzaman
Mohammed Akhtar
MA
Sattabanasuk
Vanthana
V
Sasafuchi
Yasutaka
Y
Foxton
Richard M
RM
Otsuki
Masayuki
M
Tagami
Junji
J
D000180:Acrylic Resins; D000818:Animals; D003188:Composite Resins; D003738:Dental Cements / Q000494:pharmacology*; D003782:Dental Pulp / Q000187:drug effects*; D005899:Glass Ionomer Cements / Q000494:pharmacology; D000882:Haplorhini; D008768:Methylmethacrylates / Q000494:pharmacology*; D011140:Polyurethanes; D015035:Zinc Oxide-Eugenol Cement / Q000494:pharmacology
D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D003738:Dental Cements; D005899:Glass Ionomer Cements; D008768:Methylmethacrylates; C482145:Multibond; D011140:Polyurethanes; D015035:Zinc Oxide-Eugenol Cement; C060877:Dakril 4B