Method of making shaped dental articles via photoiniferter polymerization of the dental compositions

A method of making a dental article comprising the steps of:

• (i) forming a mixture of
• (a) acrylic photoiniferter block polymer selected from the group consisting of I(BT).sub.n, I(BAT).sub.n, and mixtures thereof, wherein
• I represents the free radical initiator portion of an iniferter of the formula I(T).sub.n ;
• T represents the terminator portion of said iniferter;
• n is an integer of at least 1, wherein I(T).sub.n is capable upon being subjected to a radiant energy source of forming free radicals I(.multidot.).sub.n and nT.multidot., wherein I.multidot. is a highly reactive free radical capable of initiating free radical polymerization and T.multidot. is a less reactive free radical which is generally much less capable of initiating free radical polymerization than I.multidot. but will rejoin with I(.multidot.).sub.n or a free radical polymer segment free radically polymerized with I(.multidot.).sub.n upon termination of said radiant energy source;
• B represents an acrylic polymer block having a glass transition temperature of about -200.degree. C. to about 400.degree. C. and a molecular weight of about 1,000 to about 50,000;
• and
• A represents a thermoplastic polymer block having a glass transition temperature ranging from about 30.degree. C. to about 150.degree. C.;
• and further wherein the glass transition temperature of block A is at least about 50.degree. C. higher than that of block B;
• (b) a monomer charge comprising free radically polymerizable monomer of the formula C(D).sub.x, wherein
• x is an integer ranging from 1 to about 9,
• D is an acrylate or methacrylate moiety, and
• C is an alkyl, aryl, or aralkyl organic residue, and
• (c) about 5 to about 90 weight % of a filler based upon the weight of said mixture,
• wherein the weight ratio of the acrylic photoiniferter block polymer to free radically polymerizable monomer of the formula C(D).sub.x ranges from about 1:99 to a about 99:1;
• (ii) exposing the mixture to radiation of about 200 to about 800 nm from a radiant energy source until polymerization or crosslinking of the acrylic photoiniferter block polymer and free radically polymerizable monomer occurs in order to form a partially cured dental article;
• (iii) shaping the partially cured dental article of step (ii) as desired;
• (iv) repeating steps (ii) and (iii), if necessary, until the desired shape of the partially cured dental article has been obtained;
• and
• (v) exposing the partially cured dental article of either step (iii) or step (iv) to a final exposure of radiation in order to form a final cured dental article.