2,2-Bis (2,3-hydroxypropoxy)phenylropane (bis-HPPP) is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...

that is formed when the

dental composite Dental composite resins (better referred to as "resin-based composites" or simply "filled resins") are dental cements made of synthetic resins. Synthetic resins evolved as restorative materials since they were insoluble, of good tooth-like appea ...

material

bis-GMA Bis-GMA (bisphenol A-glycidyl methacrylate) is a resin commonly used in dental composite, dental sealants. and dental cement. It is the diester derived from methacrylic acid and the bisphenol A diglycidyl ether. Bearing two polymerizable groups, ...

is degraded by

salivary The salivary glands in mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands (parotid, submandibular, and sublingual), as well as hundreds of minor salivary glands. Salivary glan ...

esterase An esterase is a hydrolase enzyme that splits esters into an acid and an alcohol in a chemical reaction with water called hydrolysis. A wide range of different esterases exist that differ in their substrate specificity, their protein structure ...

s. It is also called BADGE·2H₂O in reference to it being the hydrolysed form of

BADGE A badge is a device or accessory, often containing the insignia of an organization, which is presented or displayed to indicate some feat of service, a special accomplishment, a symbol of authority granted by taking an oath (e.g., police and fi ...

, which is used in the formation of epoxy resins. Structurally, it is a di-

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...

bisphenol A Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. It is a colourless solid which is soluble in most common organic solvents, but has very poor solubility in water. BPA is produced on an industrial s ...

Formation

Together with

methacrylic acid Methacrylic acid, abbreviated MAA, is an organic compound. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced indu ...

, bis-HPPP is released following the CE-catalyzed hydrolysis of 2,2- (2-hydroxy 3-methacryloxypropoxy)-phenylropane (bis-GMA). This reaction is very common in hydrolytic degradation of the dental resin since salivary esterases are able to cleave the ester bonds in

acrylic Acrylic may refer to: Chemicals and materials * Acrylic acid, the simplest acrylic compound * Acrylate polymer, a group of polymers (plastics) noted for transparency and elasticity * Acrylic resin, a group of related thermoplastic or thermosett ...

polymers of dental composites. Analysis by

mass spectrometry Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is use ...

demonstrated that

hydrolytic Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysi ...

reactions would cleave the

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...

bonds of both methacrylate units in bis-GMA and produce bis-HPPP along with two molecules of methacrylic acid.{{cite journal , author = Finer Y, S.J. , title = The influence of resin chemistry on a dental composite's biodegradation , journal = J Biomed Mater Res , year = 2004 , volume = 69A , pages = 233–246 , doi = 10.1002/jbm.a.30000 , pmid = 15057996 , last2 = Santerre , first2 = JP , issue = 2

References

Polyols Phenol ethers Glycerols 2,2-Bis(4-hydroxyphenyl)propanes