Study Conducted in the Department of Oral Biology and Pathology at Stony Brook University School of Dental Medicine
BasicBites and their inhibition of hydraulic conductance of dentine in treating tooth sensitivity
Dentinal hypersensitivity is a common problem among adults, which manifests as sharp pain in exposed dentin of a tooth or teeth upon exposure to thermal, evaporative, tactile, osmotic or chemical stimuli.1 Hypersensitivity occurs when there is clinical exposure of dentinal tubules of a tooth or teeth, when tooth dentin loses its covering protective enamel by traumatic tooth brushing, acid dissolution of dental root surface cementum and dentine after acid or physical exposure following gingival recession.2,3 Although the mechanism of pain transmission across dentin is not fully understood, both dentin permeability and tooth hypersensitivity are increased, when dentinal tubules are opened up.4
Hence, hypersensitivity treatment strategies have mainly focused upon tubular occlusion.3 Desensitizing products may be in the form of topically applied agents such as resins, varnishes, primers, dentin bonding agents, composite restorations or application of calcium phosphate containing compositions.5-7 In our laboratory, we have tested a dentinal tubular occluding compound in the form of a confection containing the occluding active composition, arginine bicarbonate/calcium carbonate. In the instant experimental demonstration, the same compound is the active ingredient in a softened confection called “BasicBites” (Ortek Therapeutics, Roslyn Heights, N.Y.) which has been applied in a dentinal tubular plugging simulator device, to determine whether it could upon softening and tooth application by chewing or finger application reduce the hydraulic conductance of a dentin disc and thereby test for reduction in dentinal sensitivity by such means clinically.
Materials and Methods
Dentin disc preparation: Extracted sound human molar teeth without any restorations were sliced horizontally to produce tooth slices for dentinal hypersensitivity testing. Slicing was done with a water-cooled low speed saw using an 0.15mm thick diamond blade (IsoMet, Buehler, Lake Bluff, IL). Mid-coronal dentin discs with a thickness of 635µm were thereby obtained. Such a disc (i.e. dentinal disc) was then etched with 10 ml of 50% citric acid for 15 minutes with constant shaking to remove the micro-crystalline debris occluding and thereby opening its dental tubular orifices. Dentinal discs were then removed from the acid and rinsed thoroughly in deionized water. Such a disc was then placed in the plastic hydraulic chamber of the device shown in Fig. 1.
Application of BasicBites and hydraulic conductance determination: Approximately 2.0 g of BasicBites confection was transformed into a softer consistency by mixing with 1740 g centrifuged whole saliva supernatant donated by a human subject. The resulting mixture was applied manually by fingertip application to the exposed surface of the dentine disc positioned in the device chamber. Fluid flow was recorded every 5 minutes for successive 30 minute intervals, before and 90 minutes after a BasicBites application to a tooth. The volume of fluid flowing through the dentin disc in 5 minutes was determined by multiplying the number of millimeters that an indicator bubble in the apparatus has traveled by 0.5 µl. (A 100 mm long capillary tube contains 50 µl of fluid and hence one mm displaces 0.5µl of fluid).
Hydraulic conductance values were then calculated as µl/ PTA, µl of fluid flow, where P = Hydrostatic pressure, T = Time of fluid flow and A = 0.32cm2 exposed surface area.
The hydraulic conductance values obtained, expressed in percentages, are presented in Fig.1. The % hydraulic conductance value without the application of BasicBites paste rose from 75% to 100% in a period of 30 minutes after applying BasicBites. This immediately dropped to an average value of 22% in a period of 90 minutes. The results of a second dentin disc treated with BasicBites, more or less showed the same pattern of reduction in hydraulic conduction after the application of BasicBites paste (see Fig.2).
According to the hydrodynamic theory for tooth sensitivity, dentinal hypersensitivity is related to the movement of inter-tubular fluid through the apparatus. The results of this evaluation demonstrated BasicBites ability to block dentinal tubules. The arginine bicarbonate/calcium carbonate entity reduced the mobility of tubular fluid by 76 to 78%, by occluding the orifices of the dentinal tubules, an event observed with a single application of BasicBites. Accordingly, repeated use of BasicBites confection identifies a new treatment modality of dentin hypersensitivity.
Dowell P, Addy M. Dentin hypersensitivity-A review. Aetiology, symtoms and theories of pain production. J Clin. Periodontol. 1983; 10: 341-350.
Addy M, Pearce N,. Aetiological, predisposing and environmental factors in dentin hypersensitivity. Arch. Oral Biol. 1994; 39 Suppl; 33S-38S.
Porto IC, Andrade AK, Montes MA. Diagnosis and treatment of dentinal hypersensitivity. J oral Sci. 2009; 51: 323-332.
Imai y, Akimoto T. New method of treatment of dentin hypersensitivity by precipitation of calcium phosphate in situ. Dent Mater J 1990; 9: 167-172.
Cherng AM, Takagi S, Chow L. Reduction in dentin permeability using a slurry containing dicalcium phosphate and calcium hydroxide. J Biomed Mater Res B Appl Biomater. 2006; 78: 291-295.
Komabayashi T, Imai Y, Ahn C, Chow LC, Takagi S. Dentin permeability reduction by a sequential application of calcium and fluoride-phosphate solution. J Dent. 2010; 38: 736-741.
Guentsch A, Seidler K, Nietzsche S, Heft AF, Preshaw PM, Watts DC, Jandt k, Sigusch BW. Biometric mineralization: Long-term observation in patients with dentin sensitivity. Dent Mater. 2012; 28: 457-464.
J. D. Greenhill and D. H. Pashley: The effects of desensitizing agents on the hydraulic conductance of human dentin in vitro. J Dent Res; 60(3): 686-698, 1981.