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SIsSlReDort

Pulp-dentin biology in restorative dentistry. Part 1: Normal structure and physiology
Ivar A, Mjor, BDS, MSD, MS, DrodontVOdd B, Sveen. LDS, MS, Karin J, Heyeraas, Cand Med Dent,
Considerable knowledge has accumulated over the years on the structure and function of the dental pulp and dentin. Some of this knowledge has important clinical implications. This review, which is thefirst ol seven articies, will be limited to those parts ot the normal structure and physiology of the puip and dentin that have been shown to result in, or are likely lead to, tissue reactions associated with the clinical treatment ot these tissues. Although certain normal structures will be highlighted in some detail, a basic knowledge ot pulpal and dentinal development and structure is aprerequisite tor an understanding of this text, (Quintessence tnt 2001:32:427-448) Key words; dentin, dentinal tubule, odontoblast, pulp, tooth structure

n countties where endodontics has been identified as a specialty, and especially where it has been administratively separated from teacfiing programs in restorative and conservative dentistry, there has been a tendency to classify studies of dentin andpulp as "endodontics," In diagnosing pain and attempting to clinically predict the physiologic or pathologic state of the dentin and pulp, endodontists depend on a thorough knowledge of the tissues. However, this diagnostic responsibility also extends to restorative dentistry, including operative and conservative dentistry, Tbe treatment pbase of restorative dentistry is, or should be, moreinvolved tban endodontics witb tbe structure, function, tissue reactions, and potential bealing capacities of dentin and pulp. All caries propbylactic measures and treatment phases of restorative dentistry sbould be considered "preventive endodontics," To optimally acbieve tbis goal, clinicians working witb dentin and pulp must bave detailed knowledge of normal tootb structure; age-related cbanges;tissue responses to caries, trauma, and restorative procedures; and tbe effect of tbe application of different agents and materials on tbe tissues. Knowledge of tbe biology of the pulp and dentin, coupled witb an understanding of the materials and techniques applied to tissues, will provide a sound basis for restorative dentistry, Sucb
'Professor AcaOemy 100 Eminenl Scholar, Departmenl of OperativeDentistry, University ol Florida, College of Dentistry, Gamesvilie, Fiorida; NIOM, Scandinavian Institute of Dental Materiais, Hasium, Norway. ^Associate Prolessor, Eastman Department of Oentistry, University of Rocfiesler, Scfiool of Medicine and Dentistry, Rochester, New York, ^Professor, Department of Physiology, University of Bergen, Faculty of Medicine, Bergen, Non^ay. Reprint requests: Drivar A. Mpr, NiOM, Kirkeveien 71B, PO BOX 70, Hasljm, N-1305 Norway. E-maii: imior@niom.no or imior@dentai,Ljfi,eiiu,

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knowledge will make it possible for tbe dentist to select materials and methods tbat will produce no or favorable reactions in the tissues to optimally conserve damaged teeth. It should also provide opportunities for new hiologic approaches to restorative dentistry.STRUCTURE OF THE PULP-DENTIN ORGAN

Despite tbe differences in structure and composition, pulp and dentin are integrally connected in tbe sense that pbysiologic and patbologic reactions in one of the tissues will also affect tbe otber. This close association includes reactions to caries and common clinical procedures sucb as cavity or crown preparations and restorative procedures. Not only do tbe twotissues bave a common embryonic origin, but tbey also remain in an intimate relationsbip tbrougbout tbe life of the vital tootb, Anytbing tbat affects dentin will affect tbe pulp and vice versa, Tbe concept of a pulp-dentin organ or a pulp-dentin complex is, tberefore, wellfounded and generally recognized. However, tbe concept has been challenged by reference to the marked differences in...