Figure 1: Pre and postoperative bite-wing and periapical radiographs of a pulpotomy procedure, following which a stainless-steel crown and band and loop were placed on tooth #85. Notice the extent of the cameral filling that reaches into the entrance of the root canals.
instead of 1.5 mm for permanent teeth and dentin thickness between the pulp chamber and the enamel layer is less than in permanent teeth.
The pulp of primary teeth possesses the ability to form a dentin-like matrix (tertiary dentin) as part of the repair mechanism of the dentin-pulp complex. In that context, vital pulp therapy procedures (or indirect capping) aim to treat reversible pulpal injury due to caries, restorative procedures, or trauma.3 It is considered nowadays an acceptable procedure at the express condition that the diagnosis is based on good history and proper clinical and radiographic examination, and most important, that the tooth is properly sealed with a leak-resistant restoration.4 On the other hand, direct pulp treatment procedures are less predictable as failure is likely to occur even in the case of a pinpoint pulp exposure free from oral contaminants and that occur under rubber dam isolation.5 Such teeth should generally be treated using alternate and less alternative procedures such as pulpotomy or pulpectomy.
Pulpotomy According to the American Academy of Pediatric Dentistry, pulpotomy is the ablation of infected or affected pulp tissues leaving the residual vital pulp tissues intact, thus preserving vitality and function (totally or partially) of the radicular pulp6, and the remaining pulp stump is covered with a capping agent. The only difference between pulp capping and vital pulpotomy resides in the quantity of pulp tissue that is removed. In case of vital pulpotomy on permanent teeth, an agent allowing the cauterization of the amputated site is used such as calcium hydroxide. However, the success of this technique as previously stated is rather low and is conditioned by 3 parameters: the tooth must be in stage 1 (roots still in formation), the trauma
relative to the operatory procedure must be minimal, and a high-pH calcium hydroxide must be used. If primary teeth are in stage 2 or later, non-vital pulpotomy should be performed, and the residual stump covered by a pharmaceutical fixative agent such as formocresol. The success of either treatment is measured by the absence of clinical symptoms such as pain or edema, the absence of radiologic symptoms such as internal resorption or intracanal calcifications, the absence of periodontal involvement, and finally the preservation of the integrity of the definitive germ or permanent bud.7
Theoretically, following access opening and total cameral roof removal, the tissue in the pulp chamber must be completely excised all the way to the pulp stumps or opening of the “infandibulum” (Figure 1). In fact, the level to which the pulpotomy is performed is adjusted according to the clinical judgment of the operator7 since all inflammation has to be removed to allow placement of the medication on sound pulp tissues. Several studies have shown that when pulp exposure is traumatic (fracture) or iatrogenic (following cavity preparation), the inflammation is confined to the superficial layer (1-2mm) without bacterial infiltration, and this even in case of prolonged
salivary exposure (168h).8-10
When carious lesions are
extensive and allowing direct bacterial contact with the pulp, inflammation is present between 1 and 9mm from the surface with abscess and pus formation.8,10
Many agents were used in pulpotomy procedures and formocresol was by far the most popular due to its ease of use and excellent clinical results, although longitudinal studies have reported that the clinical success of formocresol pulpotomies decreased with time and that histologic response of the pulp was variable ranging from chronic inflammation to necrosis.11 From another
INTERNATIONAL DENTISTRY SA VOL. 11, NO. 2