Pédiatrie

Zinc oxide-eugenol pulpotomy and stainless steel crown restoration of a primary molar Theodore P, Croll* / Constance M. Killian* *

The most dtirable and reliable method of retaining a primary molar in the motith after a pulpotomy procedure is complete-coverage restoration with a preformed stainless steel crown. This paper describes a method for performing pitlpotomy and stainless steel crown restoration of a primary molar. Neither formocresol, ghiteraldehyde, nor hydroxide is tised during the pulpotomy phase of the treatment. (Quintessence Int 1992:23:383-388.)

Introduction sions or malformed or severely traumatized primary canines and molars if preformed stainless steel crowns Informal surveys of general dentists reveal that many were not availahle. who treat children seldom use stainless steel crowns While the debate continues over the hest type of for primary molars. Some dentists do not even have intrapulpal space medication for use during pulp- preformed stainless steel crown kits in their office sup- otomy procedures for primary teeth, a surprisingly ply inventory. When dentists are queried as to why simple method of pulpotomy has received httle atten- they are reltictant to use stainless steel crowns, the tion. However, the method has proved most valuable usual response is that the dental school experience in and reliable in clinical use over the past 20 years. pédiatrie dentistry casts a negative light on such "ad- This paper documents a step-hy-step procedure for vanced" concepts as stainless steel crowns. Pédiatrie restoration of a pulpally involved primary first molar dentists, especially those in nonQuoridated areas or using a thick paste of -eugenol alone as the other regions with a high prevalence of caries, would pulpal space obturation material. The pulpotomy is be severely hampered in treating eotnplex carious le- followed hy immediate placement of a custom- adapted, preformed stainless steel crown.

Technique

* Private Practice, Pédiatrie Dentistry, Doyiestown, Pennsyl- The zinc oxide-eugcnol pulpotomy and stainless steel vania; Clinica) Associate Professor, Department of Pcdiatric crown procedure is performed as shown in Figs 1 to 17. Dentistry, University of Pennsylvania, School of Dental Medieine; Adjunct Professor, Department of Pédiatrie Dentis- try, University of Texas, Healtb Science Center at Houston {Dental Branch), Discussion ** Private Practice, Pédiatrie Dentistry; Doyiestown, Pennsyl- vania; Clinical Assistant Professor, Department of Pédiatrie Prospective success of a pulpotomy begins during the Dentistry, University ol Pennsylvania, School of Dental treatment-planning phase of the procedure. If careful Medicine, criteria are used to evaluate the tooth for which pulp- Address all correspondence toDrT, P. Croll, Georgetown Commons. Suite 2, 708 Shady Retreat Road, Doylestowu, Pennsylvania otomy is planned, the prognosis for long-term success 18W1, is better.

Quinlessence International Volume 23, Number 6/1992 383 Pédiatrie Dentistry

Fig 1 Primary first moiar with severe carious destruction. Fig 2 A iarge, inuerted-cone. water-cooled carbide bur After appropriate loeai is administered, rubber rapidly reduces the occiusal surface by 2 to 3 mm. dam is placed.

Fig 3 A sterile, water-cooled carbide bur is used to re- Fig 4 A steriie cotton pellet is compressed into the pulp move caries and enter the pulp cbamber. A sterile, siow- chamber and retained until residuai hemorrhage of radicu- speed round bur débrides aii pulpai tissue from the lar pulpal tissue has ceased. chamber to the level of the root canai openings.

Fig 5 iHemostasis is achieved, and the pulp chamber is Fig 6 A thick mix of pure zinc oxide-eugenoi cement is ready for placement of fhe restorative material. compressed gently into the chamber and permitted to hard- en. Reinforced zinc oxide-eugenol paste is not used.

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Fig 7 Axial coronal preparation is performed with a water- Fig 8 After the tooth has been reduced axially, maintaining coded, coarse diamond bur. The wooden wedge protects tooth form in miniature, axio-occlusal line angles are interproximal gingivai tissue. rounded.

Fig 9 The finished preparation is shown from the occlusal Fig 10 (mirror view) A crown with oimensions that wiii repli- view. Note the mesial and distai spacing and the axiai scal- cate the original coronai form in aii spatial reiationships is loping to increase cement-tooth structure interface. selected. Contacts are reestabiished, and original marginal ridge heights are duplicated.

Fig 11 A spoon excavator or cleoid-discoid is used to Fig 12 A heatless stone is used to establish correct coronal remove the crown form after try-in. Note the mesial décal- length. Crown-cutting scissors are much less precise for cification lesion on the adjacent second molar. That lesion marginal cutting. wili be trimmed smooth and the surface treated with topical fluoride solution.

Quintessence International Volume 23, Number 6/1992 385 Pédiatrie Dentistry

Fig 13 Flat-edged crimping pliers are used to crimp tbe Fig 14 A customized croviin form, ready for cementation, edge of tbe margin so tbat the finisbed margin can engage is compared to the preformed crown as suppiied by the the undercut of ttie cervical buige. manufacturer.

Fig 15 After a creamy mixture of polycarboxylate cement Fig 16 Excess cement is removed with sharp band instru- is pieced within the crown carefully, to avoid trapping air, ments, such as a sealer or a cleoId-discoid, or an ultrasonic the crown is seated with firm pressure appiied with a mirror scaier. Excess proximal cement can be dislodged with handle. Glass-ionomer luting cement can also be used. knotted dental tape.

Fig 17 The finished crown.

386 Quintessence International Volume 23, Number 6/1992 Pédiatrie Dentistry

Fig ISa Another primary first molar is shown 7 years afler Fig 18b The pulpotomy and crown are shown radiographic- zinc oxide-eugenoi pulpotomy and piacement of a stain- aiiy (left) 4 years after treatment and (right) 7 years post- less steel crown. operative i y.

Contraindications for vital pulpotomy in a primary dehyde, pure ealcium hydroxide has been used as a molar include history of spontaneous pain; sensitivity pulpotomy medication. Too often, however, rapid to perctission; mobility of the tooth: presence of sinus internal resorplion of the root and crown results,'"" tract, indicating dcntoalveolar abcess; and radiographie so that method is not recommended. evidence of pathosis. Any of these signs or symptoms The concept of nonaldehyde pulpal therapy for indicate that the inflammatory process has progressed primary teeth has recently been described. Yacobi et beyond the confines of the involved tooth into adja- al'* reported a technique for pulpectomy that uses cent tissues. Likelihood for a successful pulpotomy in only zinc oxide-eugenol paste.''' At 12 months, their such cases is poor. rate of success was the same as that reported for During preparation of the tooth, rubber dam is used formocresol pulpotomy. Over the past decade, we to isolate the tooth from surrounding soft tissues and have performed zinc oxide-eugenoi pulpotomies for saliva. Exposed pulpal tissues are therefore protected primary molars without using any other agent and from salivary contamination. have had similar chnical results. In light of concerns Use of formocrewl as a pulpal tissue fixative is con- regarding safety of aldehyde compounds, zinc oxide- troversial.'~' Both in vitro and in vivo studies have dem- eugenol pulpotomy should be considered as an alter- onstrated that form ocre so I placed in contact with native to formocresol or gluteraldehyde pulpotomies vital pulpal tissue is distributed systemically.'"^ For- for treatment of certain primary molars. mocresol with '""C-labeled has been A stainless steel crown is Ihe restoration of choice used in pulpotomies and subsequently recovered in for a tooth that has undergone pulpotomy. Ideally, the , kidney, heart, spleen, and lung tissue of treated crown should be placed immediately after pulpotomy animals.^ to eliminate the need for placement of an interim GI Uteraldehyde has been studied as an alternative restoration. An interim restoration is prone to marginal to formocresol for pulpal fixation.''"' However, breakdown, and the weakened tooth to fracture. gluteraldehyde placed in contact with pulpal tissue is Complete coverage with a preformed stainless Steel also distributed systemicalJy.^ In addition, a clinical crown strengthens the weakened crown and protects sludy of gluteraldehyde pulpotomies did not report against leakage at margins of the pulpal space res- a success rate equal to that demonstrated by formo- toration. cresol.'" Further studies of the effect of concentration Once the appro pria te-si zed stainless steel crown has and exposure time of gluteraldehyde on pulpal tissue been selected, it is important that the margins of the have been recommended to ascertain clinical usefulness crown be well adapted to the anatomic form of the of gluteraldehyde." prepared tooth. Myers" has shown that rough crown In an effort to avoid formocresol and gluteral- margins enhance plaque accumulation, frequently

Quintessence International Volume 23, Number 6/1992 387 Pédiatrie Dentistry

resulting in gingival inflammation. Although Ion Ni- Chro crown.s (3M Dental Products Div) closely resem- bie the anatomic form of primary molars, proper trimming, contouring, and finishing are essential to en- sure proper fit. Martens and Dermaut'" demonstrated that the results of trimming crown margins with an ahrasive wheel are superior to those achieved with crown and bridge scissors. Similarly, use of a rubber wheel for polishing results in a smoother crown margin that is less likely to accommodate plaque aceuniulation, Tripoli and jeweler's rouge, applied by rag wheel on a lathe, can be used to attain an especially fine surface polish. 1st Greater International References Bulgarian 1, Judd PL, Kenny DL: Formocresol concerns: a review, J Can Dtiif Aiw 1987:53:401-405, Dental Congress 2, Myers DR, et al: The acute toxicity of ¡ligh doses of systcm- ically administered formotresol in dogs, Pediatr Dem 1981;3:37-41, 2nd Annual Meeting 3, Beali JR, Ulsamer AG: Formaldehyde and hcpatotoxitity: a review, J Toxicot Environ Health 1984:13:1-21, of Bulgarian Dentists 4, Rolling I, Thulin H: tests against formaldehyde, cre- sol, and eugenol in children with pulpotomized primarj 2nd Greater Bulgarian teetb, Scand J Dem Res 1976:84:345-347. .•;, MyersDR. Shoaf HK, DirksenTK, et al: Distribution of 14C Dental Exhibition formaldehyde after pulpotomy with formocresol, J Am Dent Assoc 1978:96:805-813, 6, Ranly DM: Assessment of the systemic distribution and toxic- ity of formaldehyde following pulpotiimy treatment, 1. J Deni Child 1985;52:431^34, 7, Ranly DM, Hom D: Assessment of the systemic distribution October 15-17, 1992, and toxicity of formaldehyde following pulpotomy treatment, [|, / Dem Child 1987;.S4:40-44, Plovdiv 5, Paîhley EL, et al: Systemic distribution of I4C formaldehyde from formocresol-trcated pulpotomy sites, J Dem Res 198O;59:602-607, 9, Myers DR. Pasbley DH, Lake FT, et al: Systemic absorption of 14C-gluteraldehyde from glutcraldcbyde-trcated pulp- otomy iiteb. Pediatr Deni 1986;8:134-138, 10, Fuks AB, Bimstein E. Guelman M. et al: Assessment of j 2 percent buffered gluteraldehyde solution in pulpotomized pri- mary teeth of school children. J Dem Child lW0;57:371-375, 11, Sun HW, Feigal RJ, Messer HH: Cytotoxicity of gluteral- dehyde and formaldehyde in relation to time of exposure and COUPON concentration, Pediair Dem W90; 12:303-307, I am interested in the 1st Greater International Bulgarian 12, Via W: Evaluation of deciduous molars treated by pulpotomy Dental Congress, Please send funher details to: and calcium hydroxide, J Am Dent Assoc 1955:50:34—43, 13, Spedding RH, Mitchell DH, McDonald R: Formoeresol and calcium hydroxide therapy,,/ Dent Res 1965:44:1023-1034, 14, Yacobi R, Kenny DJ, Judd PL, et al: Evolving primary pnip therapy techniques, 7/l;fi Deni Assoc l99];122:83-85, 15, Myers DR: A clinical study of tbe response of the gingival tis- sue surrounding stainless steel crowns, / Deni Child 1975:42:281-284, 16, Martens LC, DermauL LR: The marginal polishing of Ion Ni- Chro crowns: a preliminary report. J Dent Child 1983,5(1:417-421, D Mail coupon lo: Quintessenz Verlags-GmbH • Ifenpfad 2-4 D-iooo Photie: + 30-74006-28 • Telefa>!: + 30/741 7805 388