Formocresol controversies

Formocresol controversies

1. CONTROVERSIES IN USING FORMOCRESOL AS PULPOTOMY MEDICAMENT JAMES

2. CONTENTS FORMOCRESOL PULPOTOMY ALTERNATIVES TO FORMOCRESOL PULPOTOMY GLUTARALDEHYDE PULPOTOMY FERRIC SULFATE PULPOTOMY MINERAL TRIOXIDE AGGREGATE PULPOTOMY ELECTROSURGIAL PULPOTOMY CAOH)2 PULPOTOMY MANAGING PULP EXPOSURE PULPOTOMY – CVEK PULPOTOMY ON IMMATURE PRERMANENT TEETH PARTIAL PULPOTOMY ASYMPTOMATIC PERMANENT TEETH

3. 1904 Buckley - Formocresol was introduced to treat non‑vital permanent teeth 1930, Sweet introduced the formocresol pulpotomy technique. Formocresol has subsequently become a popular pulpotomy medicament for primary teeth. Initially, the technique involved five visits. Spedding and Redig reported the results of a 5‑min formocresol protocol, and since that time, complete mummification has been abandoned by the profession. Studies have shown formocresol therapy to have a success rate between 70% and 90%. Chandrashekhar and Shashidhar: Formocresol ‑A review

4. COMPOSITION OF BUCKLEY’S FORMOCRESOL 19% formaldehyde and 35% tricresol, 15% glycerin and 31% water base.( Glycerine is added to prevent the polymerization of formaldehyde to para‑formaldehyde causing clouding of the solution) One‑fifth dilution of Buckley’s formocresol can be prepared by adding 30ml of Buckley’s formocresol , 90 ml of glycerol and 30 ml of water

5. Formaldehyde, a primary component in formocresol , Studies shown clinical success rate between 70% and 90 Instead of preserving vital pulpal tissue, chronic inflammation and necrotic tissue were found It is therefore both a bactericidal and devitalizing agent. Formocresol also inactivates the oxidative enzymes in the pulp tissue due to its protein‑binding properties and the inhibition of the enzymes disintegrates the pulp tissue resulting in ‘fixation’ of the pulp tissue being inert and resistant to enzymatic breakdown Its function is to devitalize pulps, making it inert permitting preservation of deciduous tooth It has a potent antibacterial action ,with a zone of fixation where the pulp is in direct contact with the medicament.

6. Formocresol applied to vital pulp tissue is absorbed readily into the systemic circulation and distributed throughout the body. A portion of the absorbed formocresol is metabolized and excreted by the kidney and lungs.The remaining formocresol is tissue‑bound with the liver -the predominant sites. Inhaled formaldehyde appears to be readily absorbed by the upper respiratory tract, but it is not distributed throughout the body because it is rapidly metabolized. If formaldehyde exposure occurs at a concentration of 20 ppb (parts per billion) or higher, it is instantly dangerous to health and life Ingested formaldehyde is readily absorbed by the gastrointestinal tract and exhibits little subacute toxicity after oral exposure. Exogenous formaldehyde has a biologic half‑life of 2 minutes and is quickly cleared from human plasma.

7. Human cells manage formaldehyde exposure physiologically through multiple pathways by oxidation of formaldehyde to formate . Cytosolic alcohol dehydrogenase, mitochondrial aldehyde dehydrogenase, and glutathione‑dependent and glutathione‑independent dehydrogenases are important enzymes involved in the metabolism of formaldehyde in hepatocytes, oral mucosa and nasal respiratory mucosa. Formate is the principal oxidative product of formaldehyde. Formate is further oxidized to carbon dioxide and water by the action of formyl‑tetrahydrofolate synthetase. The second active ingredient is cresol,cresol has poor solubility, so it is assumed that it does not enter systemic circulation. Cresol is highly lipophilic and has been shown to completely destroy cellular integrity. This would allow deeper tissue fixation by the formaldehyde component of formocresol

8. FORMOCRESOL PULPOTOMY TECHNIQUE After coronal pulp amputation and once hemostasis has been achieved, a cotton pellet moistened with one-fifth dilution formocresol solution is blotted and then placed in direct contact with the pulp chamber for 5 minutes. Formocresol is caustic and creates a severe tissue burn if allowed to touch the gingiva. A cement base of ZOE is placed over the pulp and allowed to set. The tooth may then be restored permanently. The restoration of choice is a preformed metal (stainless steel) crown for primary molars. On anterior primary teeth, a composite tooth-colored restoration is the treatment of choice. The use of formocresol in dentistry remains controversial. Formaldehyde, a volatile organic compound, is toxic and corrosive, especially at the point of contact. Formocresol’s other active constituent, cresol, is also an irritant and corrosive in nature Formulation of a One-Fifth Dilution of Formocresol Solution Mix 1 part Buckley’s formocresol solution with: • 1 part distilled water • 3 parts glycerin

9. When used judiciously, formocresol is a safe medicament. Formocresol , is genotoxic or immunotoxic or poses a cancer risk to children who undergo one or more formocresol pulpotomy procedures. Should be applied to the lowest dose possible for the shortest time possible to obtain the desired effect. To that end, a 1:5 dilution of Buckley’s formocresol is recommended. Until a biologic and reparative alternative has been identified that is clearly and reproducibly superior to formocresol , there are no scientific or toxicologic reasons to discontinue its use in pediatric dentistry.

10. FORMOCRESOL VERSUS GLUTARALDEHYDE In recent years, glutaraldehyde -alternative to formocresol based on its superior fixative properties, self‑limiting penetration, low antigenicity, low toxicity and elimination of cresol It is a colorless solution that has a mild odor and a boiling point of 183°C to 187°C, is soluble in water, and produces mild acidity on contamination. Glutaraldehyde is a chemically bifunctional reagent, which forms strong intra‑ and intermolecular protein bonds, leading to superior fixation by cross‑linkage. Glutaraldehyde produces a zone of tissue fixation where it is in direct contact with the pulp, while apical to this is a zone of normal tissue with few inflammatory cells. Penetration into the surrounding peri‑apical tissue is limited primarily by cross‑linkage formation. Thus, systemic distribution of glutaraldehyde is limited. Chandrashekhar and Shashidhar: Formocresol ‑A review

11. Glutaraldehyde is less necrotic, dystrophic, cytotoxic and antigenic, is a better bactericide, and fixes the tissue instantly. Glutaraldehyde appears to produce tissue fixation without causing tissue necrosis at high concentrations. At low concentrations it depresses PMN adherence at intermediate concentrations,causes inflammatory tissue damage. Prakash et al. concluded that glutaraldehyde is better fixative and less toxic agent than formocresol

12. CLINICAL AND RADIOGRAPHIC SUCCESS OF FORMOCRESOL, GLUTARALDEHYDE AND FERRIC SULFATE Over 1 year.-Internal resorption was found in all the medicaments. Clinical success was higher than the radiological success. One study failed to justify recommendation of 2% buffered glutaraldehyde solution as a substitute to formocresol as failure was observed within 6 months of treatment and failure rate was increased even after and up to 25 months. Long‑term (36 months) success rates of four different glutaraldehyde preparations (2%‑buffered and unbuffered, 5%‑buffered and unbuffered) as a pulpotomy agent in pulp exposed primary molars were evaluated. The 5% buffered solution group showed highest success rate, whereas 5% unbuffered solution showed the lowest. The canal obliteration was noted. The relative high failure rate in this long‑term follow‑up indicates that clinicians should be cautious before extensively using glutaraldehyde as pulpotomy agent

13. FORMOCRESOL VERSUS CALCIUM HYDROXIDE Calcium hydroxide was the first agent used in pulpotomies that demonstrated any capacity to induce regeneration of dentin. Calcium hydroxide adequately controls pulpal hemorrhage, to permit good contact between medicament and pulpal tissue. This seems to be important in the prevention of internal resorption may be more technique sensitive than formocresol . The inflammatory status of radicular pulp tissue at the time of treatment, providing effective coronal seal, is thought to be important to a successful outcome. Markovic et al. reported the presence of a dentine bridge above the pulp amputation site radiographically in 47% of pulpotomized teeth using calcium hydroxide. Heilig et al.performed calcium hydroxide pulpotomy in 17 carious primary molars using alternative method of hemorrhage control i.e., aluminum chloride. This study suggests that the aluminum chloride‑calcium hydroxide pulpotomy may be a viable alternative to formocresol pulpotomies

14. This material considered the ‘‘benchmark’’ for vital pulp therapy but long term study outcomes have been variable. Ca(OH)2 has been shown to be cytotoxic in cell cultures, does not exclusively stimulate reparative dentin formation, shows poor marginal adaptation to dentin, and induces pulp cell apoptosis. The material can be associated with primary tooth resorption, it can degrade and dissolve beneath restorations, and it can also suffer interfacial failure upon amalgam condensation. It produces a gap between the dentin interface when used with bonding resins. Dentin bridges beneath Ca(OH)2 are associated with tunnel defects, and the material fails to provide a long-term seal against microleakage when used as a pulp capping agent. The disintegration of Ca(OH)2 under restorations associated with defects in the dentinal bridge can provide microorganisms with a pathway for penetration into pulpal tissue and the subsequent stimulation of circulating immune cells, inducing pulpal irritation and potential pulpal calcification and canal obliteration.

15. FORMOCRESOL VERSUS ELECTROSURGICAL PULPOTOMY Another form of devitalization developed is electrosurgical pulpotomy. considered as sensitive technique It is a method of cutting and coagulating soft tissues by means of high‑frequency radio waves passing through the tissue cells. Homeostasis without systemic involvement. It is less time‑consuming than the formocresol approach. Electrocautery carbonizes and heat denatures pulp and bacterial contamination. Mack and Dean reported a very high success rate with the technique. Studies show that there is no significant difference between clinical and radiographic success rates for electrosurgical and formocresol pulpotomies. Chandrashekhar and Shashidhar: Formocresol ‑A review

16. Electrosurgery pulpotomy with either mechanical coronal pulp removal or electrical coronal pulp removal induces formation of reparative dentin. This is in the form of bridging at the pulpal amputation sites or along the canal walls. It indicates efforts to heal the area of insult. This technique also increases the fibroblastic activity at the middle and apical portions of roots with early resorption,as pulp tissue tries to renew itself with proliferation of fibroblasts. On the basis of the use of electrosurgical current intensity, there is a chance of peri‑apical or furcal involvement. In case of electrosurgery, internal resorption was noted after 4 weeks. This is due to the excess amount of heat transferred through accessory canals on floor of pulpal chamber of molars causing necrosis and internal resorption. Later, intense inflammatory cells were observed at coronal third of pulp canals and complete healing cannot be achieved in the absence of dentinal bridges

17. FORMOCRESOL VERSUS FERRIC SULFATE Ferric sulfate controls the pulpal hemorrhage and thus prevents the problems encountered due to clot formation and minimizes the inflammation and internal resorption. Shaw et al. (  1987) also found reversible damage to the connective tissue adjacent to the sulcular gingiva after application of ferric sulfate. In contact with the blood, ferric ions form a ferric complex and the membrane of this complex seals the cut blood vessels mechanically and provides hemostasis and an agglutinated protein complex, which produces a blood clot that occludes the capillary orifices. The hemostatic properties of ferric sulfate and the favorable pulpal response make it a promising medicament for pulpotomy. A clinical research was done by Fie et al. to compare the clinical and radiographic success of ferric sulfate and formocresol as pulpotomy medicaments. They demonstrated that ferric sulfate was clinically and radiographically successful as a pulpotomy medicament Chandrashekhar and Shashidhar: Formocresol ‑A review

18. After one‑year recall, the success rate of the ferric sulfate group was actually greater than that of the traditional formocresol pulpotomy group. long‑term effect on the teeth and the rest of the body was not addressed. Since formocresol is said to “mummify” or fix the pulpal tissue in root canals, pulp tissue under this agent may not be affected by the zinc oxide eugenol. Garcia‑Godoy et al. found less severe inflammation when zinc oxide eugenol was placed on formocresol ‑treated pulps. Ferric sulfate may function passively. Since ferric sulfate is not a fixative agent, the base in direct contact with the pulpal surface may play an important role in the healing process.

19. FORMOCRESOL VERSUS MINERAL TRIOXIDE AGGREGATE Mineral trioxide aggregate (MTA) is a fine hydrophilic powder developed by Mahmoud Torabinejad in Loma Linda University. It consists of tricalcium silicate, tricalcium aluminate, tricalcium oxide, silicate oxide and bismuth oxide. MTA is currently being used in pulp therapy and has been shown to provide an enhanced seal over the vital pulp .Furthermore, MTA has superior biocompatibility and is less cytotoxic than other materials currently used in pulp therapy. Previous studies showed that MTA stimulated the release of cytokines and production of interleukin which induced hard tissue formation. Schmitt et al. reported that MTA as ProRoot . can be placed in the tooth with an amalgam carrier, Messing gun MTA has also shown to revascularize and promote tissue formation

20. The pulp architecture was found to be intact and continuous odontoblastic layer was seen. While cases treated with white MTA showed dentine bridge formation along with inflammatory cells and areas of partial necrosis, more clinical and radiographic failures were seen with white MTA. Nevertheless, the evidence is becoming stronger that MTA is biologically superior and more clinically successful than formocresol . MTA can be difficult to use. Recent concern rose about the toxicity of aluminum oxide, which is present in MTA when absorbed systemically

21. MTA exhibits a superior marginal adaptation and is non- absorbabale , and when it cures in the presence of calcium ions and tissue fluids, it forms a reactionary layer at the dentin interface resembling hydroxyapatite in structure. Other biocompatible characteristics include a sustained alkaline pH after curing, small particle size, and a slow release of calcium ions.Studies have also demonstrated that MTA stimulates cytokine release, induces pulpal cell proliferation, and promotes hard tissue formation. The high alkalinity of MTA and its calcium release and sustained pH at 12.5 is most likely responsible for preventing any further microbial growth of residual microorganisms left after caries excavation. The high pH also extracts growth factors from adjacent dentin thought to be responsible for promoting dentinal bridging. Direct pulp capping with MTA has proven to be effective in stimulating tertiary dentin formation According to Tomson et al., the bioactive properties of MTA that stimulate reparative bridge formation can be attributable to the material providing a biocompatible noncytotoxic antibacterial environment. MTA also provides a favorable surface morphology for cell attachment and has the ability to form hydroxyapatite on its surface in the presence of tissue fluid.

22. MTA is hygroscopic and sets in the presence of moisture, so direct contact with tissue fluids or blood does not affect the curing properties. The close adaptation of the silicate cement produces a virtually gap-free interface owing to the small particle size and precludes microleakage and bacterial ingression. MTA may also act to entomb residual microorganisms at the dentin interface. The slow release of calcium ions also allows the material to stimulate growth factors from the dental pulp and promote signaling molecules (TGF-b, interleukin [IL]-1a, IL-b, macrophage colonystimulating factor (MCSF), that encourage hard tissue formation. The compressive strength and surface texture of the set cement allow strong bonding with adhesive restorations and minimal compression under heavy loading when a final restoration is placed.

23. Completion of dentin bridge formation with MTA and Calcium hydroxide A, After 1 week, a noticeable bridge has formed subjacent to MTA. B, A comparable bridge under calcium hydroxide after 2 weeks. C, A 4-week specimen with MTA shows excellent bridge formation. D, Consistently, the bridge formation under calcium hydroxide lagged behind MTA; an example of bridge formation under calcium hydroxide after 8 weeks

24. MINERAL TRIOXIDE AGGREGATE PULPOTOMY TECHNIQUE After completion of coronal pulp amputation and achievement of hemostasis with moist cotton pellets, MTA powder is mixed with sterile water until the powder is adherent. Excess moisture is removed from the powder by placing a dry paper point into the mixture to act as a moisture wick. The MTA may be applied to the pulp tissue using an retrograde amalgam carrier, ensuring enough material to completely cover the exposed pulp tissue to a depth of 3 to 4 mm. The MTA mixture is gently packed over the pulp tissue using the blunt end of a large paper point and a broad-ended amalgam compactor,cement base of ZOE or glass ionomer cement is placed gently over the MTA and allowed to set.

25. The MTA will take several hours to reach its optimum physical strength The tooth may then be restored permanently MTA used as a pulp capping agent in monkey teeth showed the pulp tissue responses to MTA to be superior to those produced using Ca(OH)2. MTA was found to maintain pulp integrity after pulp capping and pulpotomy and known to have a dentinogenic effect on the pulp expressed by the induction of dentin bridge formation

26. Radiograph showing caries and the presence of immature apices. mandibular left molar in a 7-year-old female patient Removal of undermined enamel. 2mm of pulp exposure after caries removal and 5.25% NaOCl hemostasis. MTA of 2.5 mm thickness placed over the entire pulpal roof. Radiograph of MTA with a moist cotton pellet Bonded composite restoration placed over cured MTA 10 days after direct pulp capping. Eight-year 4-month recall radiograph showing completed root formation. The tooth has a normal response to CO2 ice testing.

27. CVEK PULPOTOMY Cvek described a pulpotomy technique in which only the superficial 2 to 3 mm of hyperplastic inflamed tissue was removed with a water-cooled, high-speed diamond bur Hemostasis was then secured before capping with an appropriate material. If hemostasis could not be secured after several minutes of saline-moistened cotton pellet application, the preparation was checked carefully for residual superficial tags of bleeding tissue Persistent bleeding from an inflamed pulp usually indicates that the tissue should be resected at a deeper level to preserve a vital apical pulp stump

28. Hemostasis was obtained with saline, and a pulp cap of calcium hydroxide Cvek reported success in an impressive 94% to 96% of cases More recent reports suggest that histologic tissue responses may be more favorable in response to calcium silicate cements, such as MTA, than to Ca(OH)2. Thus MTA is recommended as the pulp capping agent of choice in cases that do not extend deeply into the roots, where subsequent retrieval may present a considerable challenge. Preference should be given to white MTA products in an effort to minimize the risk of unsightly tooth staining.

29. PARTIAL PULPOTOMY ON ASYMPTOMATIC YOUNG PERMANENT POSTERIOR TEETH A teeth with little or no history of pain and in the absence of radiographic signs, percussion sensitivity, swelling, or mobility. The procedure usually involves removal of 1 to 3 mm of pulp tissue suspected to be inflamed, beneath the exposure site, in order to reach underlying healthy tissue. After hemostasis, the exposure site traditionally has been covered with Ca(OH)2 and the tooth sealed with ZOE and a permanent restoration. Mejàre Cvek and Mass et al reported a 91.4% success rate in 35 cases followed for 12 to 48 months.

30. Summary VTP aims at preserving pulpal tissue and promoting repair of the mineralized tissue barrier (dentin bridge) In addition, the success of this technique would avoid pulpectomy and subsequent root canal obturation The search for alternatives to the formocresol pulpotomy in cariously exposed vital primary teeth has yet to reveal an agent, Until then ferric sulfate, MTA, or formocresol (one-fifth dilution) can be used The evaluation of the studies suggests that MTA seemed to be the material of choice after pulpotomies. Although it showed successful clinical performances over time

31. Controversy exists as to whether the pulp should be reentered after the completion of root development in the pulpotomy-treated tooth. Langeland et al. believe that pulp capping and pulpotomy procedures invariably lead to progressive calcification of the root canals. They advocated that, after successful root development, pulpectomy and root canal treatment should be performed before canals became obliterated, and difficult to manage endodontically if they did become infected.

32. Conclusion   MTA seemed to be the gold standard material in the pulpotomy of primary and permanent teeth. Promising results were also provided by biodentine CH seemed to be the most ineffective material for pulpotomies of deciduous teeth and demonstrated the worst results when compared with all tested materials The introduction of calcium-silicate-based cements (such as Biodentine ) appears to be promising for VTP. C alcium-silicate-based cements seemed to play a central role in regenerative endodontics, inducing pulp regeneration, healing and dentin formation .

33. REFERENCES Textbook of Ingle 11 th edition Textbook of Pathways of pulp- Cohen 11 th edition Seltzer and bender –Dental Pulp Chandrashekhar and Shashidhar: Formocresol ‑A review Journal of Restorative Dentistry / Vol - 2 / Issue - 3 / Sep-Dec 2014 B. morizu et lava Different Pulp Dressing Materials for the Pulpotomy of Primary Teeth: A Systematic Review of the Literature J. Clin. Med. 2020, 9, 838; Block R. Are you still using formocresol ? An update. J Tenn Dent Assoc 2009;89:14‑7 Ranly DM. Formocresol toxicity: Current knowledge. Acta Odontol Pediatr 1984;5:93‑8 Jabbarifar SE, Khademi AA, Ghasemi D. Success rate of formocresol pulpotomy versus mineral trioxide aggregate in human primary molar tooth. J Res Med Sci 2004;6:304‑7

34. Doyle WA, McDonald RE, Mitchell DF. Formocresol versus calcium hydroxide in pulpotomy. J Dent Child 1962;29:86‑97 Spedding RH, Mitchell DF, McDonald RE. Formocresol and calcium hydroxide therapy. J Dent Res 1965;44:1023‑34. Redig DF. A comparison and evaluation of two formocresol pulpotomy technics utilizing “Buckley’s” formocresol . J Dent Child 1968;35:22‑30.