Pulp condition of successfully formocresol-treated primary molars

abstract — The aim of the study was to assess the state of the pulp of primary teeth successfully treated by formocresol pulpotomy. Nineteen teeth, all of them with clinically and radiographically successful treatments, were extracted 3–24 months after treatment. The pulpal condition had changed in all the teeth. Inflammatory reaction or necrosis was observed in all teeth. Dentinal resorption followed by apposition of hard tissue were common findings. In the teeth with vital tissue only in the apical area, the tissue had minor or no signs of inflammation. Microorganisms could be demonstrated in the necrotic tissue in one tooth. The wide range of pulpal conditions observed indicated that there was no typical tissue reaction to formocresol even though treatment was clinically successful. The present study confirms that the formocresol method should be regarded only as a means to keep primary teeth with pulp exposures functioning for a limited period of time.     

Morphologic and enzyme histochemical observations on the pulp of human primary molars 3 to 5 years after formocresol treatment.

The state of the pulp of twenty-seven primary teeth treated by formocresol pulpotomy (clinically and radiographically successful) was assessed 3 to 5 years after treatment. A wide variation was found in the pulpal condition, from normal pulp tissue to total necrosis. Resorption and apposition of hard tissue were common findings. Five teeth were freeze-sectioned and incubated for histochemical demonstration of oxidative enzymes. The pulps of two teeth were vital; two teeth had necrotic areas subjacent to the amputation paste; and one pulp was totally necrotic. Six teeth were extracted 5 minutes after formocresol pulpotomy and incubated for demonstration of oxidative enzymes. An unstained zone, 1 to 2 mm. deep, was seen in all incubated sections. In conclusion, it seems that the formocresol method should be regarded only as a means to keep primary teeth with pulp exposures functioning for a relativley short period of time.     

Evaluation of the carbon dioxide laser on vital human primary pulp tissue.

PURPOSE: The purpose of this study was to evaluate the response of the human primary pulp to the carbon dioxide laser and formocresol for vital pulp therapy. METHODS: Fifteen healthy children with intact, caries-and-restoration-free, contralateral primary cuspids with at least two-thirds of the roots remaining who were scheduled for orthodontic extraction were randomly assigned to pulpotomy treatment with a carbon dioxide laser or formocresol. The treated teeth were clinically and radiographically evaluated at 28 and 90 days post-treatment prior to extraction. The extracted teeth were evaluated histologically for pulpal response. RESULTS: All teeth were asymptomatic and clinically normal at both observation periods. Internal root resorption was observed in one formocresol and two laser treated teeth. There was a significant inverse correlation between the laser energy applied to the pulp and the degree of inflammation at 28 days (P = .01) but not at 90 days (P = .27). CONCLUSION: Carbon dioxide laser treatment compared favorably to formocresol for pulpotomy in primary teeth.     

Effects of Nd:YAG laser pulpotomy on human primary molars

The purpose of this study was to compare the effects of Nd:YAG laser pulpotomy to formocresol pulpotomy on human primary teeth. Patients with a primary tooth that required pulpotomy because of pulpal exposure to caries, were selected for this study. After removal of coronal pulpal tissue, Nd:YAG laser at 2 W, 20 Hz, 100 mJ or a 1:5 dilution of formocresol was introduced into the canal orifice for complete hemostasis. IRM paste was then placed over the pulp stump, and the tooth was restored either with composite resin or stainless steel crown. Sixty-eight teeth were treated with Nd:YAG laser and followed up for 6 to 64 months. Clinical success was achieved in 66 out of the 68 teeth (97 %), and 94.1 % were radiographically successful. In the control group, 69 primary molars were treated with formocresol and followed up for 9 to 66 months; 85.5 and 78.3% achieved clinical and radiographic success, respectively. The success rate of Nd:YAG laser pulpotomy was significantly higher than that of formocresol pulpotomy. The permanent successors of the laser-treated teeth erupted without any complications.     

Clinical, radiographic and histological analysis of the effects of mineral trioxide aggregate used in direct pulp capping and pulpotomies of primary teeth

Background : Primary teeth pulp exposures have traditionally been treated with formocresol or ferric sulphate pulpotomies or calcium hydroxide pulp capping. The aim of this study was to observe the tissue response when mineral trioxide aggregate (MTA) was used.
Methods : Ten primary teeth had direct pulp caps and 11 had a pulpotomy with MTA. The teeth were restored and then clinically reviewed monthly for five months and before extraction. Radiographs were taken prior to treatment, after one month and prior to extraction. After extraction, the teeth were examined histologically and the responses to treatment were assessed.
Results : One pulpotomy and two pulp capping cases had postoperative pain and signs of pulp degeneration. Radiographs showed no root resorption, no periodontal pockets and no furcation radiolucencies. No cases had draining sinuses or increased mobility. Most pulps responded favourably from a clinical perspective although a variety of responses were noted Histologicallyormal odontoblasts, irregular odontoblasts, intrapulpal calcifications, dentinal bridges, cementum formation, internal resorption, inflammatory infiltrate and pulp necrosis.
Conclusions : The responses of pulps in primary teeth to MTA pulpotomies and pulp caps were favourable from clinical and radiographic perspectives although a variety of histological responses were noted. MTA may be a favourable material for pulp capping and pulpotomies in primary teeth.     

Comparison of mineral trioxide aggregate and formocresol as pulp-capping agents in pulpotomized primary teeth

PURPOSE: The aim of this study was to use clinical, radiographic, and histologic examinations to compare the relative success of gray mineral trioxide aggregate (MTA), white MTA, and formocresol as pulp dressings in pulpotomized primary teeth. METHODS: Twenty-four children, each with at least 3 primary molars requiring pulpotomy, were selected for this study's clinical and radiographic portion. An additional 15 carious primary teeth planned for serial extraction were selected for this study's histologic portion. All selected teeth were evenly divided into 3 test groups and treated with pulpotomies. Gray MTA was used as the pulp dressing for one third of the teeth, white MTA was the dressing for one third, and the remaining one third were treated with formocresol. The treated teeth selected for the clinical and radiographic evaluations were monitored periodically for 12 months. The treated teeth selected for histologic study were monitored periodically and extracted 6 months postoperatively. RESULTS: Four children with 12 pulpotomized teeth failed to return for any follow-up evaluations in the clinical and radiographic study. Of the remaining 60 teeth in 20 patients, 1 tooth (gray MTA) exfoliated normally and 6 teeth (4 white MTA and 2 formocresol) failed due to abscesses. The remaining 53 teeth appeared to be clinically and radiographically successful 12 months postoperatively. Pulp canal obliteration was a radiographic finding in 11 teeth treated with gray MTA and 1 tooth treated with white MTA. In the histologic study, both types of MTA successfully induced thick dentin bridge formation at the amputation sites, while formocresol induced thin, poorly calcified dentin. Teeth treated with gray MTA demonstrated pulp architecture nearest to normal pulp by preserving the odontoblastic layer and delicate fibrocellular matrix, yet few inflammatory cells or isolated calcified bodies were seen. Teeth treated with white MTA showed a denser fibrotic pattern, with more isolated calcifications in the pulp tissue along with secondary dentin formation. CONCLUSIONS: Gray MTA appears to be superior to white MTA and formocresol as a pulp dressing for pulpotomized primary teeth.     

Clinical, radiographic, and histopathologic evaluation of Nd:YAG laser pulpotomy on human primary teeth

The purpose of this study was to compare clinical, radiographic, and histopathologic effects of Nd:YAG laser pulpotomy to formocresol pulpotomy on human primary teeth. Patients with at least two vital primary molar teeth that required pulpotomy, because of pulpal exposure to caries, were selected for this study. After hemorrhage control, complete hemostasis into the canal orifice was achieved by exposure to Nd:YAG laser (1064 nm) and an He-Ne laser (the aiming beam of the Nd:YAG laser) in noncontact mode at 2 W, 20 Hz, 100 mJ, or was achieved by applying 1:5 dilution of formocresol. Forty-two teeth in two groups were to be followed up clinically and radiographic at 1, 3, 6, 9, and 12 months. Eighteen teeth planned for serial extractions were selected for histopathologic study. The teeth were extracted at 7 and 60 days. The teeth in the laser group had a clinical success rate of 85.71% and a radiographic success rate 71.42% at 12 months. The teeth in the formocresol group had a clinical and radiographic success rate of 90.47% at 12 months. There were no statistically significant differences between laser and formocresol group with regard to both clinical and radiographic success rates. There was a statistically significant difference between 7- and 60-day laser groups with regard to inflammatory cell response criteria. Dentin bridge was absent in all samples. No stained bacteria were observed in any of these samples. In conclusion, Nd:YAG laser may be considered as an alternative to formocresol for pulpotomies in primary teeth.     

Vital pulp therapy with new materials for primary teeth: new directions and Treatment perspectives

Vital pulp therapy aims to treat reversible pulpal injury and includes 2 therapeutic approaches: (1) indirect pulp treatment for deep dentinal cavities and (2) direct pulp capping or pulpotomy in cases of pulp exposure. Indirect pulp treatment is recommended as the most appropriate procedure for treating primary teeth with deep caries and reversible pulp inflammation, provided that this diagnosis is based on a good history, a proper clinical and radiographic examination, and that the tooth has been sealed with a leakage-free restoration. Formocresol has been a popular pulpotomy medicament in the primary dentition and is still the most universally taught pulp treatment for primary teeth. Concerns have been raised over the use of formocresol in humans, and several alternatives have been proposed. Controlled clinical studies have been critically reviewed, and mineral trioxide aggregate and ferric sulfate have been considered appropriate alternatives to formocresol for pulpotomies in primary teeth with exposed pulps. In most of the studies reviewed, the caries removal method has not been described. The use of a high-speed handpiece or laser might result in an exposure of a "normal" pulp that would otherwise not be exposed.     

Pulp bleeding color is an indicator of clinical and histohematologic status of primary teeth

Objectives

This study was carried out to investigate whether the changes in hematologic characteristic and color of pulpal bleeding is associated with clinical and histologic status of the pulp in primary teeth.

Materials and methods

A total of 211 primary molars in 103 patients, 3–6 years old, were treated. One hundred eight teeth had pulpectomy, 57 teeth had pulpotomy after pulp exposure during caries excavation, and 46 teeth had pulpotomy after accidental pulp exposure in sound dentin. After pulpal exposure, pulpal blood was collected in capillary tubes for blood color and hematologic assessment. Coronal and radicular pulp tissues were amputated for histologic assessment.

Results

Blood color was significantly darker in pulpectomy cases and samples with severe inflammation. The differences were clinically perceptible by the human eye. A significant negative correlation was detected between white blood cell (WBC) count and blood color. The counts of neutrophils and lymphocytes were significantly different between treatment groups. In addition, WBC, eosinophil, monocyte, neutrophil, and basophils counts were significantly different between degrees of inflammation in coronal pulp. Moreover, severe inflammation was higher in pulpectomy group versus pulpotomy groups. Pulp tissue calcification was also significantly higher in the pulpectomy cases.

Conclusions

Considering the significant difference in pulpal blood color between the pulpectomy and pulpotomy cases, and between the different levels of pulpal inflammation; blood color can be a valid clinical diagnostic criterion of pulpal status and can be used for the selection of appropriate pulp treatment strategy.

Clinical relevance

This study shows that pulp bleeding color can be used for selection of an appropriate pulp treatment method in primary teeth.

     

Histological evaluation of electrosurgery and formocresol pulpotomy techniques in primary teeth in dogs.

The purpose of this study was to compare pulpal and periapical tissue reactions to electrosurgery versus formocresol pulpotomy techniques in the primary teeth of dogs. The study was conducted on 33 primary teeth of three mongrel dogs between the ages of one to three months. Each dog had three teeth treated by Formocresol Pulpotomy with Mechanical Coronal Pulp Removal (FC), three teeth treated by Electrosurgery Pulpotomy with Mechanical Coronal Pulp Removal (ES/MCPR), three teeth treated by Electrosurgery Pulpotomy with Electrosurgical Coronal Pulp Removal (ES/ECPR), and two teeth serving as untreated Controls. Dogs one, two and three were sacrificed performing the pulpotomies at two, four and six weeks, respectively. The pulp, periapical tissue and after surrounding bone were submitted to histological examination and the histological reaction was recorded. The results were fourteen out of 18 unfavorable and zero out of three favorable histological reactions occurred in the FC treated teeth. Six out of 18 unfavorable and one out of three favorable histological reactions occurred in the ES/MCPR treated teeth. Nine out of 18 unfavorable and two out of three favorable histological reactions occurred in the ES/ECPR treated teeth. One out of 18 unfavorable and zero out of three favorable histological reactions occurred in the untreated Control teeth. The conclusion of this study is that of the three experimental groups, the teeth treated by Electrosurgery Pulpotomy with either Mechanical or Electrosurgical Coronal Pulp Removal exhibited less histopathological reaction than the teeth treated by Formocresol Pulpotomy.     

Outcome of formocresol/ZOE sub-base pulpotomies utilizing alternative radiographic success criteria

PURPOSE: The purposes of this investigation were to 1) measure success of a primary tooth pulpotomy technique that applies formocresol in the sub-base without the common five-minute application of a formocresol impregnated cotton pellet; and 2) compare success rates of the pulpotomy procedure using traditional criteria found throughout the literature with new criteria recently established, excluding internal resorption as a radiographic failure. METHODS: Clinical and radiographic data were collected from a retrospective chart review of patients receiving formocresol pulpotomies with the application of formocresol in the zinc oxide-eugenol sub-base. RESULTS: Clinical and radiographic data were available for 196 primary molars in 122 children (followup=six to 103 months; mean=49 months). Traditional assessment of radiographic success and failure yielded a success rate of 79%. Alternative assessment excluding internal resorption as a failure yielded a 99% success rate. Most frequently observed pulpal responses were calcific metamorphosis and internal resorption. Overall clinical success was 99%. Two of the 196 teeth were extracted due to failure. A survival analysis demonstrated that the overall probability of survival remained high over time with a cumulative survival of over 95% after six years. CONCLUSIONS: The overall success rates in this study indicate that the formocresol pulpotomy technique incorporating formocresol in the zinc oxide-eugenol sub-base is a very successful treatment modality for primary molars requiring pulp therapy.     

Antibody formation to dog pulp tissue altered by formocresol uithin the root canal.

After pulpal extirpation of twenty teeth in each of five dogs, these animals were primarily immunized intramuscularly by combining formocresol with the dog's own pulp (three dogs), saline solution with pulp (one dog) and injecting sheep erythrocytes (one dog). A sixth dog was used as a control for the Arthus skin test. Secondary immunizations were accomplished via the root canal every 7 days over a 28-day period. Arthus skin-test reactions demonstrated less of a response to the formocresol alone than when the dogs' pulp was conbined with this material. In vitro analysis of hemagglutinating antibody titer showed a tremendous increase when pulp was incubated with formocresol as compared to the saline-treated pulp. Therefore, dogs' pulp tissue became antigenically altered by the formocresol recognized by the host, and a specific humoral response resulted.     

A clinical study of ferric sulfate as a pulpotomy agent in primary teeth.

Pulpotomies were performed on 83 primary molars in 62 patients. Ferric sulfate or formocresol was placed on the pulpal stumps, and teeth were followed for 3-, 6-, and 12-month periods. After the one-year follow-up, 28 of 29 teeth treated with ferric sulfate (FS group) were considered successful and 21 of 27 teeth treated with formocresol (FC group) were judged to be successful. The FS group demonstrated greater combined clinical and radiographic success than the FC group at the one-year recall (P < 0.05). Although the results of this study are promising, further study with longer observation periods is warranted before this technique can be recommended.     

Histologic analysis of pulpal revascularization of autotransplanted immature teeth after removal of the original pulp tissue.

The survival rate of replanted and autotransplanted teeth is mainly affected by the reaction of the pulp. Pulpal necrosis can cause periapical inflammation and inflammatory root resorption. The purpose of this study is to learn more about the pulpal changes in autotransplanted immature teeth whose pulp tissue was removed before transplantation. The experimental material consisted of 16 single-rooted teeth with open apices, from a beagle dog (3 months of age). At day 0, 4 teeth were extracted, the pulpal tissues were removed, and the teeth were then transplanted to their contralateral side. The same procedure was carried out on days 9, 16, and 23, each time for 4 single-rooted teeth. Longitudinal paraffin sections were made for histologic investigation. The results showed that, after 7 days, 2 of the 4 teeth had an ingrowth of new tissue over one fourth of their length. After 14 days, all 4 teeth had ingrowth (> or =one fourth of the pulp chamber). At the 21-day observation, more than half of the pulp chambers of all teeth were filled, and, after 30 days, there was total ingrowth in 3 of the 4 teeth. This new tissue consisted of well-organized and well-vascularized connective tissue.     

Prognosis of root-fractured permanent incisors

Abstract The prognosis of 56 root-fractured permanent incisors was evaluated clinically and radiographically for 2 to 31 years. Information about initial case histories, examination and treatment of root-fractured teeth were recorded retrospectively from patient cards. Most of the-root fractures occurred in the 16–20 year age group (38%) followed by the 11–15 year age group (29%). Males were involved more often than females. Fifty-two percent of the patients visited the dental clinic with in the first week, while 48% did so 1 month-31 years later alter the injury. The leading cause of root fractured injuries was falls (46%) and mostly involved one tooth (71%). Maxillary central incisors were the most often affected teeth (95%). The most common type of root fracture was in the middle third of the root (57%) followed by apical part (34%). About 59% of untreated or splinted teeth maintained their vitality. Healing with connective tissue was observed in 19 teeth, with calcified tissue in 15 teeth and with osseous tissue in only one tooth. There was partial or complete obliteration of the pulp space in these healed cases (62.5%). The formation of pulpal hard tissue produced no additional clinical problems. Partial or total pulp necrosis were noted in 21 (37.5%) teeth. Endodontic treatment was successful in 12 cases. The remaining 9 teeth were extracted due to the loss of marginal alveolar bone and apical periodontitis.     

Comparative investigation of clinical/radiographical signs of mineral trioxide aggregate and formocresol on pulpotomized primary molars

The objectives of this study were (1) to evaluate clinically and radiographically the effects of mineral trioxide aggregate (MTA) as a pulp dressing after coronal pulp amputation (pulpotomy) in primary molars, (2) to compare the effects of MTA and formocresol in pulpotomized primary teeth. Sixty primary mandibular molars of thirty healthy children aged between 5-8 years were treated by conventional pulpotomy technique. The teeth on the right side are assigned to MTA (Group A) and the left side for the Formocresol (Group B). The children were examined clinically and radiographically every 6 months over a period of 36 months. Results of present study revealed that both MTA and Formocresol has the same effect on the first as well as second primary molars, with chi-square value being 1.1483 (P ≥ 0.05). None of the teeth in either group showed any clinical pathology, showing 100% success rate but radiographically formocresol group showed one case of internal resorption that was regarded as failure in the present study. MTA seems to be more promising predictable with positive response in vital pulp therapy in future than formocresol pulpotomy except for the cost factor.     

An investigation of the relative efficacy of Buckley's Formocresol and calcium hydroxide in primary molar vital pulp therapy

OBJECTIVE: To compare the clinical and radiological outcomes following two different, single visit vital pulp therapy techniques, in cariously exposed primary molar teeth. SETTING: A paediatric dental clinic within the Dental Hospital, Newcastle upon Tyne, UK. SUBJECTS: Fifty two child patients were sequentially enrolled in the clinical investigation, 26 males and 26 females with an age range of 3.3-12.5 years. Primary molar teeth requiring vital pulp therapy were randomly allocated to either the formocresol group (F) or the calcium hydroxide group (C). The total number of teeth treated was 84. DESIGN: Recruitment was on the basis of strict inclusion criteria. Coronal pulp amputation was prescribed only in teeth with vital, cariously exposed pulp tissue. Treatment was undertaken between October 1994 and December 1996. All cases were reviewed using predefined clinical and radiological criteria. The statistical tests used were logistic regression of a triple nested data structure, chi-squared analysis of equality of treatment and probability of success with relation to subject age. RESULTS: Eighty-four cariously exposed primary molars required vital pulp therapy. Forty six (55%) teeth were included in the F group and 38 (45%) allocated to the C group. Five teeth were lost to follow-up, leaving 79 teeth: forty four (56%) in group F and 35 (44%) in group C. Eighty four percent (37/44) of teeth treated with formocresol and 77 percent (27/35) treated with calcium hydroxide were classed as clinically and radiographically successful at the cut-off date, December 1997, after a mean clinical review of 22.5 months (range 6.1-38.5 months) and a mean radiographic review of 18.9 months (range 1.3-36.9 months). CONCLUSION: This investigation confirms the clinical efficacy of a one-fifth dilution of Buckley's Formocresol as an agent in pulp treatment of cariously exposed, vital primary molar teeth. However, calcium hydroxide in its pure, powder form is a clinically acceptable alternative when combined with strict selection criteria for this method of restorative care. There was a statistically insignificant difference in successful clinical and radiological outcome between the two treatment groups. Success was unrelated to the duration of time taken to achieve haemostasis and the presence or absence of bleeding after placement of the medicament.     

Dentin formation in formocresol pulpotomized primary monkey teeth studied by tetracycline and 3H-proline incorporation.

The influence of formocresol treatment on the pulp tissue of 24 primary monkey teeth was studied using tetracycline and 3H-proline labeling techniques. Six untreated monkey teeth served as controls. The tetracycline labeled teeth were examined between 352 and 600 d, following treatment. The 3H-proline labeled teeth were observed over a period of 22-607 d, the isotope being administered 15 d before extraction. The labeling was evaluated in the coronal, middle and apical area of the roots. Dentin formation as indicated by tetracycline labeling was observed in both control teeth and successfully treated teeth, as well as in some of the unsuccessfully treated teeth. The average dentin formation rate per day varied from 1 micrometer in the control teeth to 0.14 micrometer in the pulpotomized teeth (P less than 0.01). Success of treatment was of significant importance for the amount of dentin formation (P less than 0.001). Labeling with 3H-proline, indicating collagen synthesis, could be observed in the pulp and predentin of the majority of areas judged to be normal, degenerated or inflamed. Labeling was not observed in fixed or necrotic tissue. In degenerated pulp tissue the proline labeling was clearly reduced. The findings indicate that dentin formation and collagen synthesis may take place in formaldehyde influenced pulp tissue although at a decreased rate.     

Mineral trioxide aggregate vs. formocresol in pulpotomized primary molars: a preliminary report

PURPOSE: The aim of this study was to compare the effect of mineral trioxide aggregate (MTA) to that of formocresol (FC) as pulp dressing agents in pulpotomized primary molars with carious pulp exposure. METHODS: Forty-five primary molars of 26 children were treated by a conventional pulpotomy technique. The teeth were randomly assigned to the MTA (experimental) or FC (control) group by a toss of a coin. Following removal of the coronal pulp and hemostasis the pulp stumps were covered with an MTA paste in the experimental group. In the control group, FC was placed with a cotton pellet over the pulp stumps for 5 minutes and removed; the pulp stumps were then covered by zinc oxide-eugenol (ZOE) paste. The teeth of both groups were restored with stainless steel crowns. Eighteen children with 32 teeth arrived for clinical and radiographic follow-up evaluation ranging from 6 to 30 months. RESULTS: The follow-up evaluations revealed only one failure (internal resorption detected at a 17 months postoperative evaluation) in a molar treated with formocresol. None of the MTA-treated teeth showed any clinical or radiographic pathology. Pulp canal obliteration was observed in 9 of 32 (28%) evaluated molars. This finding was detected in 2 out of the 15 teeth treated with FC (13%) and in 7 out of the 17 treated with MTA (41%). CONCLUSION: MTA showed clinical and radiographic success as a dressing material following pulpotomy in primary teeth and seems to be a suitable replacement for formocresol in primary teeth.     

Endodontic treatment of primary teeth

Endodontic treatment of primary teeth is undertaken by indirect pulp capping, direct pulp capping, formocresol pulpotomy and pulpectomy. The same treatment principles apply to both primary and permanent teeth with infected or necrotic pulps. The main differences are the use of formocresol for root canal medication and a resorbably zinc-oxide and eugenol paste for root canal obturation.