Chapter 6 : Histopathological Studies of Pulpectomy in the Deciduous Teeth of Dogs

A study was performed to examine the impact of resorbable root canal filling material, Vitapex, containing calcium hydroxide and iodoform, on the physiological resorption of its roots, succedaneous permanent tooth buds and periodontal tissues. A total of 14 puppies aged 2-5 months were used; teeth were anesthetized, pulps were extirpated and immediate root canal filling was performed. These procedures were carried out in 53 deciduous teeth with 81 root canals, and contralateral intact teeth were used as controls. The animals were bred for 5 to 60 days and were tracked with radiographical and histological examinations. Results obtained were the following: 1: The form of healing observed after the experimental procedures was divided into 2 groups: those healed either by remaining vital pulp tissue or by the periodontal ligament, with 17 and 29 cases, respectively. 2: The resorption of root canal filling material and the physiological root resorption were almost the same in the majority of cases. 3: The rate of physiological root resorption in the experimental group was slightly delayed compared to that of the control group. 4: The remaining pulp tissue lesions, either in short or long term cases, comprised 5 cases of congestion, 3 cases of hemorrhage, 5 cases of mild inflammation, 11 cases of purulent inflammation, and 1 case of atrophy. 5: Periapical lesions, either in short or long term cases, comprised 6 cases with congestion, 12 cases with mild inflammation, 17 cases with purulent inflammation and 7 cases with pathological alveolar bone resorption. 6: In most cases, the lesions did not significantly affect the permanent tooth buds, except for 6 of 81 cases. 7: Pathological grades obtained in this experiment, in a total of 81 cases, were good in 41 cases (50.6%), fair in 20 cases (24.7%) and a failure in 20 cases (24.7%). 8: The best pathological grades after the experimental procedure were obtained in cases in which the root canal filling material was limited within the canal itself (flush) and in those cases which were underfilled. Overextension of root canal filling should be avoided as much as possible. 9: The relationship between root status and pathological grades showed a slightly lower incidence and favorable results with physiological root resorption compared to those without physiological root resorption. 10: In this study, the use of Vitapex for immediate root canal filling after pulp extirpation in canine deciduous teeth produced good results. Vitality of the remaining pulp and periodontal tissue was restored with subsequent physiological root resorption and without adverse effect on succedaneous permanent tooth buds.Editor, Toshiyuki KawakamiLanguage Editor, David M Carlsonviii, 232 p. ill. (some col.

Chapter 7 : Clinical and Radiographic Examinations of Pulpectomy in Deciduous Teeth

Clinical and radiographic examinations were done on 163 deciduous teeth treated with a root canal filling material called Vitapex, which contains calcium hydroxide and iodoform. Anesthesia was administered, followed by pulp extirpation and immediate root canal filling, with observation for 5 to 1307 days. The following results were obtained. 1: Excessive bleeding during pulp extirpation seemed to adversely affect the overall clinical and radiographic results. The poor clinical condition of the pulp resulted in a higher incidence of poor results based on radiographs. 2: Deciduous teeth are susceptible to overfilling after a certain period due to root resorption. A higher incidence of good pathological scores was obtained when the root canal filling was flush, not overfilled. Radiographs confirmed resorption of excess root canal filling material in all cases. 3: During the observation period, root canal filling materials were in a stable condition and only few roots exhibited resorption. Root resorption occurred earlier or at the same time as the resorption of root canal filling material. 4: During the observation period, eruption of the succeeding permanent teeth was observed in 18 cases. In 12 out of 18 cases, eruption of the succeeding tooth did not occur at the same time as on the contralateral side (control). In 6 out of 12 cases, eruption of the succeeding permanent tooth was earlier than on the contralateral side but in 4 out of 12 cases, a delay in the replacement was observed. Also, 2 cases were replaced almost immediately. 5: During the observation period, pathological root resorption was observed in cases where root canal filling material was rapidly resorbed. 6: Until the last observation day, 127 out of 163 cases (77.9%) showed no clinical discomfort or adverse radiographic findings and only 36 out of 163 cases (22.1%) showed some discomfort. 7: Signs and symptoms observed in the study were the following: 5 cases of spontaneous pain, 3 cases of pain during mastication, 10 cases of pain on percussion, 3 cases of gingival swelling, 1 case of redness, 1 case of tenderness, 3 cases of fistula and 3 cases of drainage. Discomfort was felt from the 1st to 3rd day after treatment and was mostly of a mild degree. 8: Radiographic findings of those with clinical discomfort were the following: 2 cases with loss of lamina dura, 12 cases with incomplete resorption, 8 cases with root resorption and 5 cases with pathological lesion. 9: In 36 cases with clinical discomfort and adverse radiographic findings, 12 cases (33.3%) had clinical discomfort only, 17 cases (47.2%) had clinical discomfort associated with adverse radiographic findings and 7 cases (19.5%) were asymptomatic but with adverse radiographic findings. Adverse radiographic findings were observed in 13 out of 91 cases (14.3%) in anterior and 23 out of 72 cases (31. 9%) in posterior teeth. The clinical diagnosis of cases with adverse radiographic findings was observed in the most infectious pulpitis particularly acute suppurative pulpitis and chronic hyperplastic pulpitis. 10: The overall clinical and radiographic results obtained in the study were the following: out of 163 cases, 127 obtained good results (77.9%) and 25 cases were fair (15.3%) for a total of 93. 2% had satisfactory results. Only 11 cases had poor results (6. 8%). In 151 cases with stable periodontal tissue condition from the radiograph, 117 cases obtained good results (77. 5%), 23 cases were fair (15. 2%) and 11 cases were poor (7. 3%). Resorption of about 1/4 to 2/3 of the root occurred in 12 cases, in which 10 cases obtained good results (83.3%), 2 cases were fair (16.7%) and none of the cases was classified as poor. Root canal filling immediately after anesthesia and pulp extirpation in cases with advanced root resorption was thought to be significant. 11: There was no change in the condition of the root in 92 cases until the last observation day. In 92 cases, 72 cases obtained good results (78.3%), 9 cases were fair (9.8%) and 11 cases were poor (11. 9%). The remainder of the 59 cases with root resorption became stable within the observation period. In 59 cases, 45 cases obtained good results (76.3%), 14 cases were fair (23.7%) and no case was classified as poor. Vitapex employed in root canal filling of deciduous teeth mostly did not induce clinical signs and symptoms, and adverse radiographic findings as well as affecting physiological root resorption confirming that this is an excellent root canal filling material.Editor, Toshiyuki KawakamiLanguage Editor, David M Carlsonviii, 232 p. ill. (some col.