ABSTRACT
Objective: This study aimed to evaluate the prevalence of root fusion and the incidence of C-shaped canals in maxillary first molar (MFM) and maxillary second molar (MSM) teeth using cone-beam computed tomography. Material and Methods: In this study, a total of 1233 MFMs and 1406 MSMs from 802 patients were analyzed. First, the number of fused rooted teeth and the type of root fusion were determined. Subsequently, incidence and number of C-shaped canals were ascertained according to the type of fusion, location, position, and level of canal merging in teeth with fused roots. Six types were established according to the C-shape configurations observed. Presence of root fusion and the C-shaped canal according to gender, age, and tooth position were evaluated by chi-square test. Values with p< 0.05 were considered significant in statistical tests. Results: The incidence of fusion in the MFM and MSM teeth was 6.16% and 22.40%, respectively. Only three MFMs (0.24%) and 3.77% of the MSMs had C-shaped canals. While the incidence of fusion was higher in women (p< 0.05), the C shaped morphology was not affected by sex (p> 0.05). Individuals over the age of 50 years had a lower incidence of C-shaped canals (p< 0.05). Conclusion: C-shaped canal morphology was more commonly associated with complex types of root fusion involving three roots; 16.83% of MSMs with fused roots had C-shaped canals (AU).
Objetivo: o objetivo deste estudo foi avaliar a prevalência de fusão radicular e a incidência de canais em C nos dentes do primeiro molar superior (MFM) e do segundo molar superior (MSM) por meio da tomografia computadorizada de feixe cônico. Material e Métodos: Neste estudo, um total de 1233 MFMs e 1406 MSMs de 802 pacientes foram analisados. Primeiro, o número de dentes com raízes fundidas e o tipo de fusão radicular foram determinados. Posteriormente, a incidência e o número de canais em forma de C foram verificados de acordo com o tipo de fusão, localização, posição e nível de fusão do canal nos dentes com raízes fundidas. Seis tipos foram estabelecidos de acordo com as configurações em forma de C observadas. A presença de fusão radicular e do canal em C de acordo com sexo, idade e posição dentária foram avaliadas pelo teste do qui-quadrado. Valores com p <0,05 foram considerados significativos nos testes estatísticos. Resultados: A incidência de fusão nos dentes MFM e MSM foi de 6,16% e 22,40%, respectivamente. Apenas três MFMs (0,24%) e 3,77% dos MSMs tinham canais em forma de C. Enquanto a incidência de fusão foi maior em mulheres (p <0,05), a morfologia em forma de C não foi afetada pelo sexo (p> 0,05). Indivíduos com mais de 50 anos apresentaram menor incidência de canais em C (p <0,05). Conclusão: a morfologia do canal em forma de C foi mais comumente associada a tipos complexos de fusão radicular envolvendo três raízes; 16,83% dos HSH com raízes fundidas tinham canais em forma de C (AU).
Subject(s)
Humans , Tooth Root , Dental Pulp Cavity , Cone-Beam Computed Tomography , MolarABSTRACT
OBJECTIVES: The purpose of this study was to investigate the incidence of root fusion and C-shaped root canals in maxillary molars, and to classify the types of C-shaped canal by analyzing cone-beam computed tomography (CBCT) in a Korean population. MATERIALS AND METHODS: Digitized CBCT images from 911 subjects were obtained in Chosun University Dental Hospital between February 2010 and July 2012 for orthodontic treatment. Among them, a total of selected 3,553 data of maxillary molars were analyzed retrospectively. Tomography sections in the axial, coronal, and sagittal planes were displayed by PiViewstar and Rapidia MPR software (Infinitt Co.). The incidence and types of root fusion and C-shaped root canals were evaluated and the incidence between the first and the second molar was compared using Chi-square test. RESULTS: Root fusion was present in 3.2% of the first molars and 19.5% of the second molars, and fusion of mesiobuccal and palatal root was dominant. C-shaped root canals were present in 0.8% of the first molars and 2.7% of the second molars. The frequency of root fusion and C-shaped canal was significantly higher in the second molar than the first molar (p < 0.001). CONCLUSIONS: In a Korean population, maxillary molars showed total 11.3% of root fusion and 1.8% of C-shaped root canals. Furthermore, root fusion and C-shaped root canals were seen more frequently in the maxillary second molars.
Subject(s)
Cone-Beam Computed Tomography , Dental Pulp Cavity , Incidence , Molar , Retrospective StudiesABSTRACT
OBJECTIVES: The purpose of this study was to investigate the incidence of root fusion and C-shaped root canals in maxillary molars, and to classify the types of C-shaped canal by analyzing cone-beam computed tomography (CBCT) in a Korean population. MATERIALS AND METHODS: Digitized CBCT images from 911 subjects were obtained in Chosun University Dental Hospital between February 2010 and July 2012 for orthodontic treatment. Among them, a total of selected 3,553 data of maxillary molars were analyzed retrospectively. Tomography sections in the axial, coronal, and sagittal planes were displayed by PiViewstar and Rapidia MPR software (Infinitt Co.). The incidence and types of root fusion and C-shaped root canals were evaluated and the incidence between the first and the second molar was compared using Chi-square test. RESULTS: Root fusion was present in 3.2% of the first molars and 19.5% of the second molars, and fusion of mesiobuccal and palatal root was dominant. C-shaped root canals were present in 0.8% of the first molars and 2.7% of the second molars. The frequency of root fusion and C-shaped canal was significantly higher in the second molar than the first molar (p < 0.001). CONCLUSIONS: In a Korean population, maxillary molars showed total 11.3% of root fusion and 1.8% of C-shaped root canals. Furthermore, root fusion and C-shaped root canals were seen more frequently in the maxillary second molars.
Subject(s)
Cone-Beam Computed Tomography , Dental Pulp Cavity , Incidence , Molar , Retrospective StudiesABSTRACT
The purpose of this study was to determine the distribution, prevalence and relationship of the localized periodontitis of root fusion in maxillary and mandibular molars. One hundred patients who had eight maxillary and mandibular molars(third molars excluded) were consecutively selected for the study subjects. The subjects provided a total of 800 molars, i.e., 400 maxillary and 400 mandibular molars. A decision about root fusion was made on the radiographic examination. Probing depth, plaque index, gingival index and mobility were measured. The results were as follows. 1. 15.9% of the molars had a fused root. 22% of the maxillary molars and 9.8% of the mandibular molars had a fused molars. 2. In maxillary molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference except plaque index of maxillary first molars group(p<0.01). 3. In mandibular molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference(p<0.01). As a result of this study, it can be concluded that, in management of molars with a root fusion, we should detect the molars through the precise radiographic examination, early periodontal treatment and systematic treatment plan should be chosen. And postoperative continuing supportive periodontal therapy is needed.
ABSTRACT
The aim of this study was to compare periodontal conditions around mesially tipped molars by a tipping degree. Patients who had been consecutively treated at the Department of Periodontology, Chonbuk National University Hospital from October 1999 to August 2001 were assessed with radiographs taken at their molar regions. Of all molars investigated, 142 molars of 116 patients tipped mesially more than 10 degrees to the line perpendicular to an occlusal plane were selected for the study. The tipped molars were divided into 2 groups with a reference to a tipping degree, i.e., 66 slightly tipped(group 1 : or =30degrees). Probing depth(PD), plaque retention index(PRI) at mesial surfaces of tipped molars and tooth mobility(TM) were recorded at the clinical examination. Tipping degree(TD) and alveolar bony defect(ABD) at the mesial surface of the molars were measured in a radiograph. The results showed that no statistical differences were found between groups in all measured variables. In Pearson correlation analysis performed in the same group, a positive relationship was shown between PRI and PD in the group 1 and, in the group 2, between PRI and PD as well as PRI and ABD(p < 0.01). However, no statistically significant relationship was found between TD and all other variables in both groups. Within limitations of this study, it may be concluded that tipping degree did not seem to influence periodontal conditions, i.e., PD, ABD and TM of mesially tipped molars per se, but plaque presence/absence seemed to mainly affect the periodontal conditions of the tipped molars.
Subject(s)
Humans , Dental Occlusion , Molar , Prevalence , ToothABSTRACT
The objective of this study was to determine the incidence and distribution of root fusion as well as its sexlinkage in maxillary and mandibular molars. One hundred fifty patients who had eight maxillary and mandibular molars (third molars excluded) were consecutively selected for the study subjects. The subjects provided a total of 1200 molars, i.e., 600 maxillary and 600 mandibular molars. A decision about root fusion was made on the radiographic examination. If a molar had one root and/or roots fused at any part in the root surface, it was considered as having root fusion. The results showed that : (1) 14.1 % of the maxillary molars and 5.8 % of the mandibular molars had a fused root, (2) the prevalence of root fusion in the male was 33 % and 56.4 % in the female, (3) 60 % in the male and 48.8 % in the female had bilaterally paired root fusion, (4) the root fusion was most frequently observed in the maxillary second molar position, but none in the mandibular first position in this study. Within limitations of this study, it can be concluded that, in management of molars with a furcation problem, treatment options such as hemisection and root amputation should be chosen after careful evaluation of root fusion. Further studies are needed to investigate a possible relationship between root fusion and periodontal disease progression.
Subject(s)
Female , Humans , Male , Amputation, Surgical , Incidence , Molar , Periodontal Diseases , PrevalenceABSTRACT
The objective of the present study was to investigate the vertical and horizontal location of the molar furcations in korean. The samples used in this study included 132 maxillary molars and 120 mandibular molars. Of them, 47 maxillary molars and 34 mandibular molars had the fused roots. So, 85 maxillary molars(54 1st and 31 2nd molars) and 86 mandibular molars(46 1st and 40 2nd molars) were measured. The vertical and horizontal location of molars were measured with divider and digimatic micrometer and their means and standard deviation calculated. The results were summarized as follows: 1. The ratio of fused roots found in this study was the highest in the maxillary second molars with 59%, followed by mandibular second molars(46%) and maxillary first molars(7%) and none were discovered in the mandibular first molars. 2. In the study of the vertical location of molar furcation, the results were as follows : In the maxillary first molars, the length in descending order were distal(5.06mm), mesial(4.52mm) and buccal(4.01mm) and in the maxillary second molar, distal(4.04mm), mesial(4.02mm) and buccal(3.87mm). In the mandibular first molar, the length was 3.69mm on the lingual side and 2.81mm on the buccal side, and in the mandibular second molar, 3.87mm on the lingual and 3.61mm on the buccal side. 3. The location of the mesial and distal furcations in horizontal dimension measured showed following results : buccal and mesial furcations of the maxillary molars and buccal and lingual furcations of the mandibular molars generally found at the center, but the mesial furcation of the maxillary molars were found approximately two thirds toward the palatal aspect.