Furcation entrance dimension, divergent angle and length of CEJ to furcation entrance relate to periodontal therapy

Abstract

In previous studies we have investigated the furcation entrance dimension (FED), furcation entrance angle (FEA) and the distance between cementoenamel junction and furcation entrance (CEJ-FE) of the first and second molars and compared the Chinese with the Caucasians. The aim of the present study was to relate the FED, FEA, and distance of CEJ-FE to the clinical significance of periodontal therapy of molar furcations. All the FEDs, FEAs, and distance of CEJ-FEs of the molars were measured by a stereomicroscope equipped with a Bioscan OPTIMAS Image Analyzer and statistically analyzed by Student's paired t-test, multiple regression of ANOVA and correlation analysis. The results are summarized below. (1) There is a significant relationship between FEA and location of buccal, mesial, and distal furcations of maxillary first and second molars (16& 26, p < 0.001; 17&27, p < 0.01). (2) There exists a significant relationship between FEA and FED in the mandibular first and second molars. (3) There exists a significant relationship between FED and FEA in the mandibular second molar (r = 0.370, p < 0.05). (4) The prevalence of mean FED and FEA (type D, FED < or = 0.75 mm and FEA < or = 90 degree) of the maxillary first molar (45%) is twice as high as the maxillary first molar (24%). (5) The prevalence of type D of the buccal (32%) and lingual (37%) furcations on the mandibular second molar is markedly higher than the first molar (buccal = 12%; lingual = 4%, respectively). These results reveal that those topographics of the FED, FEA, and distance of CEJ-FE in second molars have poor prognosis in periodontal therapy when compared with first molars.