OBJECTIVESTo investigate the prevalence, unilateral/bilateral concurrency, and external morphology of permanent mandibular molars (PMMs) with radix entomolaris (RE) and radix paramolaris (RP) in a ...sample from Slovenia.DESIGNMedium field-of-view cone-beam computed tomography images of 1315 participants (681 males, 634 females) aged 13-90 years (mean age 45.5) were retrospectively examined. A total of 1363 first, 1824 second, and 1314 third PMMs were evaluated. The external morphology of the affected teeth was categorized according to Carlsen and Alexandersen's classifications.RESULTSThe individual-level RE frequencies in the first, second, and third PMMs were 1.6%, 1.9%, and 10.1%, respectively. The respective RP frequencies were 0%, 1.8%, and 3.2%. The first PMMs exclusively exhibited type A RE morphology, whereas in the second and third PMMs, types B and AC morphologies predominated. Bilateral concurrence rates were low (0-7.1%), with the exception of type A RE in first PMMs (62.5%). RE occurrences in the first and second PMMs were correlated (odds ratio = 70.2; 95% confidence interval 17.4 -282.7; P < 0.001). In concurrent cases, the second PMM followed its anterior neighbor in expressing type A morphology, and conversely, all affected second PMMs standing next to a two-rooted first PMM exhibited non-type A morphology.CONCLUSIONSIn this sample, the first and second PMMs exhibited low supernumerary root frequencies comparable to those of other European samples. The third PMM was most often affected. The presence of RE on the first PMM increased the possibility of its presence on the adjacent second PMM and vice versa.
This study examined the root morphology of mandibular first molars (MFMs) with radix entomolaris (RE), which presents diagnostic and therapeutic challenges for clinicians.
A total of 17 three-rooted ...MFMs were taken from a collection of extracted teeth. Root lengths and levels of furcations were measured with a digital calliper. The pulp floor configuration, root canal systems, and RE canal curvatures were evaluated using the cone-beam computed tomography scans.
Radix entomolaris was either located disto-lingually, with its coronal portion fixed to the distal root (n = 16) or mid-lingually (n = 1). A literature search identified four additional cases of MFMs with RE located mid-lingually. In the present study, RE was significantly (p ≤ 0.001) shorter than the distal root (DR) and the mesial root, on average by 2.04 mm and 3.15 mm, respectively. The level of the distal furcation was significantly (p = 0.003) lower than that of the mesiodistal furcation, on average by 1.39 mm. The average divergence angle formed by the cervical portions of the RE and DR canals was 53.14°. All RE canals were severely curved (> 25°) in buccolingual direction. The RE orifice was located slightly disto-lingually to considerably mesio-lingually from the DR orifice.
The traditional assumption of a disto-lingually located RE needs to be changed, even though this is the most prevalently found variant of this anatomy. The additional variant includes the presence of a mid-lingually located RE, which has implications for the endodontic access cavity design.
A 2.5-year-old intact male Irish setter was presented for a draining tract associated with the right mandibular first molar tooth (409). Conscious oral examination yielded two draining tracts ...associated with the right mandibular first molar tooth. No obvious missing teeth or other gross abnormalities associated with the oral cavity were observed. Upon anesthetized radiographic evaluation, the presence of an unerupted, abnormally positioned, supernumerary premolar tooth was observed. The following article describes the extraction of the right mandibular first molar tooth (409) as well as the unerupted supernumerary premolar tooth with associated supernumerary root and the diagnostic approach taken for this uncommon abnormality.
Teeth with a supernumerary root, such as a double, additional, extra, or accessory root, or multiple roots, are a deviation from the general form. A supernumerary root can occur in nearly all types ...of permanent teeth, while it is extremely rare in deciduous teeth. In Japan, there are only a few clinical reports of such an occurrence in maxillary and mandible primary canines, or maxillary second and mandibular primary molars, while clinical reports of a maxillary primary central incisor with a supernumerary root are available. Here, we report a case of a maxillary primary central incisor with an additional root that caused disturbance of permanent tooth eruption.
A border collie (male, nine years and five months old) presented with left infraorbital swelling and severe calculus deposition on the left maxillary fourth premolar. An oral examination revealed ...presence of gingival swelling around the left maxillary fourth premolar and drainage from the buccal gingiva located around the distal root apex. Radiography revealed bone resorption around the distal root of the third premolar and the medial and distal root apexes of the fourth premolar in the left maxilla, and a deformity of the distal root of the fourth premolar. Based on these findings, the dog was diagnosed as having internal dental fistula caused by periapical lesions and underwent extraction of the left maxillary third and fourth premolars. The fourth premolar had four roots, and there was a fissure in the crown. Histological examination showed inflammatory cell infiltration in the gingiva, pulp necrosis of the fourth premolar, and bacterial colonies around the lesions. The supernumerary root had fissures in the crown. These fissures may have served as the path for the infection in the root apexes. Abnormal morphological changes such as supernumerary roots and fissures in the crown may contribute to the onset of periapical lesions.
Abstract Introduction The aim of this retrospective study was to determine the prevalence of three-rooted mandibular permanent first molars among the Indian population by using periapical ...radiographs. Methods Five hundred eighty-six patients (320 females and 266 males) were selected, with at least 1 mandibular first molar. A total of 1054 periapical radiographs of mandibular first molars, comprising 526 right side and 528 left side, were included. The radiographs were taken at 30-degree mesial angulation and were evaluated by using the magnifying lens. The incidence, gender, and symmetry of three-rooted mandibular first molars were recorded and analyzed by using the χ2 test. Results The prevalence of three-rooted mandibular first molars was 5.97% for all patients and 4.55% for all teeth, respectively. The incidence of bilateral symmetrical distribution was 37.14%. The incidence was 6.88% for female patients and 4.89% for male patients (χ2 = 1.02, P > .05) and 4.94% for the right side and 4.17% for the left side, respectively (χ2 = 0.36, P > .05). No statistically significant differences were found between female and male patients and between the right-side and left-side occurrences. Conclusions Clinicians should be aware of the high racial prevalence of this unusual root morphology in mandibular first molars among the Indian population before and during the root canal treatment of three-rooted mandibular first molars.
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