Taurodontism and C-shaped anatomy: is there an association?

Multinational cross-sectional study and meta-analysis on radicular grooves, C-shaped canals, and taurodontism in mandibular first premolars across 20 countries

The success of root canal therapy is fully predicated upon a complete understanding of root and canal morphology and all the anatomical variations that can complicate the endodontic treatment. Of these morphological variations, taurodontism, RGs, and C-shaped canals are of note due to their implications on diagnosis, treatment planning, and endodontic success. This study aimed to investigate the prevalence and regional variations of C-shaped canals, RGs, and taurodontism across 20 countries using CBCT imaging and meta-analytic methods. A multicenter, cross-sectional study analyzed CBCT datasets from 6,000 participants (12,000 teeth) distributed equally across 20 countries. Standardized evaluation arrangements were utilized to identify RGs (RG), taurodontism, and C-shaped canals with their prevalence stratified by region, gender, and age. Statistical analyses cover subgroup comparisons, correlation studies, and sensitivity analysis using Cramer's V. RGs had a pooled global prevalence of 20%, with high-rised rates in Africa. C-shaped canals reported a 10% global prevalence, mainly in Asia, On the Other hand taurodontism was lowest prevalent at 7%, with markable regional variability. Prominent bilateral symmetry was noticed for all features, and taurodontism showed the highest rate (98.33%). Important correlations existed among C-shaped canals, grooves, and taurodontism showing shared developmental pathways. The current study points out the significant prevalence, including anatomical variations of RGs, taurodontism, and C-shaped canals in mandibular 1st premolars, with substantial demographic and regional differences. The findings highlight the importance of perception of these features' morphological interrelationships along with bilateral symmetry to increase diagnostic accuracy, clinical outcomes, and treatment planning.

C-shaped root canal systems in the bilateral mandibular first molars: a case report and literature review

BACKGROUND

Mandibular first molars typically exhibit complex root and canal anatomy. A thorough understanding of their morphological variations is crucial for endodontists to achieve successful root canal treatment. A C-shaped root canal system is a unique anatomical variation characterized by a C-shaped or semi-circular cross-sectional morphology, observed predominantly in mandibular second molars. The prevalence rate of the C-shaped root canal system is approximately 2.7-48.7% in the mandibular second molar, while the condition is rarely seen in mandibular first molars, particularly in bilateral cases.

CASE PRESENTATION

This report details an uncommon case of a C-shaped root canal system in bilateral mandibular first molars: the right molar exhibited a fused root with two separate mesial and two distal canals, while the left molar displayed a single oval mesial canal and a semicolon-shaped distal canal. To our knowledge, this is the first report of the presence of four separate canals within a fused C-shaped root in the mandibular first molar.

CONCLUSIONS

While C-shaped root variations are detected in mandibular first molars, a thorough knowledge of normal root canal anatomy and associated variations presents a significant challenge for clinicians in terms of successful endodontic treatment.

Prevalence and root canal morphology of taurodontism analyzed by cone-beam computed tomography in Northern China

BACKGROUND

To evaluate the prevalence and characteristics of taurodontism in northern China by using cone-beam computed tomography (CBCT) and assisting the treatment.

METHODS

The study involved CBCT scans of 8112 teeth from 507 participants of northern China, comprising 217 males and 290 females aged 18 to 60. Analysis was conducted using Shifman and Chanannel's criteria to assess the prevalence and attributes of taurodontism, examining differences based on tooth position (maxilla and mandible) as well as gender (P < 0.05). Specific morphology including C-shaped canal was recorded. The curvature of the canals was measured using a modified Schneider method. Moreover, we reported two failure cases with taurodontism referred to a retreatment.

RESULTS

Taurodontism was observed in 113 participants, affecting 23.50% of the males and 21.38% of the females in at least one tooth (P > 0.05). The prevalence was significant higher in maxilla (P < 0.05). The highest incidence of taurodontism was detected in premolars, 9.86% in the maxillary first premolars, and in molars, with 3.94% in the maxillary first molars. Regarding canal curvature, a higher incidence of curved canal could be found in maxillary and mandibular molars of taurodontism (47.50-66.67%), alongside an elevated prevalence of C-shaped taurodontism in mandibular second molars (71.43%). After follow-up, the healing response was satisfactory in both cases.

CONCLUSION

The study highlighted a higher incidence of taurodontism in maxilla, indicating a significant association between taurodontism, C-shaped characteristics, and canal curvature. Dentists are advised to carefully consider the presence of special morphologies during taurodontism treatment.

Association of root morphology of mandibular second molars on panoramic-like and axial views of cone-beam computed tomography

BACKGROUND

Knowledge about the anatomy and morphology of the root canal system is essential for successful surgical and non-surgical root canal treatments. However, precise assessment of the root morphology and anatomy is not often possible on two-dimensional radiographs. This study aimed to investigate the association of root morphology of mandibular second molars on panoramic-like and axial views of cone-beam computed tomography (CBCT).

METHODS

This cross-sectional study evaluated 1,231 CBCT scans of mandibular second molars obtained between October 2018 and February 2022 that were retrieved from the archives of a private radiology clinic. Panoramic-like images were reconstructed from the CBCT scans. The root morphology of mandibular second molars was classified on panoramic-like images as type 1, 2, 3, 4, or 5. The root pattern on axial CBCT images was classified into three types of single, double and C-shaped. The association of root morphology on panoramic-like and axial CBCT views was analyzed by the Chi-square test and Fisher's exact test at 0.05 level of significance.

RESULTS

Of all, 62.7% of mandibular second molars were type 1; out of which, 97.3% had a double-root pattern on axial CBCT images. Also, 28.6% of them were type 2; of which, 92.6% had a double-root pattern. Moreover, 3.9% were type 3; of which, 47.9% had a C-shaped pattern; 0.9% were type 4, and 45.5% of them showed a single-root pattern; 3.8% were type 5 with 76.6% of them showing a single-root pattern. The prevalence of C-shaped canals was higher in females, and most C-shaped canals had a C3 pattern.

CONCLUSION

Root morphology on panoramic-like CBCT views had a strong association with the root canal pattern on axial CBCT views. According to the results, mandibular second molars with a type 3 morphology on panoramic-like CBCT images are highly probable to have a C-shaped canal.

Prevalence of Taurodontism in Contemporary and Historical Populations from Radom: A Biometric Analysis of Radiological Data

Taurodontism is a morphological anomaly of multirooted molars characterized by apical displacement of the pulp chamber, shortened roots, and the absence of constriction at the dentoenamel junction. It can negatively impact the outcome of dental treatment plans. This study aimed to compare the prevalence of taurodontism among contemporary and historical populations from Radom, Poland. Five hundred eighty-two panoramic radiographs of contemporary patients and 600 radiographs of historical individuals were analyzed using the Shifman and Chanannel index. Group differences were determined with Pearson's chi-square tests according to sex, site, tooth group, and historical period. The study also evaluated the degree of severity of taurodontism in relation to dental groups, gender, and the periods from which contemporary patients as well as historical individuals originated. In the contemporary population, taurodontism was observed in 34% of individuals. In the historical data, the highest prevalence of taurodontism (31%) was observed among individuals from the 18th and 19th centuries, while earlier periods exhibited considerably lower prevalence rates. Across contemporary and historical populations, the maxillary molars were the most commonly affected teeth. Hypotaurodontism was the most prevalent form of taurodontism. The prevalence of taurodontism has gradually increased from the 11th century to the current day. The results of the research are of great importance for the clinician in terms of planning comprehensive dental treatment.

High prevalence of taurodontism in North China and its relevant factors: a retrospective cohort study

OBJECTIVE

The purpose of this study was to investigate the prevalence and relevant factors of taurodontism in North China.

METHODS

We retrospectively analysed the cone beam computed tomography (CBCT) of 1025 patients (496 male and 529 female) aged between 10 and 59 years. The crown-body/root (CB/R) ratios of the maxillary and mandibular molars were measured. The prevalence of hypotaurodontism, mesotaurodontism, and hypertaurodontism was then calculated and the incidence of taurodontism along with its relevant factors, was evaluated.

RESULTS

The overall rate of taurodontism in North China was as high as 78.9%. If the third molars (opsigenes) were excluded, which have a big morphological variation from each other, the rate was 52.4%. The mean CB/R ratio of taurodontism differs from tooth position: maxillary mandibular third molars > maxillary third molars > maxillary second molars > maxillary first molars > mandibular second molars > mandibular first molars (P < 0.05). In addition, the 1025 patients were divided into different age groups, and it was found that the mean CB/R ratio decreased with age (P < 0.05). Moreover, the CB/R ratio of the mandibular first and second molars in female patients was higher than males (P < 0.05).

CONCLUSION

This study revealed that taurodontism is widely prevalent in North China. The incidence of taurodontism increases the closer the tooth is to the back end of the dental arch, and quite a few of the maxillary and mandibular third molars teeth have tapered roots. And the taurodontism is decreased by age, as there were more affected female than male patients.

Frequency of occurrence of taurodontism in the historical population of Radom (11th-19th centuries)

OBJECTIVE

The aim of the work was to trace possible changes in the frequency of taurodontism in individuals who inhabited historical Radom from the early Middle Ages to modern periods.

DESIGN

The research was based on the analysis of X-ray images of 640 molars of individuals from the 11th/12th c. (n = 120), 14th/17th c. (n = 76), and 18th/19th c. (n = 444). Radiological images were made with the use of a portable X-ray machine, and the results were biometrically analysed using the Shiffman and Chanannel index.

RESULTS

The highest frequency of taurodontism was observed in the 18th/19th c. (31 %, 138/444). In the 11th/12th and 14th/17th centuries, this percentage was significantly lower (22 %, 26/120 vs. 16 %, 12/76). In subsequent chronological periods, no statistically significant differences between sexes in the occurrence of taurodontism were observed. The highest number of taurodontal teeth was observed among the second and first upper molars (73 % and 52 %, respectively), and the lowest number was observed among the first and second lower molars (16 % and 23 %, respectively). In all historical periods, hypotaurodont forms were most often observed.

CONCLUSIONS

Variations in the frequency of taurodontism may result from many reasons, for example environmental factors. However, it cannot be ruled out that the observed differences result from the increased migration of people to Radom in the 18th/19th century.

Variations of root and canal morphology of mandibular second molars in Chinese individuals: a cone-beam computed tomography study

BACKGROUND

The mandibular second molars demonstrate variations on root and canal morphology. The aim of this study was to investigate all the root canal morphology of mandibular second molars and analyze the morphological variations in patients by gender and age in a Chinese population use CBCT imaging.

METHODS

Cone-beam computed tomographic images of 1200 bilateral mandibular second molars were obtained from 600 patients (300 females and 300 males) who required a preoperative assessment for implant surgery, surgical removal of impacted teeth, orthodontic treatment, surgery of maxillofacial tumour and cysts or LeFort I osteotomy. CBCT images were divided into 5 groups according to age: "15-24 years", "25-34 years", "35-44 years", "45-54 years" and "≥ 55 years"; and 2 groups by gender: "females" and "males". The following information were recorded: the number of roots and canals and their morphology, the frequency and configuration of C-shaped canals by gender, age and position (left and right). The chi-square test was used to analyse differences between groups. P value of < 0.05 was considered statistically significant.

RESULTS

Of the 1200 teeth, 61% had two separate roots located mesiodistally, 35.6% had one C-shaped root. The 45.3% teeth had three canals in two-rooted mandibular second molars. The mesial root showed a Vertucci type II configuration in 28.9% cases followed by type IV(24.4%). While the distal root showed a significant higher prevalence of type I configuration in 95.6%. In the examined 1200 teeth, 430 teeth (35.8%) had C-shaped root canals. The prevalence of C-shaped root canal systems was significantly higher in females (42.5%) than in males (29.1%) (P = 0.000), and did not differ with age (P = 0.126). The 80.4% C-shaped canals were bilateral (P = 0.000) and did not differ with side (left and right) (P = 0.758).

CONCLUSIONS

The most commonly observed root morphology for the mandibular second molars was 2 separate roots with three canals.The prevalence of C-shaped root canal is 35.8% and is more higher in females than in males.

Endodontic Management of Mandibular Second Premolar with Vertucci Root Canal Configuration Type V

The diversity of root canal anatomy in permanent dentition is quite common. Understanding the basic anatomy of the root canal morphology and its variations is particularly important for successful root canal treatment. Mandibular second premolar usually consists of a single root with a single root canal. The presence of split roots in the apical third of the root with two separate root canals is quite rare. The major cause of endodontic failure in missed canals is that it harbors bacteria and other microorganisms. Careful radiographic interpretation and clinical examination of the pulp chamber will be helpful in locating canal orifices. The mandibular premolars with Vertucci type V canal configuration pose a challenge in clinical management. Identifying them early is important to aid appropriate modification in treatment protocol. In this case report, important modifications of clinical steps and application of magnification for successful management with access chamber modification are explained.

Taurodontism in maxillary and mandibular molars using cone beam computed tomography in a dental center in Saudi Arabia

BACKGROUND

Taurodontism is a dental anomaly characterized by altered crown root ratio that is often diagnosed by radiographic evaluation. A three-dimensional cone beam computed tomography (CBCT) can aid in the diagnosis and treatment of taurodontic teeth. Only one study has reported the prevalence of taurodontism in a Saudi population.

OBJECTIVE

Determine prevalence and other characteristics of taurodontism in permanent maxillary and mandibular molars, by CBCT in a dental center in Saudi Arabia.

DESIGN

Cross-sectional.

SETTING

College of dentistry.

SUBJECTS AND METHODS

The first and second molars, maxillary and mandibular, from study participants of Saudi origin from Jazan region of Saudi Arabia were evaluated for taurodontism based on the criteria of Shifman and Chanannel. The degree of taurodontism was determined by the taurodontism index. Results were tabulated for analysis and the chi-square test was applied for the differences between age groups, genders, and maxillary and mandibular teeth.

MAIN OUTCOME MEASURES

Characteristics of taurodontism.

SAMPLE SIZE

1839 teeth in 300 individuals.

RESULTS

Taurodontism was seen in 24 (8%) of the study participants and in 71 teeth (3.9%). Taurodontism was significantly more prevalent in individuals between 21 and 40 years of age. Hypotaurodontism (67.6%, n=48) was most prevalent, followed by mesotaurodontism (23.9%, n=17) and hypertaurodontism (8.5%, n=6). The maxillary molars were more commonly involved than mandibular, but the results were not statistically significant. No significant differences in gender were observed.

CONCLUSIONS

Dental clinicians should be familiar with the condition due to the clinical implications in oral surgery, endodontics and prosthodontics. The possibilities of a complex root canal system, an additional canal, difficulties in canal negotiation, instrumentation and subsequent obturation can be challenging for the clinician.

LIMITATIONS

Conducted in a single dental center hence future studies with larger sample sizes in different regions of Saudi Arabia should be conducted to more accurately measure the prevalence.

CONFLICTS OF INTEREST

None.