Prevalence, Severity, and Description of Dental Anomalies in Children Treated for Acute Lymphoblastic Leukemia

Purpose: To assess the prevalence and severity of and describe dental anomalies in children treated for acute lymphoblastic leukemia (ALL) under recent Dana-Farber Cancer Institute (DFCI) protocols. Methods: Patients aged between 14 and 25 years old having received a diag- nosis of ALL before the age of 11 years and after September 2000 received clinical and radiographic oral examinations. Results: Dental anomalies were observed in 26 (51.0 percent) of 51 subjects. Microdontia was the most prevalent dental defect (39.2 percent). Impacted permanent second molars were observed in five (9.8 percent) patients. Being age five years or younger at diagnosis significantly increased the prevalence and severity of dental anomalies (P<0.001). Conclusions: Recent DFCI protocols showed a decreased prevalence of dental disturbances. The anomalies observed may still alter the development of the dental arches and occlusion in pediatric ALL survivors. Further research is needed to confirm the association between ALL treatment and permanent second molar impaction.

Is there an association between molar incisor hypomineralization and developmental dental anomalies? A case-control study

BACKGROUND

The aim of this study was to determine whether there is any association between molar incisor hypomineralization and developmental dental anomalies.

METHODS

Two pediatric dentists evaluated panoramic radiographs of 429 children aged 8-14 years with molar incisor hypomineralization (study group) and 437 children without molar incisor hypomineralization (control group) in terms of developmental dental anomalies. Twelve different developmental dental anomalies were categorized into four types: size (microdontia, macrodontia); position (ectopic eruption of maxillary permanent first molars, infraocclusion of primary molars); shape (fusion, gemination, dilaceration, taurodontism, peg-shaped maxillary lateral incisors); and number (hypodontia, oligodontia, hyperdontia) anomalies.

RESULTS

No significant difference was observed in the frequencies of developmental dental anomalies between the study and control groups in total, females, and males (p > 0.05). A statistically significant difference was found between the distribution of developmental size, position, shape, and number anomalies between the study and control groups (p = 0.024). The most common anomaly in both groups was hypodontia (6.3% and 5.9%, respectively). There was a significant difference between the study and control groups in terms of subtypes of shape anomaly in all children and females (p = 0.045 and p = 0.05, respectively).

CONCLUSIONS

While a significant difference was observed between the distributions of types of developmental dental anomalies between individuals with and without molar incisor hypomineralization, there was no difference in terms of the frequency of developmental dental anomalies.

Guidance for Permanent First Molar Extraction in Molar-Incisor Malformation: Report of Two Cases

Molar-incisor malformation (MIM) is a newly described dental developmental anomaly that predominantly affects primary second molars, permanent first molars, and, in some cases, permanent central incisors. Diagnosis is usually made upon radiographic examination. The molars usually present with significant cervical constriction, flattened pulp chambers, and absent or thin, short, and narrow roots, whereas the incisors usually exhibit coronal dilaceration. Loss of these compromised teeth in the long term may be inevitable. Thus, clinicians should be aware of this condition and the factors to consider to advise their patients as early as possible. The purpose of this paper is to present two cases of MIM and discuss the factors clinicians should take into consideration to make a care plan in these cases.

The prevalence of three-rooted permanent mandibular molars in a Slovenian population: A radiographic study

Background: Three-rooted permanent mandibular molars (PMMs) have great clinical significance and interesting geographical distribution. Aim: The aim of this retrospective study was to assess their prevalence among a Slovenian dental school patient population. Materials and methods: A total of 3668 PMMs (1361 first, 1573 second, and 734 third) were evaluated by means of intraoral (periapical and bite-wing) radiographs that were collected from dental records of 1317 patients (708 females and 609 males) aged 13-92 years (mean age 37.3 years). The radiographs were evaluated independently by two observers under optimal conditions using a viewing box and a magnifying glass. 95% confidence intervals (CI) for the prevalence of three-rooted PMMs in the population were estimated using Wald's method. The Fisher's exact test was applied to examine any statistically significant difference among PMM groups, between left and right teeth and between male and female patients. Results: Three roots were identified in 1.32% [0.82%-2.10%, 95% CI] of the evaluated first PMMs, 0.25% [0.07%-0.61%, 95% CI] of second, and 1.77% [1.01%-3.04%, 95% CI] of third PMMs. The overall prevalence of three-rooted PMMs was 0.95% [0.68%-1.33%, 95% CI]. The second PMM was less often affected than the first or the third PMM (p < 0.001). No statistically significant differences for three-rooted first, second and third PMMs were detected with respect to sex (p > 0.05) or the side of occurrence (left vs. right side, p > 0.05). Conclusions: A relatively low prevalence of three-rooted PMMs in the examined Slovenian population is in agreement with the available data for Europeans. Three-rooted variants occur least frequently in second PMMs. From a clinical viewpoint, the possibility of three-rooted PMMs should always be considered and looked for, even when treating indigenous European patients.

Salvaging a Periodontally Compromised and Endodontically Involved Three-Rooted Mandibular First Molar With Cervical Enamel Projection

This case report describes the management of a mandibular first molar with an additional distolingual root (radix entomolaris) and grade III cervical enamel projection through a multidisciplinary approach. Diagnosis for the case was endodontic-periodontal lesion due to non-vitality and associated advanced periodontal destruction. The patient was treated with drainage of the periodontal abscess with adjunct antibiotics, phase I periodontal therapy, endodontic therapy, radiculoplasty, regenerative periodontal therapy, replacement of the missing right mandibular second molar, and long-term maintenance. Follow-up of the patient up to 9 months has been uneventful. Cases of advanced periodontal destruction typically show some degree of tooth mobility, which was absent in this case. The article discusses the tripod effect as well as the increased surface area for periodontal attachment provided by the additional root contributing to the non-mobility of the involved tooth.

Taurodontism and its forensic value: a case report

Taurodontism is an anomaly that affects posterior teeth, vertically increasing the size of the pulp chamber, mimicking the shape of bovine teeth, being only evidenced in diagnostic images. This report describes a case of taurodontism in a mandibular second molar, highlighting the forensic importance of this dental anomaly with relevant potential for human identification, not only for its morphological aspect but also for its relatively low frequency in mandibular second molars. In the case under study, the individual did not have any restored teeth. Thus, the set of diverse imaging modalities is fundamental to identify the anatomy of teeth and roots, the only information that could be used in a hypothetical identification situation, assigning to this anomaly an exceptional relevance as a potential characteristic for positive identification.

Analysis of Cause of Endodontic Failure of C-Shaped Root Canals

The purpose of this study was to analyze various characteristics and classification of C-shaped root canals and evaluate the causes of endodontic failure of C-shaped root canals by examining the resected root surface with an endodontic microscope and a scanning electron microscope (SEM). Forty-two teeth with C-shaped root canals were included in this study and had undergone intentional replantation surgery. Before surgery, periapical radiography and cone-beam computed tomography were taken. The root canal configuration was analyzed and classified according to Melton's classification at coronal and apical level. After injection of 1 : 100,000 epinephrine with 2% lidocaine, the tooth was carefully extracted. After the root-end resection, the resected root surface was examined using an operating microscope and SEM. Mandibular second molars were most frequently involved teeth (90.4%). The most frequently observed root canal configurations were C1 at the coronal level (45.2%) and C3 at the apical 3 mm level (45.2%). The most common cause of failure for a C-shaped root canal treatment was a leaky canal (45.2%), followed by an isthmus (23.8%), missing canal, overfilling, and iatrogenic problems. In conclusion, C-shaped root canals were most frequently found in mandibular second molars. The most common cause of failure was a leaky canal and isthmus.

Endodontic Microsurgical Treatment of a Three-rooted Mandibular First Molar with Separate Distolingual Root: Report of One Case

The separate distolingual (DL) roots of three-rooted mandibular first molars are thought to be too difficult for performing apical surgery. This article represents microsurgical treatment of a three-rooted mandibular first molar with a separate DL root. The procedure includes incision and flap retraction, osteotomy, apicoectomy, retropreparation and retrofilling of the root canal, using micro instruments, ultrasonic retrotips and mineral trioxide aggregate (MTA) under a dental operating microscope. Two mm in length of apical root resection, 2 mm in depth of root canal retropreparation with a personalised ultrasonic retrotip, and 2 mm in length of retrofilling with MTA are the key points for accomplishment of apical surgery on separate DL roots. The case was followed up for 15 months after surgery. Clinical and radiographic examinations revealed complete healing of periapical tissue. Separate DL roots of three-rooted mandibular first molars can be treated by endodontic microsurgery with modifications from standard protocol.

Ectopic eruption of a lower permanent molar from the mediaeval necropolis of Alcáçova do Castelo, Mértola, Portugal

The mediaeval necropolis of Alcáçova do Castelo is located in Mértola, Southern Portugal, and dates from the 14th to the 16th centuries. The archaeological campaigns started in 1978 and continue today, having yielded more than 759 graves. This report discusses an ectopic tooth eruption observed in skeleton 535, an adult female individual. A distal right permanent lower molar presents an ectopic eruption at the posterior margin of the coronoid process. On the opposite side, the first and second permanent molars are present, the left permanent lower third molar is absent and the mandibular ramus cannot be evaluated since it is broken off and lost. Tooth migration (heteropia) is a common pathological condition documented in clinical literature. However ectopic eruption of lower distal molars is a rare event, and there are few known cases. This is the first case described in archaeological populations worldwide.

Pyramidal and Taurodont Molars and Their Association With Other Tooth Anomalies

PURPOSE

Determine the prevalence of pyramidal molars (PMs), associated tooth anomalies, and medical conditions (MC).

METHODS

Pantomograms from 10,168 subjects were searched for PMs.

RESULTS

A total of 148 individuals (75.7 percent females), aged 9.7 to 18.9 years old, had PMs. Subjects with MCs (53.4 percent) had on average 17 percent more PMs (P=.0476) and 2.8 times greater odds of palatally displaced canines (P=.0309). The mean number of pyramidal and taurodont molars per subject was 2.9±1.4 (SD) and 3.1±1.7 (SD), respectively. In both sexes, 63.5 percent of all observed PMs were located in the maxilla and 78.5 percent of all PMs were second molars. Taurodont molars increased by 9.4 percent as other tooth anomalies increased by one, but decreased by 8.2 percent for each additional PM. Tooth anomalies associated with PMs were palatally displaced canines (17.6 percent) and short root anomaly of maxillary central incisors (6.1 percent). Delayed eruption was noted in 9.5 percent, tooth agenesis in 6.1 percent, and supernumerary teeth in 3.4 percent.

CONCLUSIONS

The prevalence of pyramidal molars was 1.4 percent, and the female-to-male ratio was 3.1 to one. Pyramidal molars are often associated with medical conditions and other tooth anomalies.

Endodontic management of permanent mandibular molars with 6 root canals: report of 3 cases

Aberrations in the internal dental anatomy present challenges for clinicians performing endodontic therapy. These challenges have been partly resolved in recent years by a more comprehensive knowledge of root canal anatomy as well as advancements in the endodontic armamentarium. The aim of this case series is to describe successful root canal treatment, under magnification, in 3 cases of mandibular first molars with 6 root canals. Two of these teeth had 2 roots (mesial and distal) with 3 canals in each root; the third tooth had 3 root canals located mesially and 3 present distally as well as a radix entomolaris. A distal root with 3 canals is rare; however, it is important to look for such anatomical variations to ensure successful endodontic therapy.

Dens Invaginatus of the Mandibular First Molars in a Dog

A 6-year-old dog was presented for draining tracts associated with both mandibular first molar teeth. Radiographs of the affected teeth showed periapical bone lysis. Surgical tooth extractions were performed and the tooth segments were submitted for histopathologic examination. Microscopic evaluation of the teeth showed in folding of the enamel and dentin consistent with a diagnosis of dens invaginatus. Examination performed 13-months following the extraction procedures indicated uncomplicated healing at the extraction sites and no other visible evidence of endodontic disease.

Association between Molar Incisor Hypomineralization in Schoolchildren and Both Prenatal and Postnatal Factors: A Population-Based Study

BACKGROUND

Although studies throughout the world have investigated potential factors involved in the occurrence of molar incisor hypomineralization (MIH), the findings are varied and inconclusive.

OBJECTIVE

The aim of the present study was to evaluate the prevalence of MIH and identify associated prenatal, perinatal and postnatal factors among Brazilian schoolchildren aged 8 and 9 years.

METHODS

A cross-sectional study was conducted with a randomly selected population-based sample of 1181 schoolchildren. Information on demographic and socioeconomic characteristics as well as prenatal, perinatal and postnatal aspects was obtained through questionnaires. The clinical examination included the investigation of MIH based on the criteria of the European Academy of Paediatric Dentistry. Dental caries in the permanent dentition and developmental defects of enamel (DDE) on the primary second molars were also recorded. Data analysis involved descriptive statistics, bivariate tests and Poisson regression with robust variance.

RESULTS

The prevalence of MIH was 20.4%. MIH was more frequent among children with dental caries in the permanent dentition (PR: 2.67; 95% CI: 1.98-3.61), those with DDE on the primary second molars (PR: 2.54; 95% CI: 1.87-3.45) and those who experienced asthma/bronchitis in the first four years of life (PR: 1.93; 95% CI: 1.45-2.56).

CONCLUSIONS

The prevalence of MIH was high and was associated with dental caries, the presence of DDE on primary second molars and the experience of asthma/bronchitis in early life. These findings could be useful in the identification of children in need of shorter recall intervals to prevent the consequences of MIH, such as enamel breakdown dental caries.

Prevalence and aetiology of Molar-Incisor Hypomineralisation among children aged 8-10 years in Tirana, Albania

AIM

Molar incisor hypomineralisation (MIH) describes the clinical appearance of enamel hypomineralisation of systemic origin affecting one or more permanent first molars (PFMs) that are frequently associated with affected incisors. The aim of this study was to investigate the prevalence and aetiology of MIH in children living in Tirana, Albania.

DESIGN

The study was conducted at the Department of Paediatric and Preventive Dentistry, Faculty of Dental Medicine, and Tirana Dental Public Health Service. A total of 1,575 school children aged 8-10 years were examined by 7 calibrated examiners (dentists) (kappa: 0.86). The Weerheijm criteria were used for the diagnosis of demarcated opacities, post-eruption breakdown, atypical restorations, and extracted PFMs due to MIH.

RESULTS

Prevalence of MIH was found to be 14% (n=227). In the 227 children with MIH, tooth 36 was the most affected PFM, and tooth 46 the least affected. Tooth 21 was the most affected incisor and tooth 32 the least affected incisor by MIH. MIH(+) children had significanly more childhood diseases in the first 3 years of life (p=0.006). Among the children who used antibiotics, MIH(+) cases were 1.41 (1.06-1.87) times higher than in children who did not usedantibiotics, MIH(-) cases.

CONCLUSION

MIH was found to be common among 8-10 year-old Tirana children.

Globodontia in the Otodental Syndrome: A Rare Defect of Tooth Morphology Occurring with Hearing Loss in an Eight-Year-Old

Otodental syndrome is a hereditary disorder comprising globodontia and sensorineural hearing loss. Globodontia is characterized by distinctively bulbous, enlarged crowns of molar and primary canine teeth. Anomalies including taurodontism and hypodontia also occur. We report on the dental treatment and multidisciplinary management of an eight-year-old girl with this rare condition. Referral to Clinical Genetics and Oral Pathology was instrumental in establishing a diagnosis of otodental syndrome for this young patient and her mother, who had similar dental defects. CPD/Clinical Relevance: To increase awareness among practitioners of this rare dental disorder and highlight the need for multidisciplinary management of such cases.

A permanent mandibular second molar with seven root canal systems

This case report illustrates the nonsurgical endodontic management of a seven-canaled mandibular second molar. The root canal configuration presented as four mesial and three distal canals. Identification of the canal system was made with the aid of magnification, ultrasonics, and multiple angulated radiographs. Postoperative examination at 18 months showed a clinically asymptomatic tooth with resolution of the periapical pathology.

Developmental Enamel Defects of the Permanent First Molars and Incisors and Their Association with Dental Caries in the Region of Wielkopolska, Western Poland

PURPOSE

To assess the prevalence of developmental defects of the enamel (DDE) in permanent first molars and incisors and their association with dental caries in two age groups of children living in Wielkopolska, Poland.

MATERIALS AND METHODS

The sample consisted of 225 children ages 6-8 years and 245 children ages 12-14 years (mean age ± SD = 9.9 ± 2.6). Dental defects were described using the modified DDE index. Caries experience was recorded using the DMFT index (number of decayed, missing and filled teeth) for all permanent teeth and for first permanent molars and incisors (DMFT-IM).

RESULTS

Overall, 25.7% of the subjects had at least one permanent first molar or incisor affected by DDE. Diffuse opacity was the most common type of DDE, while hypoplasia was the least prevalent. The mean number of teeth with caries (DT) and the mean number of molars and incisors with caries (DT-IM) were higher in subjects with enamel hypoplasia and/or demarcated opacity than in subjects without DDE or with diffuse opacities (p < 0.05). Caries prevalence was higher in children with hypoplasia and/or demarcated opacity than in subjects without DDE. The differences were statistically significant only for the younger group (p < 0.05).

CONCLUSION

The overall tooth prevalence of DDE in molars and incisors is comparable to that observed in low-fluoride communities. However, a preponderance of diffuse defects suggests the need for further investigation into the aetiology of DDE among Polish children. The results confirm that demarcated opacities and hypoplasia should be considered important caries risk factors.

Rapid Maxillary Expansion without Posterior Anchorage

This work aimed to evaluate an alternative form of maxillary expansion anchored with mini-implants. A patient 12 years, class III in permanent canine teeth, with multiple agenesis of upper posterior teeth was treated with the aid of four mini-implants in the palate and Haas modified type appliance. During the period of expansion, an interincisal diastema was observed as the first clinical sign of disjunction of the sutures. After correction of cross bite, the expansion of the palate was confirmed by upper occlusal radiographs. Thus, the evaluations showed that the technique was effective and that new scientific studies should be conducted to further develop this subject. Keywords: Appliances; Biomechanics; Implants; Malocclusions

Hypophosphatemic Rickets and Pre-eruptive Spontaneous Dental Abscess

The purpose of this report is to describe the diagnosis and dental treatment of a medically complex 14-year-old boy with X-linked hypophosphatemic rickets who presented with a pre-eruptive abscess on a mandibular molar and facial swelling.

Maxillary Nine-year Molars: Prevalence and Associated Dental and Medical Conditions

PURPOSE

The purpose of this study was to determine, from a large number of panoramic images taken in the clinic of a pediatric dentistry residency program, the prevalence of maxillary nine-year molars (9YM), associated medical conditions (MCs), and the presence of coexisting tooth anomalies (TAs).

METHODS

Pantomograms from 13,140 patients were searched for 9YM. Radiographs from identified subjects were examined for coexisting TAs, and charted MCs were noted. For identified 9YM, Nolla's stage of tooth formation was determined and the subjects' dental ages were calculated.

RESULTS

Among 53 subjects (68 percent females), 21 unilateral and 32 bilateral cases of 9YM occurred. Females and males were of similar age (7.98 versus 7.91 years old). Overall dental and chronological ages were significantly different: dental development in bilateral cases was delayed by 4.1 months in females and 2.9 months in both sexes (P=.003). In unilateral cases, it was accelerated by 3.6 months in females and 3.5 months in males. The specific tooth age for all 9YM was 4.95 years for females and 5.56 years for males (P=.018). The average count of associated findings (e.g., missing teeth, peg laterals, other TAs, and other eruption delays) was 0.62 in unilateral and 1.44 in bilateral cases (P=.02). Commonly associated MCs included clefting (<small>N</small> equals five), and Down syndrome (n equals three).

CONCLUSIONS

The prevalence of nine-year molars was one in 248 (0.4 percent), and the average delay in dental development was 2.7 years.

Molar-incisor Malformation: Two Cases of a Newly Described Dental Anomaly

Molar-incisor malformation (MIM) is a recently described dental developmental anomaly with marked manifestations in the primary second molars and permanent first molars and sometimes the permanent maxillary central incisors. To date, there are only two known manuscripts that present this anomaly. The major manifestations are severe coronal cervical constriction of the affected molars and significant under-development of one or more roots. These abnormalities may be detected during routine radiographic examination or present as altered or ectopic eruption or early exfoliation. The characteristic radiographic features are sufficient to identify this abnormality properly. The purpose of this paper is to present two cases of MIM and discuss the impact of the dental abnormalities on patient management.

Predicting Agenesis of the Mandibular Second Premolar from Adjacent Teeth

Early diagnosis of agenesis of the mandibular second premolar (P2) enhances management of the dental arch in the growing child. The aim of this study was to explore the relationship in the development of the mandibular first molar (M1) and first premolar (P1) at early stages of P2 (second premolar). Specifically, we ask if the likelihood of P2 agenesis can be predicted from adjacent developing teeth. We selected archived dental panoramic radiographs with P2 at crown formation stages (N = 212) and calculated the likelihood of P2 at initial mineralisation stage 'Ci' given the tooth stage of adjacent teeth. Our results show that the probability of observing mandibular P2 at initial mineralisation stage 'Ci' decreased as both the adjacent P1 and M1 matured. The modal stage at P2 'Ci' was P1 'Coc' (cusp outline complete) and M1 'Crc' (crown complete). Initial mineralisation of P2 was observed up to P1 'Crc' and M1 stage 'R½' (root half). The chance of observing P2 at least 'Coc' (coalescence of cusps) was considerably greater prior to these threshold stages compared to later stages of P1 and M1. These findings suggest that P2 is highly unlikely to develop if P1 is beyond 'Crc' and M1 is beyond 'R½'.

Microcomputed tomographic evaluation of mandibular molars with single distal canals

The aim of this study was to evaluate, using microcomputed tomography (µCT), the frequency of conjoined mesial canals in first and second mandibular molars with a single distal canal. Mandibular first (n = 114) and second molars (n = 114) with mature apices were randomly selected from a pool of extracted teeth. The specimens were decoronated to establish clinically the existence of a single distal canal. Teeth with C-shaped canals were discarded. Each tooth was scanned with a µCT system and evaluated in 3 dimensions. Of 228 examined teeth, 206 were included in the study. Of these, 129 (62.6%) displayed conjoined mesial canals with a single portal of exit, and 77 (37.4%) displayed 2 distinct mesial canals with 2 separate portals of exit. Of the teeth with conjoined mesial canals, 71 (55.0%) were second molars and 58 (45.0%) were first molars. Conjoined mesial canals exhibited a mean interorifice distance of less than 3.00 mm. These data regarding morphological patterns alert clinicians to the possible need to modify endodontic techniques in mandibular molars with single distal canals.

Evaluation and endodontic management of a patient with 6 single-rooted molars: a case report

This case report describes a patient with unusual tooth morphology involving the bilateral presence of 6 maxillary and mandibular first and second molars with a single root and a single canal. The article also discusses the endodontic management of a single-rooted maxillary molar and the use of cone beam computed tomography for evaluation and diagnosis of these anatomical variations.

Endodontic treatment of mandibular molars with atypical root canal anatomy: reports of 4 cases

The variations in root canal anatomy of multirooted teeth represent a continuous challenge to endodontic diagnosis and treatment. Although the most common configuration of mandibular molars is one containing 2 roots and 3 root canals, there are many different combinations. Very rarely, an additional third (supernumerary) root is seen. When it is located distolingually to the main distal root, this third root is called radix entomolaris (RE), and when it is located mesiobuccally to the mesial root, it is called radix paramolaris (RP). Variations of root canal systems need not always be in the form of extra roots or extra canals. Single roots with single canals can also occur. A general dentist should be aware of these unusual root canal morphologies in mandibular molars for the success of endodontic treatment. These case reports describe the root canal treatment of a case of RE in the mandibular first molar, 2 rare cases of RP (1 each in the mandibular first and second molars), and a mandibular second molar with a single root and root canal.

Human identification using dental techniques: A case report

Dental identification of skeletal remains frequently relies on data comparison. Comparative dental identification is used to establish with a high degree of certainty that the remains of a corpse and a person represented by ante-mortem dental records are the same individual. There is no minimum number of concordant points necessary to perform a positive identification; rather, each case is unique and should be treated as such. In this paper, we present a report of a case in which positive identification was made by a paramolar tubercle in both upper first deciduous molars.

Maxillary first molar with 8 root canals detected by CBCT scanning: a case report

Maxillary molars are prone to exhibit some of the most complex root canal configurations in endodontics. These complexities can result in diagnostic dilemmas, as well as management challenges. This case report illustrates how a cone beam computed tomography (CBCT) scan confirmed an unusual maxillary first molar with 3 root canals each in the mesiobuccal and distobuccal roots and 2 canals in the palatal root. This article illustrates how CBCT scanning and a dental operating microscope can facilitate a better understanding of complex root canal anatomies, ultimately allowing the dentist to clean, shape, and obturate root canal systems more efficiently.

Frequency and anatomy of the retromolar canal - implications for the dental practice

The retromolar canal (RMC) is an anatomical variant of the mandibular canal. Apart from blood vessels it also contains accessory nerve fibers and is clinically important, because its presence can account for failures of mandibular block anesthesias and in rare cases, injuries of its neurovascular bundle can lead to complications such as hemorrhages and dysesthesias. The aim of this retrospective case study was to analyze the frequency and anatomy of the RMC using cone beam computed tomography (CBCT) in order to draw conclusions for the dental practice. A total of 680 CBCT scans comprising 1,340 mandibular sides were evaluated. A total of 216 RMCs (16.12%) were found. The most common appearance of the canal (39.82%) corresponded to type Al (vertical course), whereas type C (horizontal course) occurred least often (6.02%). Mean measured values were 1.03 mm (SD=0.27mm) regarding the RMC diameter, 10.19 mm (SD=2.64mm) regarding the RMC height and 15.10 mm (SD=2.83 mm) regarding the distance of the RMC to the second molar. Neither demographic factors nor the spatial resolution of the CBCT had a statistically significant impact on the frequency of the RMC. Since the present study revealed a frequency of RMCs amounting to 16.12% (corresponding approximately to every sixth retromolar area), we recommend to spare it during surgery or to consider an additional locoregional anesthesia in the retromolar region. For preoperative diagnosis the CBCT has proved suitable, offering the possibility to select the spatial resolution depending on the indication, so that radiation exposure is reduced without a decrease in validity.

Molar incisor hypomineralization and dental caries in six- to seven-year-old Thai children

PURPOSE

This study aimed to determine the prevalence of molar incisor hypomineralization (MIH) in Thai children and evaluate the association between MIH and dental caries in the permanent dentition.

METHODS

A cross-sectional study was conducted among six- to seven-year-old participants of a birth cohort study in Khon Kaen, Thailand. MIH was examined by one calibrated dentist using European Academy of Pediatric Dentistry criteria. The association between MIH and caries was determined by logistic regression at subject level, and generalized estimating equations at tooth level.

RESULTS

Of 484 children who had at least one erupted permanent first molar, the prevalence of MIH was 20 percent, with no difference between genders. Children with MIH had increased odds of having caries in the permanent dentition compared to those without MIH (odds ratio [OR] equals 4.6; 95 percent confidence interval [CI] equals 2.7 to 7.9). MIH molars had approximately 10 times higher odds of developing caries than non-MIH counterparts (OR equals 9.9; 95 percent CI equals 5.7 to 16.9). Caries risk was higher in the upper molars than in the lower molars.

CONCLUSIONS

Molar incisor hypomineralization is common and associated with increased risk for dental caries among this group of Thai children.

Radix Entomolaris - a rare case series

INTRODUCTION

The success of root canal treatment is determined by satisfying the basic principles of complete removal of the endodontic pathology through chemo-mechanical cleansing of the root canals followed by shaping and then by obturation to provide the ideal hermetic seal. To achieve such success a thorough knowledge of the root canal anatomy is a basic requirement. Several anatomic variations of the mandibular molars have been reported among which is the reportedly rare Radix Entomolaris(RE), a mandibular molar with an additional root located lingually.

AIMS AND OBJECTIVES

To present five cases of RE diagnosed pre-operatively using radiographs and subsequently successfully endodontically treated. We also aim to highlight the considerations for the diagnosis and management of RE in general dental practice.

CONCLUSION

Even though RE is rarely encountered in general dental practice, the possibility that it may occur warrants the need to have sufficient knowledge regarding diagnosis and the appropriate modifications in endodontic management of these teeth. Preparedness coupled with a carefully modified clinical approach aids in successful management of RE and ensures that these cases could be handled with ease.

Mandibular first molar with six root canals: a rare entity

Recently, there has been an ongoing trend of case reports that highlight the presence of more than four root canals in mandibular first molars. This tendency warns clinicians to be more prudent when dealing with mandibular first molars requiring endodontic treatment. Moreover, radiographic examination should be taken as a clue providing tool rather than as an absolute guide to anatomy and its associated aberrances. This case reports the successful non-surgical endodontic management of a mandibular first molar with six root canal systems with three canals in the mesial root and three in the distal root. The classification of root canal systems found in this case was Sert and Bayirli type XV in both the roots. After non-surgical endodontic treatment, the tooth was restored definitively with a resin composite core followed by porcelain fused to the metal crown. This case adds to the library of previously reported cases of mandibular first molars with six root canals and further emphasises on the importance of rare morphological deviations that may occur in the mandibular first molars.

Concrescence: assessment of case by periapical radiography, cone beam computed tomography and micro-computed tomography

The aim of this article was to describe imaging aspects of concrescence analyzed by three imaging modalities. A second molar joined together with a third molar was imaged using digital periapical radiography, cone beam computed tomography (CBCT) and micro-computed tomography (Micro-CT). On periapical radiograph, the mesial root of the third molar is superimposed on the distal root of the second molar. On CBCT images, a large cementum union between bulbous roots was detected, confirming the diagnosis of concrescence. On micro-CT images, the cementum union appeared limited to the apical third of the roots. In conclusion, both computed tomography modalities allowed for the diagnosis of concrescence. However, only micro-CT provided the real extension of the cementum union.

Radix entomolaris: 2 case reports and clinical guidelines for endodontic management

Variations in dental anatomy and root canal systems are often reported in the dental literature. Among them, Radix entomolaris (RE) is the presence of an additional lingual root in mandibular molars. Though RE appears relatively infrequently, knowledge of the condition will aid in its management. This article presents 2 case reports of RE and clinical guidelines for endodontic management.

Henry Moon and his molars

Henry Moon qualified in London in medicine and dentistry, emigrated to New Zealand, eventually returning to London. He is known for his observations of the malformation of tooth cusps in children with congenital syphilis.

Regional odontodysplasia: literature review and report of an unusual case located in the mandible

The purpose of this report was to describe the clinical, radiological, and histopathological features of a case of regional odonto- dysplasia (RA) in a seven-year-old boy who was followed for approximately two years. The case is unusual in that the dysplasia occurred in the mandible, and there was a normal-appearing tooth within the lesion, suggesting that there may be local factors that determine susceptibility of individual teeth in RA. The diagnosis of RA was based on the typical features of "ghost" teeth and evidence of disrupted calcification characterized by psammomatous bodies, hypomineralization of enamel, and the presence of interglobular dentin. Sequential orthopantomograms provide evidence of delayed dental development.

[Analysis of dental agenesis patterns of the oligodontia patients using the method of tooth agenesis code]

OBJECTIVE

To analyze the common dental agenesis patterns of the oligodontia patients.

METHODS

The information of 64 oligodontia patients was collected, including the histories, oral examinations and panoramic radiographs. The Tooth Agenesis Code (TAC) procedure was used to analyze the agenesis pattern of each quadrant.

RESULTS

In the maxilla, 63% (40/64) (right side) and 58% (37/64) (left side) could be described using eight different patterns. The most common pattern was agenesis of the maxillary lateral incisor, canine and both premolars.In the mandible, 52% (33/64) (right side) and 53% (34/64) (left side) of the patients could be described using only five different patterns, the most common pattern was agenesis of both mandibular premolars.

CONCLUSIONS

Common patterns of tooth agenesis were successfully identified in non-syndromic oligodontia patients.

Inter-relations between infraocclusion of primary mandibular molars, tipping of adjacent teeth, and alveolar bone height

PURPOSE

The purpose of this study was to examine inter-relations between infraocclusion of primary mandibular molars, tipping of adjacent teeth, and alveolar bone height of infraoccluded teeth.

METHODS

A total of 402 periapical radiographs of infraoccluded primary mandibular molars were reviewed. Infraocclusion, alveolar bone height, and tipping of adjacent teeth were measured.

RESULTS

Infraocclusion was most prevalent among primary mandibular first molars. The amount of infraocclusion was most profound among primary mandibular second molars (2.79±1.25). The shortest distal alveolar crest (reflected by the highest distance between the cementoenamel junction and bone crest) was observed among infraoccluded primary mandibular first molars (0.9±0.92). The permanent mandibular first molar and the primary mandibular first molar demonstrated the maximum tipping mesially and distally.

CONCLUSIONS

Infraocclusion of primary mandibular molars, tipping of adjacent teeth, and alveolar bone height of the infraoccluded teeth are inter-related.

Taurodontism in deciduous molars

Taurodont teeth are characterised by large pulp chambers at the expense of roots. An enlarged pulp chamber, apical displacement of the pulpal floor and no constriction at the level of the cement-enamel junction are the characteristic features of taurodont tooth. It appears more frequently as an isolated anomaly but its association with syndromes and other abnormalities have also been reported. Permanent dentition is more commonly affected than deciduous dentition. This paper presents a case report of taurodontism in relation to mandibular deciduous second molars.

Aberration in the palatal root of the maxillary first molar

Thorough knowledge of root canal morphology is essential for the endodontic therapy. Variations in the root and root canal morphology, especially in multirooted teeth, are a constant challenge for diagnosis and management. The dentist needs to be familiar with the various root canal configurations and their variations for successful endodontic therapy. There are rare variations in canal number and configuration in maxillary molars, which could affect treatment outcome. Two lingual root structures are occasionally found on human permanent maxillary molars. One of these is the normal lingual root, which is always present, the other is a supernumerary structure which can be located either mesiolingually (radix mesiolingualis) or distolingually (radix distolingualis). The purpose of this paper is to review the literature and to demonstrate a case report which describes the successful non-surgical endodontic management of an unusual maxillary first molar with four separate roots and four canals.

Missed canal systems are the most likely basis for endodontic retreatment of molars

Unfortunately, a small percentage of endodontically treated teeth do not respond favorably to non-surgical root canal treatment. Failure to cate and treat an additional nal system is cited as the principle basis for endodontic retreatment. The aim of this retrospective clinical study was to identify the incidence of additional or missed canal systems in molar retreatment cases in a private practice setting. Missed canals were identified in 64 of the 133 previously treated teeth (48%). Of the total missed canals, 11% involved a maxillary second molar and 44% involved a maxillary first molar. For the maxillary first molars, 93% of all missed canal were identified in the mesiobuccal root. In the mandibular second molars, 29% of missed canals were identified in the distal and 71% were identified in the mesial root. In the mandibular first molars, 86% of missed canals were identified in the distal and 14% were identified in the mesial root. The results of the current study support the findings of previous studies and confirm the importance of locating, instrumenting and obturating the endodontic treatment. Given that failure to locate all canal systems of a tooth contributes significantly to unsuccessful endodontic treatment, all measures available to the clinician to maximize canal identification should be used.

Nonsyndromic tooth agenesis patterns and associated developmental dental anomalies: a literature review with radiographic illustrations

Tooth agenesis is one of the most intriguing phenomena, because it is frequently associated with other oral anomalies, structural variations and malformations of other teeth, late eruption, transposition and crowding. The diagnosis can be quite challenging as radiographic examination is critical for the diagnosis but not always possible and the late developing teeth may be sometimes scored developmentally missing. Accurate diagnosis therefore requires radiographic, clinical, and dental cast examinations. It is an important clinical and public health problem. Patients with missing permanent teeth may suffer from a reduced chewing ability, inarticulate pronunciation, and an unfavorable aesthetic appearance. Clinically, early diagnosis of a dental anomaly can alert the clinician to the possible development of other associated dental anomalies in the same patient or family, and avoid the possible sequelae. Understanding of tooth agenesis patterns and their impact on diagnosis, prevention, and eventually therapeutics are becoming integral parts of comprehensive dental care. Dental examination with radiographic screening of hypodontia in early childhood should be emphasized as part of public oral health policy to allow early diagnosis and timely intervention.

Endodontic treatments of mandibular first molar with middle mesial canal: two case reports

The mandibular first molars mostly have two mesial canals. In this report, two cases of mandibular first molars with three mesial canals are presented. The middle mesial canal was detected under endodontic microscope and further confirmed by cone-beam computed tomography and angled radiography, respectively. The purpose of this paper was to highlight the possibility of an aberrant root canal in a mandibular first molar and to help reduce the failure rates of the dental pulp treatment of the mandibular first molar.

Maxillary first molar with three buccal roots evaluated with cone-beam computed tomography: a rare case report

This case report describes the nonsurgical endodontic management of a maxillary first molar with the unusual morphology of three separate buccal roots. An accurate assessment of this morphology was made with the help of cone-beam computed tomography (CBCT). This report also describes the varied root morphology associated with maxillary first molars and the role of CBCT as a diagnostic tool for managing these complex cases successfully.

Maxillary molar with two palatal canals

The endodontic treatment of maxillary molar with an aberrant root canal morphology can be diagnostically and technically challenging.1 Unusual root canal morphology in multirooted teeth is a constant challenge for diagnosis and successful endodontic treatment. Presence of extra canals, lateral canals, deltas is commonly encountered.2 This case report is presented to illustrate and describe the endodontic treatment of maxillary first molar with an unusual morphological variation of palatal root. The palatal root had two canals that appeared to unite in the apical third of the canal.

Prevalence of taurodontism in primary mandibular first molars of ethnic Indian children

The objective of this study was to determine the prevalence of taurodontism in primary mandibular first molars in ethnic Indian children using periapical radiographs. Periapical radiographs of 274 children obtained from December 2008 to August 2010 were retrospectively screened and examined. Radiographs of 196 patients (99 boys and 97 girls; ages 2.5-10.5) with bilateral primary mandibular first molars were randomly selected and evaluated. The gender, symmetry, and frequencies of occurrence of taurodont primary mandibular first molars were compared and the obtained data were statistically analyzed using the x2 test. Eight (4.08%) taurodont primary mandibular first molars were found with a bilateral incidence of a symmetrical distribution of 38% (3/8). The prevalence of taurodontism in primary mandibular first molars did not differ significantly between right and left sides or with gender (P ≥ 0.05). The results of the present study indicate that approximately 4% of Indian children had taurodontism in primary mandibular first molars. Clinicians should be aware of the prevalence of this anatomic variant in primary mandibular first molars among the Indian population for early identification of taurodonts and for rendering the best care during dental treatment.

Macrodontia, shovel-shaped incisors, and multituberculism: probable Ekman-Westborg-Julin trait

Multiple macrodontia is a rare finding and is defined as a condition in which a tooth is significantly larger than normal. Macrodontia may occur as an isolated finding, part of a group of dental anomalies, or as a component of a syndrome with multiple oral and systemic manifestations. The purpose of this paper was to report a case of macrodontia affecting all permanent teeth and exhibiting shovel-shaped maxillary and mandibular incisors and multituberculate molars and premolars. Some or all of this patient's characteristics have been reported in both males and females, with a ratio of 5:2. No inheritance pattern has been established, as these traits have generally occurred spontaneously. As more individuals are identified and as molecular techniques continue to advance, it is probable that a gene or genes responsible for macrodontia and the associated traits will be identified.