Fourth Molar Research Articles

Non-syndromic supernumerary fourth molar: A report of two cases and review of literature

Background: Supernumerary teeth are excess teeth found in a normal dentition, with a prevalence of 0.1‒3.8% in the permanent dentition and 0.3‒0.6% in the primary dentition. This case series presents two non-syndromic supernumerary fourth molar cases in two male and female patients. Case Report: This study describes two rare supernumerary fourth molar cases. Both cases were asymptomatic and impacted in the maxillary arch. A routine panoramic radiograph revealed the presence of them for the first time. The medical and familial records of the patients were non-contributory, with no abnormalities in the extraoral examination. Conclusion: Well-developed, impacted supernumerary teeth are rare occurrences in individuals with no concurrent diseases or syndromes. Dental practitioners should know the different types of supernumerary teeth and manage them according to their type and possible complications.

A rare case of impacted mandibular distomolar: Identification and management at a remote high altitude location

Planning the surgical extraction of an impacted supernumerary tooth poses a very peculiar problem for a dental professional. The management of this unique clinical situation is quite challenging and requires meticulous preparation, especially in a remote high altitude regions. Supernumerary teeth are those which are present in excess of the normal permanent or deciduous dentition in the oral cavity. A distomolar, also commonly known as the fourth molar, is a supernumerary tooth located distal to the third molars. The occurrence of supernumerary teeth is much more frequently observed in the maxillary arch as compared to the mandible. While the distomolar is quite infrequently observed, its occurrence in the mandible is even rarer. In this article, we present an overview of distomolars along with a case report on the management of a symptomatic mandibular distomolar at a remote setup in Tangtse region of the Union Territory of Ladakh.

Concomitant Existence of Tooth Agenesis (Agenesis of Four Second Premolars) and Supernumerary Tooth (Dens Distomolar)-Report of a Rarest Case

“Distomolar” is also called as ‘fourth molar’ is the supernumerary tooth occurring distal to the third molar. Occurrence of distomolar is a rare phenomenon. Along with this condition congenital agenesis which is a contrast phenomenon compared to extra teeth is still a rarer entity. Therefore, the aim of this paper is to present occurrence of fourth molar in the mandibular arch and congenital agenesis of all second premolars (four premolars) involving both maxillary and mandibular quadrant in a non-syndromic Indian female patient. Such combination of two different anomalies representing two different dental phenomenon is not reported till date according to author’s best of knowledge.

FAMILIAL FOURTH MOLARS IN NON-SYNDROMIC PATIENTS: CASE REPORT OF AN UNUSUAL ENTITY

Objectives: This work aims to report an unusual case of fourth molars in three patients from the same family. Case Report: The patient underwent third and fourth molars removal with little morbidity. Some important aspects were discussed, in particular the use of piezosurgery. Important features of the classification and epidemiology of distomolars and paramolars were discussed. The authors believe this to be the first report of familial fourth molars. Conclusions: Although considered a rare condition, fourth molars can be treated as an unusual or uncommon condition. The term rare is not appropriate to this situation and the authors debate it. Piezosurgery is very harmful in extensive osteotomies to remove third and/or fourth molars.

Fusion of an Impacted Third and Supernumerary Fourth Molar Tooth with Concrescence of the Second Molar

We report the case of a symptomatic 41-year-old female presenting with fusion of an impacted third (LL8) and fourth (LL9) mandibular molar tooth with concrescence of the second molar tooth (LL7). Cone-beam computed tomography showed direct contact with the inferior dental nerve (IDN) and lingual aspect of the double tooth. The patient underwent surgical removal of the LL8–LL9 using piezoelectric surgery. We present the first case of successfully using pre-operative CBCT in the planning of surgery and piezoelectric surgery to separate an impacted fused LL8–LL9 from a concrescent LL7 without causing trauma to the LL7 or intimately positioned IDN. CPD/Clinical Relevance: An impacted fused mandibular third and supernumerary fourth molar with concrescence of the second molar requires very careful management.

A new Early–Middle Miocene phalangerid (Marsupialia: Phalangeridae) from the Riversleigh World Heritage Area, Boodjamulla (Lawn Hill) National Park, northwestern Queensland

Archerus johntoniae represents a new genus and species of phalangerid possum from the Early to Middle Miocene of the Riversleigh World Heritage Area, northwestern Queensland. The new taxon is the tenth extinct phalangerid species to be described and is the seventh species recognized from the diverse Riversleigh fossil assemblages. A. johntoniae has its closest morphometric affinities (such as relatively short molars, narrow premolars, an anteriorly narrow upper first molar, and posteriorly narrow fourth molars) with trichosurine and stem phalangerids. Morphologically, A. johntoniae has similarities to phalangerines and trichosurines, but is most dissimilar to other fossil phalangerids. The new species is one of the smallest (ca 1.3 kg) phalangerids known and may have occupied Early and Middle Miocene frugivorous/insectivorous niches demarcated from other phalangerids by body size and diet. A. johntoniae is one of a minority of Riversleigh species to have survived a significant decline in marsupial diversity associated with a rapid spike in global temperature at the Middle Miocene Climatic Optimum.Troy Myers [t.myers@unsw.edu.au], Earth and Sustainability Science Research Centre, School of Biological, Earth & Environmental Sciences, UNSW Sydney, NSW 2052, Australia; Kirsten Crosby [Kirsten.crosby@gmail.com], GHD Group Pty Ltd, Level 15, 133 Castlereagh St, Sydney, NSW, 2000 (currently), School of Biological, Earth & Environmental Sciences, UNSW Sydney, NSW 2052, Australia.

A case report of multiple supernumerary teeth: Post-permanant dentiton or hyperactivity of dental lamina

Supplementary teeth in simple terms could be be defined as those supernumerary teeth which are well aligned in the arch resembling the normal anatomical structures of teeth. There has been evidences of supplementary premolars and molars since from beginning of the civilization. According to Darwin’s theory of evolution which stated that during the course of humans evolution the organs which do not have greater use in regular became vestigial which included the appendix, tail bone, fourth molar. Supernumerary teeth often remain asymptomatic, and only get diagnosed incidentally during a routine dental visit on radiographs. Nevertheless, various complications have been reported in literature related to supernumerary teeth such as disturbed eruption, malpositioning or rotation, root resorption of neighbouring teeth, and development of dentigerous cysts in impacted supernumeraries. Root resorption of neighbouring teeth can be radiographically diagnosed in up to 22.8% of the cases. Here we report an unusual case of multiple supernumerary teeth in a non-syndromic patient of African native.

Hyperdontia across sub-Saharan Africa: Prevalence, patterning, and implications

ObjectiveHyperdontia data in modern and premodern sub-Saharan Africans are presented by region—West, Central, East, and South, and sex. Beyond describing the anomaly, comparisons are made with other world populations and future work is promoted. These findings may be useful to both dental clinicians and anthropologists. MethodsHyperdontia presence and patterning were recorded in 51 samples of skeletal dentitions and hardstone casts (n = 1916). Its infrequency prompted regional pooling after grouping by time. Only adults were included to record later forming fourth molars reportedly common in Africans. Quantitative analyses, including 95% confidence intervals, were conducted to characterize spatiotemporally sub-Saharan peoples. ResultsForty-four of 1429 modern individuals (3.08%) exhibit hyperdontia (CI 2.24–4.13%). Regional variation is significant, particularly West-Central vs. East-South, between 6.8% and 1.5%. Four of 487 premodern individuals, 0.82%, have hyperdontia (0.22–2.10%), with minimal regional differences. Males are most affected, as reported by other researchers. Other similarities with non-African research are evident regarding isomere, antimere, and form, with one key exception—a proclivity for the posterior over anterior maxilla. Conclusions3.08% is toward the upper end of published world ranges, including an oft-cited 0.1–3.6 + %. However, the regional variation argues against a single prevalence to describe collectively the subcontinental inhabitants. This variation parallels past west to east and south migrations like other biocultural indicators. Thus, beyond a health concern to clinicians or interesting anomaly to anthropologists, hyperdontia may be useful in other studies. There are no equivalent premodern ranges for comparison. Similarity in patterning overall to previous findings suggests a shared, potentially ancient genetic component in expression.

Similar forms have similar functions: dental microwear variability in Tasmanian devils

Abstract Dental microwear texture analysis (DMTA) is commonly used to assess the dietary ecology of modern and fossil taxa. In carnivorans, teeth with different functions record dietary behavior differently. Here, we assess DMTA variability along the tooth row of an extant carnivorous marsupial—the Tasmanian devil, Sarcophilus harrisii—which has multiple carnassial-like molars that may function and record diet similarly. We compared the complexity (Asfc), anisotropy (epLsar), and textural fill volume (Tfv) of the lower second, third, and fourth molars of Tasmanian devils to test the hypothesis that teeth with similar forms yield similar functions. Although third molars do have significantly higher epLsar values than fourth molars, all other DMTA attributes are indistinguishable from one another. These data suggest that teeth with comparable morphologies in the same taxon have similar functions and largely record diet similarly. In addition, we compared fossil and modern specimens of S. harrisii from Tasmania to assess dietary behavior over time. These analyses indicate that foods with similar textures have been consumed since the late Quaternary.

The Occurrence of Fifth and Additional Molars

The purpose of the study was to summarize the current knowledge available of fifth and additional molars, including their epidemiology, demographics of subjects and management strategies. Additionally, directions for further research are formulated. Materials and methods. The Medline database (through PubMed) and Web of Science Core Collection were searched using the following keywords: “Supernumerary molar*”, “Additional molar*”, “Fifth molar”, “Five molar*”, “Sixth molar*”, “Six molar*”, “Seventh molar” and “Seven molar*”. Additionally, the search engine Google was used using the same keywords. Moreover, the references of the literature identified using the previous methods were searched for other eligible publications. Publications were included if they described at least one fifth or additional molar in a human subject; reported on anatomical, epidemiological, demographic or clinical aspects or the full text could be sourced. Results and discussion. Fifth and additional molars have been sporadically described in literature, which is summarized in the current review. The age at detection of supernumerary molars ranged from 12 to 33 years (average: 21.8 years). When molars are present beyond a fourth, it usually only concerns fifth molars. Only one case of sixth and seventh molars was identified. Like fourth molars, they occur usually in the maxilla and unilaterally. Most of the reports did not mention any specific symptoms regarding these supernumerary molars. They were usually managed by removal or not at all. Six case reports reporting on fifth and additional supernumerary molars were included. An additional case series was identified that included three cases of a patient with fifth molars. Only two of the identified publications were published after 2010, while two were published before 1980. No prospective studies studying the entities were identified. It is clear that the body of evidence about supernumerary molars beyond a fourth is very limited in size. Additionally, the available literature is lacking both in internal and external validity. Conclusion. The body of evidence about fifth and additional molars is very sparce, with only a few case reports having been published. It is however clear that these entities are very rare and share several characteristics with fourth molars. Importantly, it seems that they are often asymptomatic and do not always require dedicated treatment. Further research is needed to better understand the epidemiology of these entities

CASE REPORT: THE FORTH MAXILLARY MOLARS IN WOMAN LIVING IN THE IV CENTURY A.D.

Supernumerary teeth in humans are considered as those in addition to the normal series of deciduous or permanent dentition. Distomolars or the forth molars that erupt behind wisdom teeth are found in 0,18–3,8% of the modern population, but are quite rare compared to other supernumerary teeth. Odontologic studies of ancient and contemporary populations allow not only evaluate health state, life style and diet of people, but explain etiology, clinic manifestations and treatment of dentomaxillary abnormalities. The forth molars mostly are mostly described in people over the period of the XIX-XXІ centuries and only few researchers presented this variant in ancient people.
 The aim of the study was to estimate a case of supernumerary teeth in human remains, which represented by Chernyachov archarological culture artefacts. Sex and death age were established by methods widely accepted in anthropology. The method of analysis of dento-maxillary region developed by the authors and orthopantomography were used for dental examination.
 An undamaged skeleton was found during archaeologic expedition nearby the town of Shyshaki, Poltava region (burial No 112) in 2016 and now are kept at Archaeological Site Preservation and Research Centre (Poltava). Archaeologists defined the remains dated by the end of the IV c. AD. The skeleton belonged to 1820 years` women was in a good state; no pathological changes of the skeleton were found. Maxilla of the skeleton had supernumerary forth molar (tooth 19) and alveolar sockets of teeth 13, 12, 21, 22, 25, 27, 28 and 29 recorded as being lost anteand postmortem. Teeth presented neither enamel hypoplasia nor tooth wear. Root of tooth 19 was immature.
 Etiology of supernumerary teeth is still unclear yet, but there are no data supporting atavistic theory. Bilateral distomolars could be a symptom of systemic abnormalities of dentofacial region, but the skeleton studied had no pathological changes, so this abnormality could not be characterized as systemic. Supernumerary teeth could be described as a congenital anomaly associated with chromosome, autosome or dominant transmission, but the authors do not have enough evidence to prove such nature of this anomaly. This studied case is more likely related to the theory of hyperactivity of dental lamina during follicle development that dominates nowadays.
 According to morphological classification, supernumerary teeth in our case are of premolar shape.
 Сlinical manifestations of distomolars can be different. Distomolars can be asymptomatic and rarely found erupted; they may provoke no problems or hurt buccal mucosa. Also a retained distomolar may cause retention and pericoronaritis of the third molar, development of keratoand paradental cysts, localized periodontitis, decompression of lower alveolar nerve, or manifests itself in jaw fracture. Oral signs of retained distomolar are mobility of the third molar, discomfort feeling in retromolar area, bulging of mandible. Supernumery and retained teeth are mostly found by X-ray examinations usually taken for non-related dental problems. The distomolars investigated were retained and the mosy likely caused no problems.
 Basic methods of the treatment of the fourth molars are extraction and observation, however, choice of the treatment method depends on clinical manifestations and estimation of individual risk factors.
 Supernumerary retained fourth molars in the studied woman are non-systemic distomolars with premolar shape. Taking into account that most of the fourth molars are detected by X-ray examination, dentists should be careful not to miss this abnormality.

A Case Report of Kissing Molars Class III

Kissing molars (KMs), first reported by Van Hoof in 1973, refer to molars with occlusal surfaces that contact each other in a single follicular space while their roots extend in opposite directions. This is a case of a 20-year-old male who presented with complaints of right mandibular molar pain with cold water contact and occlusion. Panoramic and cone-beam computed tomography (CBCT) images revealed impaction of the right mandibular third and fourth molars, with the occlusal surfaces contacting each other while the roots extended in opposite directions. KMs are classified according to the impaction of the mandibular first and second molars (Class I), second and third molars (Class II), and third and fourth molars (Class III). Our patient was considered Class III. Given the patient’s preference for surgical treatment, successful teeth extraction and extirpation were performed under intravenous sedation. The patient’s postoperative course was unremarkable. We describe a case of KMs Class III with a cystic variant assessed by panoramic and CBCT images. We additionally review all KMs Class III reported in the literature.

Patient satisfaction with root canal treatment and outcomes in the Swedish public dental health service. A prospective cohort study.

To document satisfaction with root canal treatment procedures and outcomes among patients treated at Swedish public dental clinics. The original material comprised 243 patients who began root canal treatment (RCT) at 20 public dental clinics in the county of Västra Götaland, Sweden. One to three years later, 236 (97.1%) were posted a questionnaire of eight items, rating patient perceptions of RCT-completion, present pain intensity and satisfaction with the RCT. To evaluate the reliability of the original responses, the first 50 respondents were mailed a follow-up questionnaire. Both descriptive and analytical statistics were used to compare respondents and non-respondents and tooth groups. One hundred and fifty-nine patients (67.4%) responded: 86 (54.1%) women and 73 (45.9%) men. The mean age 52.5 years, was higher than for non-respondents (P<0.001). A completed root filling was registered for the majority of the teeth (n = 112, 70.9%), but significantly fewer molars had been completed (n = 46, 59.7%, P = 0.02). Fifty percent (n = 59) of the patients reported current pain, mostly mild in intensity (n = 45, 38.1%). One hundred and twenty-three patients (80.9%) recalled experiencing pain during RCT. The highest satisfaction was registered for the item 'chewing ability' (mean = 1.6, SD = 1.9). The majority of patients (n = 114, 75.0%) stated that in retrospect they would still have chosen RCT. However, these patients belonged to the group which either registered the tooth as still present, or had not experienced much discomfort during or after RCT. Forty-four patients (88.0%) responded to the second questionnaire. The reliability of the responses was good. In summary, one to 3 years after beginning RCT at a public dental clinic, patient satisfaction was high, even though every fourth molar had been extracted or treatment had not been completed and half the patients reported persistent pain. The reliability of the patients' responses was considered to be good. The results indicate a need for further clinical observational studies of RCTs undertaken in general dental practice, with special reference to patient-centred outcomes.

Morphology Analysis of Human Fourth Molars Using Computed Microtomography - Pilot Study

Analyze the morphological characteristics of fourth molars from non-syndromic patients using computed microtomography (microCT). Five human fourth molars (case group) and other three third molars (control group) were obtain from Biobank of UFPR Dentistry School. The teeth were submitted to macroscopic and microCT analysis. Sample characteristics: 60% of the teeth from the lower arch, mainly from the right lower arch (40%). The results showed that eighty percent of the teeth were impacted and all of them presented normal morphology. The microCT revealed that one of the fourth molars had hypercementosis. Concerning the root canal anatomy, all of the fourth molars studied had just one principal root canal. Four teeth had one collateral canal that ended at the lateral face of the root. The volume average of root canal, dentine and enamel were respectively 9.27 mm3, 122.64 mm3 and 74.71 mm3. The averages between these variables in third molars were 46.98 mm3, 473.25 mm3 and 198.34 mm3, respectively. Proportionally, the volume of the fourth molars was five times less than the third molars, but the dentine and enamel volume were, respectively, 3.8 and 2.7 times less than third molars. The fourth molar teeth usually showed only one principal root canal and it can be associated with other alterations, such as hypercementosis. Although the fourth molars were smaller, the proportion of enamel volume is bigger than third molar in comparison.

Prevalence of hyperdontia, hypodontia, and concomitant hypo-hyperdontia

Background/purposeAnomalies in human dentition are some of the most common occurrences of congenital abnormalities. Present study aimed to determine the prevalence of hypodontia, hyperdontia and concomitant hypo-hyperdontia (CHH) among patients attending the University of Nevada, Las Vegas (UNLV) School of Dental Medicine clinics. Materials and methodsRetrospective search was conducted on patients’ clinical notes in AxiUm™. Search included using keywords such as “hypodontia”, “hyperdontia”, “supernumerary teeth” and “congenitally missing”. Panoramic radiographs were used to confirm the hyperdontia, hypodontia or CHH for patients attending the UNLV SDM clinics from 2010 to 2018. Collected data were analyzed using the chi-square test. Results1101 patients were populated using the keywords. From these populated patients, 186 had hyperdontia, 23 hypodontia, and 3 presented with CHH. The distribution of males and females was 54.7% and 45.3% respectively. Hispanics, African Americans, Asians, Caucasians and ethnically unspecified patients represented 43.39%, 14.25%, 3.30%, 8.02%, and 31.13%, respectively, of those patients with a dental anomaly. Hyperdontia was most common amongst Hispanic patients with 39.24%, followed by the unspecified patients at 32.8% as well as amongst males at 56.45% (P value of 0.03). Unidentifiable supplemental teeth were overall the greatest in number with the lower right premolars, tooth 44, being the most common. This was demonstrated in the Hispanic patients whereas within the African American patients a 4th molar was in excess. ConclusionHispanic patient population has a significant link to dental anomalies, specifically hyperdontia while the presence of the fourth molar was prominent among African American patients.

Topographic changes in NiTi rotary instruments after the clinical use.

Surface alterations of instruments were investigated after single and multiple uses in the root canals. XP-endo Shaper (n=5) and WaveOne GOLD (n=5) files were used until the separation of the instruments occurred. The apical 3-mm and separated fragments were analysed by SEM to determine the changes in the instruments and the cross-sections of the separated fragments. Each group was divided into five subgroups: control, first, second, third and fourth molar. The results were reported descriptively for each group. In the XP-endo Shaper group, microcracks started to appear after the second use, and pitting and galvanic corrosion occurred after the third use. During the fourth use, microcracks propagated, resulting in ductile fracture while it happened after the third use in the second group. The single use of XP-endo Shaper and WaveOne GOLD was safe without any major changes on their surfaces. Reciprocating motion was not necessarily superior to full rotation motion.

Distomolars – Exploring the known entity

A supernumerary tooth is one that is additional to the normal series and can be found in any region of the dental arch. A distomolar, also called as “fourth molars,” is a supernumerary tooth that is positioned distal to third molars. Distomolar can be found completely erupted in the dental arch, or it could be partially or entirely impacted. This literature review attempts to highlight the prevalence, etiology, morphology, complications, and diagnosis of distomolars. Various literatures reveal that supernumerary teeth are more frequently seen in the maxilla with a male predilection and their prevalence in the permanent dentition has been approximated to range from 0.1% to 3.6%. A distomolar may have a normal morphology or have a much smaller dimension than adjacent third molars. Molariform (tuberculated) shape is most frequently observed by various authors in their studies. Distomolars are usually found impacted within the jaws and may lead to several complications. Even though the frequency of distomolars is low, dental surgeons should always be aware of the presence of distomolars during radiographic or clinical examinations. A thorough knowledge and information about this supernumerary entity may definitely provide a hope for an early detection and appropriated treatment planning so as to prevent or minimize any complications created by them.

A rare case of a maxillary fourth molar: Case report

Introduction: The objective of this clinical case report is to describe the presence of bilateral fourth molars. The occurrence of supernumerary teeth (ST) is a relatively unusual dental anomaly., It is even more unusual to find patients with distomolar teeth also denominated fourth molar teeth.&#x0D; Presentation of the case: This article describes a clinical case of a 24-year-old patient presenting with a maxillary fourth molar, who was diagnosed by dental x-ray, and surgical resolution of the case.&#x0D; Conclusion: Tooth extraction surgery was the clinical procedure chosen to treat the impacted tooth.

Survey of dental diseases in Crioulo breed horses reared in an extensive farming system

ABSTRACT The present study aimed to identify and quantify dental diseases in Crioulo horses reared exclusively under extensive farming conditions. In total, 254 Crioulo horses were evaluated, that were reared exclusively in native pastures with predominantly Eragrostis plana (Annoni grass). The animals were divided into three groups according to age: three to five years (G1), six to 12 years (G2), and 13 to 26 years (G3). In total, 46.1% of the animals in G1, 63.8% in G2, and 82.3% in G3 had two or more incisor disorders; 37.5% in G1, 52.5% in G2 and 45.5% in G3 had two or more disease findings in the canines; and 28.9% in G1, 35.4% in G2, and 64.7% in G3 had four or more disease findings in the second, third, and fourth premolars and molars. However, dental calculus was observed in 90.5% of G2 animals, whereas in G3, the occurrence rate of excessive enamel points and calculus was 82.4%. Although all of the horses studied were reared in an extensive farming system, dental changes were very common in the Crioulo breed reared under these management conditions.

Fourth molar: A retrospective study and literature review of a rare clinical entity.

PurposeThe prevalence of supernumerary teeth has been reported to be between 0.1% and 3.8%. The aim of this study was to determine the prevalence, clinical significance, and associated pathologies of fourth molars based on a retrospective study and a literature review.Materials and MethodsA 5-year retrospective prevalence study was conducted at the Department of Oral Diagnosis and Dentomaxillofacial Radiology of Okayama University Hospital, Okayama, Japan. The study involved extracting data from the digital records of patients from January 1, 2013 through December 31, 2017. The sampling frame included all patients who had panoramic radiographs, cone-beam computed tomography (CT), and multislice CT images during the period under review.ResultsA total of 26,721 cases were reviewed and 87 fourth molars were identified. The prevalence of fourth molars in the 5-year study at Okayama was calculated as 0.32%. The mean age of patients with a fourth molar was 30.43 years, and the male-to-female ratio was 1:0.98. The vast majority of cases were in the maxilla (92%) and had normal shapes (89.7%); furthermore, 82.8% of cases were unerupted.ConclusionThe prevalence of fourth molars in the study population was found to be 0.32%, and fourth molars occurred with approximately equal frequency in males and females. Fourth molars were more common in the maxilla and were predominantly unerupted and small.