Histological characteristics of macrodontic cheek teeth of guinea pigs

Macrodontia is the enlargement of tooth dimensions of different ethologies. This work aims to show a histological evaluation of macrodontic teeth in guinea pigs. The material was obtained from animals postmortem. Ninety structural changes derived from 24 guinea pigs were evaluated. All teeth used in the study showed macrodontic changes. The samples were decalcified, dehydrated and embedded in paraffin. Material was cut in the transverse and longitudinal planes in relation to the alveolar bone. Histological evaluation included apical bud cells, pulp cavity cells, periodontium, dentin, enamel, cementum and alveolar bone tissue. Individual elements were evaluated with respect to their morphology and distribution. Moreover, the arrangement of the individual hard tooth structures was assessed on the teeth. No atypia was found among the cells that make up the apical bud, pulp or periodontal cavity. Displacement of periodontal cells or odontoblasts towards the pulp cavity as well as disorganization of the cell system in the pulp cavity were observed. Changes in the dentine ligaments and the reconstruction of the alveolar bone were also observed in areas where dentine and cement systems were affected. Dental slides were observed and showed that the enamel is also involved in structural remodelling of the pulp cavity. The histological assessment revealed that structural changes in macrodontic teeth involve the rearrangement of typical tooth tissues.

Neonatal stunting and early childhood caries: A mini-review

The nutritional status of pregnant women greatly determines their newborn outcome. Deficiencies of several micronutrients are associated with stunting in early childhood, affecting health into adulthood. However, apart from the systemic disease that has been a concern so far, fetal undernutrition can also be associated with dental caries in a child's early life, especially since the primary teeth begin to form during the mother's gestation period. The important thing to underline regarding the intrauterine formation of primary teeth is especially in terms of enamel formation. One of the causes of developmental enamel defects that will contribute to the emergence of early childhood caries is the malnutrition of the pregnant mother. This mini-review aims to understand the linkage mechanism behind neonatal stunting to early childhood caries. This concept is expected to generate further research to help prevent both growth stunting and early childhood caries. In addition, with some evidence-based research, the importance of the first dental visit can be further promoted.

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.

Tooth agenesis: What do we know and is there a connection to cancer?

Like all developmental processes, odontogenesis is highly complex and dynamically regulated, with hundreds of genes co-expressed in reciprocal networks. Tooth agenesis (missing one or more/all teeth) is a common human craniofacial anomaly and may be caused by genetic variations and/or environmental factors. Variants in PAX9, MSX1, AXIN2, EDA, EDAR, and WNT10A genes are associated with tooth agenesis. Currently, variants in ATF1, DUSP10, CASC8, IRF6, KDF1, GREM2, LTBP3, and components and regulators of WNT signaling WNT10B, LRP6, DKK, and KREMEN1 are at the forefront of interest. Due to the interconnectedness of the signaling pathways of carcinogenesis and odontogenesis, tooth agenesis could be a suitable marker for early detection of cancer predisposition. Variants in genes associated with tooth agenesis could serve as prognostic or therapeutic targets in cancer. This review aims to summarize existing knowledge of development and clinical genetics of teeth. Concurrently, the review proposes possible approaches for future research in this area, with particular attention to roles in monitoring, early diagnosis and therapy of tumors associated with defective tooth development.