Evidence of late root formation of molars in Anderson's red-backed vole, Eothenomysandersoni (Thomas, 1905) (Cricetidae, Rodentia), and arguments for its generic allocation

We evaluated the molars in Anderson's red-backed vole (n = 114) from the Kii Peninsula of Honshu, Japan. Two of the specimens are considered extremely old aged based on their dimensions and on the loss of alveolar capsules of M², and a third one is also old based on its strongly worn left M³ and M₁. Of the former two individuals, one showed an incipient closure of re-entrant angles at its basal end, as estimated from the difference between the occlusal patterns of the occlusal and basal surfaces of the left M₂. The latter individual also showed a complete closure of the basal end in the left M³. These patterns differ from incipient roots observed in other vole taxa but were similar to a previous example of incipient roots in Anderson's red-backed vole. Therefore, we suggest that molar roots in this species form at an extremely late age or by strong wear. Root formation in molars is considered an important diagnostic character, as Eothenomys molars lack roots, while Craseomys molars develop roots at a late age. However, this dental character may be particularly difficult to assess in voles under natural conditions. Considering previous phylogenetic findings based on molecular analyses, Craseomys is the most appropriate genus for Anderson's and other Asiatic red-backed voles.

Determination of craniofacial and dental characteristics of individuals with Williams-Beuren syndrome by using 3D facial scans and radiographs

BACKGROUND

Williams-Beuren syndrome (WBS) is caused by a microdeletion on chromosome 7q11-23 and clusters a variety of systemic affectations.

AIM

To investigate whether 3D facial scans can detect WBS by objectively addressing their craniofacial, skeletal and dental characteristics, compared with those of a non-affected control group.

MATERIALS AND METHODS

3D facial surface scans of 17 WBS individuals and 33 normal developing patients were analysed. Additionally, cephalometric and panoramic radiographs of subjects with WBS were compared with those of non-affected individuals.

RESULTS

The 3D surface scans showed significant facial differences around the nose and mouth area. The cephalometric aspects of individuals with WBS differed mainly at the lower incisor region. Additionally, hypoplastic tooth morphology seems to be more often present in WBS.

CONCLUSION

3D images are a non-invasive, efficient method to observe facial anomalies and facilitate an early diagnosis of WBS. Additionally, the analysis of the cephalometric and panoramic images revealed significant differences in dental characteristics. Together with early diagnosis through 3D images, these can help in the establishment of adequate medical, dental and orthodontic treatment planning.

Dental and Craniofacial Characteristics in Patients With 14Q22.1-Q22.2 Deletion: A Case Series

This case series is a follow-up report focusing on dental and facial characteristics in patients with a rare microdeletion in chromosome 14q22.1-q22.2. Usually, these patients have severe ocular, brain, and digital abnormalities. However, this case series shows that clinical presentation can be mild. Four relatives spanning 3 generations were diagnosed with a familial autosomal dominant 2.79 Mb microdeletion in chromosome 14q22.1-q22.2. Genetic screening was done by the Bacterial Artificial Chromosome array-comparative genome hybridization and was confirmed by the fluorescence in situ hybridization technique. Dental and craniofacial data were collected from medical files, clinical examinations, clinical photos, panoramic and cephalometric radiographs, and dental casts. Written informed consent for scientific use was obtained for all family members. No larger syndrome could be identified. All cases had similar facial red flag characteristics, consisting of a long face with retrognathia and open mouth relation, associated oral clefts in varying degrees, depressed nasal bridge, delayed tooth development, hypertelorism, and low-set angular ears. The dental casts showed a distal molar occlusion and a lack of space in the dental arches. Developmental delay was noted together with limb defects such as poly- and syndactyly. Microphthalmia and hearing loss were present in the most severe cases. This rare congenital disorder, associated with facial dysmorphia, oral clefts, and tooth agenesis, can remain undiagnosed until adulthood. A family history of short stature, developmental delay, poly- or syndactyly, and micropthalmia are suggestive features. Similar reports help to raise awareness among dental practitioners, leading to an early genetic diagnosis.

Dental Characteristics of Different Types of Cleft and Non-cleft Individuals

Objective

The objective of this study was to compare the novel artificial intelligence (A.I.)-driven lateral cephalometric (Late. Ceph.) analysis of 14 different dental characteristics (DC) among different types of cleft lip and palate (CLP) and non-cleft (NC) individuals.

Materials and Methods

A retrospective study was conducted on 123 individuals [31 = NC, 29 = BCLP (bilateral cleft lip and palate), 41 = UCLP (unilateral cleft lip and palate), 9 = UCLA (unilateral cleft lip and alveolus), and 13 = UCL (unilateral cleft lip)] with an average age of 14.77 years. Demographic details were gathered from the clinical records. A novel artificial intelligence-driven Webceph software has been used for the Late. Ceph. analysis. A total of 14 different types of angular and linear DC measurements were analyzed and compared among groups. Two-way ANOVA and multiple-comparison statistics tests were applied to see the differences between gender and among different types of CLP versus NC subjects.

Results

Of the 14 DC tested, no significant gender disparities were found (p > 0.05). In relation to different types of CLP versus NC subjects, 8 over 14 DC were statistically significant (p < 001 to p = 0.03). Six other DC variables show insignificant (p > 0.05) noteworthy alterations in relation to type of CLP.

Conclusion

Based on the results, type of CLP revealed significantly altered DC compared to NC. Among different types of CLP, BCLP exhibited a maximum alteration in different DC.