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Madagascar is one of the world's foremost biodiversity hotspots with more than 90% of its species endemic to the island. Malagasy carnivorans are one of only four extant terrestrial mammalian clades endemic to Madagascar. Although there are only eight extant species, these carnivorans exhibit remarkable phenotypic and ecological diversity that is often hypothesized to have diversified through an adaptive radiation. Here, we investigated the evolution of skull diversity in Malagasy carnivorans and tested if they exhibited characteristics of convergence and an adaptive radiation. We found that their skull disparity exceeds that of any other feliform family, as their skulls vary widely and strikingly capture a large amount of the morphological variation found across all feliforms. We also found evidence of shared adaptive zones in cranial shape between euplerid subclades and felids, herpestids and viverrids. Lastly, contrary to predictions of adaptive radiation, we found that Malagasy carnivorans do not exhibit rapid lineage diversification and only marginally faster rates of mandibular shape evolution and to a lesser extent cranial shape evolution, compared to other feliforms. These results reveal that exceptional diversification rates are not necessary to generate the striking phenotypic diversity that evolved in carnivorans after their dispersal to and isolation on Madagascar., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)

Craniomandibular osteopathy (CMO) is a proliferative, self-limiting, non-neoplastic disease of growing dogs characterised by excessive new bone formation on the skull and mandible. The radiographic findings of CMO are well described; however, limited reports of the computed tomographic (CT) appearance are available. This paper aims to characterise the spectrum of CT findings that can occur with CMO. The study is retrospective, descriptive, multicenter, and includes 20 cases. Age at presentation ranged from 6 weeks to 12 months, with no sex predisposition. Scottish terriers were overrepresented (65%); other breeds included Cairn terrier, Jack Russell terrier, Staffordshire bull terrier, labrador retriever, golden retriever, akita and Slovakian rough-haired pointer (one of each breed). Terrier breeds represented 80% (16/20) of the patient cohort. Mandibular osteoproliferation was present in all patients (marked in 80%, bilateral in 95%), affecting the rostral mandible in 25%, body in 85%, and ramus in 80%. Tympanic bulla osteoproliferation was present in 60% (12/20) of patients (all marked, bilateral in 75%). Cranial osteoproliferation (frontal, parietal, temporal, occipital bones or maxilla, or combinations of them) was present in 90% (18/20) of patients (40% marked, 27% moderate, 33% mild). Nasopharyngeal narrowing was seen in all 12 patients with tympanic bulla osteoproliferation (67% marked, 27% moderate) and caused nearly complete occlusion in two of them. External ear canal stenosis was seen in 55% (11/20) of patients (63% marked, 37% moderate, all bilateral). Temporomandibular joint (TMJ) impingement was suspected in 83% (10/12) of patients with marked tympanic bulla osteoproliferation (75% bilateral). Osteolysis with a moth-eaten pattern was seen in the mandible of 10/20 dogs, the calvarium of 5/20 dogs, and the maxilla of 1/20 dogs (5%). Lymphadenomegaly (mandibular and medial retropharyngeal) was found in 15/20 patients (70% mild, 30% moderate). The most severe CT changes were seen in Scottish terriers. CT allows for detailed characterisation of the bony changes associated with CMO, including the effects occurring secondary to osteoproliferation surrounding the tympanic bullae such as TMJ impingement, external ear canal stenosis, and nasopharyngeal narrowing. Osteoproliferation affecting the cranium and the presence of osteolysis were seen more frequently in this study than previously reported in CMO., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Pérez López, Almansa Ruiz, Steenkamp and Holdsworth.)

Background: Estrogen replacement therapy (ERT) is a common hormonal treatment for postmenopausal women, aimed at alleviating menopausal symptoms and reducing the health risks associated with estrogen deficiency. However, the impact of ERT on temporomandibular disorders (TMDs) remains unclear. This systematic review aims to evaluate the relationship between ERT and TMDs, including TMD occurence, pain, and associated symptoms., Methods: A comprehensive search of seven electronic databases was conducted using predefined search terms and Boolean operators. Inclusion criteria encompassed studies examining the association between ERT and TMDs. Two independent reviewers screened the identified articles, extracted data, and assessed the risk of bias using the RoB -2 tool., Results: Search strategy identified a total of 3 articles which met the inclusion criteria. The included studies investigated the impact of ERT on TMD occurrence and its related symptoms. The analysis revealed no significant association between ERT and TMD occurrence. A significant dose relationship was noted in one of the studies while another mentioned the possible relationship of TMD with educational status. Risk of bias among the studies was low, and the overall quality of evidence was deemed to be high., Conclusion: This systematic review suggests that there is no conclusive evidence supporting an increased risk of TMDs among women receiving ERT. The findings indicate that ERT is unlikely to have a noticeable impact on TMDs. However, due to the limited number of studies available, further research is warranted to strengthen these conclusions and explore potential factors that may influence the relationship between ERT and TMDs., (© 2023. The Author(s).)

The relationship between skull morphology and diet is a prime example of adaptive evolution. In mammals, the skull consists of the cranium and the mandible. Although the mandible is expected to evolve more directly in response to dietary changes, dietary regimes may have less influence on the cranium because additional sensory and brain-protection functions may impose constraints on its morphological evolution. Here, we tested this hypothesis by comparing the evolutionary patterns of cranium and mandible shape and size across 100+ species of carnivoran mammals with distinct feeding ecologies. Our results show decoupled modes of evolution in cranial and mandibular shape; cranial shape follows clade-based evolutionary shifts, whereas mandibular shape evolution is linked to broad dietary regimes. These results are consistent with previous hypotheses regarding hierarchical morphological evolution in carnivorans and greater evolutionary lability of the mandible with respect to diet. Furthermore, in hypercarnivores, the evolution of both cranial and mandibular size is associated with relative prey size. This demonstrates that dietary diversity can be loosely structured by craniomandibular size within some guilds. Our results suggest that mammal skull morphological evolution is shaped by mechanisms beyond dietary adaptation alone., (© 2022 The Authors. Evolution © 2022 The Society for the Study of Evolution.)

This case report describes the successful physical therapy management of a 40-year-old female who presented with left ear pain referred from the temporomandibular joint. Diagnosis was primarily based on clinical examination findings and ruling out of red flags. Guidance was given on active self-care approaches consisting of pain neuroscience education designed with individualized pain curriculum, exercise therapy, manual therapy, and breathing exercises for a period of  sixweeks. Clinically meaningful improvements were obtained in the outcome measures of Numeric Pain Rating Scale (NPRS), Patient-Specific Functional Scale (PSFS), and Global Rating of Change (GROC) scale and progress in Pain-Self Efficacy Questionnaire (PSEQ) and Tampa Scale for Kinesiophobia (TSK) scores. Positive changes were achieved with functional activities (chewing, eating, yawing, brushing teeth and physical intimacy), and the patient was pain-free on discharge, which was maintained at a six-month follow-up.

Naked mole-rats (Heterocephalus glaber) are fossorial, eusocial rodents that exhibit the unusual capability of moving their lower incisors independently in lateral and rostroventral directions. The evolution of this trait would presumably also involve concurrent alterations in neck musculature to support and control movements of the lower incisors. In order to assess morphological adaptations that might facilitate these movements, we performed detailed dissections of the neck musculature of adult naked mole-rats. In addition to characterizing attachment sites of superficial, suprahyoid, and infrahyoid musculature, we also quantified muscle mass and mandibular features thought to be associated with gape (condyle height, condyle length, and jaw length). Based on muscle attachment sites, the platysma myoides may contribute to lateral movement of the lower incisor and hemi-mandible in naked mole-rats. The large digastric muscle is likely to be a main contributor to rostroventral movement of each lower incisor. The geniohyoid and mylohyoid muscles also likely contribute to rostroventral movements of the lower incisors, and the mylohyoid may also produce lateral spreading of the hemi-mandibles. The transverse mandibular (intermandibularis) muscle likely serves to reposition the lower incisors back to a midline orientation following a movement., (© 2019 Wiley Periodicals, Inc.)