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Background: Molar–incisor hypomineralisation (MIH) is a prevalent condition, and how it is managed varies greatly between professional groups. Aim: To explore, and compare, the UK and Australian general dental practitioners' management of MIH in children. Design: Face‐to‐face (remote) semistructured interviews were undertaken, using country‐specific topic guides. Participants were purposively sampled and recruited through national conferences and research networks (eviDent Foundation and Northern Dental Practice Based Research Network). Interviews (from each country) were audio‐recorded, transcribed verbatim and independently analysed using thematic analysis. Results: Two major themes arose from the UK interviews: (i) decision‐making complexities and understanding of treatment options and (ii) need for specialist input. The main Australian themes were (i) multidisciplinary approach to management supporting decision‐making complexities and (ii) economic implications for care. Several difficulties, such as financial implications, multidisciplinary care and clinical decision‐making, were identified as barriers to effectively managing MIH by GDPs in primary care. Conclusion: There are similarities and differences in the knowledge and management of MIH amongst UK and Australian nonspecialists. The different healthcare systems played a significant role in shaping how GDPs manage MIH with barriers relating to affordability, multidisciplinary care and clinical decision‐making. [ABSTRACT FROM AUTHOR]

Diprotodontians are the morphologically and ecologically most diverse order of marsupials. However, an approximately 30-million-year gap in the Australian terrestrial vertebrate fossil record means that the first half of diprotodontian evolution is unknown. Fossil taxa from immediately either side of this gap are therefore critical for reconstructing the early evolution of the order. Here we report the likely oldest-known koala relatives (Phascolarctidae), from the late Oligocene Pwerte Marnte Marnte Local Fauna (central Australia). These include coeval species of Madakoala and Nimiokoala, as well as a new probable koala (?Phascolarctidae). The new taxon, Lumakoala blackae gen. et sp. nov., was comparable in size to the smallest-known phascolarctids, with body-mass estimates of 2.2–2.6 kg. Its bunoselenodont upper molars retain the primitive metatherian condition of a continuous centrocrista, and distinct stylar cusps B and D which lacked occlusion with the hypoconid. This structural arrangement: (1) suggests a morphocline within Phascolarctidae from bunoselenodonty to selenodonty; and (2) better clarifies the evolutionary transitions between molar morphologies within Vombatomorphia. We hypothesize that the molar form of Lumakoala blackae approximates the ancestral condition of the suborder Vombatiformes. Furthermore, it provides a plausible link between diprotodontians and the putative polydolopimorphians Chulpasia jimthorselli and Thylacotinga bartholomaii from the early Eocene Tingamarra Local Fauna (eastern Australia), which we infer as having molar morphologies consistent with stem diprotodontians. [ABSTRACT FROM AUTHOR]

To evaluate correlations between Diagnodent laser fluorescence readings and clinical scores for smooth (buccal and lingual) surfaces of primary canines and molars, with particular interest in white spot lesions. Materials and Methods: A total of 17,088 primary molars and canines in 712 children aged 5 to 7 years residing in the Bayside Health Service District, Queensland, Australia were examined on an annual basis over a 3-year period by one calibrated examiner. Clinical scores and Diagnodent readings were assigned after overlying deposits of plaque had been removed. Results: Data from a total of 33,029 sites were subjected to frequency analysis using SPSS. Combining buccal and lingual surfaces together, the mean Diagnodent values were: sound (ICDAS 0): 3.3; visible white spot lesion (ICDAS 1+2): 7.7; decay with cavitation into dentine (ICDAS code 5): 37.2; and gross decay with an open cavity (ICDAS code 6): 62.0. Diagnodent scores did not, however, follow Gaussian distributions. White spot lesions showed a significant increase in Diagnodent scores, compared with sound enamel. Longitudinal analyses showed a similar proportion of sites which worsened in both caries score and in Diagnodent score. The same was true for sites which showed improvement over time, indicative of reversal, where Diagnodent scores reduced by 10 or more. Conclusions: This large-scale clinical study establishes that there is a progression in laser fluorescence scores with increasing severity of smooth surface enamel lesions in primary teeth, from sound smooth surface enamel through white spot lesions and subsequently to cavitation; however, the Diagnodent should not be relied on as the sole means for caries diagnosis because of the possibility of false positive readings if plaque remains on the surface. The joint findings of increased scores with incipient decalcified lesions affecting enamel, and changes in readings aligning with caries reversal or progression lend some support to the clinical use of Diagnodent as an aid in monitoring the progress of early stages of the caries process on smooth surfaces. [ABSTRACT FROM AUTHOR]

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Quaternary palaeontologists are often asked to identify and interpret faunal remains from archaeological excavations. It is therefore vital that both palaeontologists and archaeologists understand the limitations imposed by recovery methods, especially sieves. Fossil small mammals, particularly rodents, in Australian archaeological deposits are very significant sources of palaeoenvironmental information. Over the last half century, recovery techniques used by archaeologists in Australia have ranged from dry screening with 10 mm sieves to wet screening with nested sieves graded down to 1 mm. Nested 6 and 3 mm sieves have been a popular combination. Experimental investigations, using owl-accumulated mammal remains from two caves, show that sieves of 2 or even 3 mm (the metric equivalent of 1/8th inch) are fine enough to recover most of the dissociated complete jaw bones used to identify Australian native rodents (all Muridae). But they fail to retain first molar teeth that have become dissociated from the jaws by pre-depositional fragmentation, predator digestion or damage during excavation. A 1.63 mm sieve (the approximate metric equivalent of 1/16th inch) differentially recovers all isolated first molars of Australian ratsized rodents, but not small mice, or some first molars of large mouse species. Our results show that differential recovery statistically significantly biases the relative abundances of rodent species retained on a sieve, although there is considerable inter-species variability. The diagonal dimension of the mesh aperture is confirmed to be at least as important as the side dimension in determining what is lost through a sieve. The demographic structure of species can also be biased by differential loss of isolated molars from the youngest individuals, but only in species whose molar dimensions precisely span the threshold of retention on a particular sieve size. Some data suggest that a greater proportion of small objects will be lost through a sieve when immersed in water, than with sprayed water wet sieving or dry screening. Because highly fragmented faunal materials are characteristic of many Australian archaeological deposits, complete recovery of isolated first molars is essential for detection and identification of rodent species to produce the comprehensive assemblages needed for valid comparisons with accumulations by single predators such as owls, and for the multivariate analyses used in palaeoenvironmental interpretations. Complete recovery of first molars of Australian rodents requires a sieve mesh aperture no larger than 1 mm square. A recent archaeological collection made with such methodology provides an opportunity to demonstrate that a more meticulous standard is worth the time and effort to pursue. [ABSTRACT FROM AUTHOR]

Background: Molar-Incisor Hypomineralisation (MIH) is a prevalent developmental defect of tooth enamel associated with a high burden of disease. The present study aimed to survey Australian and Chilean oral health care practitioners (OHCPs) working in public dental facilities and to compare their knowledge, clinical experience and perceptions about MIH. Findings would give insights about how current knowledge has penetrated into OHCPs working into the public systems. Methods: A mixed-mode survey regarding MIH was carried out amongst Australian and Chilean OHCPs from the public sector. The survey required responses to questions regarding sociodemographics, clinical experience, perceptions, clinical management and preferences for further training. The level of knowledge regarding MIH was determined by Delphi methods for consensus. Data analysis utilised Chi-square, linear and logistic regression models using SPSS Ver. 22.0. Results: The majority of respondents had observed MIH in their patients (88.6 %) and the level of knowledge regarding MIH was high in Australian participants (p = 0.03). Australian respondents felt more confident when diagnosing (OR 8.80, 95 % CI 2.49-31.16) and treating MIH-affected children (OR 4.56, 95 % CI 2.16-9.76) compared to Chilean respondents. Oral health therapists reported higher levels of confidence than Australian general dental practitioners when providing treatment to children with MIH (OR 7.53; 95 % CI 1.95-29.07). Conclusions: Continuing to update clinical guidelines may help practitioners increase their understanding when diagnosing and treating MIH-affected children. Dissemination of information and awareness regarding MIH is necessary in public clinics, and in particular Chilean general dental practitioners should be alerted to these factors. [ABSTRACT FROM AUTHOR]

Aim This study aimed to determine the degree of discrepancy between clinical measurement of furcation involvement ( FI) and cone beam computed tomography image analysis of multirooted teeth. Methods FI measurements obtained from clinical records were compared to CBCT images of the same teeth to determine the degree of discrepancy between CBCT FI grading and clinical FI grading. Results Of the hundred and fifty-four sites analysed, 22% of FI measurements from probing and CBCT were in agreement. Fifty-eight percent of clinical FI recordings were overestimated, and 20% were underestimated when compared to CBCT analysis. Conclusion Clinical recording of FI is both over and underestimated compared to CBCT analysis. This was highest for probing recording grade I furcation involvement where it was highly overestimated. The occurrence of over and under estimation of FI will affect the assignment of prognosis to multirooted teeth, which can influence treatment planning for periodontal therapy and may result in inappropriate treatment. [ABSTRACT FROM AUTHOR]

Few dental anthropological studies have investigated the associations between tooth crown size and crown traits in humans using quantitative methods. We tested several hypotheses about overall crown size, individual cusp areas, and expression of Carabelli cusps in human permanent first molars by obtaining data from standardized occlusal photographs of 308 Australians of European descent (171 males and 137 females). Specifically, we aimed to calculate the areas of the four main molar cusps, and also Carabelli cusp, and to compare the relative variability of cusp areas in relation to timing of development. We also aimed to compare cusp areas between males and females and to describe how Carabelli cusp interacted with other molar cusps. Measurements included maximum crown diameters (mesiodistal and buccolingual crown diameters), the areas of the four main cusps, and the area of Carabelli cusp. The pattern of relative variability in absolute areas of molar cusps corresponded with their order of formation, the first-forming paracone displaying the least variation, and the last-forming Carabelli cusp showing the greatest. Overall crown size and areas of individual cusps all showed sexual dimorphism, with values in males exceeding those in females. Sexual dimorphism was smallest for paracone area and greatest for Carabelli cusp area. Overall crown size and cusp areas were larger in individuals displaying a Carabelli cusp, especially the hypocone area. Although the combined area of the protocone and a Carabelli cusp was greater in cuspal forms than noncuspal forms, protocone area alone was significantly smaller in the former. Our findings lead us to propose that, in individuals with the genotype for Carabelli trait expression, larger molar crowns are more likely to display Carabelli cusps, whereas molars with smaller crowns are more likely to display reduced forms of expression of the trait. We suggest that the pattern of folding of the internal enamel epithelium in developing molar crowns, particularly in the protocone region, can be modified by a developing Carabelli cusp. [ABSTRACT FROM AUTHOR]

Intercuspal distances and mesiodistal and buccolingual crown diameters of maxillary pre-molars were recorded from dental casts of 262 Australian Aboriginals. Although mesiodistal and buccolingual dimensions showed sexual dimorphism, no significant differences were noted between the sexes for intercuspal distances. Intercuspal dimensions showed greater variability and fluctuating asymmetry than did either of the traditional measures. No significant differences in heritability were noted among the three dimensions. Correlations between mesiodistal and buccolingual dimensions were higher than those between buccolingual and intercuspal measures. It appears that the sex differences, which are observed in overall crown dimensions, are established after the cusp tips are localized. Intercuspal distances appear to have a strong genetic component of variability, although they show high phenotypic variability and fluctuating asymmetry. Total tooth size may be subject to more intense selective pressures than the sites of initial calcification. [ABSTRACT FROM AUTHOR]

An adult male Eastern Grey kangaroo from a wildlife reserve near Melbourne was submitted for necropsy examination and was discovered to have abnormal dentition. There was no evidence that any premolars or molars had ever been present on the right mandible, whilst the incisors were normal. The age of the kangaroo was estimated to be 1 year 9 months using the right maxillary molars and 2 years 4 months old using the contralateral side, presumably due to the asymmetry of the dental arcades. ‘Lumpy jaw’, a common periodontal disease of kangaroos, from which Bacteroides sp was cultured, was present on the base of the vertical ramus of the left mandible. Complete unilateral absence of premolar and molar teeth in the mandible of a kangaroo has not been described. This condition affected molar progression in both sets of maxillary molars. [ABSTRACT FROM AUTHOR]