New craniodental fossils of Paranthropus robustus from Kromdraai, South Africa (2014-2017 excavations).

Since the initial discovery of Paranthropus robustus at the site of Kromdraai in 1938, the hypodigm of this species has been expanded by subsequent work at the localities of Swartkrans and Drimolen, with a few fossils also known from Cooper's D, Gondolin and Sterkfontein Member 5. Beginning in 2014, systematic excavations at Kromdraai uncovered a large and previously unknown fossiliferous area, shedding light on Units O and P in the earliest part of the site's stratigraphic sequence. The aim of this paper is to provide detailed descriptions and illustrations of 30 P. robustus craniodental specimens recovered between 2014 and 2017 within the Unit P deposits at Kromdraai. This new sample predates all prior conspecific specimens found at this site (including the holotype of P. robustus from Kromdraai, TM 1517). Its basic dental morphology dimensions and cranial features are compared in a preliminary analysis with other P. robustus samples. The P. robustus sample from Kromdraai Unit P documents previously unknown portions of the P. robustus juvenile cranium. The new dental and cranial remains aid in the exploration of potential morphological distinctions between site-specific P. robustus samples and are compared favorably in size and morphology with the small P. robustus specimens from Drimolen (e.g., DNH 7). These findings do not support the hypothesis that the specimens from Drimolen belong to a different taxonomic group. Instead, they reinforce the presence of a significant degree of sexual dimorphism within P. robustus. The Kromdraai Unit P specimens also contribute to the biodemographic profile of P. robustus. The notable prevalence of infants (i.e., juvenile individuals before the emergence of their first permanent molars) mirrors the natural mortality profiles observed in wild chimpanzees. This suggests a closer resemblance in the processes of accumulation in Kromdraai Unit P and Drimolen than at Swartkrans.

Changes in the swallowing pattern and tongue posture during the transition from deciduous to mixed dentition-a longitudinal ultrasonography study.

BACKGROUND: Given the importance that swallowing pattern and tongue posture might have in the aetiology of malocclusion, it appears important to be aware of the physiological changes of tongue function and its posture. OBJECTIVES: The study aimed to assess changes of the swallowing pattern and tongue posture during the transition from the deciduous to mixed dentition and the association between them. MATERIALS AND METHODS: The study included 57 subjects aged 5.87 ±â€…0.5 with normal occlusion, orofacial functions, no history of trauma, or orthodontic treatment. Ultrasonography was used for the assessment of tongue posture and swallowing pattern, where the spontaneous act of swallowing was recorded. To evaluate the possible effect of incisors' eruption, the swallowing pattern and tongue posture ultrasonograms were compared at the deciduous (DD), early mixed (EMD), and intermediate mixed (IMD) timepoints. RESULTS: A significant association between the swallowing pattern and tongue posture at the DD and IMD timepoint was found. Moreover, the visceral swallowing pattern decreases with age (odds ratio [OR] = 0.777), as well as with a prolonged phase IIa (OR = 0.071), while it increases when the tongue is postured on the mouth floor (OR = 5.020). LIMITATIONS: The young age of the investigated subjects, direct contact of the probe, and the determination of the rest phase of the tongue were considered limitations. CONCLUSIONS: No statistically significant changes in swallowing pattern and tongue posture occurred during the transition period; however, a significant association between the swallowing pattern and tongue posture among subjects with normal occlusion, regardless of the dentition phase was detected.

Prevalence of dental floss use in deciduous dentition: A systematic review and meta-analysis.

OBJECTIVES: Adherence to the daily use of dental floss in childhood is recommended by various international health institutions/organizations. This systematic review (PROSPERO number CRD42020205232) aims to evaluate the prevalence of dental floss use in deciduous dentition. MATERIALS AND METHODS: A systematic review was conducted in six databases (B-on, Cochrane Library, PubMed, Scielo, Science Direct and Web of Science) up to December 2020. The CoCoPop mnemonic allowed for obtaining 2333 articles and resulted in the inclusion of 7 observational studies that evaluated the prevalence of dental floss use (primary outcome) in children up to 6 years old. The Joanna Briggs Institute critical appraisal checklist was used to evaluate the risk of bias, showing that most articles presented good quality. Meta-analyses were performed using the proportion of dental floss use (yes or once/day) and the random effects model. RESULTS: The meta-analysis showed a prevalence of dental floss use of only 12.60% (95% CI: 7.69%-18.52%) based on studies with high heterogeneity of results (I2  = 94.75%; 95% CI: 91.44%-96.78%). Six of the seven studies showed that more than 70% of children never used dental floss. CONCLUSIONS: A low prevalence of dental floss use was observed in children up to 6 years old. Given the diversity of evaluating the use of dental floss, different options should be the target of standardization in future studies.

Morphometric characterization of the very young child mandibular growth pattern: What happen before and after the deciduous dentition development?

OBJECTIVES: Numerous tools have been developed to characterize the morphometry of 3D models. The aim of this study was to apply these techniques to better understand the morphometric growth pattern of healthy children's mandibles. MATERIAL AND METHODS: The study sample was composed of 480 very young children aged from 36 gestational weeks to 7 years old. The sample was divided into three subsamples according to the development stages of their deciduous dentition. Several biometric data were collected on 3D mandibular models. RESULTS: There was homothetic growth during the first years of life. Once all deciduous teeth were fully erupted, the mandibular corpus warped more independently of the ramus, and the inter-individual variability was more pronounced. Throughout the growth period, several subgroups could be identified, highlighting the morphological growth pattern of the mandible. CONCLUSIONS: A particular morphogenesis of the mandible during the growth period was observed, which was correlated with deciduous dentition development. In younger individuals, this morphological pattern was mainly characterized by the progressive closure of the chin symphysis and ramus growth. The tongue movements in the oral space, depending on whether the child was bottle- or breast-fed, may explain this result. As the children grew older, the mandible widened to create sufficient space for the developing teeth buds. During the eruption of deciduous dentition, the mandible took on various morphologies, which was likely based on the child's sex and diet. Therefore, we assume that this mandibular morphogenesis is induced by the functional strains affecting the mandible during deciduous teeth development.

Early development of the human dentition revisited.

In this review, classical data on the early steps in human odontogenesis are summarized and updated with specific insights into the development of the upper and lower embryonic jaws to help in understanding some oral pathologies. The initial step of human odontogenesis is classically characterized by two parallel horseshoe-shaped epithelial laminae. These originate from the oral epithelium and an ingrowth into the jaw mesenchyme: the internal dental lamina gives rise to deciduous tooth primordia, while the external vestibular lamina represents the developmental base of the oral vestibule. However, a more complex situation was revealed by recent studies combining analyses of the dental and adjacent oral epithelia on histological sections and computer-aided three-dimensional (3D) reconstructions during the 2nd month of human embryonic development. The dental epithelium forms a mound, where swellings appear later, corresponding to the individual primordia of deciduous teeth. External to the developing deciduous dentition, the 3D reconstructions do not show any continuous vestibular lamina but instead a complex of discontinuous epithelial bulges and ridges. The patterns of these epithelial structures and their relationship to the dental epithelium differ not only between the upper and lower jaws but also between the lip and cheek segments in each jaw. Knowledge of early odontogenesis may help in understanding some oral pathologies. For example, the human lateral incisor has a dual origin: it arises in the area of fusion between the medial nasal and maxillary facial processes and involves material from these two regions. Such a dual origin at the site of fusion of facial processes represents a predisposition to developmental vulnerability for the upper lateral incisor, resulting in its frequent anomalies (absence, hypoplasia, duplication), especially in patients with a cleft lip and/or jaw. Other pathologies, such as a minute supernumerary tooth, desmoplastic ameloblastoma or extraosseous odontogenic cysts are located external to the upper or lower dentition, and might be derived from structures that transiently appear during early development of the oral vestibule in humans.

Development of Jaw and Deciduous Teeth in Japanese Children -Comparing Size of Crown and Alveolar Area between Today and 40 Years Ago.

The purpose of the present study was to investigate change in the size of the jaw and deciduous teeth in Japanese children over the past 40 years by performing measurements on plaster models of the dental arch obtained from children born between 2007 and 2009 (2000s group) and children born between 1968 and 1974 (70s) group. A total of 61 children were enrolled in the 2000s group, comprising 25 boys (average age, 4 years 5 months) and 36 girls (average age, 4 years 4 months), and 93 children in the 70s group, comprising 45 boys (4 years 6 months) and 48 girls (4 years 4 months). The mesiodistal width of the crown, dental arch width, dental arch length, dental arch height, and available arch length in these groups were measured using a 3D measurement system and the sums of the mesiodistal width of the crown and tooth size-arch length discrepancies calculated. The results of the two groups were statistically compared and the following conclusions reached: the size of deciduous teeth has not changed statistically over the last 40 years; the size of the dental arch has decreased in boys (p<0.01), while remaining approximately the same in girls; and the tooth size-arch length discrepancy has decreased, especially in boys (p<0.01). These results indicate that the interdental spaces of the deciduous dentition have decreased, increasing the risk of crowding in Japanese children.

Quantitative proteomic analysis of gingival crevicular fluids from deciduous and permanent teeth.

AIM: Gingivitis commonly progresses to periodontitis in permanent dentition but rarely in deciduous teeth. Little is known about the biochemical differences between gingiva of deciduous and permanent teeth. Here, we compared the protein profiles of gingival crevicular fluids (GCF) from the gingiva of deciduous and permanent teeth. MATERIALS AND METHODS: Forty children with mixed dentition (Hellman's dental age IIIA) were selected and GCF samples were collected from deciduous cuspids and central incisors in the maxilla. Pairs of GCF samples were labelled using isobaric tags to permit quantitative comparison of protein abundance in the samples using liquid chromatography-electron spray ionization-tandem mass spectrometry. RESULTS: Sixty-two proteins were upregulated in deciduous teeth GCF and 54 in permanent teeth GCF. In particular, neutrophil-derived proteins, including myeloperoxidase and lactoferrin, were repeatedly higher in deciduous teeth GCF than in permanent teeth GCF. These differences were verified using ELISA (p < 0.01). In contrast, immunoglobulin components were upregulated in permanent teeth GCF. CONCLUSIONS: Neutrophil-related proteins were enriched in deciduous teeth GCF and immunoglobulins in permanent teeth GCF. This suggests that neutrophil accumulation plays a protective role in innate immunity against bacterial infection in gingival tissue of deciduous teeth.

A Neanderthal deciduous human molar with incipient carious infection from the Middle Palaeolithic De Nadale cave, Italy.

OBJECTIVES: The aim of the study is the assessment of Nadale 1, a Neanderthal deciduous tooth recently discovered in Northeastern Italy in the De Nadale cave (Middle Palaeolithic). Together with the clear archaeological context of the site, this study brings new insight on Neanderthal behavior and dental morphological variability. MATERIALS AND METHODS: We used microCT data to provide a morphological description and morphometric analysis (diameter measurements and dental tissue volumes) of the Nadale 1 human tooth. Microwear analysis, taphonomical investigation and caries identification were performed using a stereomicroscope and Scanning Electron Microscope. RESULTS: In terms of morphology (i.e., incipient tuberculum molare, marked mesial marginal ridge and well-developed mid-trigonid crest connecting the protoconid and the metaconid, deep anterior fovea) and size, Nadale 1 presents features frequently observed in Neanderthal lower first deciduous molars. Microscope investigations reveal the presence of a small pit which could be correlated to an incipient caries. CONCLUSION: Nadale 1 expands the Italian Middle Palaeolithic fossil record and provides further information on Neanderthal dm1s in terms of dimensional and morphological variability. Furthermore, the presence of an incipient caries brings further data on Neanderthal diet.

Association between Low blood lead levels and increased risk of dental caries in children: a cross-sectional study.

BACKGROUND: The objective of this study was to examine the association between low blood lead levels of <5 µg/dL and the development of dental caries among children. METHODS: The Children's Health and Environment Research (CHEER) group recruited a cohort of 7,059 school-aged children from six Korean cities. The final study populations in the permanent and deciduous teeth groups were 1,564 and 1,241 children, respectively, after excluding 4 children with blood lead levels of >5 µg/dL. Compared with the children who did not have dental caries, the risk of having dental caries according to blood lead level was estimated by using the zero-inflated negative binomial model. RESULTS: The geometric mean (geometric standard deviation, maximum) blood lead level was 1.53 µg/dL (1.57, 4.89 µg/dL), and 74.4% of children had a level of <2 µg/dL. Blood lead level was significantly higher in the children with than in those without deciduous dental caries (1.59 vs. 1.51 µg/dL), similarly with permanent dental caries (1.65 vs. 1.51 µg/dL). After adjustment for covariates, deciduous teeth surfaces that were decayed and filled increased significantly with increasing blood lead levels in a dose-dependent manner (prevalence ratio, 1.14; 95% confidence interval: 1.02-1.27). However, the risk of having dental caries in permanent teeth was not linearly associated with the increase in blood lead level. CONCLUSIONS: In the sum of decayed and filled surfaces, we found a significant increase in risk of dental caries of the deciduous teeth with an increase in blood lead levels (<5 µg/dL) but found no statistical significance in the association with decayed and filled surfaces of caries separately.

Caries Preventive Effect of Sodium Fluoride Varnish on Deciduous Dentition: A Clinical Trial.

AIM: The aim of the study is to evaluate the efficacy of intensive application of sodium fluoride varnish in reducing caries incidence among children aged 6 to 7 years. MATERIALS AND METHODS: The study was a randomized controlled trial conducted among 6- to 7-year-old children of Sangamner, Maharashtra, India. Nearly 200 randomly selected children were randomized into two groups: Control group and intervention (varnish) group. Dental examination to record the caries experiences was conducted at baseline and at 1-year follow-up. The fluoride varnish was applied for three times in a week for a period of 1 year. Mean decayed, missed, and filled teeth (DMFT) were compared between and within groups using t-test. RESULTS: Out of 200 participants, there were 3 dropouts for control group and 4 for intervention group. Nearly 55% study participants were males and remaining were females. There was a statistically significant difference between the baseline and follow-up caries levels in varnish group for deciduous dentition. Mean caries reduction in this study was 26%. CONCLUSION: After 1 year of study, we found significant caries reversal in deciduous dentition among the 6- to 7-year-olds after intensive fluoride application. Such a regimen can be advocated to encourage the practitioners and the caregivers alike for early caries prevention. CLINICAL SIGNIFICANCE: Intensive fluoride application (three times a week) once a year was found to be effective in reducing the incidence of detectable carious lesions and can be advocated to the dental professionals to be incorporated in their routine preventive clinical practice.

The JP2 genotype of Aggregatibacter actinomycetemcomitans and marginal periodontitis in the mixed dentition.

AIM: To perform a cross-sectional study on the carrier frequency of JP2 and non-JP2 genotypes of A. actinomycetemcomitans in Moroccan school children and relate the presence of these genotypes to the periodontal status in the mixed dentition. MATERIAL AND METHODS: A plaque sample from 513 children was analysed by PCR. JP2 genotype-positive subjects (n = 46), an equally sized group of non-JP2 genotype-positive subjects, and an A. actinomycetemcomitans-negative group were randomly chosen among the remaining subjects for clinical and radiographic examination. RESULTS: Among 513 children, 46 (9.0%) carried the JP2 genotype and 186 (36.3%) were positive for non-JP2 genotypes, whereas A. actinomycetemcomitans could not be detected in the remaining 281 subjects. Among 75 subjects with mixed dentition and selected for clinical examination, clinical attachment loss (CAL) ≥ 3 mm at two or more periodontal sites on primary teeth was found in the JP2 genotype-positive group only. In total, 6.7% of subjects with primary teeth present showed CAL ≥ 3 mm at two or more sites. CONCLUSIONS: The carrier frequency of the JP2 genotype of A. actinomycetemcomitans was at a comparable level to frequencies previously found in Moroccan adolescent populations. Clinical attachment loss, manifesting already in the primary dentition, was found only in the group of Moroccan children carrying the JP2 genotype of A. actinomycetemcomitans.

Middle paleolithic human deciduous incisor from Grotta del Cavallo, Italy.

OBJECTIVES: In this contribution, we present a morphological description and comparative morphometric analysis of Cavallo D, a human tooth unearthed from the Mousterian FIII sublayer of Grotta del Cavallo (Apulia, Italy). MATERIALS AND METHODS: We used microCT data to provide a detailed morphological description and morphometric analysis of the Cavallo D human tooth based on traditional diameter measurements and 3D enamel thickness. Moreover, new AMS radiocarbon dating of charcoals from layers FII was carried out. RESULTS: Morphological features observed in Cavallo D align the tooth to Neandertals. Similarly, the large size of the tooth (e.g., BL diameter) and the relatively thinner enamel thickness are typical Neandertal traits. 14 C datings of layer FII attribute the tooth to a time range of 45,600-42,900 cal BP (at 68% level of probability). DISCUSSION: Up to now, the Rdi1 Cavallo D represents the most recent Neandertal human remain in southern Italy related to a radiocarbon dated stratigraphy. Moreover, since deciduous teeth have been less investigated than the permanent ones, this contribution brings new data to increase our knowledge on the variability of the Neandertal deciduous dentition.

Is It Possible to induce Artificial Caries-affected Dentin using the Same Protocol to Primary and Permanent Teeth?

AIM: This in vitro study compared the mineral loss of natural and artificially-created caries-affected dentin in primary and permanent teeth using the same protocol to induce caries lesions. MATERIALS AND METHODS: Twenty molars presenting natural occlusal dentin caries lesions (10 primary-PriC and 10 perma-nent-PermC; control group), and 20 sound molars (10 primary -PripH and 10 permanent-PermpH; experimental group), were selected. Occlusal cavities were prepared in teeth of the experimental group that were submitted to pH-cycling for 14 days to simulate caries-affected dentin. All specimens were longitudinally sectioned and prepared in order to obtain Knoop micro-hardness values from 15 to 250 urn depth, starting in bottom of center of natural lesions or cavities. The microhardness (KHN) data were submitted to three-way repeated measures analysis of variance (ANOVA) and Tukey's tests (α = 0.05). RESULTS: Considering all depths, there was no statistically significant differences (p > 0.05) between the mineral loss of the control (PriC = 30.9 ± 6.4 and PermC = 40.8 ± 8.6) and experimental (PripH = 27.3 ± 11.1 and PermpH = 35.5 ± 14.0) groups, neither between primary and permanent teeth. CONCLUSION: The mineral loss of the artificially-created caries-affected dentin is similar to that from naturally developed dentin caries lesions. CLINICAL SIGNIFICANCE: The pH-cycling model may be a suitable method to simulate caries-affected dentin in both permanent and primary teeth.

Pulpotomy Medicaments used in Deciduous Dentition: An Update.

The aim of this paper was to review the history and the scientific literature published on pulpotomy medicaments and to present the findings of these studies. The review showed that pulpotomy of primary teeth has been treated with many different techniques and medicaments, that some of these approaches are controversial and that their results have presented variables of success rates in term of clinical, radiographic and histologic observation. It is important that all clinicians, particularly for pediatric dentists, be up to date with the recent trends in this area of dental treatment for children.

Enamel thickness variation of deciduous first and second upper molars in modern humans and Neanderthals.

Enamel thickness and dental tissue proportions have been recognized as effective taxonomic discriminators between Neanderthal and modern humans teeth. However, most of the research on this topic focused on permanent teeth, and little information is available for the deciduous dentition. Moreover, although worn teeth are more frequently found than unworn teeth, published data for worn teeth are scarce and methods for the assessment of their enamel thickness need to be developed. Here, we addressed this issue by studying the 2D average enamel thickness (AET) and 2D relative enamel thickness (RET) of Neanderthal and modern humans unworn to moderately worn upper first deciduous molars (dm(1)s) and upper second deciduous molars (dm(2)s). In particular, we used 3D µCT data to investigate the mesial section for dm(1)s and both mesial and buccal sections for dm(2)s. Our results confirmed previous findings of an Neanderthal derived condition of thin enamel, and thinner enamel in dm(1)s than dm(2)s in both Neanderthal and modern humans. We demonstrated that the Neanderthal 2D RET indices are significantly lower than those of modern humans at similar wear stages in both dm(1)s and dm(2)s (p < 0.05). The discriminant analysis showed that using 2D RET from dm(1) and dm(2) sections at different wear stages up to 93% of the individuals are correctly classified. Moreover, we showed that the dm(2) buccal sections, although non-conventionally used, might have an advantage on mesial sections since they distinguish as well as mesial sections but tend to be less worn. Therefore, the 2D analysis of enamel thickness is suggested as a means for taxonomic discrimination between modern humans and Neanderthal unworn to moderately worn upper deciduous molars.

[Prevalence of exogenous pigmentations and caries by intake of ferric supplements in primary dentition]. / Prevalencia de pigmentaciones exógenas y caries por ingesta de suplementos férricos en dentición primaria.

Objective: The aim of this study was to determine the prevalence of extrinsic black pigmentation in primary dentition and its relationship with dental caries in children aged 3 to 5 years. Materials and methods: The study design was descriptive, prospective, cross-sectional and observational; The sample of the present study consisted of 79 children who were receiving treatment with ferrous sulfate, who underwent a clinical examination and odontogram. To determine the presence of extrinsic black pigmentation, the Shourie classification was used. Results: A low prevalence of extrinsic pigmentation of 7.6% was found, and children with extrinsic pigmentation had a Ceod of 9.83+-3.601, while those children without the presence of pigmentations had a Ceod of 4.60+-3.248. Conclusions: A significant relationship was found between the Ceod index and extrinsic black pigmentation (p<0.001).

Current Status and Family Factors Influencing Caries in the Deciduous Teeth of Children 3-6 Years of Age in Families Residing in Rural Heishanzui Township.

PURPOSE: To determine the caries status in children's deciduous teeth and examine the influence of family oral health behaviours on the caries status. MATERIALS AND METHODS: This cross-sectional study included 329 children aged 3-6 years in rural Heishanzui Township, Hebei Province, China, and used a completely random sampling method. These children underwent physical and oral health examinations. The questionnaires were given to the parents and caregivers of the examined children. RESULTS: The prevalence of caries in the deciduous dentition among children aged 3-6 years was 80.55%, with a dmft index of 4.93. Children in the caries group ate sweets, chocolates, and carbonated drinks more frequently than did children in the caries-free group (p < 0.05). Children in the caries-free group brushed their teeth more frequently, with parents helping their children brush, more often than did those in the caries-affected group (p < 0.05). The level of parental education and annual household income also had statistically significant effects on the prevalence of caries in the two groups (p < 0.05). Logistic regression analysis revealed that the frequency of eating sweets was a risk factor for caries in deciduous teeth (odds ratio = 2.20; p < 0.05). CONCLUSION: The prevalence of caries in deciduous teeth among children aged 3-6 years in rural Heishanzui Township was high. Compared to children in the caries-affected group, the families and children in the caries-free group had better oral hygiene behaviours. Moreover, the frequency of eating sweets was shown to be a risk factor for caries in deciduous teeth in children aged 3-6 years.

Risk indicators for the severity of erosive wear in deciduous dentition of Mexican schoolchildren aged 5 to 7 years.

The objective of this work was to estimate the prevalence and severity of erosive tooth wear (ETW), and to identify risk indicators of deciduous dentition of a group of schoolchildren from public schools in Tlalnepantla de Baz, State of Mexico. A cross-sectional study was carried out in 352 schoolchildren from 5 to 7 years old. The severity of the ETW was evaluated using the Basic Erosive Wear Examination (BEWE). Risk indicators were evaluated through a survey which included food and beverage consumption, consumption habits, vitamin C consumption, gastroesophageal reflux, heartburn, belching, xerostomia, vomiting and teeth grinding. Multinomial logistic regression models were fitted. The prevalence of ETW was 99.7% (n = 351). Regarding severity, 46.6% were at a null/mild level, 27.3% moderate, and 26.1% severe. Males were more likely to present severe ETW (odds ratio (OR) = 2.23, 95% confidence interval (CI), 1.27-3.93; p = 0.005). The risk indicators for the severity of ETW were the frequent consumption of citrus fruits (OR = 2.09, 95% CI, 1.12-3.89; p = 0.021), fruit juice (OR = 1.99, 95% CI, 1.06-3.75; p = 0.033), processed beverages (OR = 2.15, 95% CI, 1.23-3.78; p = 0.008) and hot sauce (OR = 1.82, 95% CI, 1.03-3.20; p = 0.036). The prevalence of ETW in the deciduous dentition was very high (99.7%) and ~1/3 for severe ETW. The dietary factors associated with severe ETW are part of the regular consumption of Mexican school-age children, which impact their oral health condition. It is important to establish intervention strategies from the infant stage, focused on both children and their caregivers.

Analysis of the Influence of Breastfeeding and Bottle-Feeding upon the Origin of Posterior Crossbites.

(1) Introduction. An analysis was made of posterior crossbites in deciduous dentition and their relation to the type of feeding received by the child, with the objective of determining the influence of the way in which the child is fed in the early stages of life on the development of posterior crossbites. (2) Material and methods. A total of 1401 preschool children between 3 and 6 years of age from Seville (Spain) were included in the study. An intraoral exploration was carried out to assess the presence of crossbites (uni- or bilateral, and functional or not). The study was completed with a parent or legal guardian questionnaire exploring the type of feeding received by the child in the first stages of life, as well as the presence of bad oral habits and their duration. (3) Results. A total of 276 children (19.7%) presented posterior crossbite in occlusion. Uponn centering the midlines, 197 were maintained, indicating that 79 were due to premature contacts (functional crossbites). There were no significant differences in crossbites among the children who had received breastfeeding, though bottle-feeding was seen to favor crossbite. (4) Conclusions. No statistically significant relationship was found between posterior crossbites and breastfeeding, though an association between posterior crossbites and bottle-feeding was observed, with the number of crossbites increasing with the duration of bottle-feeding.

Outcome of Permanent Canine Teeth Following Extraction of Linguoverted Deciduous Mandibular Canine Teeth in 28 Dogs.

Linguoverted mandibular canine teeth (LMC) are a common cause of class 1 malocclusion, which may result in a traumatic occlusion. When deciduous LMC are diagnosed, extraction is commonly performed to alleviate traumatic occlusion. This retrospective study was designed to observe the outcome of the permanent dentition in dogs with a class 1 malocclusion receiving treatment for deciduous LMC. Medical records from a veterinary dental referral hospital were used to identify patients that underwent extraction of deciduous LMC's prior to the eruption of the permanent mandibular canine teeth. The permanent occlusion was then evaluated once the permanent mandibular canine teeth were erupting. Of the 28 dogs identified and treated for deciduous LMC's, 78.6% (22/28) had a normal permanent occlusion. The 6 patients identified with permanent LMC's were all diagnosed when the patients were between 20 and 29 weeks of age. Of these 6 patients, 5 received gingivectomy and gingivoplasty treatment to correct the permanent LMC. Treatment was declined by the pet owner of the sixth patient. Overall, the majority of dogs in this study with a class 1 malocclusion and deciduous LMC's treated with extractions prior to the eruption of the permanent mandibular canine teeth had a normal permanent occlusion.