Maxillary Alveoli Research Articles

The last Baru (Crocodylia, Mekosuchinae): a new species of ‘cleaver‐headed crocodile’ from central Australia and the turnover of crocodylians during the Late Miocene in Australia

AbstractBaru is a genus that includes several large mekosuchine crocodylians from the Oligo‐Miocene of Australia. Here we describe Baru iylwenpeny sp. nov. from a large sample of cranial bones from the Upper Miocene Alcoota Local Fauna of the Northern Territory. Baru iylwenpeny can be diagnosed by several autapomorphies that include, but are not limited to: extreme reduction of the pneumatic foramina associated with the diverticula that invade the bones of the suspensorium; and enlargement of the postcaniniform maxillary teeth resulting in crowding of the postcaniniform alveoli and a reduction in the number of maxillary alveoli to 12. The new species is the geologically youngest known member of the genus. While species of Baru are a ubiquitous component of Oligo‐Miocene crocodylian assemblages from northern Australia, they are absent from all known Plio‐Pleistocene sites, suggesting the extinction of the genus by the latest Miocene. We suggest that the marked taxonomic turnover of crocodylian assemblages between the Upper Miocene Alcoota Local Fauna and the Lower Pliocene is the result of a short period of severe aridity during the latest Miocene, causing widespread crocodylian extinctions across Australia, followed by the establishment of taxonomically novel crocodylian faunas in the Pliocene. This event mirrors similar contemporary losses of crocodylian diversity in Africa and South America, although these cases are partly driven by local tectonic events. It is likely that late Cenozoic global cooling also played a role in these extinctions.

A new late Eocene alligatoroid crocodyliform from Transylvania

Here we describe a new eusuchian crocodyliform, collected 130 years ago from a shallow marine limestone of the late Eocene (Priabonian) fossil locality of Cluj-Mănăștur, Transylvania, Romania. Diplocynodon kochi n. sp. is represented by a three-dimensionally preserved incomplete skull that may have belonged to a mature individual. The new taxon possesses a relatively narrow and elongated snout and a mediolaterally shallow but anteroposteriorly wide premaxillary-maxillary notch, strengthened by a prominent bony ridge. The nasals are excluded from the naris and the anterior tip of the frontal forms a broad, complex sutural contact with the nasals. Diplocynodon kochi n. sp. possesses, similarly to other members of the genus, 16-17 maxillary alveoli of which the fourth and fifth alveoli are enlarged and confluent; the lacrimal is longer than the prefrontal; the ectopterygoid is situated close to the posteriormost maxillary tooth alveoli, the dorsal margin of the infratemporal fenestra is bordered by the quadratojugal, preventing the quadrate from reaching the fenestra, and the foramen aëreum is situated on the dorsal surface of the quadrate. The occurrence of D. kochi n. sp. in the Priabonian of the eastern part of Central Europe suggests that the genus was still present and probably widespread across the continent that contributed probably to its survival (at least locally) across the Eocene/Oligocene boundary.

Computed tomographic analysis of the dental system of three Jurassic ceratopsians and implications for the evolution of tooth replacement pattern and diet in early-diverging ceratopsians.

The dental system of ceratopsids is among the most specialized structure in Dinosauria by the presence of tooth batteries and high-angled wear surfaces. However, the origin of this unique dental system is poorly understood due to a lack of relevant knowledge in early-diverging ceratopsians. Here, we study the dental system of three earliest-diverging Chinese ceratopsians: Yinlong and Hualianceratops from the early Late Jurassic of Xinjiang and Chaoyangsaurus from the Late Jurassic of Liaoning Province. By micro-computed tomographic analyses, our study has revealed significant new information regarding the dental system, including no more than five replacement teeth in each jaw quadrant; at most one replacement tooth in each alveolus; nearly full resorption of the functional tooth root; and occlusion with low-angled, concave wear facets. Yinlong displays an increase in the number of maxillary alveoli and a decrease in the number of replacement teeth during ontogeny as well as the retention of functional tooth remnants in the largest individual. Chaoyangsaurus and Hualianceratops have slightly more replacement teeth than Yinlong. In general, early-diverging ceratopsians display a relatively slow tooth replacement rate and likely use gastroliths to triturate foodstuffs. The difference in dietary strategy might have influenced the tooth replacement pattern in later-diverging ceratopsians.

A new species of Maomingosuchus from the Eocene of the Na Duong Basin (northern Vietnam) sheds new light on the phylogenetic relationship of tomistomine crocodylians and their dispersal from Europe to Asia

Maomingosuchus acutirostris sp. nov. is a new tomistomine crocodile from the middle–upper Eocene deposits (late Bartonian–Priabonian age, 39–35 Ma) of the Na Duong Basin in northern Vietnam. M. acutirostris can be differentiated from the type species Maomingosuchus petrolicus by having an acute anterior tip of the premaxilla. Both species differ from another Maomingosuchus from Krabi (Thailand) by differences in the surangular–dentary suture and maxillary alveoli. According to our phylogenetic results, M. acutirostris seems to be the sister species to the group M. petrolicus + Krabi-Maomingosuchus. The close relationship between those three tomistomines is supported in the present phylogenetic analysis by three synapomorphies. In our phylogenetic analysis, Maomingosuchus was retrieved in a basal position forming the sister group to Paratomistoma + Gavialosuchus + Melitosaurus + Tomistoma, including the extant Tomistoma schlegelii. This phylogeny indicates three different dispersal events of Tomistominae from Europe towards eastern Asia: 1) for the stem lineage of Maomingosuchus, no later than the late Eocene; 2) for the stem lineage of Penghusuchus pani + Toyotamaphimeia machikanensis, no later than the early–middle Miocene; and (3) for the stem lineage of T. schlegelii, during the Neogene. http://zoobank.org/urn:lsid:zoobank.org:pub:19B27C1E-0A3F-4425-AA8C-F904277DF327

A new crocodylid from the middle Miocene of Kenya and the timing of crocodylian faunal change in the late Cenozoic of Africa

AbstractBrochuchusis a small crocodylid originally based on specimens from the early Miocene of Rusinga Island, Lake Victoria, Kenya. Here, we report occurrences ofBrochuchusfrom several early and middle Miocene sites. Some are from the Lake Victoria region, and others are in the Lake Turkana Basin. Specimens from the middle Miocene Maboko locality form the basis of a new species,Brochuchus parvidens, which has comparatively smaller maxillary alveoli. Because of the smaller alveoli, the teeth appear to be more widely spaced in the new species. We also provide a revised diagnosis forBrochuchusand its type species,B.pigotti. A phylogenetic analysis supports a close relationship betweenBrochuchusand tube-snoutedEuthecodon, but although relationships among crocodylids appear poorly resolved in the set of optimal trees, this is becauseBrochuchusandEuthecodon, along with early Miocene “Crocodylus”gariepensisfrom the early Miocene of Namibia, jointly adopt two distinct positions—either closely related to the living sharp-nosed crocodile (Mecistops) or to a group including the living dwarf crocodiles (Osteolaemus). Character support for a close relationship withMecistopsis problematic, and we suspect a closer relationship toOsteolaemuswill be recovered with improved sampling, but the results here are ambiguous. In either case,Brochuchusis more closely related to living groups not currently found in East Africa. This material helps constrain the timing of crocodylian faunal turnover in the East African Rift Valley System, with endemic lineages largely being replaced byCrocodylusin the middle or late Miocene possibly in response to regional xerification and the replacement of continuous rainforest cover with open grasslands and savannas.UUID:http://zoobank.org/e6f0b219-5f3e-44e5-bdb9-60a4fae8d126

Safety and Efficacy of a New Synthetic Material Based on Monetite, Silica Gel, PS-Wallastonite, and a Hydroxyapatite Calcium Deficient: A Randomized Comparative Clinic Trial.

Background and Objectives: Maxillary bone defects related to post-extraction alveolar ridge resorption are usual. These defects may lead to failure in further surgical implant phases given the lack of bone volume to perform the dental implant. The objective of this clinical assay was to evaluate the safety and efficacy of an experimental synthetic bone substitute in the preservation of post-extraction maxillary alveoli. Materials and Methods: 33 voluntary patients who had at least one maxillary premolar tooth that was a candidate for exodontia (n = 39) and subsequent implant rehabilitation participated. The regenerated alveoli were monitored by means of periodic clinical examinations (days 9 ± 1, 21 ± 4, 42 ± 6, and 84 ± 6), measuring the height and width of the alveolar crest (days 0 and 180 ± 5), measurement of radiodensity using tomographic techniques (days 0–5 and 175 ± 5), and histological examination of biopsies collected at 180 ± 5 days. Results: No significant differences were observed during the entire follow-up period between the two groups with respect to the safety variables studied. A variation in width of −0.9 ± 1.3 mm and −0.6 ± 1.5 mm, and a variation in height of −0.1 ± 0.9 mm and −0.3 ± 0.7 mm was observed for experimental material Sil-Oss® and Bio-Oss®, respectively. The radiodensity of the alveoli regenerated with the experimental material was significantly lower than that corresponding to Bio-Oss®. However, the histological study showed greater osteoid matrix and replacement of the material with newformed bone in the implanted beds with the experimental material. Conclusions: Both materials can be used safely and proved equally effective in maintaining alveolar flange dimensions, they are also histologically biocompatible, bioactive and osteoconductive. The experimental material showed the advantage of being resorbable and replaced with newformed bone, in addition to promoting bone regeneration.

Reappraisal of the morphology and phylogenetic relationships of the alligatoroid crocodylian Diplocynodon hantoniensis from the late Eocene of the United Kingdom

AbstractDiplocynodon is a genus of basal alligatoroid comprising nine species, which spanned the late Palaeocene to middle Miocene of Europe. Despite recent revisions of most Diplocynodon species, one of the earliest named and most complete, Diplocynodon hantoniensis, has not been re-described for over 150 years. This species is known from the remains of numerous individuals from the Priabonian (late Eocene) Headon Hill Formation, which crops out at Hordle (Hordwell) Cliff in Hampshire, United Kingdom. Here we re-describe and diagnose Diplocynodon hantoniensis, providing the first detailed description of postcranial anatomy in Diplocynodon, and indeed any basal alligatoroid. Diplocynodon hantoniensis is diagnosed by four autapomorphies, including retention of the ectopterygoid–pterygoid flexure through ontogeny and a unique anterior process of the ectopterygoid adjacent to the posteriormost maxillary alveoli. A critical review of previously referred remains from elsewhere in Europe and the USA restricts Diplocynodon hantoniensis to the late Eocene of the UK. Through comparisons with extant crocodylians, the well-preserved postcranial skeleton enables the interpretation of numerous muscle attachments in the forelimbs and hindlimbs, providing a potentially rich source of character data for future phylogenetic analyses. Based on a comparison of humeral morphology between a large sample of crocodylian species, we outline two new morphological characters in the humerus. We include D. hantoniensis in a phylogenetic analysis, including all putative Diplocynodon species (103 taxa scored for 187 characters). We use four different character-weighting schemes: equal weighting, implied weighting (k value = 8) and extended implied weighting with k-values of 4 and 8. In general, these weighted analyses produce congruent results with the equal-weights analysis, and increase the resolution within Diplocynodon. We recover a monophyletic Diplocynodon in three of the four analyses. However, the fourth analysis, with the strongest downweighting of homoplastic characters and missing data (extended implied weighting with k = 4), recovers the Palaeocene Diplocynodon remensis outside Diplocynodon. Our comprehensive revision of one of the most completely known Diplocynodon species facilitates comparisons in the genus, as well as between other basal alligatoroids, and forms the basis for comparing postcranial anatomy in other fossil crocodylians.

The Rediscovery and Taxonomical Reexamination of the Longirostrine Crocodylian from the Pleistocene of Taiwan

Abstract. A partial crocodylian skull was found among the paleontological collection at the Archaeological Museum, Waseda University in Honjo-shi, Saitama Prefecture. Following a bibliographical survey, this was verified as a specimen reported by Tokunaga as the first known crocodile from Taiwan but then regarded as lost due to World War II. Molten glass debris is attached to the specimen, suggesting that it had been subject to air raids during World War II in May 1945, most likely at the Waseda University campus. Based on its largest seventh maxillary alveoli and the prominent lateral expansion towards the posterior direction, this specimen was identified as Toyotamaphimeia sp.; up to now a single species under this genus has been reported. The discovery demonstrates that this crocodylian genus once had a wide geographical distribution during the Pleistocene.

Radiographic comparison of the repaired bone in maxillary alveolar cleft of dog by tissue engineering and autogenous bone grafting techniques

BACKGROUND: Dental disease, trauma and maxillofacial surgeries can cause alveolar bone defects. Among different kinds of treatment, autogenous bone grafts is accepted as a golden standard. On the other hand, because of limitation of treatment with autogenous bone grafts, osteogenic cells derived from stem cells are suggested. OBJECTIVES: The aim of this study was to compare the mean density of the repaired bone in maxillary alveolar cleft of dog by tissue engineering and autogenous bone grafting techniques using digital radiography. METHODS: two, 15*15mm, defects were made in the maxillary alveoli of 4 dogs. A stent was placed in the defect to prevent the effects of soft tissue. After 60 days, the defects were filled with tibial auto graft in one side and mesenchymal stem cells were isolated from the neck adipose tissue in the other side. The density of the regenerated bone was evaluated 15, 30, 45, 60, 75 and 90 days after graft implantation by direct digital radiography, Digora windows software (70 KVP, 10 mA and 0.40 seconds). RESULTS: The findings of one-way ANOVA test showed no significant difference between tissue engineering and autogenous bone grafting methods (P-value = 0.94). Visually, the repaired bone pattern was homogenized in autogenous bone graft method but it was cotton-wool in tissue engineering bone graft method. CONCLUSIONS: digital radiography soft ware provides the possibility of quantification of bone repair by densitometry. When autogenous bone graft is not available, tissue engineering bone graft can be considered an acceptable alternative to repair the bone defects.

A Comparative Evaluation of Efficacy and Efficiency of Grayson's Presurgical Nasoalveolar Molding Technique in Patients with Complete Unilateral Cleft Lip and Palate with Those Treated with Figueroa's Modified Technique.

Background:Presurgical nasoalveolar molding (PNAM) has been used for aligning and not only for approximating the maxillary alveolar segments preoperatively but also for improving the nasal symmetry and therefore facilitates primary surgical repairs in cleft patients.Aim:This study was conducted to compare the efficacy and efficiency of Grayson's technique with Figueroa's modified presurgical nasoalveolar technique in complete unilateral cleft lip and palate (UCLP) infants.Materials and Methods:Twenty-two infants aged 10–15 days were randomly divided into two equal groups: Group I treated with Grayson's PNAM technique and Group II with Figueroa's PNAM technique.Results:When we compared nasal asymmetry values preoperatively and postoperatively of Group I and Group II, it was found that the nostril height increased significantly on the cleft side and nostril width decreased significantly postoperatively on the cleft side. When we compared nasal asymmetry values postoperatively of Group I with Group II, all the values were nonsignificant. When we compared the digital maxillary cast analysis outcomes preoperatively and postoperatively in Group I and Group II, it was found that there was a significant reduction in the alveolar gap and there is a significant increase in the arch width. When we compared the efficiency of Group I with Group II, it was found that Group II was more efficient than Group II.Conclusion:This study showed a morphological improvement in nasal symmetry and maxillary alveoli of infants with UCLP treated with both Grayson's PNAM technique and Figueroa's PNAM technique with Grayson's PNAM technique being more efficient.

Evaluation of BMMSCs-EPCs sheets for repairing alveolar bone defects in ovariectomized rats

The aim of this paper is to investigate the effect that bone marrow mesenchymal stem cells (BMMSCs) - endothelial progenitor cells (EPCs), BMMSCs and EPCs sheets have on repairing maxillary alveolar defects in ovariectomized (OVX) rats. In this study, after identification using multi-lineage differentiation and flow cytometry, BMMSCs and EPCs were isolated from female rats. The BMMSCs-EPCs, BMMSCs and EPCs sheets were detected by hematoxylin-eosin (H&E) staining, alkaline phosphatase (ALP) staining and qRT-PCR. Defects were created in maxillary alveoli and repaired with BMMSCs-EPCs, BMMSCs and EPCs sheets in OVX rats. The repair effects were determined by histological staining and micro-CT analysis at 2, 4 and 8 weeks after implantation. We aim to clarify whether BMMSCs-EPCs sheets are more effective in repairing alveolar bone defects than are BMMSCs and EPCs sheets in OVX rats. The results show that the osteogenic potential and the effect of bone repair are greater in the BMMSCs-EPCs sheet group and that this group has a higher ability to repair alveolar bone defects in OVX rats. These results suggest that BMMSCs-EPCs sheets have potential in clinical applications for treating humans with osteoporosis.

Root Tip Recovery via Root Canal Instrumentation

This article reviews 2 representative cases of root tip recovery by root canal instrumentation. Recommendations associated with the use of root canal instrumentation for root tip recovery within mandibular and maxillary alveoli are considered.

Diagnostic value of cone-beam computed tomography and periapical radiography in detection of vertical root fracture.

Vertical root fracture (VRF) is the longitudinal fracture of the root in endodontically treated teeth. Considering the limitations of two-dimensional radiographic images in detection of VRF and introduction of cone-beam computed tomography (CBCT), this study was designed to find the sensitivity, specificity and accuracy of CBCT and periapical (PA) radiography in detection of VRFs. This was a cross-sectional in vitro study on 80 extracted human single canal teeth including 40 maxillary and 40 mandibular teeth. After standardized endodontic treatment of the roots, VRF was induced in half of the teeth in each group, and other half were left without fracture. Teeth were inserted in dry maxillary and mandibular alveoli. PA radiographs and CBCT images were taken from the specimens. Data were analyzed with SPSS software. The McNemar test was used to evaluate the sensitivity, specificity and accuracy of images, and kappa coefficient was used to assess the degree of agreement between the observers. The level of significance was set at 0.05. Sensitivity and specificity values of CBCT were 97.5% and 95%, respectively. However, for PA radiography the sensitivity and specificity were 67.5% and 92.5%, in order of appearance. Accuracy of CBCT (96.25%) and PA radiography (80%) in both jaws were significantly different (P=0.022). Two methods were not significantly different when testing specificity (P=0.298). This study showed that the sensitivity and accuracy of CBCT in detection of vertical root fracture are higher than periapical radiography. CBCT can be recommended to be used in detection of vertical root fractures.

The cranial osteology of Tyrannoneustes lythrodectikos (Crocodylomorpha: Metriorhynchidae) from the Middle Jurassic of Europe.

Tyrannoneustes lythrodectikos is one of numerous metriorhynchid crocodylomorph species known from the Oxford Clay Formation of England (Callovian-Oxfordian; Middle-Late Jurassic). This taxon is of evolutionary importance, as it is the oldest and most basal known macrophagous metriorhynchid. It has a mosaic of plesiomorphic and derived feeding related characteristics, including: teeth with microscopic, poorly formed and non-contiguous denticles; increased tooth apicobasal length; ventrally displaced dentary tooth row (increased gape); reduced dentary tooth count; and a proportionally long mandibular symphysis. However the type specimen, and current referred specimens, all lack a preserved cranium. As such, the craniofacial morphology of this taxon, and its potential feeding ecology, remains poorly understood. Here we describe two skulls and two lower jaws which we refer to T. lythrodectikos. Previously these specimens were referred to ‘Metriorhynchus’ brachyrhynchus. They share with the T. lythrodectikos holotype: the in-line reception pits on the dentary, dorsal margin of the surangular is strongly concave in lateral view, and the most of the angular ventral margin is strongly convex. Based on our description of these specimens, the skull of T. lythrodectikos has three autapomorphies: very long posterior processes of the premaxilla terminating in line with the 4th or 5th maxillary alveoli, deep lateral notches on the lateral surface of the maxillary with reception pits for dentary teeth, and the premaxilla forms the anterior margin of the first maxillary alveoli. Our description of the cranial anatomy of Tyrannoneustes lythrodectikos confirms that some macrophagous characteristics evolved during the Middle Jurassic, and were not exclusive to the clade Geosaurini. Moreover, the skulls further highlight the mosaic nature of Tyrannoneustes lythrodectikos and wide-gape macrophagous evolution in Geosaurinae.

CAD presurgical nasoalveolar molding effects on the maxillary morphology in infants with UCLP

This study evaluated the effectiveness of computer-aided design-nasoalveolar molding (CAD-NAM) on maxillary alveolar morphology in infants with unilateral cleft lip and palate (UCLP). 15 infants with UCLP treated by CAD-NAM therapy composed the treatment group, and the control group consisted of 15 infants with non-presurgically treated UCLP. The maxillary morphology was analyzed by Rapidform XOR3 software. Differences in all variables pre- and post-CAD-NAM were discussed. Significant difference was found in arch length, cleft gap, labial frenum deviation, A-X, A'-X, and alveolus height on both sides pre- and post-CAD-NAM. This study suggests a trend toward morphological improvement in maxillary alveoli of infants with UCLP treated with CAD-NAM. The CAD-NAM effectively reduced the cleft gap, corrected the maxilla midline, and improved the sagittal length of the maxilla. The alveolar height decreased significantly after the treatment, which indicated that the traction force of the appliance may have obstructive effects on the vertical growth of the alveolar bone.

The cranial anatomy and taxonomy of Peloneustes philarchus (Sauropterygia, Pliosauridae) from the Peterborough Member (Callovian, Middle Jurassic) of the United Kingdom

Abstract: Peloneustes philarchus is the most abundant pliosaurid from the Peterborough Member of the Oxford Clay Formation (Callovian) of the UK. It is a valid taxon possessing a unique character combination, including a single autapomorphy: the interdentary symphysis is raised dorsally on a narrow platform. Twenty‐one specimens can be positively referred to P. philarchus. However, other specimens previously referred to Peloneustes, from the Peterborough Member near Peterborough, and the lower Oxfordian strata of Marquise, northern France, represent distinct, unnamed taxa. The skull of P. philarchus is described in detail, including new information from an uncrushed, three‐dimensionally preserved specimen and a specimen with a well‐preserved palate. Well‐preserved material clearly indicates that P. philarchus lacked nasals, but possessed a lacrimal. A previously unrecognised ‘palpebral’ forms part of the dorsal orbit margin adjacent to the prefrontal. The number of maxillary (30–31) and dentary (36–44) alveoli, the number of dentary alveoli adjacent to the mandibular symphysis (13–15), the number of foramina on the frontal and jugal, the breadth of the parasphenoid, breadth of the anterior (narial) process of the palatine and the presence of a lappet of the angular that extends onto the posterodorsal surface of the retroarticular process vary among individuals but are not considered sufficient to justify the recognition of new taxa. The presence of an open palpebral–prefrontal suture, the size of the ventral midline tubercle of the basioccipital and the presence of an anterior interpterygoid vacuity seem to vary with body size.

Effect of an Aldose Reductase Inhibitor on Alveolar Bone Loss Associated with Periodontitis in Diabetic Rats

Periodontitis is a lesser known but frequent complication of diabetes mellitus and is the major cause of tooth loss in patients with diabetes. Dental therapy for this complication is primarily focused on the control of oral infections. No current therapy directly addresses the potential effects of diabetes itself on this complication. In studies conducted in young normal control and streptozotocin diabetic rats (100 g) treated with and without the aldose reductase inhibitor (ARI) imirestat, experimental periodontitis was induced in one side of the mouth by 3 injections of lipopolysaccharide (LPS) from Escherichia coli 055:B5 9 into the palatal gingiva between the first and second maxillary molars at 48-hour intervals. The other control side was injected with phosphate buffered saline (PBS). Fourteen days after the final injection, all rats were euthanized and the heads were defleshed. The maxillary area was separated from the remaining skull. The cleaned maxillary alveoli were stained in 5% aqueous toluidine blue to identify the cemento-enamel junction (CEJ) on the molars. Alveolar bone loss was measured according to standard methods by determining both the distance between the CEJ and the alveolar bone on the 2 molars between which the injections were made, and by measuring the ratio of root area/enamel area in the same region. These measurements showed that LPS injections resulted in significant bone loss compared with PBS injections in both control and diabetic rats, and that this bone loss was not present in the ARI-treated diabetic rats (P < 0.05). These results suggest that the sorbitol pathway plays a critical role in the pathophysiological mechanism(s) of diabetic periodontitis and that AR may be a direct pharmacological target for the treatment for this disease.

Kambara taraina sp. nov. (Crocodylia, Crocodyloidea), a new Eocene mekosuchine from Queensland, Australia, and a revision of the genus

ABSTRACT Crocodilian cranial material from the Eocene Rundle Formation of eastern-central Queensland is herein attributed to Kambara taraina sp. nov. This is the fourth species of Kambara, the earliest genus of the diverse Australasian subfamily, Mekosuchinae. Although members of this subfamily diversified and radiated throughout the middle and late Tertiary, the clade as a whole is still poorly understood and their early evolutionary history is somewhat enigmatic. The Rundle Formation has yielded an unprecedented amount of crocodilian material for this epoch, with exquisite preservation. The new species is unique in possessing an increased attachment area for the mandibular adductors on the retroarticular process, rostrally extended palatal fenestrae, a rostrocaudally aligned ridge within the pterygoid fossa, and a reduction in maxillary alveoli (14). This combination of characters may reflect a functional divergence of K. taraina from other species, indicating disparate feeding strategies. The inclusion of this fourth species makes Kambara an increasingly diverse genus and as such the generic and specific diagnoses are herein modified accordingly.

Hyalinizing clear cell carcinoma in minor salivary glands of maxillary tuberosity

Hyalinizing clear cell carcinoma (HCCC) is a newly described entity with distinctive histological features. A 48-year-old woman with HCCC was described in minor salivary glands of right maxillary tuberosity with two years duration. Physical examination revealed a red-colored, firm mass measuring 2.0 cm × 1.8 cm with telangiectases in the overlying mucosal surface. Computed tomography scans demonstrated a bony destruction of buccal cortex of maxillary alveoli and right maxillary tuberosity. Resection biopsy, wide excision of the underlying alveoli including part of maxilla was performed. Pathological examination revealed typical clear cells arranged in anastomosing trabeculae, cords, nests, or solid sheets with a hyalinizing stroma. These clear cells were strongly positive for the periodic acid-Schiff (PAS) but were negative for the mucicarmine staining. Immunohistochemically, those neoplastic cells were immunoreactive to cytokeratin, but negative to smooth muscle actin and S-100 protein. Neither recurrence nor distant metastasis was found during the 12-month follow-up period.

Neolithic Tooth Replacement in Two Disturbed Burials from Southern Egypt

During the excavation of a Late Neolithic cemetery near Nabta Playa, Egypt, two crania were recovered that evidenced tooth replacement in antiquity. Both were apparently collected and redeposited by Neolithic people after being disturbed by later burials. In the first case, a young female's maxillary anterior alveoli contained a combination of mandibular and misplaced maxillary teeth. In the second case, another young female's maxilla and mandible contained two incorrectly placed teeth. This, and other evidence, suggest that attempts were made to return these individuals to the soil in as complete of a state as possible—being limited only by the ancient grave-digger's level of anatomical knowledge. A review of the mortuary literature and inquiries made to several leading bioarchaeologists suggest that the tooth replacement seen here may be unique; we have been unable to document comparable treatment in any other context worldwide.