The early tetrapod Eoherpeton watsoni is known from the mid- to late Carboniferous (late Viséan to Namurian, approximately 346–313 Ma) of Scotland. The holotype is made up of a nearly complete but crushed skull with postcranial fragments. The skull anatomy of Eoherpeton was first described over 40 years ago; however, many details are obscured due to deformation of the specimen, including internal bone surfaces, the palatal bones and dentition, and suture morphology. Most phylogenetic analyses place Eoherpeton as an embolomere/reptilomorph on the lineage leading to amniotes, making it a key taxon for understanding anatomical changes during the fish-tetrapod transition. In this paper, we scanned the holotype using micro-computed tomography and digitally prepared the specimen. Based on these data, we present a revised description of the skull, including sutural morphology, that supplements and amends previous descriptions. New anatomical findings include the presence of a previously unknown tooth-bearing vomer, additional information on the shape of the basipterygoid processes and jaw joint, the ability to visualise the full extent of the pterygoid, and confirmation of the arrangement of the coronoid series. We also note the size of the pterygoid flange, which is larger than previously described for Eoherpeton. The pterygoid flange is widely considered to be characteristic of amniotes and serves as the origin of the medial pterygoideus muscle. The differentiation of the adductor muscles and appearance of medial pterygoideus are thought to have permitted a static pressure bite in amniotes, potentially resulting in greater bite forces and increased dietary range. Thus, the presence and extent of the pterygoid flange in Eoherpeton suggests this feature (and associated changes in feeding mechanism) may have evolved earlier than previously thought. Finally, the skull was digitally repaired and retrodeformed to create a new, hypothetical three-dimensional reconstruction of the skull of Eoherpeton.

Age is one of the most important life history parameters required to understand the dynamics of mammalian populations. Growth Layers Groups (GLGs) are incremental units of calcified tissue in the teeth (dentine and cementum), which represent a pattern of cyclical deposition that can be counted. However, the estimation of absolute age in GLGs demands a skull with teeth, the permission to destroy part of a tooth, equipment to cut the teeth, and experienced GLGs readers. In 1954 Sivertsen proposed an alternative method using cranial suture age (CSA) to establish age categories. However, there are no studies validating the CSA in relation to GLGs. Thus, this study examined whether there is a correlation between age categories proposed by the CSA and chronological age in years from GLGs of South American fur seals (Arctocephalus australis) (N = 52) and of South American sea lions (Otaria flavescens) (N = 37). 93% of the skulls of A. australis and 83.8% of O. flavescens corresponded accurately to the age in years estimated by each cranial suture age range. These results indicated the existence of high correspondence between the CSA and the GLGs age (r: 0.491 for A. australis and r: 0.675 for O. flavescens). However, an adaptation to Sivertsen's method is recommended: using only eight sutures (excluding the premaxillary-maxillary suture for CSA analysis, due to its late fusion), and updating the intervals for cranial sutures, that correspond to 16–32 = adults, 11–15 = young and 8–10 = pups.

Generally, epiglottic cysts have been treated by the puncture technique or surgical resection. However, these techniques can result in accidental injury to the cyst wall. As a result, the contents of the cyst may spread throughout the larynx, trachea and pharyngeal cavity. The ideal treatment would involve complete resection without cyst perforation. We use a completely different approach for the resection of epiglottic cysts, with successful results, which we term the advanced phono-ultra-microsurgical technique. One difference between this method and previous techniques of surgical epiglottic cyst resection is that the cyst is sealed off before resection in order to prevent rupture and spread of its contents. To enable this, we have developed a special device to facilitate suturing of the vocal fold epithelium, utilising a knot-pusher. This suturing technique allows complete removal of epiglottic cysts. Our technique allows optimal prevention of cyst rupture and spread of contents.

Suturing of the nasal septum after septal surgery is a commonly performed procedure designed to prevent complications such as septal haematoma and bleeding. It is also useful for closing any inadvertent tears of the septal mucosa and providing additional support for the cartilage pieces retained in septoplasty. In addition, the suture can be placed through the middle turbinates, stabilising them during the healing process. Placing knots for interrupted sutures in the posterior and middle part of the nasal septum can be technically difficult. We describe a continuous suturing technique for approximating the mucosal flaps following septal surgery.

Premature fusion of cranial sutures underlies the clinical condition of ‘craniosynostosis’, a common human disorder that occurs in both nonsyndromic and syndromic forms. The subgroup of syndromic craniosynostoses usually associates limb abnormalities and facial dysmorphism to skull distortion. Over the past decade, some of the genes causing these phenotypes have been identified. Among these, the gene encoding FGFR2, one of four members of the fibroblast growth factor receptor (FGFR) family, has been shown to account for several severe conditions including Apert, Pfeiffer, Crouzon, Beare–Stevenson and Jackson–Weiss syndromes. Two other FGFRs, FGFR1 and FGFR3, also account for craniosynostoses of variable severity [Pfeiffer, Crouzon with acanthosis nigricans (a pre-malignant skin disorder), and Muenke syndromes]. By contrast, Saethre–Chotzen syndrome and craniosynostosis (Boston-type) arise from mutations in the Twist and muscle segment homeobox 2 (MSX2) transcription factors, respectively. Whereas most FGFR mutations are likely to cause ligand-independent activation of the receptor, leading to an upregulation of signaling pathways, mutations in the basic helix–loop–helix (bHLH) transcription factor Twist appear to induce loss of protein function. This review will summarise and discuss some of the cellular and molecular mechanisms involved in normal and abnormal craniofacial development, focusing on the possible interactions between the different factors controlling membranous ossification.

The dermal skull roof of Acanthostega gunnari Jarvik is described in detail, giving new information on the anatomy, and new reconstructions of the skull in dorsal, lateral and occipital views, as well as sections through the skull at two points. The types of suture are compared with those of temnospondyls and discosauriscids, comparable animals in terms of habit and skull shape. The skull-bones of Acanthostega are much more closely integrated with each other than those of the two later groups. However, regions of relatively less firmly and more firmly sutured regions are comparable in position. This may be connected with having the lateral lines accommodated in tubes in Acanthostega rather than grooves, or some other property of the dermal bone in the later groups that reduced the need for stronger integration. The post-orbital region of the skull (skull table) is the most strongly integrated region, possibly connected with the need for attachment of occipital musculature. The skull table and dentition are the most labile of cranial features among Devonian tetrapods, whereas the snout, cheek, palate and infradentary regions remain conservative. These are for the most part the lateral-line-bearing regions of the skull. The specimens of Acanthostega found at one site on Stensiö Bjerg may form part of a year-group that had perhaps come together for spawning.