Speech is a communication method found only in humans that relies on precisely articulated sounds to encode and express thoughts. Anatomical differences in the maxilla, mandible, tooth position, and vocal tract affect tongue placement and broadly influence the patterns of airflow and resonance during speech production. Alterations in these structures can create perceptual distortions in speech known as speech sound disorders (SSDs). As craniofacial development occurs, the vocal tract, jaws, and teeth change in parallel with stages of speech development, from babbling to adult phonation. Alterations from a normal Class 1 dental and skeletal relationship can impact speech. Dentofacial disharmony (DFD) patients have jaw disproportions, with a high prevalence of SSDs, where the severity of malocclusion correlates with the degree of speech distortion. DFD patients often seek orthodontic and orthognathic surgical treatment, but there is limited familiarity among dental providers on the impacts of malocclusion and its correction on speech. We sought to review the interplay between craniofacial and speech development and the impacts of orthodontic and surgical treatment on speech. Shared knowledge can facilitate collaborations between dental specialists and speech pathologists for the proper diagnosis, referral, and treatment of DFD patients with speech pathologies.

There is increasing recognition that environmental factors affect human craniofacial development and our risk for disease. A scoping review of the literature was performed looking at environmental influences on craniofacial development to better understand this relationship and investigate what further study is needed to determine how this relationship may impact obstructive sleep apnea.
A comprehensive literature search was performed using the Ovid Medline database from inception to May 2020 with relevance to craniofacial development in 5 clinically oriented variables: diet, secular change, breastfeeding/nonnutritive sucking habits, nasal obstruction/mouth breathing, and masticatory muscle function. The Oxford Centre for Evidence-Based Medicine Levels of Evidence was used to assess studies based on study design.
We initially identified 18,196 articles, of which 260 studies were fully reviewed and 97 articles excluded. The remaining 163 articles were categorized as follows: secular change (n = 16), diet (n = 33), breastfeeding/nonnutritive sucking habits (n = 28), nasal obstruction/mouth breathing (n = 57), and masticatory muscle function (n = 35). Ninety-three percent of included studies reported a significant association between craniofacial morphology and environmental factors. The majority of studies were characterized as low-level-of-evidence studies, with 90% of studies being a level-of-evidence of 4 or 5.
The studies in this review suggest that environmental factors are associated with changes in craniofacial development. However, most studies were heterogeneous and low-level studies, making strong conclusions about these relationships difficult. Future rigorous studies are needed to further our understanding of environmental influences on craniofacial development and obstructive sleep apnea risk.
Yu JL, Tangutur A, Thuler E, Evans M, Dedhia RC. The role of craniofacial maldevelopment in the modern OSA epidemic: a scoping review. J Clin Sleep Med. 2022;18(4):1187-1202.

OBJECTIVE: To systematically investigate and critically appraise the quality of the currently available literature regarding the morphological, postural, and functional changes observed in individuals following glossectomy.
METHODS: A search without restrictions in eight databases (including grey literature) and hand searching from inception until March 2018 was performed. Data on morphological, postural, and functional changes after glossectomy were reviewed. Methodological quality was evaluated using the risk of bias in nonrandomized studies of intervention tool.
RESULTS: Out of 835 initially identified unique records, only three articles following patients for 1 year after glossectomy fulfilled the selection criteria. Overall, no significant morphological, postural, and functional changes were observed. Only the distance between the dorsum and the nasal line increased and the freeway space decreased significantly.
CONCLUSIONS: Overall, no significant differences were noted in the medium term, in terms of dentofacial structures adaptation and tongue function following glossectomy. Further research is warranted in order to elucidate the consequences of the altered oral environment.

OBJECTIVE: The RASopathies are a group of syndromes that have in common germline mutations in genes that encode components of the Ras/mitogen-activated protein kinase (MAPK) pathway and have been a focus of study to understand the role of this pathway in development and disease. These syndromes include Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NSML or LEOPARD syndrome), neurofibromatosis type 1 (NF1), Costello syndrome (CS), cardio-facio-cutaneous (CFC) syndrome, neurofibromatosis type 1-like syndrome (NFLS or Legius syndrome) and capillary malformation-arteriovenous malformation syndrome (CM-AVM). These disorders affect multiple systems, including the craniofacial complex. Although the craniofacial features have been well described and can aid in clinical diagnosis, the dental phenotypes have not been analysed in detail for each of the RASopathies. In this review, we summarize the clinical features of the RASopathies, highlighting the reported craniofacial and dental findings.
METHODS: Review of the literature.
RESULTS: Each of the RASopathies reviewed, caused by mutations in genes that encode different proteins in the Ras pathway, have unique and overlapping craniofacial and dental characteristics.
CONCLUSIONS: Careful description of craniofacial and dental features of the RASopathies can provide information for dental clinicians treating these individuals and can also give insight into the role of Ras signalling in craniofacial development.

BACKGROUND: Opitz syndrome (OS) is a genetic disorder that affects mainly the development of midline structures, including the craniofacial region, embryonic heart, and urogenital system. The manifestations of X-linked OS are believed to be results of a malfunctioned gene, MID1, whose product has been shown to have ubiquitin E3 ligase activity and regulate the turnover of microtubular protein phosphatase 2Ac. MID2, a homolog of MID1, shares high structural and functional similarities with MID1. Identification of a missense mutation in MID2 in an Indian family causing overlapping phenotypes with OS provided the first evidence that MID2 might be involved in similar pathogenesis.
METHODS: The clinic features and the genetic findings of all reported X-linked OS were collectively summarized in this research. Real-time RT-PCR and in situ hybridization were used in the expression studies of Mid1/Mid2 in mouse embryos.
RESULTS: Up-to-date, 88 different mutations have been identified in MID1 and most mutations occurred on the conserved amino acids of MID1 and MID2. Expression studies using real-time RT-PCR implicated a tendency of a mutually repressive expression pattern between Mid1 and Mid2 in mouse embryos. Further investigations using in situ hybridization revealed strong expressions of Mid1 and Mid2 in the epithelium of approaching facial prominences and downregulated expressions after fusion in mouse embryos.
CONCLUSIONS: Our results support the hypothesis of functional redundancy of Mid1/Mid2 and their potential roles in regulating tissue remodelling in early development.

The development of the head and the face requires an intimate interaction between two mesenchymal populations, a paraxial mesoderm and neural crest cells for the morphogenesis of the musculoskeletal components of the calvaria, the face and the branchial regions. The disruptions in these interactions can cause foetal fatalities or congenital craniofacial anomalies. We are describing a rarest case with a craniofacial malformation, who was born with complete absence of the facial skeleton and the neck structures, a set of well developed ears in their normal locations and eyelids at the junction between the head and the thorax.