Investigations on the Growth Pattern of the Maxillary Sinus in Japanese Human Fetuses

Abstract

Summary: The growth pattern of the maxillary sinus was analyzed using 18 human fetuses of both sexes between 9 and 21 weeks of age postconception. The paraffin embedded specimens were cut in series in the frontal and the transversal plane, respectively. The inner surface of the maxillary sinuses was redrawn and surrounded with a digitizer and then the volumes were calculated. A correlation analysis as well as a simple linear regression analysis between the values of the maxillary sinus, different linear values of the nasal cavity and the crown-rump length (CRL) served to prove possible growth relations. The maxillary sinus' Anlage was already identifiable in the 29.8 mm (CRL) fetus. From this first appearance, the maxillary sinus expands not only in posterior direction but also in anterior direction from 11 weeks onwards. The maxillary sinus volume increased from 0.0008 mm3 at the age of 9 weeks to more than 9 mm3 at the age of 21 weeks. The results of the statistical analysis indicated, that the relationship between the maxillary sinus' Anlage and the nasal cavity were strongly influenced by the body size (CRL). This study suggests, that the growth of the maxillary sinus follows special regularities in the early fetal development.

The Pneumatization of the Facial Skeleton in the Japanese Macaque (Macaca fuscata). A Study Based on Computerized Three-Dimensional Reconstructions.

“…Thus, the results of the present study suggest that the size increase of the maxillary sinus within the primate evolution can't be explained satisfactorily only by the increasing skull size. Notwithstanding that development and growth of the maxillary sinus are closely related to the growth of the skull and to the dentition (Wolf et al, 1993), it has been demonstrated that the sinuses also possess a developmental potential of their own (Libersa et al, 1991;Koppe et al, 1994). On the other hand, recent studies by Francis et al (1990) and Oktay (1992), who have revealed that neither cleft lip and palates nor orthodontic malocclusion affect the size of the maxillary sinus, give some doubts about an exclusive structural role of the paranasal sinuses.…”

Understanding the formation of maxillary sinus in Japanese human foetuses using cone beam CT

“…Therefore, MS growth (MSG) is affected by the width of the NC and the lateral border of the maxilla. Kopper et al [8] reported that the MS expands not only in the posterior direction, but also outward in the anterior direction after it first appears and that the MS volume at a gestational age of 9 weeks is very small in Japanese foetuses. MS hypoplasia, which occurs at a frequency of approximately 4.2% [14] to 4.6% [13], is responsible for some abnormalities in the formation of the MS.…”

“…The palatine bone, inferior nasal concha, lacrimal bone and palatine process of the maxilla all play important roles in formation of the MS during development of the lower face. While previous studies have focused on the role of the paranasal sinuses and the morphology of the air sinuses in formation of the NC [8, 15, 18], the involvement of matrix calcification in the surrounding bones in this process remains unknown. Hypoplasia of MS-associated malformation is related to ethmoidal air cells during formation of the NC [14].…”

Evolutionary Changes in the Midface and Mandible: Establishing the Primate Form

“…The maxillary sinus has been identified in the fossil hominoids Dryopithecus and Sivapithecus (Rae, 1999). The space appears very early, being recognizable at 9 weeks in the human (Koppe et al, 1994). The maxillary sinus is rather large in humans, but even more enlarged in the orangutan, where it occupies the entire maxilla and at times extends into adjacent bones (Cave and Haines, 1940;Koppe and Nagai, 1998).…”

“…Supporting this latter view are the observations by Koppe and colleagues (1994Koppe and colleagues ( , 1996aKoppe and colleagues ( , 1996b) that the size of the maxillary sinus is related more closely to skull or body size than to more functionally related measures such as palatal width and length. Regardless, the sinus appears to develop rather independently early in life, but then becomes more coordinated in its growth with the maxilla (Koppe et al, 1994). Many feel that the morphology and function of early paranasal sinuses evolved as an adaptation to respiratory and olfactory needs and modifications to the cranial vault.…”