Comparison of the dentofacial patterns for native Greek and American-Caucasian adolescents.

The study of the craniofacial relations and variations in man has long been used to differentiate various racial groups in physical anthropology. Morphologic features of different races and ethnic groups are not randomly distributed but appear in geographic clusters. Richardson wonders whether there is only one race, comprising ethnic groups separated by cultural, climatic, and geographic boundaries, causing subtle changes in facial morphology. Since the introduction of roentgenographic cephalometry in orthodontics, several methods of analysis have been developed for clinical diagnosis and treatment planning. Also, these methods have been used to establish the cephalometric norms of different ethnic groups: American Negro, Australian aborigine, American Mexican, Norwegian, Indian, Japanese, Swedish, and Iranian. Sassouni, Ricketts, and others have concluded that norms differ between Caucasians and other ethnic and racial groups. Ethnic differences in facial traits do exist. Awareness of the normal dentofacial pattern of each ethnic group will undoubtedly ensure better success of treatment to establish optimal facial harmony. These conclusions prompted the present investigation, which compares Greek and American-Caucasian dentofacial patterns of adolescents, and provides information on the facial characteristics of Greek adolescents. To date, no similar study has been made.

A comparative cephalometric investigation of the Greek craniofacial pattern through 4,000 years.

A comparative cephalometric investigation was conducted between modern and ancient Greeks to determine craniofacial characteristics and to examine the significance of ethnic heritage. The modern sample was composed of 54 individuals chosen on the basis of ethnic background, normal occlusion and facial harmony. The ancient sample consisted of 40 skulls with normal occlusion dated back to the Minoan civilization (ca. 1,800-1,200 B.C.). A remarkable similarity in craniofacial morphology was revealed between the two groups, suggesting a close genetic affinity between modern and ancient Greeks. The ability of the craniofacial complex to make compensatory or balancing changes was noted. The craniofacial complex was seen to function as an integrated biological entity. Moreover, the cranial base showed a definite influence on skeletal profile configuration. These results provide a more comprehensive understanding of how craniofacial variables interact and contribute to the morphology of the dentofacial skeleton.

A simple procedure to assess esthetic preference for dentofacial treatment.

A procedure is described in which lateral facial photographs were cut apart and reassembled in ways that approximated desired esthetic change. Two groups of subjects were asked to complete the Sassouni "cut-up-paste-back" procedure. Group 1 consisted of 20 adult dental professionals; group 2 comprised 18 college students unacquainted with dental studies. Both groups made similar alterations on a photograph at the beginning and at the end of a 2-week period. Photographic alterations were highly similar to written descriptions of intended changes. The "cut-up-paste-back" procedure is a simple and inexpensive way to facilitate dentist-patient communication during treatment planning. The procedure also has applicability for research in facial esthetic preference.

The influence of perennial allergic rhinitis on facial type and a pilot study of the effect of allergy management on facial growth patterns.

Perennial rhinitis with an allergic component (PRAC) in association with chronic mouthbreathing has been thought to cause skeletal open-bite facial type and narrow transverse facial dimensions. The object of this study was to supply data for this theory and to determine if allergy management would alter the course of facial growth. When a group of children, aged 5 to 10 years, with PRAC was compared with a matched control sample, a significantly larger palatomandibular angle and lower anterior facial height were found for the PRAC group. Transverse cephalometric measurements showed significantly narrower bilateral orbital breadth, bizygomatic, and binasal dimensions (narrower face) of the PRAC patients compared with the control sample. A pilot study of twelve PRAC patients who received 2 1/2 years of allergy management revealed no significant dento-facial dimensional change. This study suggests that PRAC with chronic mouthbreathing can alter the development of the midface. Whether allergy therapy can prevent or change this is as yet uncertain.

An evaluation of functional occlusal interferences in orthodontically treated and untreated subjects.

Centric occlusion-generated functional bite registrations failed to show a difference in the number, location or severity of nonworking (balancing) or protrusive functional occlusion contacts between 49 post-orthodontically treated subjects and 27 non-orthodontically treated subjects with ideal static occlusion. Nonworking (balancing) side functional occlusion contacts were present in 85% of the non-orthodontic subjects and 97% of the post-orthodontic subjects. At least within the parameters of this investigation, the lateral and protrusive occlusions of post-orthodontic subjects and comparable non-orthodontic subjects were equivalent. It is important to note that this is a study of incidence. It does not address the meaning or importance of such contacts.

An evaluation of eccentric occlusal contacts in orthodontically treated subjects.

An investigation using Citricon base regulations to record the number and type of centric occlusion-initiated eccentric contacts failed to demonstrate a difference between forty-nine treated orthodontic patients and twenty-seven untreated subjects who were judged to have "ideal" static occlusion. Of the treated and untreated subjects, 97 percent and 85 percent, respectively, had nonworking (balancing) side occlusal contacts. This study illustrates that among the orthodontic patients treated at one university the number of eccentric occlusal contacts is similar to that of a sample of untreated subjects.

Changes in the integumental profile of the chin and lower lip after genioplasty.

The results of a cephalometric study of changes in the soft tissue profiles after horizontal osteotomy for genioplasty were analyzed in 14 subjects. Scatter diagrams relating changes at the soft tissue landmarks of the mandible (point C, LI) to changes at the hard tissue landmark of the pogonion were plotted to illustrate the relationship between the movement of these pairs of landmarks of the lower third of the face. Finally, graphic representation of the regression equations computed from this study gave the clinician a means of predicting skeletal and integumental changes resulting from the surgical procedure under consideration. The following results were obtained. -For all subjects in this study, an anterior change at the hard tissue landmark, Pog, was accompanied by an anterior movement in the soft tissue landmarks of the lower third of the face. The greatest amount of change in the soft tissue occurred at point C, with less anterior change at ILS, and the least at LI. -The response of the soft tissues of the chin had a high correlation with changes at Pog, the corresponding underlying hard tissue landmark. Comparison of changes between them indicated that 1.0-mm change at Pog resulted in approximately 0.8-mm anterior change at point C, the overlying soft tissue landmark. -The response of the soft tissue of the lower lip showed a correlation to changes at Pog. Comparison of changes between them indicated that 1.0 mm-change at Pog resulted in approximately 0.4-mm anterior displacement at LI, the overlying soft tissue landmark. However, the correlation was not sufficiently great to be used in any individual prediction. -The relationship of the response of hard tissues and soft tissues was similar for large and small amounts of surgical movement.