An Evaluation of the Integumental Facial Pro- file and It's Relation to Underlying Structures

Aims : To evaluate the correlations between the skeletal measurements and soft tissue measurements in males and females. Materials and Methods: Eighty students (40 males and 40 females) were selected aged (12-14) years with class I normal occlusion from intermediate schools in Mosul City . A standardized lateral cephalometric radiograph was taken for each student, eighteen variables, 9 angular (6 skeletal and 3 soft tissue ) and 9 linear (3 skeletal and 6 soft tissue) were used in this study. Results: In males, angle of facial convexity positively correlated with angle of skeletal convexity and negatively with the angle describes the relationship of the maxillary and mandibular bases in the sagittal planes.The length of mandibular corpus was positively correlated with upper lip thickness, lower lip thickness at labral inferius and upper lip height . Upper lip thickness at labral superius was positively correlated with angle defines the anteroposterior position of maxilla in relation to anterior cranial base and angle indicates the anteroposterior position of the mandible in relation to the anterior cranial base.Lower lip height was positively correlated with the mandibular plane angle .In females, angle of facial convexity was positively correlated with angle of skeletal convexity and negatively with the angle describes the relationship of the maxillary and mandibular bases in the sagittal planes. The angle measures the protrusion of upper lip relative to the inferior border of the nose was negatively correlated with angle of skeletal convexity and mandibular length and positively with angle describes the relationship of the maxillary and mandibular bases in the sagittal planes.Angle of skeletal convexity was positively correlated with upper lip thickness at point A and upper lip thickness at labral superius . The mandibular plane angle was positively correlated with lower lip height. The angle describes the relationship of the maxillary and mandibular bases in the sagittal planes was positively correlated with labiomental angle and negatively with upper lip thickness at labral superius . The mandibular length was negatively correlated with labiomental angle and positively with upper lip thickness at point A , An Evaluation of the Integumental Facial Profile and It's Relation to Underlying Structures ISSN: 1812–1217 www.rafidaindentj.net Al – Rafidain Dent J


ABSTRACT
Aims : To evaluate the correlations between the skeletal measurements and soft tissue measurements in males and females. Materials and Methods: Eighty students (40 males and 40 females) were selected aged (12)(13)(14) years with class I normal occlusion from intermediate schools in Mosul City . A standardized lateral cephalometric radiograph was taken for each student, eighteen variables, 9 angular (6 skeletal and 3 soft tissue ) and 9 linear (3 skeletal and 6 soft tissue) were used in this study. Results: In males, angle of facial convexity positively correlated with angle of skeletal convexity and negatively with the angle describes the relationship of the maxillary and mandibular bases in the sagittal planes.The length of mandibular corpus was positively correlated with upper lip thickness, lower lip thickness at labral inferius and upper lip height . Upper lip thickness at labral superius was positively correlated with angle defines the anteroposterior position of maxilla in relation to anterior cranial base and angle indicates the anteroposterior position of the mandible in relation to the anterior cranial base.Lower lip height was positively correlated with the mandibular plane angle .In females, angle of facial convexity was positively correlated with angle of skeletal convexity and negatively with the angle describes the relationship of the maxillary and mandibular bases in the sagittal planes. The angle measures the protrusion of upper lip relative to the inferior border of the nose was negatively correlated with angle of skeletal convexity and mandibular length and positively with angle describes the relationship of the maxillary and mandibular bases in the sagittal planes.Angle of skeletal convexity was positively correlated with upper lip thickness at point A and upper lip thickness at labral superius . The mandibular plane angle was positively correlated with lower lip height. The angle describes the relationship of the maxillary and mandibular bases in the sagittal planes was positively correlated with labiomental angle and negatively with upper lip thickness at labral superius . The mandibular length was negatively correlated with labiomental angle and positively with upper lip thickness at point A ,

INTRODUCTION
A major orthodontic treatment goal is to improve facial esthetics and maintain or improve the labial contours of the upper and lower lips. (1,2) Facial and dental esthetics has become even increasingly important during the last decade. Recently, the field of orthodontics has experienced a paradigm shift to focus more on esthetics , with specific emphasis on soft tissues around the mouth. Evaluation of facial esthetics is considered to be subjective , because balance and harmony of facial components do not necessarily mean an attractive face. (3) Judge race or ethnicity and patient race or ethnicity and sex significantly influence lay person's standards for lip profile esthetics, (4,5) also the facial appearance is fundamental for communication and interaction with the environment. (6) One of the most important components of orthodontic diagnosis and treatment planning is the evaluation of the patient's soft tissue profile. (7) A harmonious soft tissue profile, an important treatment goal in orthodontics is sometimes difficult to achieve, partly because the soft tissue overlying the teeth and bones is highly variable in it's thickness. These variations result not only from imbalance of the dental and skeletal structures but from individual variations in the thickness and tension of the soft tissues. (8) Attempts to gain lip closure made by patients with protrusion of the maxillary or mandibular incisors result in lip strain accompanied by hyperactive mentalis function and evaluation of the integument of the chin . orthodontic treatment improves lip form and increases the soft tissue chin thickness. (9,10) Traditionally, it has been assumed that facial contours primarily the result of underlying hard tissue positioning and the subsequent soft tissue drape . Numerous studies are available that illustrate the fact that soft tissues vary considerably in thickness and undergo changes that are regionally independent of hard tissue growth. (11,12) Configural relationships among the constituent features of a face can influence about external facial proportions. (13) The two aspects of soft tissue assessment which have received the most attention are the relationships between the soft tissue and dentoskeletal variables in normal occlusion and the changes in soft tissue associated with therapeutic changes in dentoskeletal structures. (14) Soft tissues might have their own inherent architecture and that the midfacial soft tissue form and position appear to be less dependent on underlying hard tissues than for the lower facial soft tissue variables. (15) Blanchette et al., (11) concluded that the soft tissue attempt to compensate for extremes in vertical skeletal support in those persons with low and short vertical facial patterns. (11) Kasai (8) reported that a longer lower facial height and protruded lower incisors were associated with a thicker upper lip and soft tissue B, and that a larger ANB angle was associated with thicker soft tissue chins. (8) Cephalometric analysis has proven to be a useful tool in the diagnosis , evaluation and treatment planning of patients undergoing orthodontic treatment and / or orthognathic surgery and to evaluate treatment results. (16) The aim of the study was to evaluate the correlations between the skeletal and soft tissue measurements in males and females.

MATERIALS AND METHODS
The sample of this study was collected from intermediate schools in the center of Mosul City. 80 students (40 males and 40 females) were selected aged (12)(13)(14) years with class I normal occlusion.
The criteria of sample selection : 1.Full complement of permanent teeth excluding the third molars and normal occlusion with bilateral class I molar and canine relationships. (17) 2.Not more than 2mm crowding. (17) 3.Normal overjet and overbite (1-4 mm). (18) 4.Minor rotations and / or spacing (less than 1mm). (19) 5.No previous orthodontic treatment , maxillofacial or plastic surgery. (20) Each subject was radiographed in a standing position by positioning the subject's head in the cephalostat with the left side of the face toward the x-ray tube.The head was then adjusted so that the Frankfort horizontal plane is parallel to the floor.Each subject was instructed to close the teeth in maximum intercuspation with the lips in contact and not to move until exposure was completed.
The lateral cephalometric radiographs from the selected individuals were traced , and reference points and planes were then obtained, 9 angular (6 skeletal and 3 soft tissue) and 9 linear (3 skeletal and 6 soft tissue ) measurements illustrated in Figures (1) and (2) were constructed . * Skeletal measurements : Angular skeletal measurements include : FH/NPog : Facial angle : It is formed by the intersection of the Frankfort horizontal and facial plane. (21) NAPog : Angle of convexity. (8) FH/GoMe : This is a measure of the relationship between the Frankfort plane and the lower border of the mandible. (21) SNA, SNB, ANB. (22) *Linear skeletal measurements : Ar-Gn, (23) Go-Gn, (24) ANS-PNS. (25) *Soft tissue measurements : -Angular measurements: -GL'SNPog : Angle of facial convexity. (26) -CMSNLS : This angle measure the protrusion of upper lip relative to the inferior border of the nose. (23) -LISMPog : Labiomental angle : from labral inferius to soft tissue supramental B and soft tissue pogonion. (27) *Linear measurements : -ULTHICKA : Upper lip thickness at point A (A-A') : This was measured between point A and projected A. (11,23) -ULTHICKLS : Upper lip thickness at labrale superius (LS-LS') : This was measured between labrale superius and projected labrale superius. (11,23) -LLTHICKLI : Lower lip thickness (LI-LI') . It was measured between labrale inferius and projected labrale inferius. (11,23) -CHIN : Soft tissue thickness at the chin (Pogs-Pogs') : This was measured between soft tissue pogonion and projected soft tissue pogonion. (11,23) -ULHEIGHT : Upper lip height : This was measured as the perpendicular distance from stomion superius to the palatal plane. (28) -LLHEIGHT : Lower lip height : This was measured as the perpendicular distance from stomion inferius to the mandibular plane (Go-Me). (28) Analysis of data by using SPSS program was done including descriptive statistics (means and standard deviations) of the skeletal and soft tissue variables (angular and linear measurements) for males, females and total sample. Pearson's correlation coefficients between skeletal and soft tissue variables were done for males and females separately. The ''r'' value is described as significant at (p< 0.05)and highly significant at (p<0.01).

RESULTS
Tables (1,2) show the descriptions of the skeletal and soft tissue variables (angular and linear measurements) for both sexes and total sample .The correlation coefficients of the soft tissue with skeletal variables for males and females were described in tables (3,4) . Some of them showed a positive correlation s, while others showed a negative one.      In males, as shown in Table (3) GL'SNPog was positively correlated with NAPog and negatively with ANB angles.Go-Gn line was positively correlated with ULTHICKA , LLTHICKLI and UL-HEIGHT.ULTHICKLS was positively correlated with SNA and SNB angles.LLHEIGHT was positively correlated with FH/GoMe.In females, as shown in Table (

DISCUSSION
NAPog was highly significant and positively correlated with the GL'SNPog in males and females , in addition it's positively correlated with the CMSNLS ,ULTHICKA and ULTHICKLS in females only .
The relation of angle of convexity NAPog with the convexity of soft tissue profile similar to the results achieved by berglind et al. (16) This mean that the convexity of the soft tissue profile is closely related to the underlying NAPog .FH/GoMe angle was highly significant and positively correlated with the lower lip height in both sexes . The soft tissues attempt to compensate for extremes in vertical skeletal support in those persons with long and short vertical facial patterns ,the boys and girls with long vertical patterns showed a greater vertical height of the lower lip when compared with those of short vertical patterns , also the vertical height of the lower lip has been a compensatory mechanism for the subjects to perform a lip seal. (11) The SNA and SNB angles are significant and positively correlated with UL-THICKLS in males only which comes in agreement with Kasai (8) who stated that the relation ships between upper and lower jaw were associated with the thickness of the upper lip and of soft tissue chin. The differences between males and females is due to the differences develop in the size , thickness and position of the lips and chin as they approach maturity . (29) Nanda (30) found that female's upper lip thickness and chin soft tissue decreased with age, but the lower lip increased. These soft tissue changes in females , taken together with the minor mandibular skeletal changes resulted with age and the profile not becoming straighter .
Concerning ANB angle, our results showed that this angle was highly significant and negatively correlated with GL'SNPog angle in both sexes, this angle also positively correlated with CMSNLS and LISMPog angles and negatively with ULTHICKLS in females only,due to the structural and growth differences between males and females.
Our results showed that as the ANB angle increase, the skeletal facial convexity will decrease, so that GL'SNPog which is the angle of soft tissue convexity will decrease and vise versa.
Kasai (8) stated that the ANB angle provide orthodontists with important information and a small ANB angle will increase the facial convexity and associated with a smaller pogonion thickness and a relatively thick upper lip.
The Ar-Gn line has no significant correlation with the soft tissue variables in males, while in females it was significantly negatively correlated with CMSNLS and LISMPog and positively with UL-THICK A, ULTHICKLS , LLTHICKLI , CHIN , ULHEIGHT and LLHEIGHT.
The relationship of the lower jaw and the upper lip and soft tissue chin are similar to that found by Kasai. (8) Go-Gn line is highly significant and positively correlated with ULTHICKA, LLTHICKLI and ULHEIGHT in males , while in females it is negatively correlated with LISMPog and positively with UL-THICKA and ULTHICKLS.
The relationship between the length of the mandibular corpus and lip thickness are present to provide a more normal facial appearance. (11) ANS-PNS has no significant relationship with the soft tissue variables in males , while in females it was highly significant and positively correlated with UL-THICKA , ULTHICKLS and LLTHICK-LI.Increasing the maxillary length in females will lead to increase in the thickness of upper and lower lips.The maxilla maintained a constant relationship and presented a co-ordinated forward displacement relative to the cranial base.The maxilla is at least two years a head in its relative size in comparison to the mandible,in preadolescent females. (25) In general, there were no consistent, good correlations between soft tissue structures and the underlying hard tissue structures. (23) There are many correlation of the hard and soft tissue variables demonstrated a considerable degree of variability between males and females the reason is unknown. (31)

CONCLUSION
The relationships between the hard tissue structures and soft tissue profiles are variable. For some variables, hard and soft tissue structure are closely related (positively or negatively), but some are independent because the characteristics of the soft tissues are influenced by their length, thickness, and functional aspects such as tissue tension.