Integumental Contour And Extension PatternsCHARLES J. BURSTONE, D.D.S., M.S.*Indianapolis, IndianaSuperimposed upon a dentoskeletalframework lies a variable soft tissuemass comprising epithelium, connec-tive tissue, and muscle. Variation inthis soft tissue veneer can be an im-portant factor in case analysis, as it in-fluences: ( 1) facial form and esthetics,(2) muscle balance of the orbicularisoris complex and hence, the stabilityof the anterior dental segment.In considering soft tissue, a numberof approaches are possible. Methods ofmeasuring superficial facial contour andthe establishment of standards based onthese methods can be presented.'Similarly dentoskeletal standards canbe established from samples selectedby esthetic rite ria.^ This investigationis concerned with two problems: (1)direct measurement of the soft tissuemass and, (2) differences in integu-mental contour and extension withrespect to sex and maturation.ACCEPTABLE FACE SAMPLESTwo samples, which possessed goodor excellent facial profiles, were select-ed from a group of photographs by apanel of artists.* The only criteria forselection were age, race (Caucasian),and facial form. The younger age sam-ple represented an adolescent groupwith a mean 'age of 14.7 years and arange from 13.4 to 15.6. This includesan age range at which orthodontictreatment is terminated in many in-stances. The second sample, a young`Director of Orthodontics, Indiana Unirers-it!- School of Dentistq-."John Herron Institute of Art, Indianapolis,Indiana.adult group, possessed a mean age of23.8 with a range from 16.5 to 36.3.In terms of orthodontic treatment, thissample reflects the post-retention peri-od. The broad age range of the youngadult sample might be criticized, butthis criticism could be partly temperedby the knowledge that growth changesare not as marked in this group as theywould be in a younger age.The number in each sample and itsdistribution by sex is given in Table I.TABLE I..idolescent l'ou7Lg Adultl\l:Lle 11 3I:ile 15Feni:ile 26 Feiiiale 2 3- -T(,t:tl 37 Total 4 0The reliability of artists choosing asample of this type might be question-ed. Perhaps, their esthetic criteria donot represent the criteria of the generalpopulation. With this in mind, theadolescent sample was rechosen by agroup of housewives. There were nodifferences in opinion concerning facesthat both housewives and artists hadtyped "excellent". The only differenceoccurred in the "good" face category.These substitutions were small in num-ber and did not appreciably alter anyof the mean values that were laterdetermined. This tended to reaffirmthe sampling procedure.The faces of both samples areminimally interpreted and are referredto as "acceptable" rather than "good"or "excellent".93 94BurstoneApril, 1959METHOD OF INTEGUMENTALEXTENSION MEASUREMENTThe basic record for the study wasthe lateral headplate, which was takenucing the Broadbent techniq~e.~ Thecassette was placed as close as possibleto the subject. The lip posture was thatof initial closure, with the mandible incentric position.The development of a consistent, ac-curate, and meaningful method ofmeasurement of the soft tissue masspresents inherent problems. Theseproblems particularly arise in thedimension describing "thickness". Thesoft tissue of the face is quite irregularand variable and does not readily sug-gest planes of reference within the softtissue itself and, therefore, if such planesare to be established, they must utilizedental or skeletal landmarks. There isa lack of uniform correspondence ina vertical plane between skeletal andsoft tissue landmarks (standard devia-tions may `ut: as lalge as 3 iiiKrxtixs).Hence, simple lines connecting soft andhard tissue landmarks would cross thesoft tissue at various angles and wouldnot accurately reflect lip thickness.A compromise method was adopted,which measures the amount of exten-sion of integumental landmarks fromadjacent skeletal points relative to onecommon plane. Since these measure-ments do not exactly reflect "thick-ness" and "length", they are best re-ferred to as horizontal and vertical ex-tensions. The common plane of refer-ence for horizontal extension measure-ments is the nasal floor, and for verticalextension measurements, a perpen-dicular to the nasal floor is utilized.Horizontal extension (Fig. 1A)represents the distance in millimetersbetween a dental or skeletal landmarkand an integumental landmark asmeasured along the nasal floor (a lineconnecting anterior and posterior nasalFig. 1 Iiiteguniental and skeletal land-marks denionstratin? extension measure-menta, A, horizontal extension, B, verticalextension. Skeletal landmarks : 1) subspinale,2) incision superius. 3) incision superius,4) incision inferius, 5) supramentale, 6) po-gonion. Integumental landmarks: A) sub-nasale, B) superior labial sulcus, 0) labralesuperius, D) labrale inferius, E) inferiorlabial sulcus, F) menton, G) glabella,S) stomion.spines) . Seven horizontal extensionreadings are listed below and thedental or skeletal (S) and integumental(I) landmark for each is operation-ally defined.Glabella (I) - det rniined by a tangentto the forehead from a line passingthrough subnasale.Glabella (S) - the intersection of theouter plate of the frontal bone with ah rizontal line (parallcl to nasal floor)drawn from frontal point (1).Subnasale (I) - the point where maxil-lary lip and nasal septum form a definiteangle. If the depression is a gentle curve,subnasale is interpreted as the most con-cave point in this area as measured by aline angled 45 degrees from nasal floor.Subspimale (S) - the deepest point be-tween anterior nasal spine and prosthionrelative to nasal floor.Superiar Labial Sulcus (1) - the deep-est point on the upper lip aa determined Vol. 29, No. 2Extensionby a line drawn from subnasale inclinedSO thait it forms a tangent wit.h labralesuperius.Subspinale (S) - the deepest point be-tween anterior nasal spine and prosthionrelative to nasal floor.Labraze Superius (I) - the mos~ prom-inent point on the upper lip as measuredfrom a perpendicular to nasal floor.Zncision Superius (S) - the most prom-inent point on the maxillary incisor asdetermined by a tangent to the incisorpassing through subspinale.Labrale Znferius (I) - the most prom-inent point on the lower lip as determinedby a perpendicular from nasal floor.Incision Inferius (S) - ithe most anteriorpoint on the lower incisor determinedfrom a line tangant to the chin andmandibular incisor.Inferior Labial Sulcus (I) the most con-cave point as measured by a. line tangentto menton and labrale inferius.Supramentale (S) - deepest point be-tween pogonion and infradentale as deter-mined from a line tangent to lower incisorand pogonion.Menton (I) - most anterior point onchin determined by a line tang2nt to thelower lip and the chin.Pogonion (S) - most anterior point onthe chin as determined from a perpendic-ular to nasal floor.Vertical extension (Fig. 1B) is thedistance in millimeters between a dentalor skeletal and integumental landmarkmeasured along a perpendicular tonasal floor. If the integumental pointPatterns95is superior to the dental or skeletalone, the reading is given a plus sign;if inferior, a minus sign.Superior Labial Sulcus -(I) - thedeepest point on the upper lip as deter-mind by a line drawn from subnasaleinclined so that it forms a tangent withlabrale superius.Subspinale (S) - the deepest point be-tween anterior nasal spine and prosthionrelative to nasal floor.Inferior Labial Sulcus (I) - the mostconcave point as measured by a line tan-gent to menton point and labrals inferius.Stolnion (I) - the juncture in the rnid-line of the upper and lower lips.Supramentale (8) - deepest point be-.tween pogonion and infradentale as de-termined from a line tangent to lowerincisor and the chi.Znoision Superius (S) - the most in-ferior point on he maxillary incisor.INTEGUMENTAL EXTENSION STANDARDSThe preceding method of integu-mental extension analysis was appliedto the adolescent and young adultsamples. Means, standard deviations,and standard errors of mean by sampleand sex are given in Tables I1 and111.The soft tissue mass of the face lyinginferior to subnasale is quite thick incomparison to the mass of the glabellar TABLE I11NTEGUMENTAL EXTENSION VALUES OF ACCEPTABLE ADOLESCENT PROFILESXALES F EMA T, ES~S.E. of S.E. ofExtension Measurewwnts Mean S.D. Mean Mean S.D. Mean P*Glabella .................... 7.0Subnasale .................. .18.7Superior Labial Sulcus ...... 26.2Labrale Superius ............ ,155Labrale Inferius ............ .16.1Inferior Labial Sulcus ....... .12.9Menton .................... .12.8Subspinale-Superior Sulcus ... .-4.4Supramentale-Inferior Sulcus . . 1.3Incision-Stomion ............. 3.11.112.331.611.881.542.202.191.901.692.210.37 6.6 0.82 0.160.78 16.9 1.45 0.290.54 14.7 1.88 0.380.63 12.1 1.83 0.370.51 13.4 1.29 0.260.73 11.6 1.31. 0.260.73 12.2 1.85 0.370.63 -3.4 1.78 0.360.56 1.6 1.94 0.390.74 3.5 1.64 0.3320.05.05.001.001.05.20.20.20.20* t test 96BurstoneApril, I959region. This difference, in part, reflectsthe high degree of development ofthe orbicularis oris complex. The upperlip gradually becomes thinner as onemoves from subnasale to labralesuperius. The horizontal extension atinferior labial sulcus and menton is lessthan any other region of the lower face.Vertical extension averages indicatethat superior labial sulcus lies inferiorto subspinale and inferior labial sulcuslies superior to supramentale. Stomionis positioned about three millimeterssuperior to the tip of the maxillaryincisor.Considerable variation in horizontaland vertical extension values is ob-served in the adolescent and youngadult samples. However, the greatestvariation is found in the lower face,particularly in the lips.Correction of these linear values forenlargement has not been considereddesirab!e. Most clinicians, who mightfind it useful to apply soft tissue stand-ards would not consider it practicalto use correction scales. The similarityin position of landmarks in respect tothe central x-rays and the small lineardimensions tend to minimize error inthe comparison of an individual to thestandard.To facilitate extension analysis, agrid based upon the adolescent accept-able profile sample is presented (Fig.2). The grid is divided into two por-tions with male values at the top andfemale at the bottom. Mean values arelisted above each measurement alongthe center line. Readings greater thanthe mean are plotted to the right andthose less to the left. Standard errorsof the mean and standard deviationsare listed respectively at the right andleft.INTEGUMENTAL EXTENSION VARIATION IN MALOCCLUSIONSMalocclusions exhibit not only mal-relations of teeth but also facial dis-harmony. In part, this disharmony maybe produced by variation in thc softtissue mass. In many instances, the re-vcrsc v;i!! cccur; snft tissur vsiiationmasks a dentoskeletal discrepancy.If an individual is compared with anappropriate age and sex integumentalextension standard, absolute values and~~ ~Glabella .................... 6.2 1.01Subn:isale .................. .19.3 1.74Superior Labial Sulcus ...... ,172 1.83Labrale Superius ........... .15.1 1.92Labrale Inferius ........... .16.3 1.45Inferior Labial Sulcus ...... .11.9 1.24Menton .................... .13.6 1.82Subspinale-Superior Sulcus .. .-6.2 2.08Supramentale-Inferior Sulcus . 1.1 3.21Incision-Stomion ............ 2.3 2.560.2800.4820.5Oi0.6320.4020.3440.5050.5iG0.8900.709~ ~~6.1 0.7813.5 1.6413.8 1.4411.8 1.5413.4 1.6810.9 1.1011.6 1.35-4.5 1.362.5 1.523.7 1.680.1560.3280.2880.3080.3360.2200.2760.2720.3040.33620.001.001.001.001.02.001.01.05.05+ test Vol. 29, No. 2 Extension Patterns 97 I .904 1.690% 2.21kSUBSPI ALE-SUPERIOR ULCUS 0.63SUPRAM NTALE- INFER10 SULCUS 0.56 0.741.3 3. IINCISION - STOMION0I .78 SUBSPI ALE-SLPERIOR SULCUSJ ? 1.62 i.94' SUPRAM NTALE- INFER10 SULCUSI- 0 3.5i.64 I ' '0.360.390.33- 98 BurstoneApril, I959their distance from the mean are notas imPortant as the relationship of one- MALEMEANvalue to another, Considering the rela-tionship of one value to another, read-ings may deviate uniformly from themean (cancellation of variation) orreadings may deviate in opposite direc-tions from the mean (accumulativevariation).Four cases are shown which presentvarying integumental extension pat-terns (Figs. 3, 4, 5 and 6). In case A,a large amount of maxillary horizontalextension is contrasted by a deficiencyof mandibular extension. The ac-cumulative variation between superiorand inferior labial sulci should be noted 5 -0+(Figs. 3 and 4).Case B demonstrates accumulativevariation between horizontal extensionvalues of subnasale and menton (8.7minimizes the total facial convexity thatis inherent in the skeletal pattern.inferior to its normal position (Figs.3 and 4).FEMALCMEANmillimeters). This soft tissue variationSuperior labia! yr;!cr;s LeF, c.nsiderab!yMENTON-34 0SUPRAM NTALYINFERIO SULCUS0 3s..L5 -0+ 5Fig. 4below, are plotted on grid.Values from case A, above, and B,A boy with a repaired unilateral cleftof the lip is seen in Case C. Lip masshas been noticeably reduced, especially mandibular contour is benefited byFig. 3 Case A, a. large amount of maxil-lary horizontal extension is contrasted by a decreased horizontal extension atdeficiency of mandibular extension. Case B, labralc inferius and increased extensiondemonstrates accumulative Variation between at menton. superior and inferior sulcihorizontal extension values at subnnsale andmenton (8.7 mm.). are atypically positioned in the verticalIin the region of labrale superius. Labio- Vol. 29. No. 2Extension Patterns99aFig. 5 Case C demonstrates a repairedunilateral cleft of the lip. Uase D, the pro-file possesses slightly greater horizontal ex-tension than the standard in bhe maxillaryreglon. Extremely small amounts of softtissue extension are seen around the inferiorlabial sulcus and menton.plane (Figs. 5 and 6).The profile in case D possesses slight-ly greater horizontal extension than thestandard in the maxillary region. Theincreased value of labrale inferius canbe partly attributed to deflection of thelower lip produced by the overjet. Ex-tremely small amounts of soft tissue ex-tension are seen around the inferiorlabial sulcus and menton (Figs. 5 andIn evaluating extension variation,particularly in the horizontal plane, anumber of factors have to be consider-ed. Not all of the variation need beproduced by inherent structural varia-tion in the soft tissue mass. For exampleFig. 7 demonstrates two individuals withthe mandible in centric position. Thedotted line indicates soft tissue formwith the lips relaxed and the solidline represents a closed lip position. Incase B, little space is present betweenthe lips in their relaxed state (inter-labial gap equals 1 millimeter). By con-6) *- MALEMEAN5 -0+FEMALEMEAN5 -0+ 5Fig. 6below, are plotted on the grid.Values from case C, above, and D,trast in case A, the patient exhibits alarge interlabial gap (12 millimeters)associated with a vertical labial in-sufficiency. In an effort to produce lipclosure a marked effort is required.The ensuing muscular imbalance altersthe soft tissue extension pattern. Like-wise, in excess lip length cases (vertical 100Burstone April, 19591IFig. 7 Integumental extensions as influ-c~nc~ed by postural variation : relaxed lipposition - ilottcd line, initi:il lip closure -solid line, A) ni:irked soft tissue change as-socixtcd with rertictl labial insnfficieney,R) nriniin;il cliange in soft tissue ni:\ss.labial redundancy) the lips will pro-trude and thereby increase the exten-sion pattrrn.%me \:,riation i\ assnci;lted with themethod itself. Changing planes ofreference (used for measurement andselection of landmarks) and variationin the relative position of landmarksshould be considered as a possiblesource of variation.SEX DIFFERENCES IN EXTENSIONThe soft tissue mass of the facedemonstrates sex differences which arereflected in both adolescent and youngadult samples, but are most marked inthe latter. (Tables I1 and 111)In the young adult sample, there isno apparent difference between thesexes in the thickness of soft tissuecovering the forehead. By contrast, inthe lower face where the developmentof the orbicularis oris complex exertsits influence, significant differences areto be found. The soft tissue mass ofall areas from subnasale to menton arethicker in the male. In particular,horizontal values in the upper lip aver-age three to four millimeters greaterin the male than in the female.Vertical differences in the upper lipcan be observed with respect to theskeletal points, subspinale and incision.In the male, superior labial sulcus andstomion are found to be in a more in-ferior position.MATURATION CHANGES IN THE INT,EGUMENTAL PROFILEThe maturation of integumental ex-tension and contour from the adolescentto the young adult has been studied ona cross-sectional basis utilizing two ac-ceptable face samples. This type of pro-cedure is useful in detecting uni-directional changes but tends to maskbidirectional variation. This, added tothe danger of sampling error, suggeststhat these cross-sectional studies shouldbe followed by longitudinal ones.Considering horizontal extension(even though some significant differ-ences can be demonstrated), the levelsof confidence and the small magnitudeof the mean differences suggest thatlongitudinal methods could best studythe problem.In the direction of vertical extension,it is seen that superior labial sulcus be-comes more inferior in its relation tosubnasale with age (Male: p .05, Fe-male: p .02).A method for measuring the in-tegumental profile by angular meanshas been previously described. Readingsare of two types: inclination angles,(profile components relative to nasalfloor) and contour angles (profile com-ponents relative to each other) .2Table IV gives the means, standarddeviations and probabilities for the twosamples. For graphic purposes, themeans of the adult sample are plottedon the adobescent grid (Fig. 8).Lower facial inclination is sig-nificantly greater in the adolescentgroup. This is true for both anterior Vol. 29, No. 2Extensionand posterior measurements. Man-dibular and interlabial inclinations aresimilarly greater in the younger ageperiod. This difference could be partlyexplained by an increase in the man-dibular prominence as part of thematuration process.The protrusion of the upper lip fromthe sulcus (superior labial inclination)increases with age as contrasted withthe curl of the lower lip (inferior labialinclination) which shows a significantdecrease in the young adult sample.The prominence of the chin from theinferior sulcus shows an increase in theolder group.With reference to the contour anglesof the face a significant difference isseen in only one, total facial contour.The total face becomes less convex withmaturation.Even though many inclination anglesPatterns 101in the lower face demonstrate signif-icant differences, contour angles formedin this area do not show significantdifferences. Labiomandibular contourremains fairly constant. Cross-sec-tional studies in younger age groupsfurther suggest that the labioman-dibular angle changes minimally withgrowth and maturation.' Maxilloman-dibular contour, a measurement offacial convexity below the nose, demon-strates no significant difference. It ap-pears, therefore, that there is no evi-dence to sugqest marked flattening ofthe lower face in the post adolescentperiod.Since the significant differences (ortheir lack) between the two samplesrepresent average maturation changes,individual variation is not taken intoconsideration. Hence, attempts to es-timate individual integumental changeson the basis of these generalizations~_ ~- _~.~~~ ~~~ __(XAG) Upper Facial Inc. . . . . . . -5.7 3.5 -6.5 3.2 a.bove 0.05(XAF) Loser Facial Ine. 4.0 4.8 4.0 0.01(XBE) Lower Facial Inc. 4.8 11.7 4.2 0.01(XAC) Maxillary In?. . . . . 7.6 -4.0 6.7 nhove 0.0,7 0.01(SDF) Mnndihulnr Tnc. . . . . . . . . 11.5 2.:) 7.5 ;).;)(SO) lnterlahial Inr. . . . . . . . , . 11.7 5.0 8.0 5.0 0.01(SAR) Snbn:isnl Tnc. . . . . . . . . . . 17.1 7.0 16.0 7.4 :i~mrr 0.05(SRC) Superior Lnhinl Inc. . . . . -22.G S.7 -27.0 9.5 0.N(XT)E) lnfrrior Lnhi:\l Inr. . . . . . 47.5 9.6 41 .9 9.2 0.02(XEF) Supramental Inc. . . . . . . . -1 2.9 (is -1 6.1 3.7 0.01(CAB3) Total Facial Con. . 3.8 11.3 4.1 0.01( ACDF) 3~nxillo-~Im1~lib~1lnr Con. 13.5 S.9 11.5 6.5 nhore 0.05(C!DF) liabio-~~:uidihnlur Con. . . 0.2 i.0 -O..i 6.0 ai)ovc 0.05(ABC) Nmi1l:iry Snlcus Con. . . . 3!).7 93 -13.1 10.0 above 0.05(DEI?) 3fandibdar Snlcus Con. . 59.7 11.4 5S.0 11.7 ahorc 0.05----+p - .0.i or less drnotcs significant tlifferenccs l)ct:\veeii :uloles~cnt :ind ndnlt. integumcntnl:~nglcs. 3 INTEGUMENTAL PROFILE GRID OF ACCEPTABLE ADOLESCENT FACES9mMEAN RANGEWE.E010Ps -.2cd9 Vol. 29, No. 2Extension Patterns103should be made with considerablereservation.DISCUSSIONAn awareness of integumental exten-sion and contour is an essential elementof case analysis. Since considerablevariation may occur in the soft tissuemas of the face, treatment based onarbitrary dentoskeletal standards can-not be expected to consistently producedesirable facial form. In many indi-viduals application of an absolutestandard will lead to increased facialdisharmony or the substitution of onetype of disharmony for another. Sincethe soft tissues as well as dentoskeletalstructures demonstrate variation, bothshould be considered in establishing theanteropostero-positioning of the dentureand the axial inclinations of the an-terior teeth.Concomitant with hard tissuechanges during treatment, a redistribu-tion of soft tissue may occur. Soft tissuechanges become evident if horizontaland vertical extension values are com-pared before and after treatment (Fig.9 and 10). The alteration of the softtissue mass is in part postural, reflectinga change in the manner of lip closureand in part, the result of growth. Fur-ther investigations are needed to deter-mine if altering dentoskeletal structuresor myofunctional therapy can inherent-ly change the soft tissue mass of theface (non-postural alteration).In an orthodontic case, esthetics isclosely related to stability. Rarelyshould facial esthetics be achieved atthe expense of denture stability. Sta-bility and esthetics need not be sep-arate objectives, for those same mus-cular imbalances that may operate toproduce denture instability may also beresponsible for disharmony in facialcontour.The present study is basically staticIFig. 9 Integumental extension ohanges in-cident to orthodontic treatment, A) pre-itrentment, R) pnsttmatnient.in nature. Future functional inves-tigations are needed to relate varia-tion in soft tissue mass with the muscleactivity of the orbicularis oris com-plex.FEMALE5 -0+ 5Fig. 10 Integumental extension changes ofpatient shown in Fig. 9. Dotted line - pre-treatment,, solid line - postt-rratment. 104 Burstone April, 1959SUMMARY1. Utilizing the oriented lateral '.headplate, a method of measuring in-tegumental (vertical and horizontal) 2.extension was presented.2. Integumental extension standardsbased on artist-chosen samples were R.established for adolescent and young3. Malocclusions exhibited con-siderable variation in integumental ex-tension from the means of the stan- *;.dards. If accumulative variation weremeasured, deviations from the averageincreased in value.4. Sex differences were noted inintegumental extension. Areas inferiorto the nose in the male, generally, hadgreater horizontal extension of soft tis-sue.5. Maturational changes in the in-tegumental profile from adolescence tothe young adult were considered. Sig-nificant differences were demonstratedin: lower facial, --- --- J1L..l,... . Illdlluluulal, iritcr-labial, superior labial, inferior labial,and supramental inclinations. The onlycontour angle to show a significant dif-ference was total facial contour whichtended to flatten with age.6. Increasing evidence suggests thatan awareness of variation in the softtissue mass should become an integralpart of orthodontic case analysis,adult groups. 4.REFEREXCESStoner, M. M.: Photometric Analysis OfThe Facial Profile. Am. J. Ortlto., 41 :453-469, June, 1955.Burstone, C. J.: The Integumental Pro-file, Ain. J. Ortho., 44:l 25, January,1958.Riedcl, R. A. : Analysis Of Dento-facialRelntionsliips, Ain. J. OI'tlro., 43:703-119,February, 1937.Broadbent, R. Holly : Bolton Standardsand Techiqrie In Orthodontic Praotitiee,An,qZr: Ortho., 7 :209-223, 1037.Burstone, C. .J. : U~ipnblislied Dnta.