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Prosthetic management of large nasal septal defectsHussein S. Zaki, DDS, MS, a and Eugene N. Myers, M D bUniversity of Pittsburgh, School of Dental Medicine, Pittsburgh, Pa.Large nasa l sep ta l d e fec t is de f ine d as a de fec t tha t exceeds in s ize a s t r e tched n os t r i l . La rge nasa lseptal d e f e c t s c a n n o t b e c l o s e d by ha rd ac ry l ic r e s in nasa l sep ta l ob tur a tor s because of access andp a th - o f - i n s e r t i o n p r o b l e m s . H o w e v e r , o b tu r a t i o n c a n b e a ch i e v ed b y c o n s t r u c t i o n o f a n a s a l s t e n ttha t f i t s in to o ne o f the nasa l cavit ie s. This a r t ic le desc r ibes a proc edur e used to manage a la rgen a s a l s e p t a l d e f e c t w i th a n i n t r a n a s a l h e a t - p r o c e s s e d a c r y l i c r es i n s ten t . Th e media l wa l l o f thes t e n t ind i rec t ly a l lows for the pa r t i t io n o f the two nasa l cavi tie s. The s ten t i s r end ered pa te n t toa l l o w f o r c o m f o r t a b l e b r e a th in g . T h e im p r e s s io n m a k in g a n d c o n s t r u c t i o n o f t h e s e s te n t s i s n o tdif f icu l t . T h e s e n a s a l s t e n t s ind i rec t ly sepa ra te the two nasa l cavit ie s and e f fec t ive ob tura t ion ofla rge nasa l sep ta l de fec ts i s achieved . ( J P ros the t Dent 1997;77:335-8 . )

In h e f ie l d o f r h i n o l o g y t h e s y m p t o m c o m p l e x o fs e pt al p e r f o r a t io n is o n e o f t h e m o s t t r o u b l e s o m e ) T h esy m p to m c o m p le x o f u n c o r r e c t e d n a sa l s e p ta l d e fe c t sinc lude ep isodes o f ep is tax is , pos tnasa l d ischa rge , rh in-or rhea , a i r tu rbulen ce , and m ucus c rus t ing . Pa t ien ts wi thnasa l sep ta l pe r fora t i ons usua l ly com pla in o f nasa l dry-ness , whis t l ing o n insp i ra t ion , excess ive mucu s c rus t in g ,and ep is tax is . 2-7 Th e im po r tan ce of nasa l sep ta l d e fec tsv a ri es i n m o s t c ases i n d i r e c t p r o p o r t i o n t o t h e e t i o lo g i cf a c to rs p r o d u c in g i t . T h e e t i o lo g y o f na sal s e p t al p e r f o -ra t ion i s mo re o f ten due to loca l f ac tor s than t o sys temicc o m p l i c a t i o n s . L o c a l c o m p l i c a t i o n s a f t e r s e pt a l su r g e r yor in t ranasa l t r auma 2,3 a re amo ng the co mm on causes ofn a sa l s e p t al p e r f o r a t i o n . Ma n y p a t i e n t s h a v e p r e v io u s lyu n d e r g o n e s u b m u c o u s r e s e c ti o n t o c o r r e c t a d e v i a te dse p tu m . 2 I n t r a n a sa l t r a u m a in c lu d e s n o se p i c k in g a n dth e u se o f c a u t e r y o r c a u s t ic s o n b o th s id e s o f t h e a n t e -r ior nasa l sep tum to t r ea t ep is tax is . Loca l exposure tococa ine ; i r r i tan ts such as l ime , ta r , and p i tch ; ca lc iumnitra te ; sulfur ic acid; arsenicals; sa lt; and glass and c hro-m ic a c id f u m e s m a y c a u se s e p t a l p e r f o r a t i o n s .

In a ser ie s of 45 pa t ien ts exa min ed by Kern e t a l. 4 thecause of nasa l sep ta l pe r fora t ions co uld no t be d isc e rnedf o r al l p a t i e n ts . H o w e v e r , t h e a u th o r s i n d i c a t e d t h a t t h ep e r f o r a t i o n w a s r e l a te d t o n o se p i c k in g ( 8 p a t i e n t s ), e x -t e r n a l t r a u m a ( 6 p a t i e n t s ), s e p ta l su r g e r y c o m p l i c a t i o n s(14 pa t ien ts ) , cau te ry for ep is tax is (3 pa t ien ts ) , and lu-pus e ry th ematosu s (1 pa t ien t ) and sa rcoidos is (1 pa t ien t ) .

R a r e ly d o e s n a sa l s e p t al p e r f o r a t i o n o c c u r a s a c o m -pl ica t ion of som e sys temic d isease . Snyde r e t a l. s r epor te do n tw o p a t i e n t s w i th n a sa l s e p ta l p e r f o r a t i o n s r e su l t i n gf r o m sy s t e m ic l up u s e r y th e m a to su s a d d in g t o s e v e n p re -v io u s ly r e p o r t e d c ase s in t h e l i t e r atu r e . T h e y a l so c o n -c lu d e d th a t a ll n in e r e p o r t e d c a se s sh o w e d c e r t a in c o m -m o n c h a r ac t e ri s t ic s . S e p t al p e r f o r a t i o n a n d e p i so d e s o f

aAssociate Professor of Prosthodontics and D irec tor of Maxillofacia[Prosthod ontic Program.bProfessor and Chairman of O tolaryng ology, Unive rsity of PittsburghMedical Center.

epis tax is became c l in ica l ly ev ide nt dur i ng an exace rba -t ion seve ral mo nth s to yea r s a f te r the d iagnos is o f sys-temic lupus e ry thematosu s . R heum atoid a r thri t i s, 6 syphi -l is , t u b e r c u lo s i s , t y p h o id , a n d d ip h th e r i a a r e d e sc r ib e da s o th e r sy s t e m ic ca u se s . W i th e x a c e r b a t i o n o f t h e u n -d e r ly in g sy s t em ic d i se a se , t h e p e r f o r a t i o n s t e n d t o e n -la rge and ep is tax is i s a cons ta n t in i t ia l symp tom .

Surgica l or mechanica l o b tur a t ion of these de fec ts wi l lhe lp a l lev iate the pro blem of b leeding and mu cus c rus t -ing and wi l l add grea t ly to the co mfo r t of pa tien ts . At-tempt s a t surg ica l c losure have inc luded the use of mu-cosal flaps,8 septal shorten ing, 1 a com posit e f lee graf t f romthe an te r io r end of the midd le turb ina te and fascia ,9 andf ree pe r ic ran ium autogra f t in g wi th c ran ia l pe r ios teum. 2The major drawback in surg ica l c losure i s a s igni f icantbreakd own a t the repa i r si te. This has led to the recom -me nda t ion of no surg ica l r epa ir , e spec ia l ly in ca r t i lag i -nous pe r fora t ions wi th hea led nasa l margins, l P ros the t icclosure of the a nter io r nasal septal perforat ion is the treat-me nt of choice in mo st of these cases . ~ lqs

Mech anica l c losure of the nasa l sep ta l de fec t by a r ti f i -c ial means has pro ved to be a safe r and m ore pred ic tab lea p p r o a c h t h a n su r g ic a l t r e a tm e n t h a s . S o m e c l i n ic i an shave made tw o-dimens iona l t r ac ings of the de fec t to f ab-r i ca t e a n o b tu r a to r . T h e u se o f b lo t t i n g p a p e r t o so a k u pm u c u s , e x c e p t i n t h e a r ea o f p e r f o r a t i o n , w a s u se d t od e t e r m i n e t h e o u t l i n e o f t he d e f e c t ) 3 T h e d r y p a r t w a scut o ut and p laced o ver a p iece of sof t Si las t ic s i l iconer u b b e r ( D o w C o m i n g C o r p . ) s h e et i n g ap p r o x im a t e ly 4to 5 m m in t h i c k n e s s . T h i s sh e e t w a s t h e n t r im m e d toform the S i la s tic s i l icone rub ber but to n . Kern e t a l.4 useda p i ec e o f p a p e r i n o n e n a sa l c a v i ty a n d o u t l i n e d t h em a r g in s o f t h e p e r f o r a t i o n i n t h e o th e r c a v i ty w i th acot ton ba ll d ipped in th imerosa l . This templa te was usedto han d ca rve a nasal bu t to n f ro m medica l -grad e S i la s tics i l icone rubbe r .

C o n s t r u c t i n g t h e n a sa l s e p t a l o b tu r a to r f r o m a n a c -tu a l im p r e s s io n o f t h e d e f e c t h as p r o v e d to b e t h e m o s tlogical ap pro ach in ma nag in g these defects . 7,I2,14,1s Na-sal s ep t a l o b tu r a to r s a r e c o n s t r u c t e d o f e i t h e r m e d ic al -

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Fig. 1. Examination of nasal septal defect with lighted oto-scope and nasal speculum.

grade Silastic silicone rubber or heat-processed acrylicresin. Both materials are biocompatible; however, medi-cal-grade Silastic silicone rubber cannot be highly pol-ished and it is porous and friable. These inheren t prob-lems of silicone may lead to sorption of fluids, irritationof tissues from adhesion o f mucus crust, and tearing o fthe material. In contrast, heat-processed acrylic resin canbe high ly polished, has less tendency for water sorption,and mucus crust seldom adheres to its highly polishedsurface.The main disadvantage of constructing nasal septalobturator s from heat-processed acrylic resin is its lackof flexibility. For septal defects that are larger than thestretched nostril, insertion of the rigid heat-processedacrylic resin obtur ator is often impossible and construc-tion of a rigid acrylic resin nasal septal obturator is pre-cluded. In an attempt to support collapsed alae of thenose, Young 16 used hollow heat-processed intranasal in-serts. These inserts were construc ted by the use of low-heat modeling plastic with an impression wax surface.Each impression covered an area of approximately 2 cminto each nostril. The impressions were invested and pro-cessed in clear polymethyl methacrylate. The final acrylicresin block was hollowed out to provide a patent nasalairway. The internal surface of the stent was highly pol-ished to reduce mucus adhesion to the surface. Seals etal) 7 reviewed the indications, impression techniques, andlaboratory procedures for different clinical situations thatrequired intranasal prostheses, splints, and stents. T heyconcluded that, al though they presented techniques formanaging com mon clinical problems, a unique clinicalsituation may arise. Heat-processed acrylic resin con-formers were used ~8 to maintain structural support offacial tissue that was injured from trauma or altered bysurgical treatment . Ho lt and Pare118 fabricated a two-piece conformer joined together in situ by Velcro inter-locldng (Velcro USA, Inc.) inserts to prosthetically re-place the lost nasal septum.The purpose o f this article was to present a technique

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Fig. 2. Diagramm atic representatio n of nasal cavity in sagittalsection. 1, Hypophysis; 2, sphenoid sinus; 3, perpendicularplate of ethmoid; 4, nasa[ spine of frontal bone; 5, nasal sep-tal cartilage; 6, nasal vestibule; 7, maxillae; 8, vomer; 9, ir-regular large nasal septal defect.used to manage a large nasal septal defect with an intra-nasal heat-processed acrylic resin stent.T E C H N I Q U EThe examination of the nasal septal defect (Fig. 1) isdone by placing a nasal speculum in one nostril and alighted otoscope or fiberoptic light in the other nostril.The extent and configuration of the defect (Fig. 2) andproper identification of the remaining structures shouldbe determined before any attempt to make the impres-sion. It is helpful to aspirate mucus crusting before finaldetermination of the defect. If the defect is found to begrossly larger than the stretched nares, the use of a rigidheat-processed acrylic resin nasal septal obturator willbe precluded. The defect can be indirectly obturated byuse of a hollow intranasal stent in one of the nasal cavi-ties. The medial wall of the stent will prosthetically re-place the missing part of the nasal septum.

An impression o f the nasal cavity is made with RTVsilicone (Silicone Inc., Hig h Point , N.C.). Immediatelyafter the silicone is mixed, one or two cotton-t ipped ap-plicators are wetted t horoughly with the silicone. Thiswill prevent separation of the silicone from the cotton -tipped applicators during removal of the final impres-sion. The nasal speculum is used to widely open thenostril. The applicators are placed passively through thecontralateral nostril into the nasal cavity without touch-ing any of its walls. The cotton-tipped applicators shouldbe visible through the speculum and the defect. A dis-posable syringe (Monojet 4/ 12 , Sherwood Medical, St.Louis, Mo.) is used to inject the silicone impressionmaterial into the opposite nasal cavity (Fig. 3.). A lubri-cated spatula is then used to adapt the material aroundthe periphery of the septal defect. During impressionmalting attempts are made to record only one nasal cav-ity and only the perimeter of the defect. It is preferablenot to record in the impression both sides of the sep-tum, contrary to the impression technique used to con-struct nasal septal obturators.14,15

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Fig. 3. Impression of nasal septal defect. Two cotton-tippedapplicators saturated with silicone placed in one nasal cavityand injected remainder of silicone impression material fromother nasal cavity through defect.

Fig. 5. Finished intranasal stent, held by lo ng tweezers duringfinal insertion should be trimmed sufficiently to conceal itsmargins completely beyond mucocutaneous junction of ex-ternal nares for be tter esthetics.

Fig. 4. P atency of this highly po lished intranasal stent is dem-onstrated by having cotton-tipped applicator placed throughstent.

T h e i m p r e s s i o n s h o u l d d e m o n s t r a t e p r o p e r e x t e n s i o nin to the vent r ic le of the nasa l ves t ibu le , th e la te ra l wa l lo f t h e n a sa l c a v ity , a n d im p r in t o f t h e d e f e c t p e r ip h e r y .An acceptable impress ion i s f la sked in denta l s tone andp r o c e s se d i n c l e a r p r o c e s se d p o ly m e th y l m e th a c r y l a t e .A f t e r r e c o v e r y , t h e s t e n t is h o l lo w e d w i th b u r s a n d r e n -d e r e d s m o o t h w i t h r u b b e r p o i n t s . T o e l i m in a t e a n y ar-e as o f r e m a in in g r o u g h n e s s i n t h e i n t e r n a l su rf a ce o f t h es t e n t , a t h in l a y e r o f a u to p o ly m e r i z in g a c r y l ic r es in i sp a in t e d a n d a l l o w e d to p o ly m e r i z e f o r 2 0 m in u te s a t2 0 p s i i n a p r e s su r e p o t . I t is p r e f e r r e d t o u se h e a t - p r o -cessed ac ry l ic r e s in for the bulk o f the s t en t an d o nly thehme r sur face i s to be covered wi th a u topo lyme r ized res in .A l l sh a r p e d g e s a n d p r o j e c t i o n s a r e sm o o th e d a n d t h eo u te r su r f a c e o f th e s t e n t i s h ig h ly p o l i sh e d ( F ig. 4 ) .C a r e m u s t b e t a k e n n o t t o r e d u c e t h e r e t e n t i v e e x t e n -s io n p o s t e r io r ly o n to t h e f l o o r o f t h e n a sa l c a v i ty o r a n -t e r i o r ly i n to t h e v e n t r i c l e. T h e a c r yl i c re s in e x t e n s io n sin t e r f e r in g w i th i n se r t i o n a n d w i th d r a w a l o f th e s t e n ta r e m o d i f i e d a t t h e t im e o f i n se r t i o n . T h e s t e n t sh o u ldn o t e x t e n d p as t t h e m u c o c u t a n e o u s j u n c t i o n o f th e e x -t e r n a l n a r e s f o r b e t t e r e s th e t ic s a n d e a se o f m a n ip u l a -t ion (F igs . 5 and 6) .

A 1

Fig. 6. A, Large nasal septa[ defect with irregular margins. B,Nasal septal stent.

I t is advisable to duplica te the f in ished stent a f ter tem-p o r a r y o b tu r a t i n g i ts l u m e n w i th a r t is t ' s c la y. T h e s t e n ti s lubr ica ted wi th p e t ro l eum je l ly and inves ted in a c rownand br idge f la sk. Af te r se t t ing o f the s tone , the f la sk i so p e n e d a n d th e s t e n t c l e a n e d w i th u l t r a so n i c c le a n er . An e w h e a t - p r o c e s se d a c r y l i c r e s in s t e n t c a n t h e n b e c o n -s t r u c t e d . T h e d u p l i c a t e d s t e n t is h o l lo w e d a n d s to r e d i nwa te r in a sea led p las t ic bag fo r fu ture u se in case of losso f t h e o r ig in al s t e n t .

P a t i e n t s sh o u ld b e i n s t r u c t e d o n h o w to i n se r t a n dremov e the s ten t . P rop er or ien ta t ion o f the s ten t i s h ighlye m p h a s i z e d d u r in g t h e i n se r t i o n p h a se . R e m o v a l o f t h es ten t can usua l ly be achieved by d ig i ta l p ressure to thes ide o f t h e n o se ; h o w e v e r , t h e p a t i e n t sh o u ld b e i n -s t r u c t e d o n h o w to r e m o v e a n d in se r t t h e s t e n t w i th t h ea id o f l o n g tw e e z e r s . T h e p a t i e n t i s i n s t r u c t e d o n d a i lyc l e a n in g o f t h e s t e n t w i th m i ld so a p a n d w a te r. F r e q u e n tp o s t i n se r t i o n a p p o in tm e n t s a r e n e c e s sa r y t o a sc e r t a intha t pressure a reas a re e l imina ted , th e t i ssues sur rou nd-

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ing the s tent are not in f lamed, and the pat i ent i s com-fortable.S U M M A R Y

Large nasal septal defects can be indirectly obtur atedby the use o f heat-processed acrylic resin intranasal s tent.Th e m edial wal l o f the s tent wi l l a l low for part it ion ofthe tw o nasal cavities and the pate ncy o f s tent wi l l al lowfor com fortable breathing. Con struction o f conven tionalheat-pro cessed nasal septal obturators is l imited to smalldefec ts that occur in the anter ior s eptum.REFERENCES

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tistry.0022-391 3/97/$5.00 + 0 . 10 /1 /79 328

C l i n i ca l e v a l u a t i o n o f f i v e a d h e s i v e s y s t e m s : T h r e e - y e a rresu l t s .Tyas MJ. I nt D entJ 1996;46:10-4.

Pu rp ose . Thi s ar ti cl e reported on the c l in ica l per formance o f five dent in adhes ive systems innon unde rcut Clas s V abras ion le s ions over a per iod o f 3 years.M a t e r i a l a n d M e t h o d s . O n e h u n d r e d n o n u n d e r c u t C l a ss V a b r a si o n l e s io n s w e r e r es t o r ed in15 patients aged 36 t o 79 years (mea n age 63 years) . Five different systems were used to place 20res torat ions : Al l -Bond (Bi sco Dental Products ) , Photobond (Kuraray) , Denthes ive (Heraeus -Kulzer Gm bH ), Pertac-Bond (Espe Gm bH ) and Ger is tore (Den -M at Corp) . The microf i ll res incom pos i te (S i lux , 3M Den tal Pro ducts ) was used as the f inal restorative mater ia l ex cept for thePh oto bo nd mater ia l, w i th whic h Clearf il P ho to anter ior mater ia l (Kuraray) was used . Al l prod-ucts were used accord ing to the manufacturer 's d irec t ions . Th e res in com pos i te wa s p laced andcured in a s ingle increment and f in i shed and pol i shed immediate ly af ter cur ing. Res torat ionswere exam ined after 3 mo nths , 6 mo nths , and 1 , 2 , and 3 years . They were recorded as present orabsent and the cumulative survival rate was calculated with l i fe table analys is . The results wereana lyzed statistically.Re su l t s . There was no s ign i fi cant d i fference amon g the mater ia ls te s ted wi th respect to pat i entage or tee th res tored . Th e los s rate of res torat ions varied from 26% to 95% am ong the f ivesys tems at the 3-year observat ion per iod . Products that b ond ed t o the dent in v ia a hybr id layer( A l l - Bo n d a n d P h o t o b o n d ) w e r e m o r e r e t e n t i v e t h a n t h o s e d e s i g n e d t o b o n d c h e m i c a l l y(Denthes ive and Pertac-Bond) to dent in . Two products (Ger i s tore and Pertac-Bond) that at -temp ted to ach ieve bon ding betw een the ir carboxyl groups and dent in ca lc ium were hydrophi l i c ,wh ich probably c ontr ibuted to the ir lack of c l in ica l succes s . 32 References. R P R E N N E R

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