LETTERS TO THE EDITOR
THE JO U R N A L d e vo te s th is s e c tio n to c o m m e n t b y re ad e rs on to p ic s o f c u rre n t in te re s t to d e n tis try . T h e e d ito r re serve s th e rig h t to e d it all c o m m u n ic a tio n s to f i t a v a ila b le s p a c e and re q u ire s th a t a ll le tte rs b e s ig n e d . P rin te d c o m m u n ic a tio n s d o n o t n e c e s s a rily re fle c t th e o p in io n o r o f fic ia l p o lic y o f th e A s s o c ia tio n . Y o u r p a rtic ip a tio n In th is s e c tio n is In vite d .
N e w ag e-a ssessin g m eth o d
■ I am currently working with some scientists at the U niversity of Calif ornia at San D iego in La Jolla. R ecently, a new m ethod of assess ing the age of living human beings and other long-lived mammals has been developed using the racem ization reaction of aspartic acid con tained in enam el1 and dentin.2 The developm ent o f this technique is an outgrow th of w ork on the use of am ino acid racem ization reaction to date fossil m aterials. T he racem ization technique is based on th e fact that initially all the aspartic acid present in proteins is of the L-configuration. H ow ever, in m etabolically inert proteins (those which are not regenerated during the life span of an animal) a reaction called racem ization slowly converts some of the L -aspartic acid to D -aspartic acid; thus, the D /L aspartic acid ratio steadily increases with increasing age of the animal. N o such increase is ob served in m etabolically active pro teins such as hem oglobin. We have m easured the extent of aspartic acid racem ization in enamel and dentin in teeth extracted from my patients ranging in age from 8 to 75 years old. Only a lim ited num ber of teeth from older individuals (greater than 65 years old) have been analyzed. We would, therefore, like to request
that any teeth ex tracted from indi viduals g reater than 65 years old be sent to us for analysis. T he tooth should be accom panied by the date of extraction and the birthdate of the individual. One of the m ore interesting appli cations of our w ork on racem ization in hum an teeth would be to examine the claim s of unusual longevity among peoples living in E cuador, H unza, and G eorgian Russia. We would greatly appreciate obtaining specim ens from anyone having access to teeth (or even the roots) from people in these regions. A gain, we would require— along with the to o th —the age claimed by the individual and the date the tooth was extracted. Since this aging technique can be applied to any long-lived mammal, we have been interested in analyzing teeth from large anim als of known age. Initial results on teeth from sperm w hales look encouraging, and we plan to analyze the spotted dolphin, also. T he potential application of race m ization ages is in constructing age profiles fo r natural populations of land and sea m am m als. Such infor m ation would be very useful in eco logical studies, wildlife m anagem ent, and conservation. We welcome any specim ens of teeth from dom esti cated or captive m am m als, of known age, and especially teeth from very old anim als. Please send dry specim ens (not to
be returned) to J. F. Jo n e s, D D S , 7761 H erschel A ve, L a Jolla, Calif 92037. T his is an exciting new “ y ard stick " to which 1 feel dentistry can contribute a great deal. W e’ve already proved the La Jolla Indians w ere here 50,000 to 60,000 years ago instead of 10,000. JER R Y F. JO N E S , D D S LA JO L L A , C A L IF
1. H e l f m a n , P . M . , a n d B a d a , J . L . A s p a r t i c a c i d r a c e m i z a t i o n in t o o t h e n a m e l f r o m living h u m a n s . P r o c N a tl A c a d Sci U S A 72:2 891 , 1975. 2. H e l f m a n , P . M . ; B a d a , J . L . ; a n d J o n e s , J . F . A s p a r t i c ac id r a c e m i z a t i o n in d e n t i n e f r o m living m a m m a l s , in p r e p a r a t i o n .
D e n t i s t is ‘t a k e n ’
■ 1 feel that I’ve been taken by a con fidence man and that the j a d a was his unw itting accom plice. O n page 41 of the January 1967 j a d a , a com pany ended its advertisem ent with this statem ent: “ A generation from now y o u r(trad e name) will be a m useum piece . . . but if anyone asks, you can say ‘Sure it still runs . . . it’s m ade by com pany ( )■’ ” Based on this and sim ilar claim s for longevity which this com pany had been making in previous issues of t h e j o u r n a l , I p urchased a new unit X in 1966. This w eek my servicem an inform ed me that repair parts are un available and the only thing he can JADA, Vol. 92, M arch 1976 ■ 4 9 7
provide would be parts from a used unit if he can find one to strip. T his sam e situation arose last year and I obtained the help of the A D A ’s Council on D ental M aterials and D e vices. It w rote the com pany and an apparently used part was provided. I find this totally unacceptable. I do not believe that a major investm ent such as a dental unit should have to be serviced with used parts years be fore the unit is fully depreciated. H ow can the com pany make such glowing prom ises and then be p er m itted such sloppy practices? H ow can it expect equipm ent to function into the next generation, when repair parts are unavailable now ? P erhaps, it m eant a generation of fruit flies. If so, you should require it to be m ore specific in its advertisem ents. A pparently, the Council on D ental M aterials and D evices has a very lim ited effect on the com pany. I would like to m ake a suggestion that until its pow ers increase, you could make a contribution by requiring a statem ent fo r each advertiser, such as: “ T he m anufacturer w arrants the availability of new repair parts for a period of X y ea rs.” T he reader then could make an inform ed decision based on facts, not flim-flam. I believe I have a right to expect b etter things from advertisers who are perm itted to solicit my patronage in my professional journal. JA M E S T . O ’ C O N N O R , D D S G O S H E N , NY
state board was a reiteration of the law stating that a hygienist could only w ork w ith supervision of a dentist. I agree with the author that sys tem atic preventive dentistry is imper ative for residents of county and nurs ing hom es and feel that the state board should m ake exceptions for hygienists as long as they are checked by a li censed dentist. R A L PH A . B E R M A N , D D S SO U T H B E N D , IN D
G rateful fo r assistance • I wish to express my gratitude, and my colleagues join me in this ex pression, for the excellent assistance provided us and the courtesies show n us during the preparation for publica tion of our article, “ T he influence of proxim al retention grooves on the re tention and resistance of Class II preparations fo r am algam s” (N ovem ber j a d a ) . D ue to the necessity for meeting a personal deadline and because I could not conveniently locate an article by Miles I. M arkley relating to the sub je c t m atter covered in our article, I com m itted a serious error in not re ferring to D r. M arkley’s publication. D r. M arkley has m ade excellent contributions to our profession, both as a practitioner and publisher, and influenced me considerably in deter mining my present philosophy and concept. I am very eager to acknow ledge D r. M arkley’s influence. W . D . CRO CK ETT, DDS V IR G IN IA C O M M O N W E A L T H
On dental supervision
U N IV E R S IT Y
■ I recently read an interesting article on dentistry and county home resi dents. O ver a year ago, I w rote to the In diana S tate Board of D ental Exam iners requesting perm ission for my dental hygienist to spend one day a m onth at nursing hom es where 1 am the dentist on call. T he invalid pa tients are badly in need of prophylaxis and, with my portable equipm ent, a very thorough prophylaxis could be perform ed. I would stop in the even ing and exam ine the patients to check on her w ork. T he answ er I received from the
R IC H M O N D , VA
A ‘m agnificent jo b ’ ■ M ay I express my adm iration and appreciation for the magnificent job you have done as editor. Y our editorial courage in publishing both sides of controversial subjects has m arked a new high for our j a d a and the A m erican D ental A ssocia tion. H ere’s wishing you another great editing year.
498 ■ LETTERS TO THE EDITOR / JADA, Vol. 92, March 1976
AV ER Y S. K R A S H E N , D D S C H IC A G O
H urts dental image m I ca n ’t help adm iring R enate Joseph for writing her letter of indignation (D ec 1 A D A N e w s) regarding lec tu re rs’ crude put-dow ns of th e fem ale sex. I have known people in the audi ence to w alk out during offensive presentations. (People in my audience w alk out for other reasons.) O bscenities hardly belong on the agenda o f the dental lectu rer’s circuit. T his also should include racist jokes. T he image o f dentistry is suffering enough from oth er indiscretions with out being derogatory about the human race. W IL M E R B. E A M E S , D D S EM O R Y U N IV E R S IT Y
‘P icking’ a patient m As an am using com m ent, may I call your attention to the copperplate en graving by L ucas van L eyden on page 953 of the N ovem ber j a d a ? If you observe the young lady assis tant with the innocent posture, you will notice that she is picking the purse o f the poor victim. B E R N A R D S. K R IST A L , D D S RO CH ESTER, NY
R eference service fo r serum s ■ T he following is inform ation on a reference service for serum s contain ing selected tissue antibodies. I sub mit this on behalf of the International Service for Im m unoderm atology L aboratories (IS IL ) for publication in your journal. R eference serum s for antinuclear antibodies, sm ooth m uscle, m ito chondrial antibodies, tw o types of thyroid antibodies, and other tissue antibodies are available for labora tory directors and responsible labor atory w orkers through the IS IL , a nonprofit foundation. O ne of the objectives of the IS IL is to assist responsible laboratory w ork ers achieve more reproducible and reliable clinical laboratory tests in th e diagnosis o f autoim m une diseas es.