550 MATERIALS FOR RESTORING FRONT TEETH

and with doses of 1.0 to 2-0 mg. a fall in ventricularrate is seen within an hour, and a maximum effect

in six to seven hours. After a single dose of 1.0 or1.5 mg., the ventricle returns to its original rate inabout three days. Six hours after the initial dose,further doses of 0-5 or 1.0 mg. may be given dailytill a full therapeutic effect is obtained. A main-tenance dose of 0-5 mg. was found to correspond to2 c.cm. of standard digitalis tincture. These results

suggest that digoxin is rapidly eliminated from thebody. Nausea and vomiting are produced by all

potent preparations of digitalis when given insufficient quantity, probably by a reflex from theheart, and digoxin is neither more nor less liable toproduce these effects than the tincture. Similarlyboth digoxin and the tincture seem equally liableto cause extrasystoles. The other glucoside, digital-inum verum, given intravenously in doses of 2.5 to5.0 mg., produces its preliminary and maximumeffects on the heart-rate in much the same time as

digoxin, and their duration is also comparable. Itis ineffective, however, by mouth, it does not lowerthe heart-rate, and it gives rise to abdominal discom-fort and diarrhoea, the result of a direct action onthe bowel.To sum up, we have in digoxin a pure digitalis

glucoside, requiring no standardisation, which is ofuniform potency, and is capable of producing rapidventricular slowing when given by mouth or intra-venously to patients with auricular fibrillation.

Digitalinum verum, another pure glucoside, has thesame effects when administered intravenously, but isof no value when given by mouth.

TRAFFIC IN DANGEROUS DRUGS

THE convention for the limitation of the manu-

facture and distribution of dangerous drugs of 1931,having received the required number of ratifications,came into force on July 13th. If its object is to beachieved it will require to be universally applied, andits effectuation will depend upon the legislative andadministrative measures adopted by the several

contracting parties. To this end a model adminis-trative code has been issued by the League of Nationsin the hope that governments will have regard to itwhen giving effect to the convention. The completedreturns for the year 1931 have led the advisorycommittee on traffic in opium to think that in thatyear the manufacture of narcotics approximated tothe estimates of world requirements for medicalconsumption which were put forward by the Leagueof Nations. There is, however, ground for believingthat clandestine factories for the manufacture of

morphine and heroin have sprung up in various partsof the world, and that poppy cultivation on a largescale is being carried on in several of the provincesof China. The exports from France in 1932 were

reported to be 155 kg. of morphine, 22 kg. of heroin,and 55 kg. of cocaine. The representative of Germanyinformed the advisory committee that a supplemen-tary law had been promulgated to restrict furtherthe manufacture of narcotic drugs. The Portuguesedelegate assured the committee that a new policywas contemplated in Macao with a view to suppressthe traffic in prepared opium with which that porthas long been associated. The Bangkok agreement,which dealt less drastically with the suppression ofopium smoking than was provided for by the HagueConvention of 1912, has been ratified by Great Britain,France, and the Netherlands. At the request of therepresentative of Italy, the secretariat of the Leaguehas been instructed to make inquiry (1) as to theannual value of the lawful consumption of opium,

coca leaves, and manufactured drugs, and (2) as tothe annual loss of wages among addicts, and the

expenditure incurred by the different States on

preventive measures, treatment, and suppression inconnexion with addiction.

In pursuance of the resolution passed by the

assembly of the League two years ago with a view tolimit cultivation of the the opium poppy and theharvesting of coca leaves, questionnaires are about tobe forwarded to producing States, members of theLeague, and to non-member States. Replies to thequestionnaires, when received, are to furnish thedata for the conference on the limitation of rawmaterials which was desiderated by the assembly.The advisory committee has suggested a meeting ofrepresentatives of Persia, Turkey, and Yugoslavia,as principal producing countries, with one or twoindependent persons, in order to devise an agreementon the limitation of production. Presumably,representatives of China and India will be invitedto assist in such investigation.

MATERIALS FOR RESTORING FRONT TEETH

THERE are three materials which can be used forfilling front teeth-gold, porcelain, and a translucentcement. Gold is the most ancient of these, but itis not necessary to be very old to remember tedioushours spent in the dental chair while gold foil washammered into a tooth piece by piece. The valueof gold for this purpose depends on its property ofwelding in the pure state, the solid plug being verystable and undergoing little change even over manyyears. The drawback is that gold filling in a fronttooth is easily observed, and when gold was the- onlymaterial available people unfortunate enough to havecarious front teeth were compelled to carry aboutvisible signs of the dentist’s attention. To-day gold islittle used for filling front teeth, though in the formof the gold inlay, in which a reproduction of the

cavity is cast and cemented in, it is still much used forback teeth. But while this method avoids hammeringthe prime defect of a filling completely unlike a toothin colour remains. Yet at the annual meeting of theBritish Dental Association held in Leicester therewere still advocates of cohesive gold for front teeth.Prof. W. H. Gilmour, who opened a symposium ontheir restoration, stressed the great value of its

strength and permanence. An increasing number ofthe public however dislike intensely the glitter of

gold in the front of the mouth. The use of a porce-lain inlay cemented into place was advocated byMr. C. S. Morris. This is of considerable strengthand is capable of matching a tooth almost exactly,but it requires an elaborate and expensive electricfurnace, the technique is difficult and takes time,and restorations in porcelain are necessarily expensive.A serious defect is that the cement used to fix theinlay into place in time darkens and spoils theappearance. As an inlay porcelain is little used,though in the limited field of crowns it is the last wordin refinement, for it can be employed withoutdestroying the pulp and gives a restoration quite indis-tinguishable from natural teeth. Ground porcelainfilling, in the manner devised by W. Dall, and advo-cated by Mr. S. F. Webb, is wrong in principle as itnecessitates the removal of sound tissue in order tomake the cavity fit the inlay. Silicate or translucentcement, advocated by Mr. G. N. Groves, is placedin the cavity in a plastic form which rapidly sets.It is not adhesive, a fault it shares with gold andporcelain, and its edge strength is poor compared

1 Brit. Dent. Jour., July 15th.

551SUCCESS IN CATARACT EXTRACTION

with gold. It is translucent and can match thetooth exactly, but in time it tends to discolour.The filling may have an irritant effect on the pulpand if the latter is not protected it may die. Yetthe ease with which it may be inserted, its cheapnessas a material, and the fact that it does not need

expensive apparatus like fused porcelain or take theinordinate time required by cohesive gold all markit out as the material of choice. For practical.purposes translucent cement has replaced all othermethods except for unusual conditions. When the

filling discolours it can be replaced without furthersacrifice of tooth substance, and even the lack ofedge strength can be overcome by the cunning useof a gold or stainless steel wire support much likereinforced concrete.

HYSTERIA IN DOGS

By this time many dog-owners have become

unpleasantly familiar with canine hysteria or "frightdisease." Its principal characteristic is that theanimal, previously healthy, gets fits of apparentterror, followed by more or less depression. These

symptoms have been put down by some to encepha-litis, but Mr. H. D. Walston’s letter in Nature forAugust 12th (p. 243) suggests a different explanation.The evidence he has collected indicates, he says,that the disease is connected with vitamin-A deficiency,associated with ingestion of a substance present indog biscuits and other cereals. Fifty-four dogssuffering from hysteria were studied, and it was foundthat all but one were receiving a diet in which cerealspreponderated. Twenty-six of them were given thesame diet and remained hysterical, whereas 28 werechanged to a diet containing more vitamin A andthereupon recovered. It is recalled that E. Mellanbyproduced symptoms resembling canine hysteria byadding wheat germ to the diet of dogs which weregetting too little vitamin A. It may also be recalledthat as long ago as 1928 the treatment which wasfound most successful was the removal of all biscuitfrom the dietary’! At the same time Mr. Walston’swork does not on the face of it explain why the diseasewas not observed until about ten years ago, and whyit has increased so rapidly in both America andEngland.

TIRED LORRY-DRIVERS

THE relation of fatigue to accident needs no demon-stration. What would be thought of railway com-panies if engine-drivers were encouraged or permittedto work for long periods without sufficient intervalfor sleep ? Yet haulage contractors, it appears,employ lorry-drivers under conditions which makeaccident almost inevitable. Factory and workshoplaw makes great efforts to preserve the welfare andsafety of employees. The overtired factory handmay injure himself ; the overtired lorry-driver maycause the death of others beside himself. Section 19of the Road Traffic Act was intended to regulatethe working hours of drivers ; either the section isnot strong enough or it is not being properly enforced.At a Leicester inquest on August 14th a lorry-driverwas found to have met his death by colliding with atram standard. He had taken loads of potatoesfrom Boston to Rochdale on the Monday night, toLeeds on the Tuesday night, part way to Scarboroughon the Wednesday night (when his lorry broke down),and he was on the way to Coventry when the fatalaccident occurred early on Friday morning. Hiswidow said the deceased had only 1 hours’ sleepin the period from Monday night to Friday morning ;

1 THE LANCET, 1928, i., 249.

he had told her he was dead beat before he startedon the Thursday night, and before he died he said44 I must have dozed off." The haulage contractorwho employed the driver told the coroner that hethought the man would get some rest between hisjourneys after delivering his loads. The coroner

said it was slave-driving ; the jury attributed theblame to the inhumanity of the employer, and thecoroner agreed that the employer was morallyresponsible. At Bolton, a week later, there was asimilar inquest on a lorry-driver who crashed intoa tram standard. The man’s mate gave the itinerary.He and the deceased left Oldham at 3.45 on a Sundayafternoon ; they reached Edinburgh at 7 next

morning, and Glasgow at 11. Leaving Glasgow at1 P.M. on the Monday, they reached Lanark at1.30 P.M., stayed there till 4.15, and then left forCarlisle. Carlisle was reached at 8 P.M. ; they leftan hour later and drove to Oldham. The driverswere paid by the journey, and the deceased wasanxious to arrive at Oldham early in order to snatcha few hours’ sleep before starting the same day forBournemouth with a load. The employers fixed notime-limit for the journeys ; the drivers had an

incentive to make as many trips as possible in orderto earn good wages. Traffic accidents are largelyavoidable. Here is a class of accident which certainlycan and ought to be avoided.

SUCCESS IN CATARACT EXTRACTION

FoR 20 years or more the choice between twomethods has been before the ophthalmic surgeonwho has to remove a cataract. In the intracapsularmethod-minor differences being associated with thenames of Smith, Barraquer, and Sinclair-the lensis removed entire after rupture of the suspensoryligament. In the extracapsular method the capsuleis first incised and subsequently dealt with if neces-sary by needling. The objection to the former isthe possible risk of loss of vitreous, and the majorityof ophthalmic surgeons in this country still pin theirfaith to the extracapsular method as now practised.In a recent article 1 Mr. Maurice H. Whiting showshow in skilled hands it has become one of the mostsuccessful operations in surgery, and enumeratesthe precautions necessary to ensure success. First,as a preliminary to operation, a bacteriologicalexamination of the conjunctival sac should invariablybe made. In the old days at Moorfields the test ofbacteriological cleanliness was to place a pad andbandage over the eye the night before operation ;the pad was removed in the morning, and if anydischarge was found on it, or if the lids were stucktogether, operation was postponed. Now the prac-tice is to swab the conjunctival sac 48 hours previousto operation, and to smear the secretion so obtainedover the surface of a blood agar slope. The detectionafter 48 hours’ incubation of any organisms otherthan the Staphylococcus albus or the xerosis bacillusis a bar to immediate operation. With this pre-caution the risk of suppuration has been eliminated.Previous to its adoption the proportion of suppurationsat Moorfields was between. 1 and 2 per cent. Thesecond point in pre-operative care is appropriatetreatment when cataract is associated with diabetes.

During or after operation the great danger to be

guarded against is the patient’s squeezing out vitreous.Careful management of the speculum is always neces-sary, but in addition to that it is found in manycases advisable to paralyse the orbicularis by injec-tions of novocain, either from a point opposite the

1 Irish Journal of Medical Science, March, 1933.