Cornerstones, Milestones, Steppingstones and Stones … · The earliest refrences to saliva medical con ditions probably originate in the ancient Me sopotamia, in the 7th century

13

• Chapter 1. Cornerstones, milestones, stepping�stones and stones in the history of salivary glands •

C H A P T E R 1Cornerstones, Milestones, Stepping�stonesand Stones in the History of Salivary Glands

Abraham M. Baruchin

CHAPTER OUTLINE

The early period (Fifth century B.C. — earlyearly seventeenth century A.D.) ................ 14

The Salivary Period .................................. 15

The salivary Glands .................................. 16

Surgery ................................................... 18

Sialography ............................................. 19

References .............................................. 20

Sialoendoscopy is looked upon as one of themodern discoveries. However, in this reviewwe will trace the idea’ of removing sialoliths’back to its roots and review its progress un�til it attained its modern shape.

By the time our forebears, in the NearEast, reached the level at which they were re�cording their surgical concepts, their sophisti�cation leaves us abashed as well as amused. Thefirst written record containing medical infor�mation date about 2500 B.C. Clay tablets fromthis time have been discovered in Mesopo�tamia.

The earliest refrences to saliva medical con�ditions probably originate in the ancient Me�

sopotamia, in the 7th century BC., the Assyri�an king Asurbanipal assembled a library ofmanuscripts of vast scale(aka the Assyrian Her�barium which, gives a list of some 700 medici�nal and semi�medicinal plants arranged accord�ing to use and application), including Sumerianand Akkadian medical stone tables dating to2000 B.C. Specifically, according to Thomp�son1, belladonna was mentioned as useful rem�edy “to stop the flow of saliva”.

Medicine in ancient Egypt was but one as�pect of an advanced civilization. It was notpracticed by witch doctors as in primitivetribes, with mixture of magic, herbal remedy,and superstitious beliefs. This was acknowl�edged by Homer in the Odyssey: “In Egypt, themen are more skilled in Medicine than any ofhuman kind”.

Several medical papyri have survived theages. They contain prescriptions for treatingdiseases of the lungs, liver, stomach, bladderand for various afflictions of the head and scalp.The Egyptians conception of the human body,then, was as a network of interconnecting chan�nels and analogous to the branches of the Nileand the artificial canals of their own country.Notions of physiology and disease were all an�

14

• Modern Management Preserving the Salivary Glands •

chored in the concept of the heart as the cen�ter of the organism. The heart was one’s part�ner: it spoke to a person in his or her solitude.It was at the same time the engine of all thebodily functions, not only of one cardinal func�tion, the circulation, as modern science re�vealed. From the heart proceeded channels(metu) linking all parts of the body together.These channels, the Egyptians believed, con�veyed not only the blood, but also air (reach�ing the heart from the nose, they thought),tears, saliva, mucus, sperm, urine, nutrimentand feces, as well as harmful substances con�ceived to be the agents of pain and illness. Notonly blood vessels were considered as metu, butalso the respiratory tract, tear duct, ducts ofvarious glands, spermatic duct, the muscles,tendons and ligaments. According to the Ber�lin Papyrus which was aquired by GiuseppePassalacqua in Seqqara and was sold on toFriedrich Wilhelm IV of Prussia with otherobjects in 1827 for the Berlin Museum. Thestyle indicates that it is 19th Dynasty andWreszinski2 translated it into German in 1909.An ancient report reads as follows: “The patientsuffers a great epigastric pain. He feels a heavy,hot and inflamed body. He complains of beingunable to tolerate his clothes and feels they donot warm him. He feels thirsty during thenight. His saliva has the taste of unripe fruits.His muscles pain him as if he walked for a longdistance.”

Votive tablets found during the excavationof shrines of the Graeco�Roman god of medi�cine (Asklepios or Aesculapius) associate thehealing of superficial lesions with contact withthe oral cavity of non�poisonous serpents. It issuggest by Angeletti and Agrimi, 3 that thismay have been the empirical exploitation of thehealing properties of salivary growth factors.By immunohistochemistry and immunoblot�ting it was demonstrate the expression of theepidermal growth factor and its receptor in theoral, upper digestive, and salivary epithelia ofElaphe quatuorlineata, a species probably usedin healing rituals.

Micheli�Pellegrini4 divide the historical de�velopment of anatomical knowledge of the sal�ivary glands into two periods:

A. the early period• From the fitfth century B.C., to the

seventeenth century A.D.B. the salivary period

• From the seventeenth century to ourdays.

The early period(Fifth century B.C. — early early

seventeenth century A.D.)

Many foundations of modern Western med�icine lie in Classical Greece from about 800B.C.E. to about 200 A.D. During this period,Greek medicine departed from the divine andmystical and moved toward observation andlogical reasoning. These ideas spread through�out the Mediterranean world and as Far Eastas India, and their influence has remainedstrong in the West to this day.

Hippocrates: (470 B.C. — 410 B.C.)The accepted explanation in his writes that

saliva was a “humor “which circulate in thebody as did bile, gastric juice and urine persist�ed unchanged into the Renaissance. It was onlyby repeated investigations aided by later micro�scope studies that the true origin and functionof the salivary glands was finally reveals.Hippocrates described mumps as an illness ac�companied by swelling of the ear and painfulenlargement of the testes, either unilaterally orbilaterally. Swellings appeared about the ears….In all cases they disappeared without givingtrouble, neither did any of them come to sup�puration, as is common in swellings from othercauses. They were of a lax, large, diffused char�acter, without inflammation or pain… In someinstances earlier, and in others later, inflamma�tions with pain seized sometimes one of the tes�ticles, and sometimes both. Hippocrates alsodescribed ranulas and thought that they weresecondary to inflammation fascinating clinicalentity, this syndrome has received scant atten�

15


tion in the medical literature and has been de�scribed only in anecdotal reports.5

Aulus (Aurelius) Cornelius Celsus (25B.C. — 50 A.D.) in book 6 Chapter 16 of hiswork: De re medicina described the parotis andin book 7 the clinical appearance of the ranula.6

Galen of Pergamum Galen (129 A.D. — 200A.D.). According to Galen’s theory the bloodwas filtered in the brain, so that its impuritiescould be discharged through the cribriformplate (a lamina of the ethmoidal bone so�calledbecause it is akin to a sieve — cribrum in Lat�in) giving rise to tears, saliva, and mucus andsweat. He published many books, which he hadto rewrite after his library was destroyed by firein 191. This book became extremely influentialin the Middle Ages, when they were well�readin both the Byzantine empire and the Arabworld. Great scientists like Ibn Sina, Ibn Rushdand Vesalius based their researches on thefoundations laid by Galen.

Oribasius (325—400 A.D.) was an ency�lopжdist and healer from Pergamon (like Ga�len). He was a friend, physician and adviser toEmperor Julian ‘the Apostate’ (332—363 A.D.).Julian, in any case, encouraged Oribasius tocompile his Medical Encyclopжdia of 70 or sobooks, about a third of which survives, and inwhich he carefully and meticulously quotes ear�lier authors thus allowing us to glimpse thesurprising richness and knowledge of ancientmedicine He refers to calcareous concentra�tions in the mouth and to the ways for theirremoval.

Alexander, a Roman physician of the in theSecond Century described “A person who spata stone out his mouth”.

Gentile di Fogliano (1412) and AlessandroBenedetti (1490) reported similar cases of prob�able sialolithiasis in the submandibular glands.

Alessandro Achillini (1463—1512) was a cel�ebrated lecturer in Medicine and Philosophy atBologna and Padua. He was the author of Car�ports Humani Anatomia and Anatomicae An�notationes, in which he was the first to describethe malleus and incus and demonstrated that

there are seven tarsal bones. He rediscoveredthe fornix and the infundibulum. He also de�scribed, exactly, the ducts of the submaxillarysalivary glands — a discovery generally attrib�uted to the Englishman Thomas Wharton(1614—1673). (Fig. 1�1)7

Fig. 1�1

Lorenz Heister (Heisterus) (1683—1758) AGerman surgeon attributed the first reports ofsubmandibular sialolithiasis to Fabricius diAcquapendente, Domenico Marchetti, andNicholas Tulpius immortalized by Rembrandt’spainting: Anatomy Lesson of Dr. Tulip.8

Felix Platter (1536—1614) was the first toreport parotid calculi he removed from a Bour�gogne nobleman in 1560.

The Salivary Period

Only after the discoveries between 1634 and1666, does the real history of sialolithiasis shiftsfrom anecdotal case reports to more preciseanatomic and scientific description.

16


Marcello Malpighi (1628—1694) Malpighiwas a pioneer in the use of the microscope,which, as a compound of two lenses, had beeninvented around 1600 by Zacharias Jansen andimproved upon by Galileo Galilei. Further im�provements were made by Anton von Leuwen�hoek (1632—1727) of Delft and Jan Swammer�dam (1637—1680) of Amsterdam, In Malpighi’sseries of treatises published in 1665—6, [Deviscerum structura], one find s the first defini�tive summary of all the knowledge of the sali�vary glands from ancient time to the seven�teenth century.9

Antonio Maria Valsal�va (1666—1723) (Fig. 1�2) In his impressive DeAure Humana Tracta�tushe showed clearly theparotid gland and Stens�en’s duct (Fig. 1�3).

Bartolomeo Eustachi(Eustachius) (1500—1574). In his AnatomicalEngravings which, though

completed in 1552, nine years after the impres�sion of the work of Vesalius, the author was un�able to publish. First communicated to theworld in 1714 by G. M. Lancisi. Aterwards in1744 by Cajetan Petrioli, again in 1744 by B. S.Albinus, and subsequently at Bonn in 1790, theengravings show that Eustachius had dissect�ed with the greatest care and diligence, andtaken the utmost pains to give just views of theshape, size and relative position of the organsof the human body. The facts illustrated bythese figures are so important that it has beensaid that if the author had been fortunateenough to publish them, anatomy would haveattained the perfection of the 18th century twocenturies earlier at least. Their seclusion forthat period in the papal library has given celeb�rity to many names which would have beenknown only in the verification of the discover�ies of Eustachius.10

The salivary Glands

The term “Salivary Glands” was coinedprobably by Andreas Vesalius or Andreas Ve�sal (1514—1564). However, Jean Riolan,(1580—1657) was the first to identify the glan�dular mass of the Protid (1648). Julius Casse�rius 1561—1616)) described in his book Pen�taesthesion (1609) the opening of the parotidin to the oral cavity.

Ambroise Pare believed the parotid to be anemunctory or excretory organ of the brain whileThomas Bartholin(1616—1680) (Fig. 1�4) whois known also for his work on the sublibngualgland described in his Anatomia Reformata,thought the parotid duct was a ligament of apreauriciular gland. Seguignal in 1690 is cred�ited for the first description of of a parotidgland enlarged by asialolith obstructing theStensen’s duct.

Niels Stensen — Nicolaus Steno (1638—1686) (Fig. 1�5), on 7 April 1660, Stensen aged22 years, dissected the head of a sheep, makinghis first discovery by finding the excretory ductof the salivary gland. At once modest and full

Fig. 1�2

Fig. 1�3

17


finding a duct which — as far as I know — hasnot previously been described. It was my inten�tion after removing the ordinary outer parts todo a section of the brain when I happened todecide first to examine the vessels runningthrough the mouth. Examining with that inten�tion the course of the veins and arteries, by in�serting a probe I observed that the point is nolonger enclosed in the narrow sheath but movesfreely in a spacious cavity; and pushing the in�strument further forward, I at once heard itclink against the teeth themselves”.

Elsewhere in his letter to Bartholin, Stens�en modestly calls his discovery an inventiuncu�la — a small observation. In a way, it was thisinventiuncula that would make him most fa�mous, because, the duct of the parotid glandwas named, by one of his Dutch friends, theDuctus stenonianus.

Stensen had of course summoned his profes�sor — and landlord/host — Gerard Blasé (Bla�sius) (1626—1682), to show him his discovery.It was at once dismissed as a badly performeddissection. But on further reflection, Blaséclaimed the duct as his own discovery and in abrief publication entitled General Medicine inthe spring of 1661 laid public claim to it. Theprolonged dispute about the discovery had onlyone result, which was to lead the young Dane

on to a succession of further discoveries.Actually, Stensen stayed for only a fewmonths in Amsterdam, probably accord�ing to plan, but like his Dutch friends hewould continually return to this center ofculture. He made a number of new friendsduring his short stay. The one he mayhave liked best was his contemporary fel�low student Jan Swammerdam, one of thetruly great zoologists, and one of the firstto use a microscope in scientific studies.Among the professors he particularly at�tached himself to was Franзois, De LeBoл or Franciscus Sylvius (1614—1672),who had not only distinguished himselfwith his contributions to the knowledgeof glands and the brain but was also an

Fig. 1�4

Fig. 1�5

of a beginner’s joy in research, he tells of it in aletter to Thomas Bartholin: “Having been al�lowed to dissect on my own, I succeeded in thefirst sheep’s head which I purchased and dis�sected by myself in the study hall on 7 April in

18


admired and inspiring academic teacher. Sylviusand his followers studied the digestive juices,with which they recognized saliva, and vieweddigestion as a kind of fermenting process. Hemay also have organized the first university.

Stensen appeared before the public as anindependent research worker with his disserta�tion: “On the glands of the mouth and recent�ly discovered ducts”, of 6—9 July 1661, withvan Horne presiding. He described factuallyand fully in this paper his old discovery ofSteensen’s duct, but went much further in an�nouncing a number of other gland discoveriesand discussing the problem of the general im�portance of glands. Quietly, he now began toassemble these and other findings on glands ina publication, Anatomical Observations, whichappeared early in 1662. Gerard Blasé made afew last desperate efforts to assert his claim, andwas briefly refuted by Stensen in his Precursorto an Apology of 1663, in which he demonstrat�ed the difference between his duct and the onedescribed by Blasé .11, 12

In 1704 Georgio Baglivi (1668—1707) con�fused parotitis with otitis, however his was thefirst description of referred pain to adjacentstructure such as ear and head. Philippe FrédéricBlandin (1798—1849) and Anton Nuhn (1814—1889) in 1826 and 1845 discovered the anteri�or lingual glands.

Surgery

From 1650—1750, in view of the improvedknowledge of anatomy of the salivary glands,refined surgical techniques were developed.However these were limited to the treatmentof ranulas andsialolithiasis

Lorenz Heister (Heisterus) in 1765 gave thefirst account of primitive parotidectomy. Theconcept of surgical excision of a parotid tumorhas been attributed to Ambroise Bertrandi in1802 (however, he performed only partial ex�cision of the parotid gland as were most of theparotidectomies between 1600—1800). The ini�tial applications of this surgery included a rath�

er extensive approach, causing serious disfigu�ration and disability. Deguise in 1811 suggest�ed double puncture of salivary fistulae, Mores�tin in 1818 tried ligation of the proximal stumpof Stensen’s duct in order to atrophize thegland and stop draiming fistula. In 1830 Lange�beck suggested meticulous dissection of theduct with reanastomosis. Jean Zule’ma Amussat(1796—1856) is credited for total submanduib�ular gland resection. Velpeau (1795—1867)(Fig. 38) in his book: “Nouveaux elements deparotids operatoire” mentioned several sur�geons who performed parotidectomy Carl Al�fred Caspar von Siebold (1736—1807) per�formed In 1781 a total parotidectomy withsome attempt to preserve the facial nerve.While Beclard, Gensoul, and Lisfranc followedby facial paralysis. Johann Ferdinand Heyfelder(1798—1869) who administered the first etheranesthetic in Germany at the Erlangen Univer�sity Hospital on January 24, 1847. He was able,in 1825, to avoid facial paralysis in a parotidec�tomy. Velpeau himself devised a technique forlocating the trunk of the facial nerve. Sedillotand Berard in 1847 performed total parotidec�tomy without carotid ligation but still severedthe facial nerve. By approximately 1850, thefocus shifted toward dissection and the inti�mate relationship of the facial nerve and theparotid gland John Eric Erichsen (1818—1896)In 1869 underscored the importance of avoid�ing the wounding of the hard portion of the 7th

nerve “one can avoid it by dissecting parallel tothe tumor. According to Brunetti et al. the firsttotal parotudectomy with preservation of facialnerve was carries by Codreanu in 1892. GeorgeMcClellan, (1796—1847) shares with ValentineMott, of New York, and Jonn C. Warren, of Bos�ton, the credit of establishing many proceduresnew in this country. He did more than any oth�er surgeon by the number and success of hisoperations to establish completely, as safe andfeasible, the removal of the parotid gland. JohnC. Warren (1778—1856) was the first to useether inhalation anesthesia during his resectionof a parotid tumor in Boston in 184613.

19


Dr. Phillip Syng Physick (1768—1837) Knownas the “Father of American Surgery”, Dr. Phil�lip Syng Physick was on the medical staff ofPennsylvania Hospital from 1794 until 1816Two of his more famous operations occurred onJames Hayes in 1805 and 1806 during which heremoved two large parotid gland tumors fromHayes’ cheek (the larger, seven�pound tumorwas preserved, and is still part of the HistoricCollections14. Grafting of the facial nerve afterresection was attempted in the early 1950s.Other technological advances permitted sur�geons to perform increasingly complex and dif�ficult operations.

Sialography

The discovery in 1895 of X�rays made itpossible to visualize the human skeleton andany deformations thereof but it remained im�possible to detect the organs and the vascularsystem using these rays. É tienne�Jules Marey(1830—1904) was chronophotographer &physiologist His researches were followed upby Bull and Nogues at the Institut Marey,where they made microscopic, X�ray and high�speed analysis films. Following the discovery ofx�rays in 1895 he suggested the use of radio�paque metals to outline glandular ducts andvessels.15 The first sialographic procedure iscredited to Dr Arcelin a French doctor whoinjected in 1912 a submandibular duct with abismuth solution and obtained overhead radio�graphs. The use of bismuth salts was discontin�ued because of cases of bismuth poisoning.Mercury was used in 1904 for the first sialo�gram reported (Charpy and Poirer, 1904)16.Both water�soluble and oil�soluble contrastmedia have been used, with water�soluble me�dia currently preferred. . The use of bismuthsalts was discontinued because of cases of bis�muth poisoning. In 1901 Marcel Guerbet andLaurent Lafay developed Lipiodol® a stable io�dinated oil (first used for syphilis), the opaci�fying properties of which were discovered bychance in 1918 to produce the very first organ�

ic, iodinated contrast agent.17 Dr Jean AthanseSicard (1872—1929) will be remembered as theone who introduced it. Barraud is said to havediscovered the advantage of this substance by in�jecting Lipiodol, instead of water in order to dilatethe Stensen’s duct in a case of sialolithiasis.

Hermann Küttner (1870—1932) (Fig. 1�6),who was professor in Marburg and Breslau, and

Fig. 1�6. Hermann Küttner

who as representative of the Red Cross tookpart in the Greek�Turkish, Boer and BoxerWars, has himself made some important contri�butions to the subject (he successfully graftedbones from ape to man). Most prominentamong his collaborators were Borchard, Stieda,Schüller, and Tietze, who all made names forthemselves in their particular fields. Kuttner in1901, described parotid calculi as rarity and wasalso the first to mention the diagnostic value ofroentgen rays in detecting salivary calculi.18

Examination with sialography was popular�ized in different countries in 1925 and 1926 byT. Barsony, Wiskowsky and D.B. Carlsten andUslenghi respectively.19—22

During the next seven or so decades, tech�nical refinements were made, including fluoros�copy with spot images, subtraction radiogra�phy, and tomography and the whole field ofendoscopy.

20


1. Thompson RC. Assyrain medical texts. Proc.Royal Soc. Med. 17: 1, 1923—4, 19: 29.1925—1926. The Assyrian herbal. London:Luzac and Co. 1924.

2. Wreszinski W. Der grosse medizinische Papy�rus des Berliner Museums (Pap. Berl. 3038).Leipzig: J.C. Hinrichs, 1909. (Medical Textsand Papyri; Papyrus Berlin).

3. Angeletti LR, Agrimi U, Curia C, French D,Mariani�Costantini R. Healing rituals andsacred serpents. Lancet. 1992, Jul 25;340(8813): 223—5.

4. Micheli�Pellegrini and Polayes IM. Histori�cal background Chap1 un Ranikow RM andPolayes IM (eds.) Diseases of the SalivaryGlands WB Saunders Co. Philadelphia 1976

5. Tsoukanelis AS. Hippocrates and the mouth.J Hist Dent. 1998 Mar; 46(1): 25—30.

6. Gonzalez Iglesias J. Stomatology in the workof Celsus. Rev Actual Estomatol Esp. 1987Jul�Aug; 47(366): 47—8, 51—3.

7. Matsen H. Alessandro Achillini (1463—1512) and Ockhamism at Bologna (1490—1500). J Hist Philos 1975; 13: 437—51.

8. Faller A. What place does Stensen’s anatom�ic research have in Lorenz Heister’s surgeryand anatomy? Gesnerus. 1983; 40(1—2):55—66.

9. Campieri C, Persici E, Stefoni S. MarcelloMalpighi and his academic opponents in Bo�logna. Nephrol. 2004 Jul�Aug; 17(4): 625—8.

10. Shampo MA, Kyle RA. Bartolomeo Eustachi.JAMA. 1981 Dec 4; 246(22): 2596.

11. Holomanova A, Ivanova A, Brucknerova N.Stensen�prestigious scholar of the 17th cen�tury. Bratisl Lek Listy. 2002; 103(2): 90—3.

12. Riva A, Testa Riva F. Niels Stensen (Nicco�lo Stenone) and his first scientific offspring:

the salivary glands. Eur J Morphol. 1996 Aug;34(3): 137—41.

13. Moore FD, Collins J. Warren and his act ofconscience: a brief narrative of the trial andtriumph of a great surgeon. Ann Surg 1999Feb; 229(2): 187—96.

14. Toledo�Pereyra LH. Philip Syng Physick:father of American surgery. J Invest Surg.2003 May�Jun; 16(3): 123—4.

15. Debru C. Etienne�Jules Marey: medical in�novation. Bull Acad Natl Med. 2004; 188(8):1413—9; discussion 1420—1.

16. Poirier P, Charpy A. D’anatomie humane.Paris, Masson et Cie, 1904; Vol 4.

17. Bonnemain B, Guerbet M. The history ofLipiodol (1901—1994) or How a medicationmay evolve with the times. Rev Hist Pharm(Paris) 1995; 42(305): 159—70.

18. Rutkow IM, Hempel K. An experiment insurgical education — the first international.exchange of residents. The letters of Halst�ed, Kuttner, Heuer, and Landois. Arch Surg.1988 Jan; 123(1): 115—21.

19. Forrestier J, Sicard J. Methode generaled’exploration radiologi[que] par l’huile io�dide (Lipiodol). Bull Mem Soc Med HospParis 1922; 463—469.

20. Barsony T. Idiopathische Stensen’s gang di�latation. Klin Wochenschr 1925; 4: 2500—2501.

21. Carlsten DB. Lipiodol injection in den aus�fuhrungsgang der speicheldruse. Acta Radi�ol 1926; 6: 221—223.

22. Rabinov K, Weber AL. Radiology of the sal�ivary glands Boston, Mass: Hall MedicalPublishers, 1985.

References

21

• Chapter 2. The Anatomy Of The Submandibular And The Parotid Glands •

CHAPTER OUTLINE

THE CLINICAL ANATOMYOF THE PAROTID REGION ............................ 21

1. Regional Formation/ Classification ........ 21

2. The Parotid Region ............................... 21

3. Conduction PathwaysOf The Parotid Region .......................... 23

THE CLINICAL ANATOMYOF THE SUBMANDIBULAR TRIANGLE ........... 26

References ................................................... 28

THE CLINICAL ANATOMYOF THE PAROTID REGION

The parotid gland has an exceptional posi�tion under the major salivary glands. It is notonly penetrated by major blood vessels andnerves of the head, it is also divided by a strongcapsule, which somewhat limits an enlargementin case of inflammatory or space�occupyingprocesses1—5.

1. Regional Formation/ClassificationThe parotid gland lies topographically in the

parotideomasseteric region, which is definedsuperiorly by the zygomatic arch, posteriorly

by the mastoid process, the tragus and the ex�ternal auditory canal, inferiorly by the marginof the mandible and anteriorly by the frontmargin of the masseter muscle. A lamella ofconnective tissue divides the parotid gland intotwo distinctive layers, superficial and deep,through which the facial nerve branches run.Medially the parotideomasseteric region merg�es with the retromandibular fossa (Regio facieiparot.), which contains soft connective tissue,and passes medially into the peripharyngealspace and dorsally into the infratemporal fossa.The parotid gland extends into the retromandib�ular fossa up to the fan of muscles arising fromthe styloid process, and halts before reaching thepharynx wall (Fig. 2�1).

The ventral extension of the parotideomas�seteric region merges gradually with the buc�cal region. The later extends from the anteriormargin of the masseter muscle to the fascialmuscles and is mostly filled with the corpusadiposum buccae (buccal pad of fat), theBichat’s fat plug.

2. The Parotid Region

The parotid gland is roughly triangular inshape. The superior margin generally lies a fin�ger width (1.5—2 cm) beneath the inferior mar�

C H A P T E R 2The Regional Anatomy Of The SubmandibularAnd The Parotid Glands

Johannes W. RohenJohannes Zenk

22


gin of the zygomatic arch. The gland bordersdorsally on the mastoid process, the tragus ofthe outer ear and the sternocleidomastoid mus�cle whose superficial fascia merges with thebody the gland. The parotid gland forms infe�riorly a triangular lobe (Lobus colli), whichextends beyond the margin of the mandibledown to the platysma.

Within the gland a superior and inferiorduct converge to produce the tough excretoryduct (parotid duct) which leaves the gland, andfollows a course over the masseter muscle to�wards the buccal cavity, often accompanied bygland tissue. This excess tissue frequently formsa lobe of gland (accessory parotid gland), whichvaries in size and may accompany the excreto�ry duct to its orifice. The parotid duct reflectsat the anterior margin of the masseter muscleat an angle of 90° inwards and then proceeds

reflecting anteriorly at the groove of the cor�pus adiposum buccae until it reaches the oralvestibule at the height of the second uppermolar. There it penetrates the buccinator mus�cle and builds a small papilla at the mucosa(buccal salivary papilla). Frequently manysmall glands can be found at the orifice (buc�cal glands), which belong functionally to themucosa. Typically the course of the parotidduct is horizontal, running approximately 2 cmbelow the zygomatic arch and parallel to a pro�jection�line, from the onset of the earlobe to thecarmine of the upper lip.

The parotid duct is about 5—6 cm long andthe diameter varies between 0.5 and 2.3 mm. Inthe vicinity of the gland and the orifice the di�ameter averages 1.4 mm, narrowing to approx�imately 1.2 mm as the duct penetrates the buc�cinator muscle. The narrowest point is the

Fig. 2�1. Parotideomasseteric region and buccal region (lateral view).(J.W. Rohen, Ch. Yokochi, E. Lütjen�Drecoll: Color Atlas of Anatomy. A Photographic Study of the Human

Body, 6th Edition. Schattauer�Verlag, Stuttgart, 2006)

7

65

4

3

2

1

18

17

16

15141312

11

109

8

10

9

8

76

54

3

2

1

1 — N. auriculotemporalis and A. temporalis superf.; 2 — Rr.temporofaciales n. VII; 3 — Tragus; 4 — A. transversa faciei;5 — Gl. parotidea; 6 — Ductus parotideus; 7 — M. masseter;8 — N. auricularis magnus; 9 — R. colli n. VII; 10 — Erb�point,where the cutaneous branches of cervical plexus appear to sup�ply the skin of the neck and the scalp

1 — N. auriculotemporalis and V. temporalis superf.; 2 — A. tem�poralis superf.; 3 — N. facialis (N. VII); 4 — Pars temporofacia�lis n. VII; 5 — A. carotis ext. and V. retromandibularis; 6 — Parscervicofacialis n. VII; 7 — Glandula parotidea; 8 — M. orbicu�laris oculi; 9 — A. zygomaticoorbitalis; 10 — Arcus zygomaticus;11 — Mm. zygomatici; 12 — A. transversa faciei; 13 — Ductusparotideus; 14 — Rr. zygomatici and Rr. buccales n. VII; 15 —M. masseter; 16 — A. and V. facialis; 17 — R. marginalis man�dibulae n. VII; 18 — R. colli n. VII

23

• Chapter 2. The Anatomy Of The Submandibular And The Parotid Glands •

Fig. 2�2. The horizontal section through the parotidfossa. The parotid gland does not enter the peripharyn�geal space (with its deep part) and does not reach themuscles that arise from the styloid process (stylopha�ryngeal, stylohyoidal, styloglossal muscle) (J.W. Rohen,Topographische Anatomie, 10. Aufl., Schattauer Ver�lag, 2000)

orifice itself. The diameter at this point is usu�ally 0.5 mm or less (J. Zenk et al., 1998).

The parotideomasseteric fascia is very denseand consists of various types of connective tis�sue, mainly collagen�fibers. It adheres stronglyto the capsule of the gland, protracting into thegland tissue as lamella and forming lobes whichmake it impossible to dissect the gland from itscapsule. The capsule of the gland also adheresto the fascia of the neighboring muscles partic�ularly the masseter and the sternocleidomas�toid muscle.

An exception is the cervical lobe (Lobuscolli) which has no connections to the fascia ofthe nearby muscles (stylohyoid muscle, poste�rior belly of the digastric muscle and platysma).At the retromandibular fossa, the gland is lim�ited by soft lamellae of connective tissue fromthe peri�pharyngeal space, the fasciae of thestylohyoidal, stylopharyngeal and styloglossalmuscles, and strands of vessels and nerves run�ning through this region (external carotid ar�tery, internal jugular vein, cranial nerves, lym�phatic vessels) (Fig. 2�2).

3. Conduction PathwaysOf The Parotid Region

3.1. Nerves

The sensory perception of the skin coveringthe parotid fossa originates from the great au�ricular nerve which rises perpendicular, fromthe source at the cervical plexus, to the anteri�or of the auditory canal where it then fans outover the parotid gland.

The auriculotemporal nerve arises from themandibular division of the trigeminal nerve, en�ters the parotid fossa behind the neck of themandible and leaves it at the superior marginof the parotid gland; it then follows a verticalpath together with the superficial temporal ar�tery and vein towards the parietal skin.

The most important nerve of the region isthe facial nerve (N. VII), which enters the pa�rotid fossa where it leaves the stylomastoidalforamen and moves ventrically in a line whichcan be drawn from the external auditory canalto the mandibular angle. The nerve then di�

vides into a trunk that runs inferiorly (cervi�cal�facial part) and a trunk that reflects ante�ro�superiorly (temporal�facial part), laterallycrossing the large vessels proceeding throughthe gland (external carotid artery and retro�mandibular vein). The exit point of the facialnerve from the stylomastoid foramen can easi�ly be defined using the internal projection ofthe tragus as “pointer”. The exit point usuallylies centrally between the “pointer” and thestylohyoidal process. The subdivision of thefacial nerve into the two main�branches can bedefined according to Eyries (1972) as follows;

9

8

7

6

5

4

3

2

1

19

18

17

16

15

14

13

12

11

10

1 — Papilla salivaria buccalis; 2 — Mandibula; 3 — Tonsilla pa�latina; 4 — Pharynx; 5 — Spatium peripharyngeum; 6 — Proc.styloideus; 7 — A. carotis int.; 8 — N. vagus (X); 9 — N. glos�sopharyngeus (X) and N. hypoglossus (XIII); 10 — V. jugularisint. 11 — M. buccinator; 12 — Ductus parotideus; 13 — M. mas�seter; 14 — M. pterygoideus med. 15 — Fascia parotidea; 16 —N. facialis (VII); 17 — V. retromandibularis; 18 — A. carotis ext.;19 — Parotid gland

24


the first line runs from the tragus�pointer to themandibular angle (T�G in Fig. 2�3) the secondfrom the mastoidal process to the middle of themandibular ramus (M�M in Fig. 2�3). The in�tersection of these two lines (F in Fig. 2�3)marks in about 70% of cases the point in whichthe facial nerve divides within the parotis.

The superior main�branch of the facial nervedivides rapidly into relatively thin, closely ap�proximated temporal and frontal branches,which leave the parotid gland below the zygo�matic arch, over which they then cross diago�nally to reach the mimetic muscles near the lineof the hair, for which they are responsible.

The distance from the external ear and tra�gus varies, but is usually under 1.5—2 cm(M.E. Wigand et al., 1997) (Fig. 2�4). In or�der to avoid injury to the Facial nerve oneshould choose an incision which preserves thesubcutaneous fat�pad lying laterally to the tem�poral fascia.

The two main branches, and the finerbranches of the facial nerve; which anastomosewith one another to form a coarsely meshednetwork (parotid plexus); lie within the sameplane in the parotid gland and divide the glandinto two layers. The superficial layer is relative�ly thin, the deeper layer together with the ret�romandibular fossa portion of the gland takesmuch more space. The temporal�facial part ofthe VII nerve divides immediately into numer�ous branches, which run diagonally to the su�perior margin of the parotid gland where theyexit at the parotid fossa. The branches reach�ing the farthest cranially are the temporal�fron�tal branches which cross over the zygomaticarch and then approach the underside of the au�ricular anterior muscle, the frontal belly of theoccipital frontal muscle and the orbicular mus�cle of eye (superior parts until the palpable fis�sure), which they innervate (somatomotoric). Asecond group builds the zygomatic branches,which run at the height of the zygomatic archand supply the inferior part of the orbicularmuscle of the eye and zygomatic muscles.

The first divisions of the inferior main facialbranch (cervical�facial part) are the buccalbranches of the facial nerve, which lie near themasseter muscle, and irradiate inferiorly at the

Fig. 2�3. The localization of the main facial trunk andits point of bifurcation into the two main branches asdescribed from Eyries (M.E. Wigand et al., 1997)

TG

F

MM

Fig. 2�4. The path of the temporal�frontal branches ofthe facial nerve in the pre�auricular region. Marked arethe variable pathways of the temporal (T) and thefrontal (F) branches. Two dimensions where measured(a = distance between lateral cantus and superior mar�gin of auricle, b = distance between lateral cantus andtragus�helix notsch) (M.E. Wigand et al., 1997)

mimetic muscles of the inferior facial region(orbicular and buccinator muscles, and levatormuscle at the angle of mouth). The superiorbranch of this fan. shaped system, also known

a

b

T F

68


CHAPTER OUTLINE

INTRODUCTION ............................................ 68

INTRAOPERATIVE MONITORINGOF THE FACIAL NERVEIN PAROTID GLAND SURGERY ...................... 68

EXTRA�CAPSULAR SECTION ......................... 71

DATA UNDERPINNING THE PRACTICEOF EXTRA�CAPSULAR SECTION ................... 73

EXTRA�CAPSULAR DISSECTIONOF THE DISCRETE PAROTID LUMP .............. 73

Discussion ............................................... 74

PAROTIDECTOMY ......................................... 74

SUBMANDIBULAR SIALADENECTOMY ........... 81

References ................................................... 83

INTRODUCTION

Salivary gland surgery for benign tumoursis a traditional surgery which was not changedduring decades. The direction in all the surgi�cal fields is traced towards minimal and less in�vasive procedures.

The aim of this chapter is to review the newconservative procedures and the traditionalsurgery for benign surgery of the major salivary

glands. We also include in this chapter intra�operative facial nerve monitoring due to theimportance and the needs of these innovativetechniques.

INTRAOPERATIVEMONITORING

OF THE FACIAL NERVEIN PAROTID GLAND

SURGERY

Intraoperative neurophysiological monitor�ing has been used with an increasing frequen�cy in thyroid gland surgery as well as in cere�bellopontine angle surgery. Some authors alsorecommend the regular use of neuromonitoringin middle ear surgery for protection of the fa�cial nerve.1

Concerning parotid gland surgery there arestill many divergent opinions. Whereas manyauthors consider the intraoperative monitoringof the facial nerve useful in difficult cases suchas revisional surgery there is still a lot of dis�cussion about its necessity in routine parotidgland surgery.2, 3

C H A P T E R 4Conservative and Traditional SurgicalApproaches to Benign MajorSalivary Gland TumoursMark McgurkHeinrich IroJohannes ZenkOded Nahlieli

69

• Chapter 4. Conservative And Traditional Surgical Approaches... •

According to current studies, the rate ofpostoperative permanent facial paresis follow�ing removal of benign parotid tumours is 3 to5% and the rate of temporary postoperativefunctional deficits of the facial nerve is as highas 8 to 65%.3, 4 Even temporary paresis car�ries — not to mention the esthetic disfigure�ment of the patient — the risk of permanentcorneal damage due to insufficient eyelid clo�sure and ought to be avoided if possible.

The intraoperative neuromonitoring of thefacial nerve facilitates the identification of thenerve and allows a constant supervision of neu�ral function.4, 5 Arguments frequently men�tioned against the routine use of neuromonitor�ing are the additional time required and thepossible lack of accuracy. Some authors fearthat the routine use of neuromonitoring maylead to a situation where younger surgeonswould not be able anymore to perform parotidsurgery without monitoring or where surgeonsnot using a monitoring device may exposethemselves to possible legal problems.3 Otherauthors are afraid that the surgeon, due to afalse sense of security, might be tempted towork faster and not careful enough.

Facial nerve monitoring may be performedwith different electromyography devices. TheNeurosign�100 (Inomed) and the Nerve Integ�rity Monitor�2 (Xomed�Treace) are frequent�ly used systems. Both units have two channelsand an electric stimulator. After the patient isunder general anesthesia, the unipolar needleelectrodes are inserted subcutaneously in thefrontalis muscle, the orbicularis oculi muscle and

the orbicularis oris muscle (Figs. 4�1 and 4�2).The electrodes are connected with the pream�plifier (headbox) and the monitoring device

Fig. 4�1. Monopolar needle electrodes and coaxial bi�polar stimulation probe used in facial nerve monitoring

Fig. 4�2. Needle electrodes inserted in the frontalis,the orbicularis oculi and the orbicularis oris muscle

(Figs. 4�3 and 4�4) and the stimulation probeis attached to the monitoring unit. During sur�gery a continuous recording of spontaneousmuscle activity takes place. The muscle activi�ty can be visually monitored on the EMG de�vice itself and on an additional monitor. In ad�

Fig. 4�3. Electrodes connected to the preamplifier(headbox)

70


dition to that there is a loudspeaker where themeasured activity is displayed as an audible sig�nal during surgery.

It is important to inform the anaesthesiolo�gist not to administer muscle relaxants after in�tubation of the patient.

Intraoperative electric stimulation of thefacial nerve is done with a bipolar coaxial probeunder constant�current conditions. Usuallyindividual stimuli (duration 0.1 ms, frequency 3Hz) with a stimulation intensity between 0.5and 3 mA are used. The use of a monopolar stim�ulation probe is also possible, but it requires foranother electrode to be placed on the edge of thesurgical field. However, this leads to a ratherwidespread electrical field and makes an exactlocalization of the nerve difficult.

The stimulation of the nerve results in aclearly visible wave on the monitor (Fig. 4�5).False�negative responses, meaning stimulationof an intact nerve without getting signals onthe EMG monitor are not described in moststudies.5 False�positive responses, meaningmeasurements of muscle activity after stimula�

tion of structures other than nerves are mainlyseen when using a monopolar stimulation probedue to the widespread electrical field.5 Due tothese reasons our recommendation is to use abipolar stimulation probe.

The set�up of the monitoring device can bedone either by the surgeon himself or by an as�sistant. Since the surgeon has constant acous�tic and visual control over the spontaneous andevoked muscle activity, there is no need for thepresence of an assistant as additional personduring the surgery.

The anatomical variability of the localiza�tion of the facial nerve in the parotid gland andits possible dislocation by the tumour make pa�rotid gland surgery more difficult and requireexcellent anatomic knowledge and subtle tech�nique of preparation.

A frequently used method for localization ofthe facial nerve and for its intraoperative surveil�lance was the observation of facial movementsafter accidental mechanical irritation of the nerveor after electrical stimulation with battery�oper�ated hand�held stimulators. This requires a con�tinuous surveillance of the patient’s face. More�over irritiations of the facial nerve during surgeryfrequently lead to mechanically evoked muscleactivities which can be monitored by the EMGdevice as single or multiple discharges (bursts ortrains, Fig. 4�6) but do not cause any contractionin the region of the mimic muscles and couldtherefore not be detected by observation of the

Fig. 4�4. EMG unit with monitor

Fig. 4�5. EMG signal on the monitor with stimulationof the main stem of the facial nerve

71

• Chapter 4. Conservative And Traditional Surgical Approaches... •

Fig. 4�6. Mechanically evoked muscle activity duringsurgery

face. Even these subclinical mechanical irritationsmay cause nerve damage. Monitoring of the fa�cial nerve informs the surgeon about these dis�charges and helps to avoid nerve damage.

One of the main arguments against facialnerve monitoring during routine surgery is theincreased amount of time and personnel. Theset�up of the monitoring device does not takemore than five minutes. According to our ex�perience, an additional assistant for observationof the neurophysiologic unit during surgery isnot necessary. Even if some authors demand thecontinuous presence of a monitoring specialistduring surgery, we think this can be easily doneby the surgeon himself.3

The argument of additional manpower is notapplicable and should not be used against theroutine use of neuromonitoring. According toour experience, the small amount of additionaltime necessary for the set�up is compensated bya shorter duration of surgery.5 Complications ofneuromonitoring such as skin burns around thesubcutaneously inserted needle electrodes dueto malfunction of the monitoring device are for�tunately extremely rare.6

Neuromonitoring of the facial nerve is abso�lutely necessary in cases of extracapsular dissec�tion of circumscript tumours of the parotidgland. If a parotid tumour is to be removed with�out exposing the main stem of the facial nerve,it is indispensable to use repeated and carefulstimulation around the tumour to localize andpreserve small nerve branches (Fig. 4�7).

Fig. 4�7. Localization of small nerve branches by stim�ulation around the tumor

In our opinion there is no valid reason torenounce on safety benefits provided by theroutine use of facial nerve monitoring in allcases of parotid gland surgery. Two retrospec�tive studies have shown a better postoperativefacial nerve function in patients when facialnerve monitoring was used.5, 7 Over time thesurgeon gets more familiar with the technique,which leads on the one hand to a shorter set�up time and on the other hand to an easier as�sessment of the evoked EMG activity whichcan then easily be differentiated from artefacts(for instance discharges of electrostatic metal�lic instruments).

It goes by itself that neuromonitoring willnever replace the anatomical knowledge andthe surgical experience of the physician nor thesufficient exposition of the surgical field.

EXTRA�CAPSULAR SECTION

The fear in adopting a more conservativesurgical approach to the apparent benign parot�id tumour (discrete parotid lump) arises fromthe fact that pleomorphic adenoma has a repu�tation for recurrence and that this techniquemay lead to a recurrence. There is also the riskthat a surgeon may inadvertently blunder intoa malignant neoplasm masquerading as a be�nign lump. These two concerns have hinderedthe adoption of minimally invasive techniquesreadily accepted in other surgical disciplines.

227

• Chapter 11. Parotid Trauma Management •

CHAPTER OUTLINE

INTRODUCTION .......................................... 227

DIAGNOSIS ................................................ 227

TREATMENT ............................................... 228

COMPLICATIONS ........................................ 229

CONCLUSION ............................................. 233

References ................................................. 233

INTRODUCTION

Facial trauma and especially parotid traumamay manifest in many clinical symptoms suchas: facial nerve injuries, parotid gland and ductinjuries and further involvement of the under�lying anatomic structures; auditory canal andthe temporomandibular joint (TMJ). It was de�scribed by Lewis et. al. that 0.21% of lacera�tions in the facial region resulted in a parotidduct or gland injury.1

The mechanism of trauma is of great impor�tance as well as the site and depth of the inju�ry. Contusion, hematoma or laceration of thegland or duct can cause for complication tooccur. Although the incidence of parotid glandand duct trauma is fairly low, all maxillofacial

surgeons should be aware of such injuries andbe capable of recognizing the symptoms. Theimmediate and late complications if not ob�served and treated accordingly are very diffi�cult managed in the delayed period, these in�clude traumatic sialocele and fistula.

Parotid gland and duct may not be the soleinflicted organ in the facial trauma, howeverunlike other injuries such as facial palsy or TMJdysfunction, it is sometimes difficult to diag�nose this kind of injury. Therefore attention isneeded when dealing with such trauma. Theexact trauma site is highly important whetherit is the capsule of the gland or the duct it self,and this in turn will render the approach to beeither a surgical or a conservative one.

DIAGNOSIS

The recognition and treatment of a traumato the parotid gland or duct in time of patientadmission starts with review of the injured site,the occurrence of saliva in the injured site willbe indicative for laceration. Squeezing thegland in order to produce salivary flow via theStensen’s orifice and localization and visualiza�

CHAPTER 11

Parotid Trauma Management

Oded NahlieliTal BarMichael Vaiman

228


tion of the duct by insertion of probe or cannu�la through the oral orifice is the second mostimportant step. When there is a doubt regard�ing the duct integrity it is advised to use isotonicsaline solution. Once considered as a dye solu�tion, methylene�blue is not indicated nowadays.

Through out the initial diagnosis, care mustbe taken for the facial nerve function.

Radiology assessment for parotid trauma isnot indicated (excluding the use of parotid sia�logram when possible), but can be used in or�der to exclude accompanying trauma of adja�cent structures e.g.; TMJ, auditory canal.

TREATMENT

Two approaches are used each with its ownindications.

When the parotid gland parenchyma is onlycontused the conservative or non�surgical ap�proach is indicated with the use of antisial�ogogues, elastic bandages, this will induce hy�pofunction of the gland.2 When hematomaoccurs and Stensen’s duct occlusion is possible,probing and bujjinage are indicated, thus main�taining ductal competence.

However, when a laceration of the gland orduct occurs, a surgical approach is mandatory,3

this depends upon the exact location of the lac�eration; in the glandular region, over the mas�seter muscle or anterior to the masseter muscle.4

The former injury is treated by closure ofthe capsule, those over the masseter are treat�ed with a direct repair of the duct, and the lat�ter are dealt with either repair of the duct or anew orifice formation.5, 7

When the aforementioned injuries are sus�pected, one should follow these suggested ac�tions; insertion of a cannula to the Stensen’sduct (intraorally) if a deep skin laceration ispresent, direct visualization of the cannula as itpierces the duct is indicative of ductal laceration.If the cannula is not seen in the injury site, asaline solution is administered via the cannula,care must be taken not to over fill the gland (not

more than 4 cc of fluid per gland). The presenceof fluid in the injury site is indicative of ductal/glandular laceration. The amount of fluid willindicate whether the main duct is transected(large amount of fluid) or the capsule (lesseramount of fluid).

The treatment of each laceration is dealtaccording to its anatomical location and theability of the surgeon to locate both ends of theduct in order to perform anastomosis.

A laceration close to the oral cavity is treat�ed by suture and if needed a stent is insertedto maintain ductal potency.

For the measures of the stent we advise theuse no more then 1 mm (3 fr) diameter and 8—10 cm in length.

Lacerations found proximally are treated byexploring the stumps (both proximal and dis�tal) with care taken not to harm the facialnerve. The stumps are approximated, suturedwith nylon (8—0, 9—0) sutures. A stent is in�serted for a period of 1 month.

If direct approximation is not achieved, agraft should be considered.6

In addition an active drain inserted in theinjured gland will prevent saliva accumulation,thus sialocele formation is sustained.

In cases of torn duct with inability to ap�proximate the stumps, a cannula or a stent areinserted in the proximal part of the duct andthe distal part of the stent is advanced to theoral cavity. In cases of parotid capsule lacera�tion, the capsule is inspected and sutured, apressure dressing is applied for 48 hours, stentinsertion is advised for 1 month and an activedrain for a few days.

When the proximal part of the duct is notidentified easily, the use of sialoendoscope is ad�vised as follows:

A lacrimal probe is inserted in the distal part;the skin overlying the duct is approximated andthe exact exit point of the probe will indicate therelative location of the proximal part of the duct.This area will now be inspected with the sialoen�doscope for the exact duct location and furtheranastomosis will take place.

229

• Chapter 11. Parotid Trauma Management •

COMPLICATIONS

Sialocele and parotid fistula formation arethe most common complications occurring inparotid trauma.

Both states are managed by either decreas�ing the salivary flow or diversion of salivary flowto the oral cavity. Gland atrophy and stricturesare considered as late complications and aredealt accordingly (see relevant chapters).

Some authors report up to 58% of the pa�tients suffers from sialocele and 30% from fis�

tula2. All received “nothing�by�mouth” treat�ment and were cured eventually.

A sialocele is the accumulation of salivamanifesting in a facial swelling, thus salivary se�cretion without the proper drainage. The diag�nosis is done with aspiration, which demon�strates high amylase containing fluid.

If sialocele appears immediately, re�explora�tion is indicated.

Late formation of this phenomenon can betreated with repeated aspirations, continuouspressure, antisialogogues, radiotherapy, pa�

230


Fig 11�1. A — The facial area is divided according to Van�Sickels4 to 3 parts when dealing with a parotid glandand duct trauma. The horizontal line depicts the course of the Stensen’s duct. B&C — A diagram of a laceratedStensen’s duct and the approximation and suturing of the stumps

C

A B

A

Buccinatormuscle

Massetermuscle

Parotidgland

Proximal end oftransected duct

Silastictube

Distal end oftransected duct

Parotidduct

Parotidgland

Buccinatormuscle

Massetermuscle

Distal portion oftransected duct

Parotidgland

Silastictube

Proximal portionof transected

duct

Documents

Cornerstones, Milestones, Steppingstones and Stones … · The earliest refrences to saliva medical con ditions probably originate in the ancient Me sopotamia, in the 7th century