1126 LINGUAL FLAP RETRACTION FOR THIRD MOLAR REMOVALeither be bone removal distal to the third molar orwhere the crown of the third molar would need to besectioned. The technique was not used when teethcould be elevated whole, either without any boneremoval, or with buccal bone removal only. In somecases the decision to use lingual retraction was madeintraoperatively if crown sectioning or distal boneremoval was found to be necessary. Patients werestudied for access and ease of tooth removal and alsofor the presence of any postoperative lingual orchorda tympani nerve involvement. All patients werequestioned 1 week postoperatively regarding lingualnerve sensory impairment or taste impairment. Pa-tients reporting a change were tested with von Freys FIGURE 2. The double-ended Walters lingual retractor (KLS-Martin, order no. 92-380-00) with a Molt bone curette (above) and a Ward’shairs.5 Human Research Committee approval was ob- periosteal elevator (below).tained for this study. Pogrel and Goldman. Lingual Flap Retraction for Third Molar In the technique used, an incision was made down Removal. J Oral Maxillofac Surg 2004.the external oblique ridge of the mandible approxi-mately 1.5 to 2 cm in length down to the distobuccal line angle of the lower second molar, and then a releasing incision was made into the buccal sulcus (Fig 1). A buccal ﬂap was raised and an appropriate buccal retractor placed (usually a Minnesota-type re- tractor). The lingual ﬂap was then raised by means of a Molt or Ward’s periosteal elevator (ie, a spoon- shaped elevator). Once an adequate lingual ﬂap was raised, a Walter’s lingual retractor was placed (KLS- Martin LP, Jacksonville, FL). This is a double-ended instrument (one end for the left side, one end for the right side) shaped to ﬁt the lingual contour of the mandible of the third molar region, broad enough to protect the whole area in which bone may be re- moved, and also has a small lip on it that engages the medial oblique ridge and prevents the retractor from migrating too deeply (Figs 2, 3). Results In the 250 patients studied there were no cases of permanent lingual nerve injury. There were 4 cases of transient lingual nerve injury consisting of sensation only (not taste). These 4 cases were tested with von Frey’s hairs,5 and in 3 of the cases the difference in von Frey’s hairs between the normal side and the abnormal side was 3 von Frey’s hairs or less,6 denot- ing a minor loss of sensation. In all 3 of these cases the paresthesia resolved within 21 days. In the fourth case, the difference in feeling with von Frey’s hairs between the normal and abnormal side was 7 hairs, which indicates a more substantial loss of sensation, and in this case normal sensation did not return for 2 months. On review of this case there appeared to beFIGURE 1. Diagram of the standard incision used to raise buccaland lingual ﬂaps (right side). nothing abnormal about the case that might havePogrel and Goldman. Lingual Flap Retraction for Third Molar given this result. Ease of access was conﬁrmed and isRemoval. J Oral Maxillofac Surg 2004. shown in the clinical photograph which shows that
POGREL AND GOLDMAN 1127FIGURE 3. A, Lingual retractor in place viewed from the buccal side showing excellent access to the tooth and surrounding bone. B, Lingualretractor in place viewed from the lingual aspect showing excellent coverage of the lingual tissues and the lip (arrow), which engages the internaloblique ridge and prevents the retractor migrating inferiorly. Also note the contour of the retractor that follows the contour of the lingual plate in thethird molar region.Pogrel and Goldman. Lingual Flap Retraction for Third Molar Removal. J Oral Maxillofac Surg 2004.both the crown of the tooth and the bone surround- This study suggests a transient lingual paresthesiaing the third molar are fully displayed both buccally rate of 1.6% and 0% permanent lingual nerve damage,and lingually (Fig 4). With this retractor in place no using this particular lingual retraction technique.additional tongue retractor is required. Figure 5 isinteresting in that it does show the results after the Discussionthird molar was removed in 1 case and shows thatthere has been a minor fracture of the lingual plate Since the 1980s most protocols for removal of thirdwith loss of a small piece of the superior lingual plate molars have recommended a buccally based ﬂap with(arrowed). It can be envisaged that if a lingual retrac- buccal retraction only and removal of teeth with ator had not been placed in this region, and this small drill from the buccal approach. It is recommendedﬂake of bone had been displaced, it could have dam- that impacted teeth are sectioned multiply to removeaged a highly placed lingual nerve. This may show the all fragments without the necessity of removing distaladditional value of lingual retraction in that it not only or lingual bone.1-3 A major reason for this is an at-protects the lingual nerve from damage from instru- tempt to avoid lingual nerve damage while removingmentation, but also from minor fractures of the lin- the teeth. It has been realized since the mid 1980sgual plate. that in around 15% to 20% of patients the lingual FIGURE 5. View of the lingual plate after tooth removal. Note theFIGURE 4. Lingual retractor in place clinically showing excellent small fracture of the lingual plate (arrow) that could have inadvertentlyvisualization and access to bone and tooth removal. Also note the lip damaged a lingual nerve that was superiorly positioned, had theof the retractor engaging the internal oblique ridge. lingual retractor not been in place.Pogrel and Goldman. Lingual Flap Retraction for Third Molar Pogrel and Goldman. Lingual Flap Retraction for Third MolarRemoval. J Oral Maxillofac Surg 2004. Removal. J Oral Maxillofac Surg 2004.
1128 LINGUAL FLAP RETRACTION FOR THIRD MOLAR REMOVALnerve lies in an abnormally high position and may be clearly where one is drilling, and the lingual nerve islevel with or superior to the crest of the lingual protected.4,11,16,37,38 Robinson and Smith39 stated thatplate.7-10 To avoid damage to a lingual nerve in this permanent lingual nerve injury often results from di-aberrant position, it has been recommended that all rect damage from a rotating bur. In a more recentincisions are made well to the buccal side of the ridge, article, Robinson et al40 found that the affected nervesand only a buccal ﬂap is elevated and no attempt is were always found trapped in scar tissue and some-made to elevate a lingual ﬂap. Similarly, all bone times expanded to form a neuroma. Complete divi-removal is recommended to be carried out from the sion of the nerves was evident in approximately 50%,buccal side and, following removal of the tooth, ex- and small fragments of metal were sometimes foundtreme care should be taken in removing follicular embedded within the epineurium of scar tissue, pre-remnants on the lingual side of the socket, and if the sumably having been shaved from the lingual retrac-socket is to be sutured postoperatively, there should tor (Howarth’s elevator, a narrow elevator used inonly be very superﬁcial sutures on the lingual side. All much of Europe) during the initial operation. Thethe above are recommended to avoid damage to the technique described in this article is not the same aslingual nerve. Historical studies have shown variable the lingual split technique where lingual bone is de-results for lingual nerve damage following removal of liberately removed with a chisel and the tooth deliv-lower third molars with temporary lingual nerve dam- ered lingually.41 The technique described in this arti-age ranging from 0% to 22%, and permanent damage cle involves lingual retraction only, but with boneranging from 0% to 2% of all lower third molar remov- removal from the buccal side with a drill. The weak-als, depending on a number of factors, including the ness of this technique in the past has been that thetechniques used.11-32 Several studies, however, have retraction itself was often provided by a periostealtended to show that since these policies were elevator such as a Howarth’s elevator, which is poorlyadopted in the late 1980s, there has been no signiﬁ- designed for the purpose in that it is too narrow tocant decrease in the incidence of lingual nerve dam- protect the whole of the lingual nerve, has sharpage following third molar removal, which has vari- edges that themselves can damage the nerve, and isously been estimated between 0.2% and 1.6% of all incorrectly shaped to ﬁt the lingual aspect of thelower third molars having some degree of change of mandible.12 Nevertheless, studies with this techniquelingual nerve sensation postoperatively.13-15,18,19,33,34 are variable, but do tend to show that approximatelyAlthough it is known that most cases recover sponta- 11% of patients may have some form of transientneously, and one study shows that 83% of lingual paresthesia of the tongue, but there are virtually nonerve injuries resolve spontaneously,35 there does not cases of permanent nerve involvement.11,15,22,25 Thisappear to be any signiﬁcant decrease in the number ofcases of permanent lingual nerve involvement. Cer- would suggest that there may be some traction inju-tainly if medicolegal experience is any guide, the ries of the nerve, but they are still mild and transient.number of cases has certainly not decreased (L. Esta- Another issue has been that the Howarth or similarbrooks, Oral and Maxillofacial Surgeons National In- elevator can be placed or can migrate too deeply andsurance Company, personal communication, 2003). A can go down far enough to affect the mylohyoidrecent study in California (where replies were ob- nerve and cause a paresthesia (usually temporary)tained from 86% of all practicing oral and maxillofa- over the appropriate area innervated by the mylohy-cial surgeons in California), where the vast majority of oid nerve.42 Because of problems with the Howarthpractitioners use a buccal approach, showed that 53% elevator, the issue of lingual nerve retraction has be-of oral and maxillofacial surgeons were aware of a come controversial.39,43-50case of lingual nerve damage that had occurred with To circumvent these problems, a new lingual re-them during the preceding year (temporary and per- tractor (KLS Martin LP, No. 92-380-00) and compli-manent). Additionally, 46% of all the oral and maxil- mentary periosteal elevators were designed in the midlofacial surgeons studied were aware of having caused 1990s by Dr Hugh Walters, a consultant oral anda permanent lingual nerve injury following third mo- maxillofacial surgeon in the United Kingdom (sincelar removal during their professional lifetime. In 57% deceased), which appears to eliminate these potentialof the cases, the practitioner involved had no idea of problems.45 The right- and left-sided periosteal eleva-the actual cause of the injury.36 An alternative tech- tors are designed to be used with the lingual retractornique is to practice elevation and retraction of a to initially retract the lingual ﬂap. In fact, we havelingual ﬂap, and the placement of a retractor down found the periosteal elevators awkward to use be-the lingual periosteum of the mandible to improve cause the actual working tip is at right angles to theaccess to the area and also to protect the lingual handle, making its moment of force inefﬁcient. Anerve. Bone can still be removed with the drill in the straight periosteal elevator is much more efﬁcient andnormal way, but with better access one can see more effective and an elevator with a spoon-shaped tip,
POGREL AND GOLDMAN 1129such as a straight Molt bone curette or Ward’s eleva- from drills, instruments, or inadvertent lingual platetor, adapts just as well to the shape of the lingual or tooth fracture or displacement. These may be re-plate. The elevator itself is then placed, and it is broad sponsible for the cases of permanent nerve involve-enough to protect the whole aspect of the lingual ment seen following lower third molar removal. Itnerve in the third molar region, has no sharp edges on may be appropriate to re-examine the techniques andit, and has a notch that ﬁts into the internal oblique principles of lingual ﬂap elevation and retraction.ridge of the mandible and prevents the instrumentfrom slipping too deeply and possibly involving themylohyoid nerve. It allows excellent access to the Referencesthird molar and protects the lingual tissue from drills, 1. Alling RD, Alling C: Part 1, Mandibular third molars buccal-instruments, or lingual plate fractures. An initial study occlusal approaches, in Alling CC, Helfrick JF, Alling RD (eds):using this retractor showed that in the ﬁrst 100 cases Impacted Teeth. Philadelphia, PA, Saunders, 1993, pp 150-202 2. Khanuja A, Powers MP: Surgical management of impactedthere was only 1 patient with a transient paresthesia teeth, in Fonseca RJ (ed): Oral and Maxillofacial Surgery. Vol 1.that resolved within 3 weeks.51 Philadelphia, PA, Saunders, 2000, pp 259-268 Conceptually, the idea of lingual nerve identiﬁca- 3. Peterson LJ: Principles of management of impacted teeth, in Peterson LJ, Indresano AT, Marciani RD, et al (eds): Principlestion and retraction mirrors more closely what hap- of Oral and Maxillofacial Surgery, vol 1. Philadelphia, PA, Lip-pens in other surgical procedures, whereby if one pincott, 1992, pp 103-117wishes to avoid damaging a certain structure, one ﬁrst 4. Gulicher D, Gerlach KL: Sensory impairment of the lingual and inferior alveolar nerves following removal of impacted mandib-identiﬁes the structure and retracts it out of the way, ular third molars. Int J Oral Maxillofac Surg 30:306, 2001before proceeding with the surgery. As stated by 5. Weinstein S: Tactile sensitivity in the phalanges. Percept MotorSeward,52 “In no other surgical situation is it consid- Skills 14:351, 1962 6. Pogrel MA: The results of microneurosurgery of the inferiorered appropriate to operate close to a valuable nerve alveolar and lingual nerve. J Oral Maxillofac Surg 60:485, 2002and not to identify it and protect it from damage.” 7. Kiesselbach JE, Chamberlain JE: Clinical and anatomic obser-Additionally, in oral and maxillofacial surgery, such a vatory on the relationship of the lingual nerve to the mandib- ular third molar. J Oral Maxillofac Surg 42:565, 1984technique would actually improve access to the third 8. Pogrel MA, Renaut A, Ammar A: The relationship of the lingualmolar region, enabling bone and tooth removal to nerve to the mandibular third molar region: An anatomic study.proceed more accurately, and would prevent damage J Oral Maxillofac Surg 53:1178, 1995 9. Miloro M, Halkias LE, Slone HW, et al: Assessment of the lingualto the lingual nerve by a drill, chisel, or by any frag- nerve in the third molar region using magnetic resonancements of bone and tooth becoming displaced during imaging. J Oral Maxillofac Surg 55:134, 1997surgery. 10. Behnia H, Kheradvar A, Shahrokhi M: An anatomic study of the lingual nerve in the third molar region. J Oral Maxillofac Surg However, meta-analysis has failed to show any dif- 58:649, 2000ference in permanent lingual nerve injury rates 11. Schultze-Mosgau S, Reich RH: Assessment of inferior alveolarwhether a lingual retractor was used or not.53 It is also and lingual nerve disturbances after dentoalveolar surgery, and of recovery of sensitivity. Int J Oral Maxillofac Surg 22:214,recognized that the only 2 controlled trials to date 1993between lingual retraction and protection and a 12. Rood JP: Permanent damage to inferior alveolar and lingualpurely buccal approach showed no difference in lin- nerves during the removal of impacted mandibular third mo- lars: Comparison of two methods of bone removal. Br Dent Jgual nerve injury rates. However, these studies were 172:108, 1992conﬁned to 300 patients each,54,55 and all other stud- 13. Rud J: The split bone technique for removal of impactedies have involved a relatively small number of pa- mandibular third molars. J Oral Surg 28:416, 1970 14. Van Gool AV, Ten Bosch JJ, Boering G: Clinical consequencestients. Because it is now realized that permanent lin- of complaints and complications after removal of the mandib-gual nerve involvement may occur in approximately 1 ular third molar. Int J Oral Surg 6:29, 1977in 10,000 lower third molar removals in California,36 15. Bruce RA, Frederickson GC, Small GS: Age of patients and morbidity associated with mandibular third molar surgery.it is acknowledged that such a study could only show J Am Dent Assoc 101:240, 1980a statistically signiﬁcant difference if many thousands 16. Rood JP: Lingual split technique. Damage to inferior alveolarof patients were included in a study. Indeed, it would and lingual nerves during removal of impacted mandibular third molars. Br Dent J 154:402, 1983involve 30,000 patients to arrive at a statistically sig- 17. Hochwald DA, Davis WH, Martinoff J: Modiﬁed distolingualniﬁcant absolute risk reduction. splitting technique for removal of impacted mandibular third Lingual ﬂap elevation and lingual ﬂap retraction molars: incidence of postoperative sequelae. Oral Surg Oral Med Oral Pathol 56:9, 1983with a broad retractor may be suitable techniques to 18. Rud J: Re-evaluation of the lingual split bone techniques forre-evaluate with regard to lower third molar removal. removal of impacted mandibular third molars. J Oral Maxillo-Although the actual raising of the lingual ﬂap and facial Surg 42:114, 1984 19. Goldberg MH, Nemarich AN, Marco WP: Complications afterplacement of a lingual retractor can theoretically mandibular third molar surgery: A statistical analysis of 500cause a traction injury to the lingual nerve, it appears consecutive procedures in private practice. J Am Dent Assocfrom the present study that these are transient and of 111:277, 1995 20. Sisk AL, Hammer WB, Shelton DW, et al: Complications follow-no long-term consequence. Conversely, this tech- ing removal of impacted third molars: The role of the experi-nique may protect the nerve from inadvertent damage ence of the surgeon. J Oral Maxillofac Surg 44:855, 1986
1130 LINGUAL FLAP RETRACTION FOR THIRD MOLAR REMOVAL21. Wofford DT, Miller RI: Prospective study of dysesthesia follow- 38. Seward GR, Harris M, McGowan DA: Surgical removal of roots ing odontectomy of impacted mandibular third molars. J Oral of impacted teeth, in Seward GR, Harris M, McGowan DA Maxillofac Surg 45:15, 1987 (eds): Killey & Kay’s Outline of Oral Surgery (ed 2). Bristol,22. Mason DA: Lingual nerve damage following lower third molar Wright, 1987, pp 61-62 surgery. Int J Oral Maxillofac Surg 17:290, 1988 39. Robinson PP, Smith KG: Lingual nerve damage during lower23. Middlehurst RJ, Barker GR, Rood JP: Postoperative morbidity third molar removal: A comparison of two surgical methods. Br with mandibular third molar surgery: a comparison of two Dent J 180:456, 1996 techniques. J Oral Maxillofac Surg 46:474, 1988 40. Robinson PP, Loescher AR, Smith KG: A prospective, quantita-24. Blackburn CW, Bramley PA: Lingual nerve damage associated tive study on the clinical outcome of lingual nerve repair. Br J with the removal of lower third molars. Br Dent J 167:103, Oral Maxillofac Surg 38:255, 2000 1989 41. Ward TG: The split bone technique for the removal of lower25. Von Arx DP, Simpson MT: The effect of dexamethasone on third molars. Br Dent J 101:297, 1956 neurapraxia following third molar surgery. Br J Oral Maxillofac 42. Tier GA, Rees RT, Rood JP: The sensory nerve supply to the Surg 27:477, 1989 tongue: A clinical reappraisal. Br Dent J 157:354, 198426. Carmichael FA, McGowan DA: Incidence of nerve damage 43. Greenwood M, Langton SG, Rood JP: A comparison of broad following third molar removal: A West of Scotland Oral Surgery and narrow retractors for lingual nerve protection during Research Group study. Br J Oral Maxillofac Surg 30:78, 1992 lower third molar surgery. Br J Oral Maxillofac Surg 32:114,27. Absi EG, Shepherd JP: A comparison of morbidity following the 1994 removal of lower third molars by the lingual split and surgical 44. To EW, Chan FF: Lingual nerve retractor. Br J Oral Maxillofac bur methods. Int J Oral Maxillofac Surg 22:149, 1993 Surg 32:125, 199428. Chiapasco M, De Cicco L, Marrone G: Side effects and compli- 45. Walters H: Reducing lingual nerve damage in third molar sur- cations associated with third molar surgery. Oral Surg Oral Med gery: A clinical audit of 1350 cases. Br Dent J 178:140, 1995 Oral Pathol 76:412, 1993 46. Walters H: Lingual nerve damage during lower third molar29. Malden NJ, Maidment YG: Lingual nerve injury subsequent to removal: A comparison of two surgical methods. Br Dent J wisdom teeth removal–A 5-year retrospective audit from a high 181:163, 1996 street dental practice. Br Dent J 193:203, 2002 47. Mason DA: “To retract or not to retract.” Br Dent J 168:94,30. Renton T, McGurk M: Evaluation of factors predictive of lingual 1990 nerve injury in third molar surgery. Br J Oral Maxillofac Surg 48. Robinson P: To retract or not to retract. Br Dent J 168:5, 1990 39:423, 2001 49. Shotts N: It ain’t what you do... Br Dent J 181:121, 199631. Valmaseda-Castellon E, Berini-Aytes L, Gay-Escoda C: Lingual 50. Christian C: Retractors have their detractors. The Dentist Nov: nerve damage after third lower molar surgical extraction. Oral 42, 1992 Surg Oral Med Oral Pathol Oral Radiol Endod 90:567, 2000 51. Goldman KE, Pogrel MA: Lingual ﬂap retraction in third molar32. Bataineh AB: Sensory nerve impairment following mandibular surgery. J Oral Maxillofac Surg 56:82, 1998 (suppl 4) third molar surgery. J Oral Maxillofac Surg 59:1012, 2001 52. Seward GR: Protecting the lingual nerve from damage. Br J Oral33. Schwartz LJ: Lingual anesthesia following mandibular odontec- Maxillofac Surg 39:76, 2001 tomy. J Oral Surg 31:918, 1973 53. Pichler JW, Beirne OR: Lingual ﬂap retraction and prevention34. Fielding AF, Rachieze DP, Frazier G: Lingual nerve paresthesia of lingual nerve damage associated with third molar surgery: A following third molar surgery: A retrospective clinical study. systematic review of the literature. Oral Surg Oral Med Oral Oral Surg Oral Med Oral Pathol 84:345, 1997 Pathol Oral Radiol Endod 91:395, 200135. Alling CC: Dysesthesia of the lingual and inferior alveolar 54. Gargallo-Albiol J, Buenechea-Imaz R, Gay-Escoda C: Lingual nerves following third molar surgery. J Oral Maxillofac Surg nerve protection during surgical removal of lower third molars. 44:454, 1986 a prospective randomised study. Int J Oral Maxillofac Surg36. Robert RC, Pogrel MA: Nerve damage and lower third molars. 29:268, 2000 J Oral Maxillofac Surg 61:54, 2003 (suppl 1) 55. Chossegros C, Guyot L, Cheynet F, et al: Is lingual nerve37. Moss CE, Wake MJ: Lingual access for third molar surgery: A protection necessary for lower third molar germectomy? A 20-year retrospective audit. Br J Oral Maxillofac Surg 37:255, prospective study of 300 procedures. Int J Oral Maxillofac Surg 1999 31:620, 2002