Advances in Extraction Techniques

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TechnologicalA d v a n c e s i n E x t r a c t i o n

Techniques andO u t p a t i e n t O r a lS u r g e r y

Adam Weiss, DDS*, Avichai Stern, DDS, Harry Dym, DDS

There have been several exciting technological advances in extraction techniques and

outpatient oral surgery within the last decade. A variety of new instruments and tech-

niques are revolutionizing the fields of oral and maxillofacial surgery and dentistry.

A powered periotome has been developed to atraumatically extract teeth. This instru-ment is particularly useful for immediate or delayed implant placement. In addition,

a technique using implant drills has been developed to extract teeth in preparation for

immediate implant placement. Piezosurgery is also being increasingly used for outpa-

tient oral surgery techniques. The precise and effortless nature of piezosurgery has

been used in the removal of certain third molars and in bone grafting. Moreover, the

Physics Forceps has been created, which uses class 1 lever mechanics to extract teeth

without having to use excessive force or squeezing motion. Lasers are also being used

for a wide variety of outpatient procedures such as removal of impacted teeth and exci-

sion of oral lesions. Orthodontic techniques are also being used by some practitioners to

help facilitate extraction of impacted teeth near the inferior alveolar nerve. The use of

polyurethane foam to help close oral antral communications may offer a simple tech-

nique of handling this fairly common occurrence following dental extractions.

POWERED PERIOTOME

The traditional means of extracting teeth often involving creation of a mucoperiosteal

flap, elevation, and luxation with forceps often results in fracture or deformation of the

dentoalveolar complex.1 This trauma could lead to ridge defects, making the

Department of Dentistry and Oral and Maxillofacial Surgery, The Brooklyn Hospital Center,121 Dekalb Avenue, Brooklyn, NY 11201, USA* Corresponding author.E-mail address: [email protected]

KEYWORDS

Powered periotome Polyurethane foam Piezosurgery Immediate implants Orthodontic extrusion Bone grafting Physics forceps

Dent Clin N Am 55 (2011) 501513doi:10.1016/j.cden.2011.02.008 dental.theclinics.com0011-8532/11/$ see front matter 2011 Elsevier Inc. All rights reserved.
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placement of implants very difficult or even impossible in some cases. Also, elevation

of the mucoperiosteum may compromise the periosteal blood supply to the alveolus,

leading to loss of marginal alveolar bone even in relatively atraumatic extractions. In

addition, if the adjacent teeth to the tooth to be extracted have extensive restorations

or crown coverage, the powered periotome eliminates the need to elevate against and

possibly damage these restorations.

A powered periotome (Powertome 100S, WestPort Medical, Salem, OR) as

shown in Fig. 1 has been developed that allows for the precise extraction of

a tooth while producing minimal or no alveolar bone loss. This atraumatic means

of dental extraction preserves bone and gingival architecture and gives the clini-

cian the option of placing future or even immediate implants. The powered perio-

tome functions by using the mechanisms of wedging and severing to aid in

tooth extraction.2 As shown in Fig. 2, these instruments are made of very thin

metal blades that are gently wedged down the periodontal ligament space in

a circumferential manner. This device severs Sharpeys fibers, which function to

secure the tooth within the alveolar socket. After most of the Sharpey fibers

have been severed from the root surface, gentle rotational movement with minimal

lateral pressure will facilitate tooth removal.

A powered periotome is an electric unit that contains a handpiece with a periotome

that is activated by a foot control. This device allows precise control over the quantity

of force that the periotome tip exerts and the distance it travels into the periodontal

ligament space. The instrument has a microprocessor-run actuator that eliminates

uncertainty while extracting a tooth. As shown in Fig. 1, this device comes with

a controller box that can be adjusted to 10 different power settings. In addition, the

use of the Powertome 100S system frequently allows flapless removal of teeth,decreasing postoperative pain and discomfort while maintaining the periosteal blood

supply to the alveolus.3 The automated powered periotome system also reduces

concern for fracture of lingual bone or buccal plate during difficult extractions. The

use of a standard periotome is a much more tedious process and can actually cause

unneeded discomfort for the patient, especially if a mallet is also needed to separate

the tooth from bone.

When using the powered periotome, the authors have found that starting interprox-

imally seems to work most efficiently because of the thickness of the interproximal

bone. It is important to keep the blade parallel along the long axis of the tooth being

removed. The blade should follow the tooth anatomy circumferentially in an apicaldirection in 2- to 3-mm increments. When extracting a multirooted tooth, the authors

have found it most efficient to section the tooth and treat each sectioned root as a

single-rooted tooth.4 This instrument has a very small learning curve, and has been

Fig. 1. Powered periotome.

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used by both general practice and oral surgery residents for tooth extractions. Photo-

graphs from a clinical case taken in the authors clinic are shown in Figs. 3 to 6.

Clinical use by investigators5 has shown that this product works efficiently to deliver

an intact extraction socket with excellent patient acceptance, while at the same time

adding little to no additional time as compared with other surgical extraction tech-

niques. Regardless of whether an implant is placed immediately after extraction or if

the socket is grafted in preparation for future implant placement, the preservation of

alveolar bone allows for more esthetic and functional implant restorations. Millimeters

do count when it comes to implants.

USING IMPLANT DRILLS FOR EXTRACTIONS PRIOR TO IMMEDIATE

IMPLANT PLACEMENT

The placement of implants for the restoration of lost dentition is becoming common-

place as a treatment option. Immediate implants are in high demand, due to the rising

requests for prompt restoration. As mentioned earlier, the key to placing successful

and long-lasting immediate implants is preserving as much bone as possible by

extracting the tooth as atraumatically as possible. Yalcin and colleagues6 presented

a novel, minimally invasive technique to aid in the extraction of the tooth. To avoid

traumatizing the surrounding bone during elevation, implant drills were placed in the

root canals to thin the root walls giving way to extraction with the application of

much less force, thereby decreasing the chance of traumatizing the thin buccal

bone. The thinning of the walls of the roots prior to elevation made it easier to remove

Fig. 2. Powered periotome instrument.

Fig. 3. Preoperative photograph.

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the teeth and minimized the risk of damaging the thin labial wall, especially in root frac-

tures where the fracture line was deep in the socket in immediate implant cases. The

investigators were able to successfully complete this procedure with no incisions and

without having to reflect any flaps. There was no damage to the labial plate in all of

their presented cases. The successful use of this technique may decrease the need

for regenerative techniques that could result in graft-related or membrane-related

complications.

PIEZOSURGERY

Piezosurgery was introduced in 1988 and has been improved upon since then. Piezo-

surgery is an innovative bone surgery technique that produces a modulated ultrasonic

frequency of 24 to 29 kHz, and a microvibration amplitude between 60 and 200 mm/s.7

The amplitude of the vibrations created allows a very clean and precise surgical cut.

Piezosurgery is very effective in the creation of osteotomies because it works

Fig. 4. Intraoperative photograph.

Fig. 5. Intraoperative photograph.

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selectively, without harming soft tissues such as nerves and blood vessels even with

accidental contact with the cutting tip.8 Piezosurgery thus has a tremendous advan-

tage over the use of burrs and surgical saws that have the potential to cause destruc-

tion to soft tissue. When compared with oscillating microsaws, the oscillation of the

piezosurgery scalpel tip is very small and therefore able to perform more precise

and safe ostetomies.9 Traditional burrs and microsaws do not distinguish hard andsoft tissue.10 Piezosurgery also gives the operator a clearer field of vision by producing

a very restricted bloody region. In addition, as shown in Figs. 7 and 8, the surgical

control of the device is effortless compared with rotational burrs or oscillating saws

because there is no need for an additional force to oppose rotation or oscillation of

the instrument11

In a recent study by Sortino and colleagues,7 rotary and piezoelectric techniques

were compared in terms of postoperative outcome. The average time of surgery

Fig. 6. Postoperative photograph.

Fig. 7. Piezosurgery used to extract impacted wisdom tooth.



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was 25.83% higher with the piezoelectric technique in comparison with the rotary

technique. Despite the longer time of the procedure, the investigators also noted

that the piezoelectric osteotomy reduced postoperative facial swelling and trismus.

The ability of piezosurgery to allow precise and selective cuts makes this a useful

technique when performing surgery close to the inferior alveolar neurovascular bundle

and/or the roots of adjacent teeth. The removal of the body of the mandible lateral

cortical bone with piezoelectric instrumentation allows adequate access to the

surgical area, excellent visibility, minimal bone loss, and precise cutting ability, and

allows the protection of the inferior alveolar nerve (IAN) by sparing the soft tissue

when osteotomy is performed blind.12 Because the bone-cutting ability is so precise

with minimal bone loss, investigators using this technique have found it easy to

readapt the bone windows to their former location and fixate them. 11Similarly, piezo-

surgery can be used to perform sinus lifts in a very precise and controlled manner, as

shown in Figs. 9 and 10.

By contrast, manual and/or mechanical instruments used in the close proximity of

delicate structures (vascular, nervous tissue) do not allow for control of the cutting

depth and can damage these structures by accidental contact.7 This new bone lid

technique described uses the piezosurgery device to cut and elevate a precisely

defined bone lid on the lateral cortex of the mandible to provide access to the teeth

needing extraction or even a lesion that needs to be excised. The bone window is

then elevated with the help of a curved osteotome. The tooth or lesion can then be

Fig. 8. Piezosurgery used to extract impacted wisdom tooth.

Fig. 9. Piezosurgery used for sinus lift procedure.

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seen and subsequently removed atraumatically by either sectioning with piezosurgery

or by circular piezo-osteotomy. After the visual confirmation of an undamaged IAN and

adjacent tissues, the bone lid is placed back into its original position and fixated with

absorbable miniplates.

Bone-Grafting Technique Distal to Second Molar After Third Molar Exo-Piezosurgery

Besides being a useful in exodontias and lesion excision, piezosurgery is now being

used in bone grafting. A periodontal pocket distal to the second molar often leads

to increased dental sensitivity, increased difficulty in attaining proper oral hygiene in

the zone, and the gradual loss of bone support distal to the second molar.13 Kugelberg

and colleagues14

studied 215 cases and found that 2 years after third molar removal,43.3% of the patients had probe depths of greater than 7 mm distal to the adjacent

second molar.

Penarrocha and colleagues15 presented a technique in which a bone block is har-

vested from the retromolar zone distal to the defect using a piezosurgery instrument

along with abundant sterile physiologic saline irrigation. The bone block is then placed

strategically distal to the second molar, in the area of the defect. After stable graft

placement within the walls of the defect is confirmed, 3-0 silk sutures are then placed.

The investigators noted that the bone block prevented soft tissue collapse, and no

membrane was required in this procedure.

USE OF PHYSICS FORCEPS FOR TOOTH EXTRACTION

The Physics Forceps16 (Fig. 11) uses first-class level mechanics to atraumatically

extract a tooth from its socket. One handle of the device is connected to a bumper,

which acts as a fulcrum during the extraction. This bumper is usually placed on the

facial aspect of the dental alveolus, typically at the mucogingival junction. The beak of

the extractor is positioned most often on the lingual or palatal root of the tooth and into

the gingival sulcus.17 Unlike conventional forceps, only one point of contact is made

on the tooth being extracted. Together the beak and bumper design acts as a simple

first-class lever. A squeezing motion should not used with these forceps. By contrast,the handles are actually rotated as one unit using a steady yet gentle rotational force

with wrist movement only. Once the tooth is loosened, it may be removed with tradi-

tional instruments such as a conventional forceps or rongeur. If considering immediate

implant placement, the clinician should consider reducing the buccal aspect of the

tooth to be extracted a couple of millimeters with a surgical bur subgingivally, or

consider using a periotome before using the Physics Forceps.

Fig. 10. Piezosurgery used for sinus lift procedure.



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LASERS FOR EXTRACTION OF IMPACTED TEETH

The use of lasers in outpatient oral and maxillofacial surgeries is becoming more and

more popular. Lasers provide a useful alterative and/or adjunct to traditional tech-

niques. The laser osteotomy for removal of impacted teeth offers noncontact and

low-vibration bone cutting to allow precise bone ablation without any visible, negative,

thermal side effects.18 Stubinger and colleagues18 presented a comparison of tech-

niques using Er:YAG lasers, using either a fiber-optic delivery system or an articulated

arm delivery system to remove impacted teeth in 30 patients. In 20% of the cases in

which the articulated arm delivery laser was used to section teeth, a conventional

dental drill was needed to finish the procedure. For the surgical extraction of the teeth,

the covering bone was first ablated, layer by layer, using the Er:YAG laser. In the case

of the fiber-optic Er:YAG laser the fiber was closely guided around the teeth, creating

a narrow gap with minimal bone loss. After uncovering the teeth, they were extracted

conventionally by means of standard forceps. However, 4 impacted teeth required

separation using the laser, taking care not to damage the adjacent soft tissue, which

was protected by elevators. Despite the encouraging clinical results, Er:YAG laser

osteotomies tend to be time consuming, and some patients complained about the

sound and smell of the laser surgical procedure. Another disadvantage of the laserapplication was insufficient operative suction, which significantly inhibited the laser

cutting because of the overall volume of irrigation and blood covering the bone

surface. Another disadvantage of both systems was the lack of a feedback system

for depth control. As a result, the technique involves a learning curve, and ultimate

success may be dependent on the experience of the surgeon.

LASERS FOR BIOPSY AND TREATMENT OF ORAL LESIONS

Many oral and maxillofacial surgeons are now using laser therapy for a variety of

outpatient surgical procedures. As an example, the physical properties of the laserand its effect on tissue make it ideal for incisional or excisional removal of intraoral

pathologic lesions. Laser therapy provides for excellent hemostasis and has a low

propensity for postoperative scarring.19 Ben-Bassat and colleagues20 first described

laser therapy for the treatment of oral leukoplakia in 1978. Since then, several studies

have found it to be a safe and effective treatment option. Many different laser types

have been used in the treatment of oral leukoplakias, including the carbon dioxide

Fig. 11. Physics Forceps.

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(CO2), neodymium:yttrium-aluminum garnet (Nd:YAG), argon, and potassium-

titanylphosphate (KTP) lasers.21 In a large retrospective study, van der Hem and

colleagues22 used the CO2 laser to treat 282 leukoplakias in 200 patients and achieved

a cure rate of 89% during a mean follow-up period of 52 months. The benefits of laser

therapy include the creation of a bloodless surgical field and thus improved visualiza-

tion during surgery, decreased postoperative pain, and limited scarring and

contraction.23 The disadvantages of laser treatment include the inability to obtain

samples for histologic analysis when ablative techniques are used, and the need for

additional time-consuming safety measures during surgical treatment.

NEW TECHNIQUE TO DECREASE PARESTHESIA RISK WITH EXTRACTION OF IMPACTED

THIRD MOLARS (HORIZONTALLY OR MESIALLY IMPACTED THIRD MOLARS)

The risk of paresthesia is one of the most feared complications when removing third

molars that have radiographic signs of proximity to the IAN. If there is close proximity

between the IAN and the roots of the third molar, the incidence of paresthesia may beas high as19%.24 Landi and colleagues25 present a current case series demonstrating

a technique that surgically removed the mesial aspect of the anatomic crown of the

third molar (M3) to create enough space for mesial M3 migration. After the migration

of the M3 had occurred; the extraction could then be performed in a second surgical

procedure while minimizing neurologic risks. The investigators noted that all M3s

moved mesially within 6 months (mean 174.1 days, range 92354 days) and could

be successfully removed without any neurologic consequences. The goal of this tech-

nique was to allow spontaneous mesial migration of the impacted M3 by sectioning

the portion of the M3 crown in contact with the distal aspect of the second molar.

Three to 4 months after the surgery, all M3s moved forward and reached the distalaspect of the second molars. It is important to keep in mind that every effort should

be made, at least during the first operative procedure, to not to interfere with tooth

vitality. In the worst-case scenario, a pulpotomy procedure can be done and the

procedure can continue as planned.

ORTHODONTIC TECHNIQUE: EXTRACTION OF IMPACTED MANDIBULAR

THIRD MOLARS

The use of orthodontics in a multidisciplinary approach to perform safe tooth extrac-

tion is another advancement worthy of discussion. Third molars in close proximity tothe IAN have a significantnegative impact on recovery for pain and oral function.26

Bonetti and colleagues27 described an orthodontic-surgical procedure that has

proven useful for safe extraction of impacted third molars in the presence of high risks

(such as neurologic complications) resulting from the tooths close location to the

mandibular canal. This technique involved assessment of surgical risks, creation of

the orthodontic anchorage, surgical exposure of the third molar crown, orthodontic

extrusion of the third molar as shown in (Fig. 12), clinical and radiographic assessment

of the extrusion level, and finally third molar extraction. The advantage of this tech-

nique is that the risk of direct trauma to the nerve is eliminated, due to both the

increased distance between the roots and the mandibular canal and the decreasedneed for surgical manipulation during the extraction. A potential problem with this

technique is soft tissue damage from impingement on the mucosa of the cheek and

the gingiva. This type of damage is often unavoidable because of the location of the

orthodontic device. In addition, working in this area of the mouth presents great diffi-

culty, and the action of the masseter muscle leads to cheek compression against the

orthodontic appliances. Often this procedure is also more time consuming than simple



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extraction techniques. Each clinical case should be judged individually. For example,

this technique will be of no value for a tooth that cannot move because of ankylosis.

This technique should be used only in carefully selected cases in conjunction with anorthodontist, being certainly difficult, time consuming, and not always successful.

CLOSURE OF ORAL ANTRAL COMMUNICATIONS WITH POLYURETHANE FOAM

Oral antral communications (OACs) are a commonly seen clinical complication treated

by oral and maxillofacial surgeons. If less than 5 mm, these communications will often

close spontaneously,28 though the actual size of an OAC is often difficult to determine

clinically. Frequently these defects are surgically closed using multiple varied tech-

niques to avoid the development of chronic sinusitis and the development of a fistula.29

A variety of soft tissue flaps such as the buccal sliding flap and the rotational palatal

Fig. 12. Orthodontic bracketing to facilitate third molar removal.

Fig. 13. Closure of oral antral communication with polyurethane foam.

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flap have been presented in the literature as a means of closing OACs. Visscher and

colleagues30 presented a new and easy to perform method of closing OACs with use

of a biodegradable polyurethane foam, without the need for surgical flap rotations. It is

believed that the polyurethane foam provides reinforcement for the blood clot and

protects it from being displaced. Ten consecutive patients with OACs were treated

with this foam (as shown in Fig. 13) and evaluated at 2 weeks and 8 weeks after

closure. In this feasibility study, 7 of the 10 patients achieved closure without further

surgical intervention. This technique allows the closure of OACs without any

other additional training or special equipment. Although more studies on this tech-

nique will need to be performed, this procedure possibly provides a valuable alterna-

tive to surgical closure OACs.

DISCUSSION

Outpatient oral and maxillofacial surgical techniques have come a long way in recentyears. A variety of new instruments and techniques are enabling surgeons to provide

services to patients in a shorter period of time with higher accuracy. The powered peri-

otome functions by aiding the surgeon in atraumatically extracting teeth, which allows

for either immediate or delayed implant placement into a preserved socket. A tech-

nique using implant drills has also been developed to extract teeth in preparation

for possible immediate implant placement. Piezosurgery is also being used, as

many surgeons are taking advantage of its precise and effortless nature. This type

of surgery provides the patient with safe and accurate procedure because soft tissue

remains unharmed. Also, the Physics Forceps has been invented, which allows its

operator to remove teeth without the use of excessive force or squeezing motion.Lasers are now being used for extraction of impacted teeth and excision of oral

lesions. Orthodontic techniques are also being introduced to help minimize nerve

damage when a tooth that is near the IAN needs to be extracted. The use of polyure-

thane foam to help close OACs remains a new possible treatment alternative to more

complicated treatment that is possibly just as effective. Technology has allowed

extraction techniques and outpatient oral and maxillofacial surgery to evolve, and

both surgeons and patients are benefiting.

REFERENCES

1. Dym H, Ogle O. Atlas of minor oral surgery. Philadelphia: W.B. Saunders

Company; 2001.

2. White J, Holtzclaw D, Toscano N. Powertome assisted atraumatic tooth extrac-

tion. J Implant Advanced Clin Dent 2009;1:6.

3. Levitt D. Atraumatic extraction and root retrieval using the Periotome: a precursor

to immediate placement of dental implants. Dent Today 2001;20(11):537.

4. Misch CE, Perez H. Atraumatic extractions: a biologic rationale. Dent Today 2008;

27(8):1001.

5. Kang J, Dym H, Stern A. Use of the Powertome Periotome to preserve alveolar

bone during tooth extractiona preliminary study. Oral Surg Oral Med OralPathol Oral Radiol Endod 2009;108:4.

6. Yalcin S, Aktas I, Emes Y, et al. A technique for atraumatic extraction of teeth

before immediate implant placement. Implant Dent 2009;18:6.

7. Sortino F, Pedulla E, Masoli V. The piezoelectric and rotatory osteotomy technique

in impacted third molar surgery: comparison of postoperative recovery. J Oral

Maxillofac Surg 2008;66:24448.



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8. Kotrikova B, Wirtz R, Krempien R, et al. Piezosurgerya new safe technique in

cranial osteoplasty? Int J Oral Maxillofac Surg 2006;35:4615.

9. Stubinger S, Kuttenberger J, Filippi A, et al. Intraoral piezosurgery: preliminary

results of a new technique. J Oral Maxillofac Surg 2005;63:12837.

10. Grenga V, Bovi M. Piezoelectric surgery for exposure of palatally impacted

canines. J Clin Orthod 2004;38:4468.

11. Eggers G, Klein J, Blank J, et al. Piezosurgery: an ultrasound device for cutting

bone and its use and limitations in maxillofacial surgery. Br J Oral Maxillofac

Surg 2004;42:4513.

12. Degerliyurt K, Akar V, Denizci S, et al. Bone lid technique with piezosurgery to

preserve inferior alveolar nerve. Oral Surg Oral Med Oral Pathol Oral Radiol

Endod 2009;108:e15.

13. Motamedi MH. A technique to manage gingival complications of third molar

surgery. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:140.

14. Kugelberg CF, Ahlstrom U, Hugoson A, et al. The influence of anatomical, path-

ophysiological and other factors on periodontal healing after impacted lower third

molar surgery. J Clin Periodontol 1991;18:37.

15. Penarrocha M, Gomez D, Garcia B, et al. Treatment of bone defects produced by

lower molar extraction using ultrasound-harvested autologous bone grafts. J Oral


16. Golden RM. Dental plier design with offsetting jaw and pad elements for assisting

in removing upper and lower teeth utilizing the dental plier design. US patent

6,910,890. GoldenMisch Inc; 2005.

17. Misch C, Perez H. Atraumatic extractions: a biomechanical route. Dent Today

2008;27:8.18. Stubinger S, von Rechenberg V, Zeilhofer HF, et al. Er:YAG laser osteotomy for

removal of impacted teeth: clinical comparison of two techniques. Lasers Surg

Med 2007;39:5838.

19. Strauss RA. Lasers in oral and maxillofacial surgery. Dent Clin North Am 2000;

44(4):85173.

20. Ben-Bassat M, Kaplan I, Shindel Y, et al. The CO2laser in surgery of the tongue.

Br J Plast Surg 1978;31:155.

21. Ishii J, Fujita K, Komori T. Laser surgery as a treatment for oral leukoplakia. Oral

Oncol 2003;39:759.

22. van der Hem PS, Nauta JM, van der Wal JE, et al. The results of CO2laser surgeryin patients with oral leukoplakia: a 25 year follow up. Oral Oncol 2005;41:31.

23. Meltzer C. Surgical management of oral and mucosal dysplasias: the case for

laser excision. J Oral Maxillofac Surg 2007;65:293.

24. Renton T, Hankins M, Sproate C, et al. A randomized controlled clinical trial to

compare the incidence of injury to the inferior alveolar nerve as a result of coronec-

tomy and removal of mandibular third molar. Br J Oral Maxillofac Surg 2005;43:7.

25. Landi L, Manicone P, Piccinelli S, et al. Novel surgical approach to impacted

mandibular third molars to reduce the risk of paresthesia: a case series. J Oral


26. White RP. Recovery after third-molar surgery. Am J Orthod Dentofacial Orthop2004;126:289.

27. Bonetti GA, Bendandi M, Laino L, et al. Orthodontic extraction: riskless extraction

of impacted lower third molars close to the mandibular canal. J Oral Maxillofac

Surg 2007;65:25806.

28. von Wowern N. Correlation between the development of an orantral fistula and

the size of the corresponding bony defect. J Oral Surg 1973;31:98.

Weiss et al512


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29. von Wowern N. Frequency of oro-antral fistulae after perforation to the maxillary

sinus. Scand J Dent Res 1970;78:394.

30. Visscher S, van Minnen B, Rudolf RM. Closure of oroantral communications using

biodegradable polyurethane foam: a feasibility study. J Oral Maxillofac Surg

2010;68:2816.


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