OOOOE314 September 2010

Conclusions: The data evaluated in this study demonstratedthat CASS can be used to effectively normalize overjet andachieve class I occlusion.

DISTRACTION OSTEOGENESIS FOR PRIMARY RECON-STRUCTIVE TREATMENT OF AN AVULSIVE GUN SHOTWOUND TO THE MANDIBLE Authors: Marianela Gonza-lez, DDS, MS, MD; Cesar A. Guerrero, DDS; Michael J.Ellis, DDS; Michael P. Ding, DDS, MD

Introduction: Low caliber gunshot wounds (GSW) to themaxillofacial region are often seen in Level I trauma centers. Theclinical application of bone transport has been reported since1995, and since then we have considered its use for extensivemandibular discontinuity defects without the need of externaldevices.

Purpose: To create complete reconstruction of extensivemandibular defects in an open infected wound with minimalcomplications; from bone and soft tissue formation, to implantand crown placement. 1) Facial Harmony, 2) Function, 3) Sta-bility, 4) Low Morbidity, 5) Ideal Dental Rehabilitation, 6) Reg-ular Activities

Materials and Methods: 13 patients (ages 20-27 years) weretreated by Intraoral Bone Transport after sustaining low-calibergunshot wounds to the mandible. The purpose of the BoneTransport technique is to create bone and soft tissues that fill upa defect. By continuously moving a disc of bone across a conti-nuity defect, new bone is formed behind the transporting seg-ment. This segment is moved until it docks with the receivinghost bone. Cephalometric and panoramic radiographs, along withstereolythography, are used for surgical planning and prediction.Stereolythography in particular is very useful for obtaining theanatomical model of the defect to be restored, along with theexact measurements for pre-bending of the reconstruction plate,the devices, the distraction vector and location of the screws priorto surgery. Activation is 1mm per day until the planned move-ment is achieved. The consolidation period is based on previoushistological research studies. For each centimeter of distraction,60 days of consolidation is required. After the consolidationperiod has elapsed, dental implants may be placed for prostheticreconstruction.

Results: Extensive mandibular defects were successfully re-constructed in all patients using the Intraoral Bone TransportTechnique. Distraction gaps were filled with new bone and softtissues that were adequate in architecture for osseointegratedimplants. Additional surgery is required to complete tissue heal-ing at the docking site. No infection was observed during or aftertreatment Conclusions: Intraoral bone transport is an ideal ap-proach to reconstruct contaminated mandibular defects after gun-shot injuries. BMP-2 can be used to accelerate bone formationand consolidation at both the distraction site and at the dockingsite. Bone grafts in gunshot injuries have a higher morbidity, andless of a chance for normal tissue architecture for implant place-ment Advantages and goals of the s technique are excellentbiological response, feasibility for implant placement, completefunctional and esthetic rehabilitation, and no need for extraoralappliances.

IDIOPATHIC CONDYLAR RESORPTION: ANALYSIS OFTREATMENT OUTCOMES USING CUSTOM-MADE TMJTOTAL JOINT PROSTHESES Author: Mohammed Nader-

shahh, BDS; Pushkar Mehra, BDS, DMD

Purpose: Idiopathic condylar resorption (ICR) presents adiagnostic and therapeutic challenge to practitioners because ofits rarity of occurrence, progressive nature of the deformity, andits simultaneous involvement of skeletal, occlusal and articularstructures. Traditionally, costochondral grafts have been used forTMJ replacement in this sub-group of patients, but availability ofpatientfitted TMJ alloplastic replacement systems offers manybenefits over autogenous replacement options.

Methods: A retrospective analysis of all patients who under-went surgical treatment of ICR by a single surgeon between 2000and 2008 was performed. Criteria for inclusion included: 1)Mandibular retrusion secondary to TMJ resorption, 2) Negativescreening for known forms of systemic arthrides, 3) Absence ofhistory of trauma, 4) Presence of anterior open bite with Class IImalocclusion, and 5) Bilateral TMJ total joint replacement andconcomitant mandibular advancement. Examinations were per-formed presurgically (T1), immediately postsurgery (T2) and atlongest follow-up (T3). Visual analog scales were used for sub-jective examination of jaw function, dietary restrictions, func-tional disability, patient satisfaction and pain. Objective exami-nations assessed TMJ sounds, anterior open bite, occlusalrelationships, mandibular range of motion, nerve injury and scar-ring. Superimposition of cephalometric tracings was done toevaluate surgical change (T2-T1) and relapse (T3-T2).

Results: 14 patients were included in the study. Averagepatient age was 25.6 years (range 22 – 32) and average follow-upwas 3.4 years (R 2-8). All patients were female and gave a historyof TMJ clicking at some stage during their lifetime. 10/14 (70%)patients correlated the period of active orthodontic treatment tothe initiation of resorption. Average surgical time was 8.5 hrs (R5.5-12) and the average hospitalization was 3.6 postsurgical days(R 3-7). Average mandibular advancement at Point B was 18.7mm (R 14-27) and average occlusal plane change was -5.8degrees (R 3-8). 64% patients underwent maxillary orthognathicsurgery for posterior downgrafting with rigid fixation and graft-ing.

Pain(0-10)

TMJSounds(# pts)

Anterioropenbite

(# pts)

Maximalinterincisal

openingwithout

pain (mm)

Maximalinterincisal

openingirrespective

of pain(mm)

Lateralexcursion Diet

Permanentcranialnerveinjury

Objectionablescarring

Preop(T1)

5.6(0-10)

14 14 18.6(5-39)

44(37-52)

8.9(3-9)

6.8(0-10)

0 0

Postop(T3)

2 0 38.8(30-45)

39.5(35-45)

1.6(0-3)

2.3(0-4)

0* 0

*One patient had prolonged weakness of the frontal/temporal branch,which resolved completely in 7 months.

Conclusions: ICR patients can be treated very effectivelyusing custom-made TMJ total joint prostheses for correction ofTMJ resorption and mandibular advancement in combinationwith maxillary orthognathic surgery, when indicated, for correc-tion of the associated dentofacial deformity. Use of these pros-theses eliminates donor site morbidity and allows for extremelylarge mandibular advancements to be performed in a predictablemanner with excellent stability of orthognathic movements.

REFERENCES:1. Arnett G.W., Milam S.B., Gottesman L. Progressive mandibular

retrusion: part I—idiopathic condylar resorption. Am J Orthod

Dentofacial Orthop. 1996;110:8-15.

2. Wolford L.M., Cardenas L. Idiopathic condylar resorption; diag-