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DEPT OF ORTHODONTICS& DENTOFACIAL ORTHOPAEDICSPEOPLES DENTAL ACADEMY

BHOPAL(M.P)

Surgical Procedures for the Treatment of

OSA Kok Weng Lye and Joseph R. Deatherage

Seminars in Orthodontics, Vol 15, No 2 (June), 2009: pp 94-98.

PRESENTED BY DR BHAGWAT R.

KAPSE PG II year STUDENT

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Apnea” is the Greek word for “without breath.”

Obstructive sleep apnea (OSA) was( 1837) First Charles Dickens term

“Pickwickian syndrome” described a similar presentation of a

typical OSA patient; obese, somnolent, and with an excessive appetite.

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In 1956 Sidney Burwell documented a case of an OSA patient,

rationalized the signs and symptoms, and made a distinction between this

disease and other illnesses. The prevalence of the disease has been found

to be 8% in men and 2% of women (United States).

Carlson JT, Hedner JA, Ejnell H, et al: High prevalence of hypertension in sleep apnea patients independent of obesity. Am J Respir Crit Care Med 150:72-77, 1994

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This chronic condition has wide ranging effects,from health problems to serious social and financial consequences.

The collapse and blockage of the airway leads to 1. Snoring, 2. Multiple arousals,3. Sleep fragmentation,4. Hypoxia, and5. Reperfusion injuries.

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Snoring

The snoring is a result of the vibration of the tissues of the posterior airway caused by the narrowing of the airway and air turbulence.

Thus reduced air flow causes hypoxia and hypercapnia which lead to arousals and sleep fragmentation.

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This chain of events results in excessive daytime sleepiness (EDS) in 90% of OSA patients.

In turn, EDS affects concentration, cognition, and ability to work effectively and may lead to traffic accidents.

Young T, Blustein J, Finn L, et al: Sleep-disordered breathing and motor vehicle accidents in a population based sample of employed adults. Sleep 20:608-613, 1997

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Physiologically, OSA may bring about- Arrhythmias, Heart failure, Ischemic heart disease, Systemic and pulmonary hypertension, Neurological complications reperfusion .

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In fact, it is a potential life-threatening problem.-

If left untreated, has a mortality rate of 37% in moderate-to-severe OSA during a period of 8 years.

He J, Kryger MH, Zorick FJ, et al: Mortality and apnea index in obstructive sleep apnea: Experience in 385 male patients. Chest 94:9-14, 1988

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Diagnosis of OSA

It is made from a detailed physiological examination during sleep called polysomnography.

This is the required objective investigation for the confirmation of the presence and severity of the condition.

It is also able to pickup other sleep disorders like narcolepsy, periodic limb movement disorder and central sleep apnea.

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The various parameters calculate the amount of apneas

1. Cessation of air flow for more than 10 s2. Hypopnea i.e decrease in air flow by 50%

with significant oxygen desaturation3. Quality of sleep i.e amount of REM, stage 3

and stage 4 sleep.

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Including an accurate medical history, physical examination, airway analysis, and other additional aids to identify the sites of obstruction in the airway.

Some medical conditions, i.e chronic obstructive pulmonary disease, muscular dystrophy, cardiac dysfunction, hypothyroidism, and pituitary tumors.

Davila DG: Medical considerations in surgery for sleep apnea, In Waite PD (ed). Oral and Maxillofacial Treatment of Obstructive Sleep Apnea. Oral Maxillofac Surg Clin North Am 7:205-219, 1995

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Physical examinationWeight and body mass index . A neck circumference > 43.2 cm is also a

positive risk factor for OSA.

MathurR,DouglasNJ:Familystudiesinpatientswiththe sleep apnea-hypopnea syndrome. Ann Intern Med 122: 174-178, 1995

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Clinical examination Any nasal septal deviation, internal or

external valve collapse, turbinate hypertrophy, nasal polyps, chronic sinusitis,

which leads to increased negative inspiratory pressure and bring about collapse in the posterior airway.

Lavie P, Fischel N, Zomer J, et al: The effects of partial and complete mechanical occlusion of the nasal passages on sleep structure and breathing in sleep. Acta Otolaryngol 95:161-166, 1983

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Clinical examination

nasopharynx, oral pharynx, and hypopharynx are examined with the aid of a flexible endoscope.

The presence and size of any adenoid hypertrophy in the nasopharynx may be of significance and is noted.

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The focus of interest is in the retropalatal and retroglossal openings.

It is examined during normal breathing. Its shape and any constrictions in the anteroposterior or lateral dimensions are noted.

Muller’s maneuver is also performed to to correlate to the OSA severity.

Terris DJ, Hanasono MM, Liu YC: Reliability of the Muller maneuver and its association with sleep-disordered breathing. Laryngoscope 110:1819-1823, 2000

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Muller’s maneuver

• In this maneuver, the patient attempts to inhale with his mouth closed and his nostrils plugged, which leads to a collapse of the airway.

• Introducing a flexible fiberoptic scope into the hypopharynx to obtain a view, the examiner may witness the collapse and identify weakened sections of the airway.

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Flexible fiberoptic scope

A positive test results means the site of upper airway obstruction is likely below the level of the soft palate, and the patient will probably not benefit from a UPPP alone.

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The retroglossal opening is the airway at the tongue base level.

The dimension at this level is ascertained to judge the contribution of any macroglossia or retro positioning of the tongue and mandible towards the OSA.

Kuna ST, Bedi DG, Ryckman C: Effect of nasal airway positive pressure on upper airway size and configuration. Am Rev Respir Dis 138:969-975, 1988

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• Presence of enlarged lingual tonsils is also a contributory factor .

• The hypopharynx is checked for any restrictions secondary to growths, laryngeal changes and vocal cords abnormalities.

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Oral examination

Should focus on Length of the soft palate, Size of the palatine tonsils, Width of the palatal vault and dental arches.

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• The Mallampati scale is used to evaluate the oropharyngeal soft tissues and the potential for airway obstruction.

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• Mallampati Scoring:• Class I: Soft palate,

uvula, fauces, pillars visible.

• Class II: Soft palate, uvula, fauces visible.

• Class III: Soft palate, base of uvula visible.

• Class IV: Only hard palate visible

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The Friedman score has been developed to assess the relationship between tongue position,tonsil size, and body mass index and the likely success of soft tissue surgical procedures.

Friedman M, Ibrahim H, Bass L: Clinical staging for sleep-disordered breathing. Otolaryngol Head Neck Surg 127:13-21, 2002

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Fujita et al categorized the upper airway obstruction as either retropalatal or retroglossal.

i. The retropalatal level involves the soft palate, uvula, and palatine tonsils.

ii. The retroglossal level involves the tongue base and supraglottic structures.

Fujita S: Obstructive sleep apnea syndrome: Pathophysiology, upper airway evaluation and surgical treatment.Ear Nose Throat J 72:67-72, 75-76, 1993

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Type I obstruction is the presence of restriction only at the retropalatal level.

TypeII obstruction is the presence of restriction only at the retroglossal level.

Type III is the presence of both obstructions at both levels.

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Moore considered the airway obstruction as a spectrum of disease,

Starting from primary snoring as the mildest form,

Upper airway resistance syndrome (UARS)And then to the different degrees of OSA; 1. mild,2. moderate, 3. severe.

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Treatment

Colin Sullivan (1981 )that Continuous positive airway pressure (CPAP) could pneumatically splint open the collapsed airway and eliminate apneas and hypopnea.

• Sullivan CE, Issa FG, Berthon-Jones M, et al: Reversal of obstructive sleep apnoea by continuous positive airway pressure applied through the nares. Lancet 1:862-865,1981

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CPAP has been the gold standard in the treatment of OSA.

There are only minimal side effects with this mode of treatment.

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However, despite its high efficacy,patients frequently cannot tolerate its usage every night for life and thus long-term acceptance has been found to below.

This has been consistent even with advancement in mask and air pressure delivery system technology.

• Richard W, Venker J, den Herder C, et al: Acceptance and long-term compliance of nCPAP in obstructive sleep apnea. Eur Arch Otorhinolaryngol 264:1081-1086, 2007

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The dental fraternity fabricated the mandibular advancement devices (MAD) for these patients as another form of non invasive therapy.

Complications associated with long term usage of the MADs,such as TMJ problems and changes in the occlusion.

Hoffstein V: Review of oral appliances for treatment of sleep-disordered breathing. Sleep Breath 11:1-22, 2007

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When the nonsurgical therapies for OSA fail or are unacceptable to the patients, surgical options are considered.

1964, Ikematsu started treating snoring with a soft palate procedure known as Uvulopalatopharyngoplasty (UPPP).

The first surgical treatment for OSA was tracheotomy in 1969 by Kuhol.

Ikematsu T: Study of snoring, forth report: Therapy. J Jpn Otorhinolaryngol 64:434-435, 1964 Kuhol W, Doll E, Franck MC: Erfolgreiche Behandlung eines pickwick syndrome Dutch eine duwertracheal kanule.

Dtsch Med Wochenschr 94:1286-1290, 1969

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The first surgical treatment for OSA was tracheotomy in 1969 by Kuhol.

Kuhol W, Doll E, Franck MC: Erfolgreiche Behandlung eines pickwick syndrome Dutch eine duwertracheal kanule. Dtsch Med Wochenschr 94:1286-1290, 1969

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Moore’s concept,

Derived from Moore’s concept, two principles of therapy.

1. First principle states that the entire upper airway is affected, especially in moderate and severe OSA.

2. The second states that the more severe the disorder, the more aggressive the surgical therapy has to be to achieve success.

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Long-Term Results of Surgery to Treat OSA

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DefiningSurgicalCure/Success

Based mainly on objective measures. In 1981,Fujita et al stated that success is

achieved if there is a 50% reduction in the postoperative apnea index.

Waite et al set their success level at a final RDI(respiratory distress index) less than 10 and no desaturations of less than 90%.

Fujita S, Conway W, Zorick F, et al: Surgical correction of anatomic abnormalities in obstructive sleep apnea syndrome: Uvulopalatopharyngoplasty. Otolaryngol Head Neck Surg 89:923-934, 1981

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• Currently, the commonly accepted definition for surgical cure is RDI or apnea-hypopnea index less than 20 with a reduction greater than 50% and few desaturations less than 90% wit improvement of subjective symptoms.

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Surgical MaxillomandibularAdvancementTechnique

Kok Weng Lye and Joseph R. Deatherag

Semin Orthod VOL 15 NO.2 JUNE 2009;15:99-104.

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Hard tissue surgery for obstructive sleep apnea (OSA) treatment includes-

1. Genioglossus advancement (GGA) 2. Maxillomandibular advancement (MMA).Troell RJ, Riley RW, Powell NB, et al: Surgical management of the hypopharyngeal airway in

sleep disordered breathing. Otolaryngol Clin North Am 31:979-1012,1998

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Genioglossus advancement surgery

initially was described as a rectangular osteotomy at the chin, which contains the genial tubercles.

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GGA has been a frequently performed procedure, but not as an isolated one, to treat OSA.

GGA often is performed together with uvulopharyngopalatoplasty, with an acceptable success rate of 80% for moderate OSA (respiratory distress index 21 to 40),

64% for moderately severe OSA (RDI 41–60), and only 15% for severe OSA (RDI 61).

• Hendler BH, Costello BJ, Silverstein K, et al: A protocol for uvulopalatopharyngoplasty, mortised genioplasty, and maxillomandibular advancement in patients with obstructive sleep apnea: an analysis of 40 cases. J Oral Maxillofac Surg 59:892-897, 2001

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Maxillomandibular advancement surgery

• Kuo et al (1979) The treatment involved the advancement of the maxilla and mandible via traditional orthognathic surgery, which was then called MMA.

• Kuo PC, West RA, Bloomquist DS, et al: The effect of osteotomy in three patients with hypersomnia sleep apnea.OralSurgOralMedOralPathol48:385

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Skeletal attachment of the suprahyoid and velopharyngeal muscles and tendons and an increase in volume of the nasopharynx, oropharynx, and hypopharynx.

Together, this advancement leads to the anterior movement of the soft palate, tongue, and anterior pharyngeal tissues

• Kuo PC, West RA, Bloomquist DS, et al: The effect of osteotomy in three patients with hypersomnia sleep apnea.OralSurgOralMedOralPathol48:385

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Subsequently, an enlargement of the posterior airway and a decrease in laxity of the pharyngeal tissues ensues and results in a decrease in the obstruction of the posterior airway space.

Since 1979,there have been several publications that showed overall success rates of 96%, 97%,98%, and 100%.

• Prinsell JR: Maxillomandibular advancement surgery in a site-specific treatment approach for obstructive sleep apnea in 50 consecutive patients. Chest 116:1519-1529,1999

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Li et al showed a 90%success rate for a group of 40 patients with a mean follow-up period exceeding 50 months.

These results are further supported by a study examining the surgical stability of MMA,

which found that the large horizontal advancement of the maxilla and mandible is stable and without significant relapse.

• Li KK, Powell NB, Riley RW, et al: Long-term results of maxillomandibular advancement surgery. Sleep Breath 4:137-140, 20009. Nimkarn Y, Miles PG,

• Waite PD: Maxillomandibular advancement surgery in obstructive sleep apnea syndrome patients: Long-term surgical stability. J Oral Maxillofac Surg 53:1414-1418, 1995

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2 Philosophies regardingthe use of MMA.

Some groups believed in a 2-stage protocol where MMA is the stage 2 procedure

if stage 1, which consists of uvulopharyngopalatoplasty,GGA, and hyoid suspension,fails.

• Bettega G, Pepin JL, Veale D, et al: Obstructive sleep apnea syndrome. Fifty-one consecutive patients treated by maxillofacial surgery. Am J Respir Crit Care Med 162:641-649, 2000

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Uvulopharyngopalatoplasty (UPPP)

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This latter protocol was developed to reduce the use and complications of the more invasive MMA procedure for patients who would have responded to the first-stage procedures.

In the landmark study from which this protocol was developed, the authors found that the success rate was 60% for stage 1 surgery and 97% for stage 2 surgery.

• Riley RW, Powell NB, Guilleminault C, et al: Obstructive sleep apnea: A review of 306 consecutive treated patients. Otolaryngol Head Neck Surg 108:117-125,1993

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For these reasons, other groups of clinicians believe in using the most efficacious technique from the start and proceeding directly with MMA.

Waiteetal,in a key study,evaluated patients who had had MMA surgery together with septoplasty and inferior turbinectomies.

• Hochban W, Conradt R, Brandenburg U, et al: Surgical maxillofacial treatment of obstructive sleep apnea. Plast Reconstr Surg 99:619-626, 1997

• Waite PD, Wooten V, Lachner J, et al: Maxillomandibular advancement surgery in 23 patients with obstructive sleep apnea syndrome. J Oral Maxillofac Surg 47:12561261, 1989

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They achieved a success rate of 96%. Based on the criteria of a 50% reduction in

the RDI and a final RDI of less than 20, Hochban et al and Prinsell also used MMA as

the primary procedure for 38 and 50 OSA patients, achieving 97% and 100% success rate, respectively.

• Hochban W, Conradt R, Brandenburg U, et al: Surgical maxillofacial treatment of obstructive sleep apnea. Plast Reconstr Surg 99:619-626, 1997

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Indications and Contraindicationsfor MMA

To be a suitable patient for MMA treatment, a few prerequisites are necessary.

The patients’ apnea-hyponea index or RDI must be greater than 15, with a lowest desaturation 90% and subjective excessive daytime sleepiness.

• Prinsell JR: Maxillomandibular advancement surgery for obstructive sleep apnea syndrome. J Am Dent Assoc 133:1489-1497, 2002

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In addition, conservative treatments, such as- weight loss, mandibular repositioning devices, continuous positive airway pressure, must

have been unsuccessful or intolerable for the patient.

The patient must also be medically fit to undergothesurgery.

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MMA should be the procedure of choice.First, there should be obstruction at multiple

sites . Second, the patient should present with a

dentofacial skeletal deformity and malocclusion, ( Class II relationship)

MMA surgery should be able to provide an opportunity to obtain multiple benefits.

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Contraindicationsfor MMA

Patients who do not meet the criteria for the MMA procedure .

who are unwilling and/or unable to undergo MMA surgery should be excluded.

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Surgical Planning and Technique

MMA is primarily orthognathic surgery in which the maxilla and mandible are advanced through osteotomies.

Surgery requires all the relevant preoperative records and planning, such as facial examination, radiographs, cephalometric analysis, nasopharyngoscopy and model surgery.

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Preoperative orthodontic treatment should be used to ensure a good postoperative occlusion as well as correcting any pre-existing malalignment of the teeth to enhance the cosmetic appearance of the patients.

Many OSA patients are older and are unwilling to undergo the recommended orthodontic phase of the treatment, or they may not wish to delay the treatment of their OSA condition.

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Some OSA patients may have multiple missing teeth, active advanced periodontal disease, or complex fixed prosthodontic restorations,

which may complicate orthodontic treatment.

The patients’ problem is often a functional one, and they may be less concerned with the esthetic improvement of Rx.

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Orthodontics

The objectives of presurgical orthodontic treatment for MMA patients is different from those of routine orthognathic surgery for patients who have dentofacial deformities.

For the MMA patients, the purpose of the presurgical orthodontic treatment is to assist in maximizing the anterior positioning of the maxilla and mandible while attempting to obtain a reasonable occlusion.

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In Class II patients, it is advisable to retract the lower incisor teeth and procline the upper incisor teeth to maximize the amount of mandibular advancement.

This step will provide the greatest amount of airway improvement.

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lateral cephalogram is a standardized and repeatable radiograph that presents the profile view of the viscerocranium.

It is a routine tool for the diagnostic workup of all OSA patients.

Cephalometric analysis helps to confirm the clinical and nasopharyngoscopy findings.

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The values of different parameters in the analysis can be compared to normal values to characterize the craniofacial relationship and the posterior airway status.

Cephalometric analysis reveals the severity of any craniofacial dysmorphy or abnormalities.

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Studies have referred to the retro-positioning of the jaws,

Short mandibular length, Long anterior face height, Clockwise rotation of the facial structure, Short cranial base, Decreased craniofacial flexure angle as common

abnormalities found in OSA patients.

• Steinberg B, Fraser B: The cranial base in obstructive sleep apnea. J Oral Maxillofac Surg 53:1150-1154,1995

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In terms of treatment planning, It is an important tool to help identify the

patients who have severe craniofacial deficiency (SNB angle75°),

They should be directly offered MMA surgery instead of soft tissue procedures. 10

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There are more advanced imaging techniques to study the posterior airway,

Cephalometric analysis still offers considerable advantages,including -

Low cost, Ease of use Minimal radiation exposure.

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Technique

The MMA is achieved by use of the standard bilateral sagittal split osteotomy technique for the mandible and the Le Fort I level maxillary osteotomy.

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The mandible is cut and a sagittal split is carried out bilaterally in the posterior body, angle and lower ramus region.

The proximal segments with the condyles are kept in the same position while the distal segment;

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The body of mandible, alveolus and teeth, are advanced according to the prefabricated occlusal splint into a Class III relationship.

The occlusal splint is made during the presurgical model surgery.

The inferior alveolar nerve is kept intact but sustains some tension during the surgical advancement procedure

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The distal segment is then fixated with bicortical screws or titanium miniplates and screws.

Performing the mandibular advancement first creates a more stable occlusal platform.

The advancement of the mandible pulls the geniohyoid, genioglossus, mylohyoid and the digastric muscles anteriorly.

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This in turn brings the base of tongue and hyoid bone forwards and upwards.

In addition, the advancement of the mandible creates a larger volume for the tongue and floor of mouth.

These two effects result in the enlargement of the posterior airway space at the retroglossal and hypopharyl and hypopharyngeal region level.

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The maxilla is then cut and mobilized at the Le Fort I level.

The advancement is then achieved with the aid of a final occlusal splint or a stable final occlusion.

The maxilla is then fixated with 4 titanium plates and screws.

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• There are prebent OSA advancement plates that are designed for this purpose and have been shown to be more resistant to relapse.

• Araujo MM, Waite PD, Lemons JE: Strength analysis of Le Fort I osteotomy fixation: Titanium versus resorbable plates. J Oral Maxillofac Surg 59:1034-1039, 2001

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Because there is very often a large gap and minimal bony contact between the upper and lower segments of the maxilla,

Bone grafting is necessary to ensure good bony healing, better stability, and the minimization of relapse.

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Nasal septal defects and enlarged inferior turbinates can be treated via the Le Fort approach after down-fracturing of the maxilla .

The generally accepted magnitude of advancement was 10 mm.

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In patients with dysgnathia who undergo orthodontic treatment the maxilla and mandible will obviously not be advanced equal amounts.

An additional procedure to complement the MMA is the GGA.

• Riley RW, Powell NB, Guilleminault C: Obstructive sleep apnea syndrome: a surgical protocol for dynamic upper airway reconstruction. J Oral Maxillofac Surg 51:742-747, 1993

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• This could be done via the rectangular osteotomy technique popularized by Riley et al

• or an inferior horizontal geniotomy; the standard chin osteotomy used in orthognathic surgery.

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• This technique increases the magnitude of repositioning of the genioglossus, geniohyoid and digastric muscles.

• Riley RW, Powell NB, Guilleminault C: Obstructive sleep apnea syndrome: a surgical protocol for dynamic upper airway reconstruction. J Oral Maxillofac Surg 51:742-747, 1993

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Simultaneous adjunctive soft-tissue procedures can be considered during the MMA procedure.

pharyngeal soft-tissue procedures performed simultaneously with MMA may result in airway compromise secondary to bleeding and swelling.

These procedures include surgery to the soft palate, tonsils, and the tongue. These cases may need surgical tracheostomy,

prolonged endotracheal intubation or continuous positive airway pressure use for the period of postoperative edema.

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In addition, any tension on the soft-tissue closure from the skeletal advancement may lead to poor healing or even fibrosis and scarring.

Nonpharyngeal procedures, such as nasal procedures, cervicofacial liposuction, or lipectomy can be done simultaneously with MMA .

• Prinsell JR: Maxillomandibular advancement surgery in a site-specific treatment approach for obstructive sleep apnea in 50 consecutive patients. Chest 116:1519-1529, 1999

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Complications

• There are no major complications reported for the MMA procedure. Various authors have mentioned some minor complications.

• As the advancement of the mandible is often 10 mm or greater, the incidence of permanent hypesthesia of the lower lip is one of the commonest problems.

• Li KK, Troell RJ, Riley RW, et al: Uvulopalatopharyngoplasty,• maxillomandibular advancement, and the velopharynx. Laryngoscope

111:1075-1078, 2001

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• Studies have shown long term hypesthesia to be in the range of 13% and 20%. If there is no concurrent orthodontic treatment, postoperative occlusal changes, such as malocclusion and open bites, are relatively common.1

• Li KK, Troell RJ, Riley RW, et al: Uvulopalatopharyngoplasty,• maxillomandibular advancement, and the velopharynx. Laryngoscope

111:1075-1078, 2001

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This could result in the need for reoperation, postoperative orthodontic treatment, or postoperative prosthodontic rehabilitation.

When there has been previous or concurrent soft palate surgery to stiffen or shorten the palate, velopharyngeal insufficiency can occur.

Velopharyngeal insufficiency results in a lack of palatal closure and allows air escape during speech and swallowing difficulty.

• Li KK, Troell RJ, Riley RW, et al: Uvulopalatopharyngoplasty,• maxillomandibular advancement, and the velopharynx. Laryngoscope 111:1075-1078,

2001

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Another complication

• Temporo-mandibular disorder(TMD).The TMD is caused by the alteration in the

condylar position and increased joint pressure from the large mandibular advancement.

Pre-existing TMD is a risk factor that may drastically increase the likelihood of postoperative TMD.

Additional reported concerns that may arise are limited range of motion, sinus dysfunction and decreased bite force.

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• These complications have been observed more frequently in older patients.

• some other minor complications, such as local infection, an oro nasal perforation that healed spontaneously, and maxillary pseudo-union resulting in instability and that required bone grafting

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• Minimal postoperative difficulties with a mean hospital stay of 1.6 days, no significant impairment from the hypesthesia, and good patient acceptance of their facial changes.

• Waite et al also showed 95% patient satisfaction despite the minor complaints.

• . Waite PD, Wooten V, Lachner J, et al: Maxillomandibular advancement surgery in 23 patients with obstructive sleep apnea syndrome. J Oral Maxillofac Surg 47:12561261,

• 1989

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Advances in MMA

In the presence of modern technology,researchers and clinicians have started using computed tomography (CT) and magnetic resonance (MR) scans to evaluate the posterior airway 3-dimensionally.

This is superior to the widely used 2 dimensional cephalograms

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Cephalometric analysis of the airway has been well established and permits measurements at key anatomical locations.

A CT and MR provide extremely accurate distance and area measurements of the airway in all dimensions, there

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• In a recent study, 20 patients who underwent MMA had CT scans preoperatively and following surgery to analyze the morphologic changes of the airway.

• The results demonstrated significant increase in both the anteroposterior and lateral airway dimensions after MMA surgery.

• Solow B, Skov S, Ovesen J, et al: Airway dimension and head posture in obstructive sleep apnoea. Eur J Orthod

• 18:571-579, 1996

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Another area of interest is the emergence of the “quality-of-life” dimension.

This represents the functional effect of an illness and its consequent therapy upon a patient, as perceived by the patient.

It has been a neglected dimension as clinicians have been treating patients based on results of objective investigation.

• Schipper H, Clinch JJ, Olweny CLM: Quality of life studies: Definitions and conceptual issues, In Spilker B (ed): Quality of Life and Pharmacoeconomics in Clinical Trials (ed

• 2). Philadelphia, PA, Lippincott-Raven, 1996, pp 11-23

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Nowadays,quality of life is increasingly valued as an important aspect of patient care.

There have been very few studies that examined the changes in the quality of life after surgical procedures for OSA. Lye recently reported on MMA having equally high success in achieving significant improvement in the area of quality of life.

• Lye KW, Waite PD, Meara D, et al: Quality of life evaluation of maxillomandibular advancement surgery for treatment of obstructive sleep apnea. J Oral Maxillofac Surg 66:968-972, 2008

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conclusion,

There is strong evidence to support MMA as one of the most efficacious surgical procedure for the treatment of OSA.

It is a safe procedure and the more commonly noted complications are relatively minor as compared to the risk of inadequately treated OSA.

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There have been some modifications to the technique and inclusion of some adjunctive procedures over the years.

There is also essential research being done to provide the latest information on this treatment which will help in our understanding and improve our management of the OSA patient.

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