PREVENTION AND TREATMENT

DISTINCTION BETWEEN

ACCIDENTS - events that occur during surgery

COMPLICATIONS – all the conditions that appear postoperatively

~early stage complications appear in the immediate postoperative period & interfere with healing

~late stage: during the process of osseointegration.

EARLY STAGE COMPLICATIONS

INVOLVE : maxillary sinus or mandibular bone soft tissues & nerve trunks adjacent to the implant site.•CAUSES - excessively traumatic surgical approach -bone overheating during osteotomy -bacterial contamination of the host site.

DURING FIRST FEW POST-OPERATIVE DAYS -edema, exudate & pain.CAUSES: bacterial contamination during surgery ~directly or indirectly.PREVENTION- of the infection mainly depends on asepsis -sterile working area -disinfection of perioral skin with povidone iodine & alcohol -disinfection of oral mucosa with 0.2% Chx(studies have shown reduction in infections 4.1% test group 8.7% control group by Chx use)

EDEMA

ACCUMULATION OF EXCESS PLASMA FLUID (transudate) in the interstitial spaces (at least 10% increase)

Edema is related to extent of surgical trauma & duration of surgery .

Negatively affects healing, and causes discomfort during food intake & oral hygiene maintenance.

Prevention - atraumatic surgical technique - minimal tissue damage - ice packs & administration of

corticosteroids

ECCHYMOSES & HAEMATOMAS

NOT COMMON CAUSES - long & complex procedures - lack of patient compliance with the instructions given for the postoperative period

-vessel fragility(esp. in elderly pt.) -failure to discontinue anti-platelet therapy before surgery•MANAGEMENT- topical skin application of heparin containing medications.

EMPHYSEMA

Rare complication; from a sudden rise of the intra-oral pressure. ie when the pt. sneezes

CLINICALLY - swelling of half of face; extending at times to neck & thorax - crackling sound heard upon palpation• MANAGEMENT-massages & compression with ice packs .• PREVENTION- avoid use of high velocity instruments to prepare the bone bed or irrigation of the wound with hydrogen peroxide.

BLEEDING

Causes - failure to stabilize flap -tearing of soft tissues -masticatory trauma -early temporization and inappropriately modified temporary prosthesis.•MANAGEMENT- compression & tamponade with surgical gauzes soaked in tranexamic acid.

- if bleeding persists, re-elevate flap, remove clotted blood & place new sutures to immobilize the soft tissue and promote clot formn. And stabilization.

FLAP DEHISCENCE

Is the opening of the surgical wound edges exposing implant head &/or surrounding bone tissue.

Causes - thin mucosa - failure to ensure passive re-approximation &

closure of flap margins (thus unable to counter intramural mechanical stress- due to muscle and bone interaction)

- insufficient or extensive tension on the suture(leads to soft tissue necrosis) - functional movements, mastication,

phonation or deglutition.

Causes contd..

- Previous radiation therapy which affects flap vascularity- Incomplete tightening of the cover screw (due to presence of blood residues)- Bone debris trapped under the periosteum- Cigarette smoking & local effects of nicotine (cytotoxic & vasoactive substances) & systemic (altered granulocytes & T-cells), impaired production of antibodies & vasomotor substances.

If small If small If large If large

no surgical correction, as the granulation tissue which forms would promote healing .

granulation tissue formation process lasting >2 wks may require refreshing the epithelial wound margins

removing the sutures & re-suturing.

Treatment - based on extent of exposure

Prevention of Dehiscence :

Careful preoperative assessment of the soft tissues, to measure the amount of keratinized mucosa present & planning of augmentation procedures as appropriate.1.Minimally invasive flap elevation & reflection with careful removal of any bone debris 2.Proper suturing3.Sensible temporization with appropriate modifications; rebasing & relining4.Delaying the use of removable dentures until 2 wks after surgery

SENSORY DISORDERS

Results from injuries to the nerve trunk May lead to hyperesthesia, hypoesthesia or

anesthesia. SYMPTOMS- numbness, tingling, hot & cold,

pain, swelling, hardening, burning, loss of saliva, prickling, tickle, electrical shock sensation, itch.

lower jaw more affected - lower lip 54-64%, chin 46-58%, gum tissues 32-45%, tongue 11-16%

Reversible Reversible Permanent Permanent

Compression by edema or hematomas

Excessive stretching (>8% elastic limit) of the mental nerve during flap reflection

Injuries to inferior alveolar nerve or mental nerve during osteotomy leads to permanent sensory alteration along with hyperalgesia.

Nature of damage

Early stage Early stage Late stage Late stage

Immediately after injury occurs

Assessment of symptoms

X-rays performed No radiographic

changes - wait & see attitude is advisable since the symptoms may result from

"stunned nerve syndrome" (neuropraxia)

When symptoms persist or worsen

Clinical investigations- mechanoreceptive, thermal, electric,nociceptive & chemical tests repeated monthly, gustatory sensitivity tests

Lab tests -blink reflex test, Computerised tomography, nuclear magnetic resonance

Diagnosis

Immediate postoperative periodImmediate postoperative period

First month after surgeryFirst month after surgery

Combination drug therapies with NSAIDs, cortisones, proteolytic enzymes, antibiotics & vit C & E - to reduce nerve trunk compression by edema or hematomas

To promote nerve regeneration - vit C & D, vasodilators & ozone therapy (to prevent ischemia), magneto therapy, low level laser therapy & transcutaneous electric nerve stimulation (TENS)

nerve reconstruction- 1)neurorrhaphy 2) grafting 3) tubulization

Treatment

Late: MAXILLARY SINUSITIS

As a result of bacterial contamination during surgery or healing for wound dehiscence or implant placement into sinus

ACUTE CASES : pain, edema , swelling, reddened soft tissues

CHRONIC CASES: massive proliferation of mucosa, thickening of membrane, polypoid masses filling the sinus,decrease air in sinus and antral content become radiopaque

Treatment

Systemic therapy- antibiotics, Chx mouthwashes, saline irrigation through nasal orifice & use of nasal decongestants

If infection worsens or a dislodged implant in sinus - radical revision surgery of sinus & the antral mucosa completely removed.

Prevention - screening patients prior to surgery for sinustis or predisposing factors

- prophylactic antibiotic therapy -asepsis

MANDIBULAR FRACTURES

Rare - occur during osseointegration, after restoration or as a result of trauma.

Cause unknown; but fracture lines consistently pass through implant sites , as stresses converge & loss of bone density occurs .

Clinical signs : pain, swelling, impaired function & fistulae in fracture area

Diagnosis - clinical evaluation: movement of fractured segment, crackling sounds, signs of infection

-radiograph: radiolucent area through implant site

Treatment

Aligned fractures : antibiotic therapy +soft diet Mal-alinged fractures : reduction & immobilization

Prevention• Bone should be 7mm in height & 6mm in

width , if not ridge expansion or augmentation

• Avoid preparation of multiple bone beds• 5mm of hard tissue left between two sites• Avoid overscrewing of implant• Keep mandible at rest during healing

FAILED OSSEOINTEGRATION

Diagnosed at phase II surgery or restoration Results in loss of implant Causes: reduced healing, occlusal loading during

osseointegration, bone overheating(>47°C for 1min; radiographically visible after 2-4 wks)

Diagnosis: loosened implant & muffled sound upon percussion

Radiographically, radiolucent margin around implant

Treatment : removal of implant & debridement of the area

BONE DEFECTS

Can be horizontal or verticalCAUSES: 1. Direct trauma to bone or insult to

periosteum (reduced vascularity) 2. Decreased bone density 3. Implant placement into fresh extraction site 4. Wrong inclination of the implant 5. Excessive torque during insertion 6. Thin alveolar crest 7. Wound dehiscence during healing 8. Perforation of mucoperiosteum 9. Postoperative infection

Diagnosis

Patients are asymptomatic, thus radiographic examination of crestal bone-implant interface.

Treatment: •vertical defect a) <2mm -horizontal osteotomy b) >2mm- autologous bone graft ; if bone loss >25% grafting + membrane

uncovering of implant postponed by 2- 4months

Treatment contd..

Horizontal defect a) small- apical repositioning of soft tissues b) large - autologous graft + membraneuncovering of implants postponed by 3-4mnths prevention •Plan treatment according to quality & quantity of bone present

PERIAPICAL IMPLANT LESION

Is a pathological area of osteolysis at the apex of an osseo-integrated implant Cause: 1) accidental sectioning of the neurovascular bundle 2) pre-existing bone infection 3) foreign bodies or root fragments 4) sinus infections 5) contamination of implant 6) compression of bone debris , causing ischemia-necrosis & bone sequestration.

MAIN CAUSES:CONTAMINATION OF RECENTLY INSERTED IMPLANTS BY PATHOGENIC MICROFLORA. IT MAY BE FAVORED BY PRESENCE OF NECROTIC ANT TRAUMATIZED BONY TISSUE AND/OR IMPAIRED HOST MECHANISM.

C/F – EDEMA , SWELLING , PURULENT EXUDATE, PAIN ON PALPATION OR FISTULAE.RADIOGRAPHIC FEATURE- MARKED BONE RESORPTION.

TREATMENT: IF BONE IS NOT INVOLVED, A FLAP IS ELEVATED TO DRAIN THE ABSCESS AND REMOVE GRANULATION TISSUE.FOLLOWED BY SALINE IRRI.& ADM-LOCAL ANTIBIOTICS IF BONE RESORPTION+, A GUIDED BONE REGENERATION PROTOCOL WILL BE FOLLOWED.

POSTOP- ANTIBIOTIC THERAPY: IN BOTH THE ABOVE CASESAMOX+ CLAVULANIC ACID- 2G+METRON- 750MG & .12% CHX FOR ORAL HYGIENE.

Infection

Conclusions:

Local complications arising during the implant surgery are the main determinants of the outcome of the entire rehabilitation program.

Hence, the prevention of the complications sh be our main objective.

Therefore, careful clinical and radiographic examination, accurate treatment planning, proper planning of procedures, use of proper surgical techniques, appropriate instruments and correct management of healing and osseointegration are all the important aspects in preventing the complications.