Pre radiation therapy dental prophylaxis

Cancer patients often require radiation therapy as part of their treatment plan. Radiation

therapy uses high-energy rays or particles to kill cancer cells or shrink tumors. While

radiation therapy is quite effective in treating cancer, it can also damage healthy cells in the

treated area. One area that is particularly susceptible to damage from radiation therapy is the

mouth. Radiation directed at head and neck cancers can injure the tissues of the oral cavity

including the gums, tongue, cheeks and lips. Damage to these tissues increases the risk of

complications like pain, infection, and bleeding. It may also negatively impact a patient's

ability to eat, speak and swallow.

To minimize these types of complications, dental assessments and treatment are

recommended prior to head and neck radiation therapy. This pre-treatment dental care is

known as dental prophylaxis. The goal of dental prophylaxis is to improve oral health and

reduce infections so patients can better tolerate radiation therapy. It involves identifying and

addressing any dental issues or infections that could be exacerbated by radiation exposure.

Common components of dental prophylaxis include dental cleanings, exams, x-rays, fillings,

extractions and Root Canal Therapy (RCT). Periodontal treatments like scaling and root

planing may also be performed to reduce inflammation and promote healing of gum tissues.

The dental team works closely with radiation oncologists to schedule prophylactic dental

treatment in coordination with the planned course of radiation therapy. Dental work is

typically completed 4-6 weeks before radiation starts to allow for healing of invasive

procedures and extraction sites. Any untreated infections or dental diseases are resolved at

this stage to reduce post-radiation complications. Patients also receive detailed oral hygiene

instructions and recommendations tailored to their needs. Following prophylaxis, daily oral

self-care practices like gentle brushing, special mouth rinses and regular dentist checkups

become very important during and after radiation therapy.

There are several important reasons why dental prophylaxis is recommended before head and

neck radiation therapy:

1. Radiation Sensitivity: Radiation therapy makes dental tissues like bone, gums and tooth

pulp more sensitive to bacterial infections. Any existing cavities, partially erupted wisdom

teeth or periodontal diseases are likely to worsen dramatically during treatment without prior

intervention. Pre-treatment dental care aims to eliminate these potential sites of pain and

infection.

2. Risk of Osteoradionecrosis: One of the most severe complications of head and neck

radiation is osteoradionecrosis or ‘ORN’ of the jawbone. This is a condition where the bone

tissue in the jaw dies due to reduced blood supply following radiation exposure. It occurs

most commonly after dental extractions during or soon after radiotherapy. By completing all

necessary dental extractions before radiation starts, the risk of ORN is significantly lowered.

3. Difficulty with Post-Radiation Extractions: Extractions become considerably more

challenging after radiation. The inflamed and friable tissues of the oral cavity tend to tear or

bleed excessively during procedures. Their slower healing impedes proper oral hygiene and

increases infection risks. It is deemed safer to complete extractions upfront before tissues are

damaged by radiation.

4. Avoidance of Interruptions: Stopping radiation partway through to accommodate urgent

dental treatment is avoided whenever possible. Treatment breaks or delays negatively impact

cancer control outcomes. Pre-treatment dental care prevents such unplanned interruptions in

the radiotherapy schedule.

5. Marginal Tolerance to Radiation Effects: Some patients can have low tolerance to oral

complications of radiation due to advanced cancer stage, co-morbid medical conditions or

poor nutritional status. Early dental treatment helps minimize the cumulative radiation-related

effects they may experience in the oral cavity.

6. Promotion of Healing: Bony infections, cysts and granulomatous tissues in the jaws are

barriers to normal post-irradiation wound healing. Pre-treatment resolution of these issues

supports improved healing capability and faster recovery from radiotherapy side effects.

7. Alleviation of Pain: Conditions like dental abscesses, cellulitis or exposed pulp are

extremely painful when aggravated by radiation. Removing these sources of discomfort

before therapy enhances patients’ quality of life during cancer treatment.

8. Enhanced Adherence to Radiotherapy: Oral health complications pose an impediment to

completing radiation on schedule for some patients. Dental prophylaxis helps patients comply

better with their radiotherapy plan by relieving pain, improving function and bolstering self-

esteem.

The dental prophylaxis evaluation usually involves a comprehensive oral exam by a radiation

oncologist and dentist experienced in managing dental issues pre- and post- radiation therapy.

Together they identify teeth that need extractions versus root canal treatment based on factors

like location, prognosis, restorability and risk of ORN. Panoramic x-rays are typically taken

to check for abscesses, cysts or pathology of the jaw bones. Patients also undergo periodontal

probing to assess pocket depths and note sites prone to future complications. Findings from

these assessments direct the customized dental treatment plan for each patient.

Scaling and root planing are performed as a part of prophylactic periodontal treatment to

minimize inflammation of the gums and reduce pathogens. This non-surgical procedure

gently scrapes away plaque and tartar buildup from below the gumline and smooths rough

root surfaces. It is essential for periodontally involved patients and those with pre-existing

gum disease before radiation. Studies show scaling alone leads to an average 25% reduction

in post-radiation complications like mucositis. With the addition of improved homecare

practices, prophylactic scaling further reduces risk of infection, pain and interruptions in

radiotherapy.

Another important pre-treatment intervention relates to partial or full denture wearers. Ill-

fitting, broken or contaminated dentures inhibit good oral hygiene during radiotherapy and

promote fungal/bacterial infections. Therefore, these appliances usually need replacement,

reline or repair as part of the dental prophylaxis. Patients are educated about appropriate

denture care and advised regarding continued, modified wear versus discontinuation during

radiation based on individual tolerance levels. In summary, the aim of preventive periodontal

and prosthetic interventions is to establish the healthiest possible oral environment prior to

radiation insult.

Dental restorative care including fillings, crown lengthening and endodontic procedures form

an integral aspect of dental prophylaxis as well. Existing restorations or tooth structures

vulnerable to future breakdown receive necessary buildups or RCT to prevent pain and

abscessing during radiotherapy. This is especially true for posterior teeth in close proximity

to the radiation field. Teeth deemed non-restorable or problematic for healing are usually

extracted prophylactically. Recent evidence demonstrates lower risk of delayed post-radiation

complications with this conservative approach versus repeated extractions later.

Although routine dental cleanings before radiation therapy are recommended, special

precautions are followed to minimize bacteremia. Antibiotic coverage is initiated after

discussing risks/benefits with the radiation oncologist/medical oncologist. Scaling and root

planing is performed using ultrasonic inserts that produce less aerosol/spatter. High volume

evacuations also help limit bacteria spread. These protective measures become even more

crucial for medically compromised patients on chemotherapy or with reduced

immunocompetence from their cancer itself. Careful aseptic techniques minimize any dental

procedure-related infectious sequelae.

Patients are counselled to maintain stringent oral hygiene during radiotherapy as well due to

heightened caries and periodontal disease susceptibility. In addition to twice daily brushing,

antiseptic or antibiotic mouthwashes are prescribed based on individual presentation.

Chemotherapeutic agents further elevate risk for oral mucositis and caries by impairing

salivary flow and taste sensations. Nutritional counseling stressing a soft, non-irritating diet is

an integral component of pre-treatment education. Symptomatic oral care products containing

anesthetics or coatants are recommended to manage discomfort from mucositis and taste

changes as they manifest. Compliance with these supportive therapies go a long way in

mitigating radiation-elicited oral complications.

Appropriate medical clearance is obtained before complex dental treatment plans involving

multiple extractions, CT scans or sedation. For medically complex patients, antibiotic

prophylaxis and use of sedation/general anesthesia may be warranted to reduce postoperative

pain and failure to cope with dental visits. Such interventions demand extra vigilance with

airway management, hemodynamic monitoring as well as resuscitation precautions that

dental teams delivering in-office prophylaxis are thoroughly trained to provide.

Bisphosphonate therapy is commonly given for advanced cancers with bone metastases to

reduce fractures from osteolytic lesions. While beneficial systemically, bisphosphonates

increase BRONJ (bisphosphonate-related osteonecrosis of the jaw) risks when combined with

dentoalveolar surgery or poor oral hygiene. Patients currently on or discontinuing

bisphosphonate medications require even more extensive pre-operative dental evaluation,

closer postoperative follow up and rigid implementation of preventive strategies to avert this

serious complication.

In conclusion, multidisciplinary cooperation between dental and medical teams remains

imperative to execute safe, comprehensive dental prophylaxis in preparation for head and

neck radiation therapy. Numerous clinical studies validate its crucial role in mitigating oral

health consequences of radiation exposure and optimizing treatment outcomes. With timely

intervention of susceptible dental issues, prophylactic dental treatment facilitates better

tolerance of subsequent radiotherapy by reducing infection incidence, ensuring comfort and

improving overall quality of life during cancer treatment. Most importantly, the collaborative

model of care detailed here exemplifies a biopsychosocial approach that places patient needs

at the forefront throughout their journey with oral, dental and medical conditions.

Several factors help determine the appropriate timing of dental prophylaxis before radiation

therapy. For most patients, 4-6 weeks is sufficient for routine dental treatment and healing.

However, those requiring complex surgeries such as bone grafting, dental implants or major

reconstructive procedures may need up to 3 months for recovery. The scheduling also

accounts for patient-related delays due to dental anxieties, medical issues or other competing

demands. Communication between the cancer care team and referring dentist is key to stay

aligned on treatment coordinates and timelines.

Assessing individual risk-benefit is always prudent before major pre-radiation extractions are

pursued. While minimizing osteoradionecrosis (ORN) is the goal, removing teeth in poor

prognosis areas increases the chance of initial ORN if osseous healing faces radiation insult

prematurely. Retention of such teeth may be reasonable provided thorough decontamination

is possible and extraction can be definitively delayed past radiotherapy.

For non-restorable molars in radiation fields, extraction within 3 months before starting is

optimal. However, extra-oral time of 4-6 weeks strikes the delicate balance between averting

ORN and allowing regional healing. Within 1 month of extraction, any exposed bone

experiences the maximum detrimental effects of concomitant radiation on wound repair.

Therefore, surgical sites beyond initial recovery require even closer follow up during

radiotherapy.

For lower third molars partially erupted or lying over the mandibular canal, potential

neuropathic pain with tumor progression should factor into retention versus removal decision

making. Thorough informed consent covering ORN risks aids management discussions.

Factors favoring prophylactic extraction include advanced age, insufficient root development

and angulation preventing adequate access post radiation. Meticulous socket irrigation and

drainage after prophylactic surgery remains essential with bisphosphonate use also in the

mix.

Root fractures at the furcation or cemento-enamel junction pose challenges by facilitating

caries/periodontal disease progression. Restorations become less predictable over time in

irradiated patients due to tissue atrophy. Although endodontic-periodontal lesions may linger

long term, their prior intervention supports healing and prevents further sequelae during

radiotherapy. Post-treatment plaque control emerges as the key to optimize long term success.

Patients with pre-existing exfoliated, mobile or carious teeth in the radiation field benefit

from prophylactic extraction considering limited post-irradiation treatment options. However,

vital teeth near and within fields warrant root canal treatment and preventive resin

restorations where possible to improve prognosis and maintain oral function. Clinicians

should tailor the pre-radiation treatment strategy to maximize tooth preservation while

minimizing complications.

Addressing other oral infections involves drainage/incision of dental abscesses with systemic

antibiotics as indicated. Fungal infections require anti-fungal therapy and repeat evaluations

until resolution. Though rare, viral lesions like oral hairy leukoplakia seen in

immunosuppressed patients often regress with highly active antiretroviral therapy (HAART).

Dentists coordinate such interventions and monitor response prior to radiotherapy not

interfering with cancer care timelines.

Periodontal attachment loss exceeding 50% frequently leads to exfoliation of teeth shortly

after radiotherapy despite prophylaxis. Conversely, even moderate to advanced periodontitis

(30-50% attachment loss) responds positively to non-surgical treatment, maintaining teeth

longer term. Still, dentists must weigh prognosis of deep pockets versus life expectancy while

outlining comprehensive plans for functional and aesthetic goals.

With excellent oral hygiene, localized chronic periodontitis can stabilize after successful

scaling and root planing pre-radiation. However, aggressive or generalized forms usually

necessitate adjunctive therapies like periodontal surgery or selective extractions to eliminate

microbial reservoirs and biofilm recolonization risks. Comprehensive treatment renders

positive outcomes while anteceding oncologic management needs.

As an adjunct prior to radiotherapy, antimicrobial photodynamic therapy or aPDT utilizes

light-activated disinfection to reduce oral microbial load. Research indicates aPDT may

decrease severity of radiation-induced oral mucositis and associated pain. Other preventive

procedures incorporating low level laser therapy or oral care gel also help ameliorate

mucositis by stimulating tissue repair and re-epithelialization. Their benefits encourage

further evaluation as safe, non-invasive adjuncts to standard prophylactic dental care.

Routine dental care during and after radiotherapy aims to maintain oral health, treat emerging

complications, and optimize future tooth longevity. However, additional precautions apply

when treating irradiated patients. Their reduced healing capacity, unpredictable responses and

uncommon side effects necessitate caution with procedures such as periodontal surgery,

implants, extractions or endodontics post-treatment. Consultation between dentists and

oncologists continually guides the changing standards of supportive care.

Radiation caries poses a chronic issue affecting up to 80% of survivors within 5 years

requiring multiple restorations or extractions. Elevated risk stems from hyposalivation,

dietary changes and local factors like poor plaque control potential. Preventive strategies

incorporate anticipatory restorative treatment of carious lesions found at prophylaxis.

Fluoride applications, sealants, frequent professional cleanings and fluoride varnish also play

protective roles until full saliva recovery.

Impaired vascularity and fibrosis can significantly delay ORN healing for over 6-24 months

even with prompt management. Early identification and combination therapies including

antibiotics, hyperbaric oxygen and surgical debridement optimize recovery, reducing

hospitalization times. Long term follow up by medical/dental providers sustains

improvements through supportive periodontal/restorative care post obturation.

Reprogramming of salivary glands post-irradiation leads to diminution or cessation of fluid

secretion often enduring for decades. Resultant hyposalivation fosters oral complications

affecting function, nutrition and quality of life. Adjunctive sialagogues like pilocarpine or

cevimeline stimulate residual gland tissue to partially restore flow and counter xerostomia

issues. Sugar-free chewing gums and saliva substitutes temporarily relieve symptomatically

in between.

Radiation changes to jawbones increases risk for dentoalveolar fractures during routine dental

procedures even years post treatment. Accessing roots becomes difficult requiring

radiographs for localization. Conventional endodontic treatment may become impossible

necessitating alternative access like laser, surgical or intentional root canal re-treatment

methods coupled with preventive restorations if feasible. Periradicular radiolucencies often

persist long-term requiring observation versus retreatment in asymptomatic teeth.

Long term follow up uncovers post-radiation temporalis muscle atrophy leading to trismus or

limited mouth opening within 1-5 years of treatment. Early range of motion exercises and

stretching under therapy guidance help prevent fibrotic contractures. Botox injection or

coronoidectomy may intervene when severe trismus impedes oral hygiene, nutrition or

prosthetic usage. Cumulative effects warrant lifelong surveillance referable to oncology

specialists familiar with radiation sequelae.

Radiation-induced osteoradionecrosis (ORN) has multifactorial etiology involving vascular

endothelial damage and hypoxic cellular injury to bone. Patients on antiresorptive

bisphosphonates for concurrent bone metastases face substantially increased risk of ORN, up

to 30-50%. Their prophylactic dental treatment requires even more meticulous planning and

support pre- and post- radiotherapy. Strict preventive strategies like chlorhexidine rinses aim

to maintain healthy oral microflora with minimal traumatic dental procedures as tolerated

over the patients' lifetime.

Head and neck cancer survivors confront long-term oncologic, functional and supportive

rehabilitation needs post-treatment. While cancer cure remains the priority, attention to oral

health optimizes quality of life outcomes through preservation of speech, deglutition,

aesthetics and self-esteem. Comprehensive dental prophylaxis serves as a crucial launching

pad towards this goal by mitigating radiotherapy's damaging oral effects and dental

complications through concerted medical-dental collaboration.

Multidisciplinary clinics continue advancing innovations facilitating survivorship care

including prosthodontic reconstruction, implant-based dental rehabilitation and microvascular

tissue transfer. State-of-the-art expertise allow restored form and function when conventional

approaches prove unpredictable after radiation damage. Intraoral scanners and 3D digital

workflows enhance esthetic and functional prosthetic rehabilitation. Their combined efforts

maximize optimal oral rehabilitation and cancer cure synergistically serving patients

holistically.

Late effects surveillance involves monitoring for secondary primary cancers potentially

induced by radiation exposure long term. Dental providers play pivotal roles in early

detection by comprehensive soft tissue exams at recall visits. Thorough palpation of cervical

lymph nodes guides timely oncologic referral while inspection aids detecting mucosal

malignancies potentially evolving from precancerous fields of radiodermatitis. Though rare,

heightened vigilance supports prompt diagnosis and management to optimize long term

survival.

Saliva substitutes and sialogogic agents emerged as viable options for xerostomia

management. However, none fully reconstitute natural saliva composition. Stem cell based

therapeutic strategies utilizing cultured salivary gland cells show early promise of

regenerating functional salivary tissues lost to radiation damage. Further refinement may

offer a permanent cure for devastating hyposalivation consequences if proven safe and

effective in clinical trials. Such innovative breakthroughs hold potential towards even

brighter futures for head and neck cancer survivors worldwide.

In summary, pre-radiotherapy dental care serves as a linchpin in the management of head and

neck cancer patients, guiding optimal treatment outcomes both short and long term. By

collaboratively addressing oral health issues before initiation of radiation, providers harness

teamwork to simultaneously facilitate radiotherapy administration, minimize oral

complications, maximize oral function, preserve teeth and support survivors' quality of life at

each stage. While continual progress remains ongoing, the foundational principles of

thorough risk assessment, individualized care plans and lifelong follow up detailed here

exemplify dentistry's invaluable contributions towards improved cancer cure and survivorship

through integrated multidisplinary care.