두경부 악성종양 환자에서 조기 방사선치료를 위한 구강관리법에 대한 임상적 및 실험적 연구

Abstract

[한글]두경부 악성종양으로 방사선치료를 받는 환자에서 치성염증이 있는 치아의 관리는 다양한 변화를 거치면서 발전해 왔다. 초창기 방사선치료의 시대에는 방사선조사 기술도 미숙하고 치성염증으로 인한 방사선성 골괴사 위험도도 높아 방사선조사 범위에 들어있는 모든 치아를 발치했다. 그러나 방사선조사 방법이 개선되고, 방사선조사의 범위도 병소에만 국한해 선택적으로 좁게 적용할 수도 있게 되면서, 저작기능을 감소시키는 다수 치아들의 발치보다는, 가능한 한 보존적으로 저작기능을 유지시키기 위한 시도들과 방사선성 치성염증의 예방을 위한 방법들이 개발되고 있다. 즉, 방사선치료의 전체 과정동안에 치성염증에서 기인한 방사선성 골괴사를 방지하면서도 저작기능의 감퇴를 최소화하고자 방사선치료 시행 전에 과도한 감염치아는 발치를 시행하지만, 중등도 치아우식증이나 치주질환처럼 발치와 보존적 치료의 경계에 있는 치아들은 적극적인 치성염증 예방법들을 구사하면서 근관치료 등의 보존적 치료법을 적용함이 타당하다. 만약 발치의 적응증이 된다면 방사선치료 시작 전 최소 2주일 전에 발치를 시행하되, 가능한 한 조직손상을 줄이고 창상치유를 촉진시키기 위해 치조골성형 및 1차적 창상봉합술을 시행함이 바람직하다. 여기서 문제점은 발치를 시행하고 최소 2주일이 경과된 시점에서 방사선치료를 시작하는 것으로, 악성종양의 방사선치료가 시급한 상황에서 환자와 방사선 종양학과 의료진들이 이 기간을 기다리기가 어렵다는 것이다. 따라서 발치보다는 근관치료같은 보존적 관리법을 적용하거나 또는 발치를 시행하더라도 기다리는 기간을 1주일 이내로 단축시키는 대안에 대한 검토가 필요하고, 이를 임상에 적용하고 조직병리학적 연구를 시행함은 의미있는 작업이다. 이에 저자 등은 연세대학교 원주의과대학 원주기독병원에서 10년간의 임상경험과 동물실험을 통한 조직병리학적 연구로 다음과 같은 결론을 얻었기에 보고한다. 1. 방사선치료 전 치성염증 분포는 치주염이 75예(44.4%)로 가장 많았으며, 진행된 치아우식증 및 치수염 53예(31.4%), 치근단 염증 26예(15.4%) 순이었고, 이에 따른 치과치료는 치석제거 및 구강위생교육이 74예(42.5%)로 가장 많았으며, 근관치료 45예(25.9%), 발치 및 봉합술 24예(13.8%) 순이었다.2. 방사선치료 시행기간 내 치성염증의 급성악화 분포는 매우 소수로 치수염 3예, 진행성 치주염 1예, 치조골염 1예에 불과했으며, 이에 따른 치과치료는 3예는 약물요법만 시행하였으며, 2예는 근관치료를 시행하였다.3. 방사선치료 완료 후 1년간 치성염증의 급성악화 분포는 치수염 3예, 치근단 염증 2예, 진행성 치주염 2예, 골수염 2예, 봉와직염 2예 등에 불과했으며, 이에 따른 치과치료는 근관치료 4예, 절개 배농술 4예, 약물요법만 시행 3예, 발치 및 봉합술 1예 같은 비교적 보존적 관리가 주류를 이루었다.4. 방사선치료 완료 후 1년간 만성 치성염증은 치수염이 29예(36.3%)로 가장 많았고, 치근단 염증 25예(31.3%), 진행성 치주염 15예(18.8%) 순이었으며, 이에 따른 치과치료는 근관치료가 33예(37.5%)로 가장 많았고 발치 및 봉합술 16예(18.2%), 치수복조술 12예(13.6%) 순이었다. 5. 동물실험을 통해 조직병리학적으로 입증하고자 시행한 실험에서는 성견 6마리(72개 근관)의 만성 치근단 염증치아의 조기 방사선치료 시행 후 4주째 치근단 염증의 정도는 1차 근관치료를 시행한 실험군이 1차 근관치료 없이 조기 방사선치료를 시작한 대조군보다 염증의 정도가 통계학적으로 유의할 수준으로 적었다(p<0.001).6. 동물실험에서 치근단 농양치아의 발치 후 1주일 경과 후에 방사선조사를 시행한 실험군과 2주일 경과 후에 방사선조사를 시행한 대조군의 방사선조사 완료 후 발치창상 치유의 양호정도는 통계학적으로 유의할 만한 차이가 없었다(p>0.05). 이상의 결과에서 두경부 악성종양 환자에서 방사선치료 시행 전 발치의 적응증이 되는 치아들은 발치를 시행하고서 1주일 경과 후에 방사선치료를 시작하고, 무증상의 만성 치근단 염증치아는 발치가 아닌 1차 근관치료 등의 보존적 치료로 1주일 이내에 방사선치료를 시작함이 실험적으로 가능하고, 임상적으로 조기 방사선치료에 유용한 방법으로 사료되었다.

[영문]The approach to management of odontogenic inflammatory teeth in patients receiving head and neck radiation has undergone a variety of changes. In the earliest dental protocols, all teeth in the primary beam were extracted prior to radiation therapy, because of the risk of osteoradionecrosis by the less

sophisticated types of radiation.

But, improvements in the types of radiation used, smaller fields of radiation, and more selective application of radiation therapy have coincided with increasing concerns for the patient's masticatory function and increasing knowledge of preventive dental protocols. With heavy emphasis on the prevention of osteoradionecrosis from odontogenic infection during radiation therapy, the rational management approach for the patient has evolved, using preradiation extraction of actively

infected teeth, conservative care of teeth at marginal risk(i. e. moderate to advanced caries and periodontal disease) and aggressive dental prevention during and after radiation therapy for the remaining dentition.

Teeth requiring extraction before radiotherapy should be removed as long as possible before the initiation of radiation therapy. Conventionally, a minimal 2-weeks waiting primary healing period is recommended. Dental extraction should be performed as atraumatically as possible, with care being given to

ensure minimal tissue trauma. All irregular or sharp edges of bone should be eliminated and the primary closure is suggested to ensure the proper wound healing.

Although the 2-weeks waiting primary healing period is ideal, it is not uncommon for the radiotherapist and the cancer patient to feel an urgent need to proceed with radiotherapy despite the need for dental care.

Therefore, alternative approaches for the early radiotherapy, including conservative endodontic treatment and 1-week waiting primary healing period after dental extraction at the time of radiotherapy, were considered on our Department of Dentistry, Wonju Christian Hospital, Wonju College of Medicine,

Yonsei University.

The authors report the clinical application study during 10 years of oral care for early radiation therapy in the head and neck cancer patients with odontogenic inflammatory lesions. And then, the experimental study of oral care for early radiation therapy is also reported to attain a rational evidence of the present clinical methods. The results obtained are as follows:

1. On the investigation about distribution of regions of head and neck cancer, the supraglottic carcinoma(28.3%) was the most frequent, followed by hypopharynx (15.0%) and nasopharynx (11.7%).

2. On the investigation about distribution of related therapies of radiotherapy, the combined therapy of radiotherapy and chemotherapy(40.8%) was the most frequent, followed by combined therapy of radiotherapy and surgery (23.3%) and only radiotherapy(20.0%).

3. On the investigation about distribution of the irradiation quantity for head & neck cancer, 6,000~below 7,000 cGy & above 7,000 cGy were the most frequent(35.8%) together, followed by 5,000~below 6,000 cGy(15.8%) and below 5,000 cGy (12.5%).

4. On the investigation about distribution of odontogenic inflammatory lesions before radiotherapy for head and neck cancer, the periodontitis(44.4%) was the most frequent, followed by advanced caries and pulpitis(31.4%) and asymptomatic periapical inflammation(15.4%).

5. On the investigation about distribution of dental treatment contents of the odontogenic inflammatory lesions before radiotherapy for head and neck cancer, scaling & oral hygiene instruction(42.5%) was the most frequent, followed by primary endodontic treatment(25.9%) and dental extraction & primary

closure(13.8%).

6. The acute worse cases of odontogenic infection during radiotherapy for head & neck cancer were minimal, such as, pulpitis (3 cases), periodontitis(1 case) and alveolar osteitis (1 case).

7. The numbers of dental treatment contents by acute worse cases of odontogenic infection during radiation therapy for head & neck cancer were also minimal, in which the treatment contents consisted of only medication prescription (3 cases), endodontic treatment (2 cases) and the other dental care (1 case).

8. The acute worse cases of odontogenic infection during the 1 year after radiotherapy were minimal, in which the cases consisted of pulpitis(3 cases), periapical inflammation(2 cases), advanced periodontitis(2 cases), osteomyelitis(2 cases) and cellulitis(2 cases).

9. The numbers of dental treatment contents of the acute worse cases of odontogenic infection during the 1 year after radiotherapy for head & neck cancer were minimal, in which the treatment contents consisted of endodontic treatment (4 cases), incision & drainage (4 cases) and only medication prescription (3 cases).

10. On the investigation about distribution of chronic advanced cases of odontogenic inflammation during the 1 year after radiotherapy, the pulpitis (36.0%) was the most frequent, followed by periapical inflammation(31.3%) and periodontitis(18.8%).

11. On the investigation about distribution of the dental treatment contents of the chronic advanced odontogenic inflammatory lesions during the 1 year after radiotherapy, endodontic treatment(37.5%) was the most frequent, followed by

dental extraction & primary closure(18.2%) and conservative pulp capping (13.6%).

12. On the investigation about the distribution of chronic long sustained oral complications over 1 year after radiotherapy in the head & neck cancer patients, xerostomia(32.7%) was the most frequent, followed by dysphagia (20.4%) and mucositis (19.5%).

13. For the purpose of histopathologic study about the clinical application effect during recent 10 years, the authors had the animal experiments for the possibility of the early endodontic treatment before radiotherapy. Statistically, the new experimental group, which had the primary early endodontic treatment by use of vitapex medication, had less periapical inflammation than the conventional control group with no endodontic treatment before radiation therapy.

14. For the purpose of histopathologic study about the clinical application effect during recent 10 years, the authors also had the animal experiments for the possibility of early radiation therapy in spite of the dental extraction wounds.

Conventionally, after teeth requiring extraction before radiotherapy was removed, the above 2-weeks waiting primary healing period of extraction wound was essentially required for the prevention of future wound complications, such as,radiation osteitis and osteoradionecrosis during & after radiotherapy. But, the new experimental group, which had a minimal 1 week waiting primary healing period, had similar frequency of the good dental extraction wound healing statistically with the conventional control group, which had a minimal 2-weeks waiting primary healing period.

Based on the above, the authors concluded that a minimal 1-week waiting primary healing period for oral care before radiotherapy was proper in the clinical dentistry for the early radiotherapy in head and neck cancer patients.