J Oral Maxillofac 49:871-974.
Surg
1991
Treatment of a Large Odontogenic Keratocyst Using the Brosch Procedure HILLEL EPHROS, DMD,* AND HEE YOUNG LEE, DMDt
related to inadequate treatment.4.s.” The presence of epithelial rests or microcysts in the soft tissues overlying recurrent OKC lends credibility to this view. In one series of 52 OKC treated by enucleation, seven lesions recurred. In all seven cases, the overlying soft tissues contained epithelial remnants. I3 Secondary treatment included enucleation of the recurrences along with removal of the overlying soft tissues. There were no further recurrences after the second surgical procedure.13 Treatment of the OKC remains a controversial subject. Advocates of conservative treatment suggest that marsupialization yields results comparable to those obtained with more extensive surgery.14 The Brosch procedure, described in 1983 by Farmand and Makek,” offers advantages, particularly in the management of large multilocular OKC in the molar, angle, and ramus regions of the mandible. This procedure involves removal of the lateral cortical plate through a transoral approach, enabling the surgeon to visualize and completely enucleate the cyst. It also facilitates treatment of the remaining bone and excision of affected areas of overlying soft tissue.16 We have modified this procedure, taking advantage of techniques and instrumentation used in orthognathic surgery. In the case described below, a large OKC was treated using a modified Brosch technique.
Odontogenic keratocysts (OKC) are keratinizing, epithelial-lined cysts of the jaw. Sixty percent to 80% of reported cases occurred in the mandible, with males affected more often than females.‘** In approximately 10% of patients with OKC, the lesions represent a manifestation of the basal cell nevus syndrome.3 The clinical and radiographic features of OKC have been reviewed extensively2-5 and often suggest the diagnosis. However, the definitive diagnosis of OKC can only be made by histologic evaluation. Key histologic features include a thin epithelial lining, usually consisting of fewer than six cell layers in a corrugated or wavy pattern. The underlying connective tissue is composed of thin, irregular bundles of collagen, and often contains islands of epithelium that may represent daughter cysts.4 Other findings include variable degrees of keratinization, a low soluble protein content, and high levels of enzymes associated with collagenolysis and lysomal activity.6 The most important clinical feature of OKC is resistance to treatment. Recurrence rates from 6% to 60% have been reported after block resection, marsupialization, and enucleation with or without adjunctive chemical or cryosurgical therapy.7“2 Many theories have been proposed to explain the tendency of OKC to recur. Some attribute this to the unique histologic and chemical features of 0KC.4 It has been noted, in particular, that parakeratinized OKC behave more aggressively than the orthokeratinized variety. 1.4Other theories focus on the physical properties of these lesions, their size and location, and suggest that persistence is
Case Report An 18-year-old woman was referred to the oral surgery service at St Joseph’s Hospital and Medical Center on February 2, 1989 for the management of a large lytic lesion of the left mandible. The patient reported pain and swelling of 3 weeks’ duration, and had purulent discharge from the left mandibular retromolar pad region. The history was negative for any prior third molar extraction, cystectomy, or infection. The patient denied any neurosensory deficit associated with the left inferior alveolar nerve. On clinical examination, there was moderate left facial swelling, and the mandibular left buccal vestibule was expanded and indurated. A small amount of purulent discharge was expressed from an opening in the oral mucosa just posterior to the mandibular left second molar. The panoramic radiograph showed a large, multilocular, radiolucent lesion that occupied most of the left mandibular ramus and coronoid process, extending from the
* Associate Professor of Oral and Maxillofacial Surgery, Seton Hall University of Graduate Medical Education; Attending, Department of Dentistry, St Joseph’s Hospital and Medical Center, Paterson, NJ. t Attending, Department of Dentistry, St Joseph’s Hospital and Medical Center, Paterson, NJ. Address correspondence and reprint requests to Dr Ephros: 635 Broadway, Paterson. NJ 07514. 0 1991 American geons
Association
of Oral and Maxillofacial
Sur-
0278-2391/91/4908-0015$3.00/O
871
872 neck of the condyle to the amandibular left first molar region (Fig 1). Associated with the lesion was an impacted third molar located near the inferior border of the mandible. The inferior alveolar nerve was displaced to the posterior and inferior aspects of the ramus. The computed tomography (CT) scan showed an expansile lesion within the ramus, angle, and body of the mandible. Perforations of both the lateral and medial cortical plates were observed. No other abnormalities were seen. The lesion was biopsied transorally, and the results of the biopsy were consistent with an inflamed OKC. The patient was subsequently admitted to St Joseph’s Hospital and Medical Center on March 13, 1989, for surgical enucleation of the OKC. The patient’s medical history, physical examination, and admitting laboratory data were within normal limits. Furthermore, the physical examination was negative for any anomalies suggestive of basal cell nevus syndrome. In the operating room under general anesthesia administered via nasoendotracheal intubation, Ivy loops were placed bilaterally and the mandibular left first and second molars were removed. Then an incision for a mandibular ramus osteotomy was made in the left mandibular mucobuccal fold and extended anteriorly to include the gingival crevices of the first and second molars. Periosteal dissection was performed along the anterior border of the ramus and the tendinous attachments of the temporalis muscle were stripped from the coronoid process. After reflection of the medial and lateral soft tissues, a reciprocating saw was used to perform an osteotomy starting in the medial cortex at the base of the coronoid process. The osteotomy was extended down along the anterior border of the ramus and passed vertically through the lateral cortex in the region of the first molar (Fig 2). Posterolaterally, a vertical osteotomy through the outer cortex was accomplished extending from the sigmoid notch to the inferior border of the ramus. The lateral cortex of the posterior body and ramus and the entire coronoid process were sagittally split from the mandible using appropriate osteotomes and retracted laterally. The OKC was reflected in toto from the intact lingual plate and the specimen, consisting of the cyst and attached impacted third molar, coronoid process, and lateral cortex, was removed en bloc (Fig 3). The inferior alveolar neurovascular bundle was identified and appeared to be free of pathologic tissue. Medial cortical bone in the areas of
TREATMENTOFALARGEKERATOCYST
FIGURE 2. Diagram of procedure. The dotted lines correspond to the osteotomy sites on the left mandible. perforation was removed, and a peripheral ostectomy was performed on the remaining lingual and inferior walls of the defect using rotary and hand instruments. Soft tissues overlying the perforated areas were excised and submitted for histologic evaluation. After copious irrigation and careful inspection of the surgical defect, primary closure was obtained and no drains were placed. Maxillomandibular fixation was accomplished using the Ivy loops and 26-gauge stainless steel wire. Estimated blood loss was less than 150 mL. The patient recovered well from the surgery and the anesthesia, and was discharged from the hospital on March 14, 1989. Maxillomandibular fixation was removed 2 weeks later (Fig 4). A mild left inferior alveolar hypesthesia resolved 2 months postoperatively, and healing has been otherwise uneventful. After 16 months of follow-up, there has been no evidence of recurrence (Fig 5).
FIGURE 1. Preoperative panoramic radiograph demonstrating a large lytic lesion of the left mandible.
873
EPHROS AND LEE
FIGURE 3. Diagram showing specimen removed leaving inferior border of mandible and lingual cortex intact and accessible.
Discussion While there has been no consensus on the proper management of OKC, there is general agreement that complete removal of large OKC of the mandibular ramus may be difficult.3~5~‘5*‘6In large lesions, in particular, inadequate treatment may be the cause of persistence. This may not become evident until months or years after the initial surgery and then would most likely be termed recurrence. Advocates of conservative management of large OKC recognize the technical difftculties inherent in attempting complete enucleation and suggest that good results can be achieved with marsupialization. Some cases of successful treatment by marsupialization alone, or marsupialization followed by enu-
FIGURE 4. Radiograph taken 2 weeks after surgery showing the residual bony defect.
cleation, have been reported.i4 A major objection to this technique is the lack of a complete specimen for review. While the incidence of ameloblastomatous or malignant transformation is less than 2% in OKC, these cases do provide a compelling reason for enucleation, which provides the pathologist with a complete specimen. 1.7.8 The modified Brosch procedure, using familiar techniques and instrumentation, provides excellent exposure and access. Removal of the affected cortical bone in continuity with the cyst allows the surgeon to avoid having to separate cystic tissue from partially eroded cortical bone. This would normally be the most difficult part of the dissection and the part most likely to result in leaving pathologic tissue behind.3 Once the lateral cortex and cyst are removed, access to the remaining bone and surrounding soft tissues is quite good. This allows for removal of affected medial cortex and soft tissues overlying any perforations. It also allows for complete peripheral ostectomy or cryosurgical treatment of the bone cavity. The inferior alveolar neurovascular bundle can be directly visualized and preserved. This procedure is well suited for the management of large OKC of the molar, angle, and ramus regions of the mandible where resection and grafting would otherwise be considered. In 21 patients with large OKC involving the mandibular ramus treated by enucleation using the original Brosch procedure reported in one series, eight small (less than 1.5 cm) recurrences have been noted. ” Half of these recurrences were around teeth which were retained at the time of the initial surgery. The recurrences were treated by enucleation along with extraction of the involved teeth. Long term follow-up (3 to 20 years) after retreatment showed no new lesion. In the same series, the inferior alveolar nerve was exposed in 19 patients during the initial surgical procedure. Only one patient experienced a persistent sensory deficit.
874
TREATMENTOFALARGEKERATOCYST
FIG1 JRE 5. Radiograph taken 16 months postoperatively showing extensive bone repah . and remodeling.
The access and visibility achieved with the modified Brosch procedure allow the surgeon to remove large OKC while avoiding loss of mandibular continuity. Although mandibular continuity is maintained, immediate or delayed bone grafting may be desirable in some cases to restore full thickness and strength to the mandible and to maintain proper facial contour. When the body of the mandible has been affected and teeth lost, grafting also could facilitate the subsequent placement of endosteal implants. Finally, when treating very large OKC, placement of Ivy loops or arch bars at the beginning of the procedure is recommended. Their presence is useful should resection be necessary or a fracture occur during treatment. Maxillomandibular fixation may also be indicated in cases where the remaining strut of the bone is thin and narrow and postoperative limitation of function is warranted. Summary The modified Brosch procedure has been described. It represents a reasonable alternative to resection or marsupialization when treating large OKC that occupy the molar, angle, and ramus regions of the mandible. Extraction of teeth affected by the lesion as well as generous removal of partially eroded bone and overlying soft tissues may contribute to lower recurrence rates. Cryosurgical or mechanical treatment of the bony cavity, which is well visualized using this technique, may also lead to improved long-term results. Treatment must be followed by continued, careful observation of the patient.
References 1. Kakarantza-Angelopoulou E, Nicolatou 0: Odontogenic keratocysts: Chnicopathological study of 87 cases. J Oral Maxillofac Sum 48:593. 1990 2. Brannon RB: The odontogenic keratocyst. A clinicopathological study of 312 cases. Part I. Clinical features. Oral Surg 42:54, 1976 3. Wetmore SJ, Billie JD, Howe A, Wetzel W: Odontogenic keratocyst: Diagnosis and treatment. Otolaryngol Head Neck Surg 91:167, 1983 4. Zacharides N, Papanicolau S, Triantafyllou D: Odontogenic keratocysts: Review of the literature and report of sixteen cases. J Oral Maxillofac Sure 43: 177. 1985 5. Partridge M, Towers JF: The primordial cyst (odontogenic keratocysts): Its tumour-like characteristics and behavior. Br J Oral Maxillofac Surg 25:271, 1987 6. Magnusson BC: Odontogenic keratocysts: A clinical and histologic study with special reference to enzyme histochemistry. J Oral Path01 7:8, 1978 7. Anneroth G, Hansen LS: Variations in keratinizing odontogenie cysts and tumors. Oral Surg 54530, 1982 8. Chuong R, Donoff RB, Guralnick W: The odontogenic keratocyst. J Oral Maxillofacial Surg 40:797, 1982 9. Donatsky 0, Hjorting-Hansen E: Recurrence of the odontogenie keratocyst in 13 patients with the nevoid basal cell carcinoma svndrome. Int J Oral Sure 9:173. 1980 10. Emerson TG, Whitlock RIH, Jones JHlInvolvement of soft tissue by odontogenic keratocysts (primordial cysts). Br J Oral Surg 9:181, 1972 11. Sombatrium K, Petersen JK: Nevoid basal cell carcinoma syndrome: Conservative dental treatment. Int J Oral Surg 9:404, 1980 12. Wysocki GP, Sapp JP: Scanning transmission electron microscopy of odontogenic keratocysts. Oral Surg 42:494, 1976 13. Voorsmit RA, Stoelinga PT, Van Haelst VJ: The management of keratocysts. J Maxillofac Surg 9:228, 1981 14. Eyre J, Zakrzewska MB: The conservative management of large odontogenic keratocysts. Br J Oral Maxillofac Surg 23:195, 1985 15. Farmand M, Malek M: Late results following the Brosch procedure for treating large mandibular ramus cysts. J Maxillofac Surg 11:2 11, 1983 16. Webb DJ, Brockbank J: Treatment of the odontogenic keratocyst by combined enucleation and cryosurgery. Int J Oral Surg 13506, 1984
Surg
1991
Treatment of a Large Odontogenic Keratocyst Using the Brosch Procedure HILLEL EPHROS, DMD,* AND HEE YOUNG LEE, DMDt
related to inadequate treatment.4.s.” The presence of epithelial rests or microcysts in the soft tissues overlying recurrent OKC lends credibility to this view. In one series of 52 OKC treated by enucleation, seven lesions recurred. In all seven cases, the overlying soft tissues contained epithelial remnants. I3 Secondary treatment included enucleation of the recurrences along with removal of the overlying soft tissues. There were no further recurrences after the second surgical procedure.13 Treatment of the OKC remains a controversial subject. Advocates of conservative treatment suggest that marsupialization yields results comparable to those obtained with more extensive surgery.14 The Brosch procedure, described in 1983 by Farmand and Makek,” offers advantages, particularly in the management of large multilocular OKC in the molar, angle, and ramus regions of the mandible. This procedure involves removal of the lateral cortical plate through a transoral approach, enabling the surgeon to visualize and completely enucleate the cyst. It also facilitates treatment of the remaining bone and excision of affected areas of overlying soft tissue.16 We have modified this procedure, taking advantage of techniques and instrumentation used in orthognathic surgery. In the case described below, a large OKC was treated using a modified Brosch technique.
Odontogenic keratocysts (OKC) are keratinizing, epithelial-lined cysts of the jaw. Sixty percent to 80% of reported cases occurred in the mandible, with males affected more often than females.‘** In approximately 10% of patients with OKC, the lesions represent a manifestation of the basal cell nevus syndrome.3 The clinical and radiographic features of OKC have been reviewed extensively2-5 and often suggest the diagnosis. However, the definitive diagnosis of OKC can only be made by histologic evaluation. Key histologic features include a thin epithelial lining, usually consisting of fewer than six cell layers in a corrugated or wavy pattern. The underlying connective tissue is composed of thin, irregular bundles of collagen, and often contains islands of epithelium that may represent daughter cysts.4 Other findings include variable degrees of keratinization, a low soluble protein content, and high levels of enzymes associated with collagenolysis and lysomal activity.6 The most important clinical feature of OKC is resistance to treatment. Recurrence rates from 6% to 60% have been reported after block resection, marsupialization, and enucleation with or without adjunctive chemical or cryosurgical therapy.7“2 Many theories have been proposed to explain the tendency of OKC to recur. Some attribute this to the unique histologic and chemical features of 0KC.4 It has been noted, in particular, that parakeratinized OKC behave more aggressively than the orthokeratinized variety. 1.4Other theories focus on the physical properties of these lesions, their size and location, and suggest that persistence is
Case Report An 18-year-old woman was referred to the oral surgery service at St Joseph’s Hospital and Medical Center on February 2, 1989 for the management of a large lytic lesion of the left mandible. The patient reported pain and swelling of 3 weeks’ duration, and had purulent discharge from the left mandibular retromolar pad region. The history was negative for any prior third molar extraction, cystectomy, or infection. The patient denied any neurosensory deficit associated with the left inferior alveolar nerve. On clinical examination, there was moderate left facial swelling, and the mandibular left buccal vestibule was expanded and indurated. A small amount of purulent discharge was expressed from an opening in the oral mucosa just posterior to the mandibular left second molar. The panoramic radiograph showed a large, multilocular, radiolucent lesion that occupied most of the left mandibular ramus and coronoid process, extending from the
* Associate Professor of Oral and Maxillofacial Surgery, Seton Hall University of Graduate Medical Education; Attending, Department of Dentistry, St Joseph’s Hospital and Medical Center, Paterson, NJ. t Attending, Department of Dentistry, St Joseph’s Hospital and Medical Center, Paterson, NJ. Address correspondence and reprint requests to Dr Ephros: 635 Broadway, Paterson. NJ 07514. 0 1991 American geons
Association
of Oral and Maxillofacial
Sur-
0278-2391/91/4908-0015$3.00/O
871
872 neck of the condyle to the amandibular left first molar region (Fig 1). Associated with the lesion was an impacted third molar located near the inferior border of the mandible. The inferior alveolar nerve was displaced to the posterior and inferior aspects of the ramus. The computed tomography (CT) scan showed an expansile lesion within the ramus, angle, and body of the mandible. Perforations of both the lateral and medial cortical plates were observed. No other abnormalities were seen. The lesion was biopsied transorally, and the results of the biopsy were consistent with an inflamed OKC. The patient was subsequently admitted to St Joseph’s Hospital and Medical Center on March 13, 1989, for surgical enucleation of the OKC. The patient’s medical history, physical examination, and admitting laboratory data were within normal limits. Furthermore, the physical examination was negative for any anomalies suggestive of basal cell nevus syndrome. In the operating room under general anesthesia administered via nasoendotracheal intubation, Ivy loops were placed bilaterally and the mandibular left first and second molars were removed. Then an incision for a mandibular ramus osteotomy was made in the left mandibular mucobuccal fold and extended anteriorly to include the gingival crevices of the first and second molars. Periosteal dissection was performed along the anterior border of the ramus and the tendinous attachments of the temporalis muscle were stripped from the coronoid process. After reflection of the medial and lateral soft tissues, a reciprocating saw was used to perform an osteotomy starting in the medial cortex at the base of the coronoid process. The osteotomy was extended down along the anterior border of the ramus and passed vertically through the lateral cortex in the region of the first molar (Fig 2). Posterolaterally, a vertical osteotomy through the outer cortex was accomplished extending from the sigmoid notch to the inferior border of the ramus. The lateral cortex of the posterior body and ramus and the entire coronoid process were sagittally split from the mandible using appropriate osteotomes and retracted laterally. The OKC was reflected in toto from the intact lingual plate and the specimen, consisting of the cyst and attached impacted third molar, coronoid process, and lateral cortex, was removed en bloc (Fig 3). The inferior alveolar neurovascular bundle was identified and appeared to be free of pathologic tissue. Medial cortical bone in the areas of
TREATMENTOFALARGEKERATOCYST
FIGURE 2. Diagram of procedure. The dotted lines correspond to the osteotomy sites on the left mandible. perforation was removed, and a peripheral ostectomy was performed on the remaining lingual and inferior walls of the defect using rotary and hand instruments. Soft tissues overlying the perforated areas were excised and submitted for histologic evaluation. After copious irrigation and careful inspection of the surgical defect, primary closure was obtained and no drains were placed. Maxillomandibular fixation was accomplished using the Ivy loops and 26-gauge stainless steel wire. Estimated blood loss was less than 150 mL. The patient recovered well from the surgery and the anesthesia, and was discharged from the hospital on March 14, 1989. Maxillomandibular fixation was removed 2 weeks later (Fig 4). A mild left inferior alveolar hypesthesia resolved 2 months postoperatively, and healing has been otherwise uneventful. After 16 months of follow-up, there has been no evidence of recurrence (Fig 5).
FIGURE 1. Preoperative panoramic radiograph demonstrating a large lytic lesion of the left mandible.
873
EPHROS AND LEE
FIGURE 3. Diagram showing specimen removed leaving inferior border of mandible and lingual cortex intact and accessible.
Discussion While there has been no consensus on the proper management of OKC, there is general agreement that complete removal of large OKC of the mandibular ramus may be difficult.3~5~‘5*‘6In large lesions, in particular, inadequate treatment may be the cause of persistence. This may not become evident until months or years after the initial surgery and then would most likely be termed recurrence. Advocates of conservative management of large OKC recognize the technical difftculties inherent in attempting complete enucleation and suggest that good results can be achieved with marsupialization. Some cases of successful treatment by marsupialization alone, or marsupialization followed by enu-
FIGURE 4. Radiograph taken 2 weeks after surgery showing the residual bony defect.
cleation, have been reported.i4 A major objection to this technique is the lack of a complete specimen for review. While the incidence of ameloblastomatous or malignant transformation is less than 2% in OKC, these cases do provide a compelling reason for enucleation, which provides the pathologist with a complete specimen. 1.7.8 The modified Brosch procedure, using familiar techniques and instrumentation, provides excellent exposure and access. Removal of the affected cortical bone in continuity with the cyst allows the surgeon to avoid having to separate cystic tissue from partially eroded cortical bone. This would normally be the most difficult part of the dissection and the part most likely to result in leaving pathologic tissue behind.3 Once the lateral cortex and cyst are removed, access to the remaining bone and surrounding soft tissues is quite good. This allows for removal of affected medial cortex and soft tissues overlying any perforations. It also allows for complete peripheral ostectomy or cryosurgical treatment of the bone cavity. The inferior alveolar neurovascular bundle can be directly visualized and preserved. This procedure is well suited for the management of large OKC of the molar, angle, and ramus regions of the mandible where resection and grafting would otherwise be considered. In 21 patients with large OKC involving the mandibular ramus treated by enucleation using the original Brosch procedure reported in one series, eight small (less than 1.5 cm) recurrences have been noted. ” Half of these recurrences were around teeth which were retained at the time of the initial surgery. The recurrences were treated by enucleation along with extraction of the involved teeth. Long term follow-up (3 to 20 years) after retreatment showed no new lesion. In the same series, the inferior alveolar nerve was exposed in 19 patients during the initial surgical procedure. Only one patient experienced a persistent sensory deficit.
874
TREATMENTOFALARGEKERATOCYST
FIG1 JRE 5. Radiograph taken 16 months postoperatively showing extensive bone repah . and remodeling.
The access and visibility achieved with the modified Brosch procedure allow the surgeon to remove large OKC while avoiding loss of mandibular continuity. Although mandibular continuity is maintained, immediate or delayed bone grafting may be desirable in some cases to restore full thickness and strength to the mandible and to maintain proper facial contour. When the body of the mandible has been affected and teeth lost, grafting also could facilitate the subsequent placement of endosteal implants. Finally, when treating very large OKC, placement of Ivy loops or arch bars at the beginning of the procedure is recommended. Their presence is useful should resection be necessary or a fracture occur during treatment. Maxillomandibular fixation may also be indicated in cases where the remaining strut of the bone is thin and narrow and postoperative limitation of function is warranted. Summary The modified Brosch procedure has been described. It represents a reasonable alternative to resection or marsupialization when treating large OKC that occupy the molar, angle, and ramus regions of the mandible. Extraction of teeth affected by the lesion as well as generous removal of partially eroded bone and overlying soft tissues may contribute to lower recurrence rates. Cryosurgical or mechanical treatment of the bony cavity, which is well visualized using this technique, may also lead to improved long-term results. Treatment must be followed by continued, careful observation of the patient.
References 1. Kakarantza-Angelopoulou E, Nicolatou 0: Odontogenic keratocysts: Chnicopathological study of 87 cases. J Oral Maxillofac Sum 48:593. 1990 2. Brannon RB: The odontogenic keratocyst. A clinicopathological study of 312 cases. Part I. Clinical features. Oral Surg 42:54, 1976 3. Wetmore SJ, Billie JD, Howe A, Wetzel W: Odontogenic keratocyst: Diagnosis and treatment. Otolaryngol Head Neck Surg 91:167, 1983 4. Zacharides N, Papanicolau S, Triantafyllou D: Odontogenic keratocysts: Review of the literature and report of sixteen cases. J Oral Maxillofac Sure 43: 177. 1985 5. Partridge M, Towers JF: The primordial cyst (odontogenic keratocysts): Its tumour-like characteristics and behavior. Br J Oral Maxillofac Surg 25:271, 1987 6. Magnusson BC: Odontogenic keratocysts: A clinical and histologic study with special reference to enzyme histochemistry. J Oral Path01 7:8, 1978 7. Anneroth G, Hansen LS: Variations in keratinizing odontogenie cysts and tumors. Oral Surg 54530, 1982 8. Chuong R, Donoff RB, Guralnick W: The odontogenic keratocyst. J Oral Maxillofacial Surg 40:797, 1982 9. Donatsky 0, Hjorting-Hansen E: Recurrence of the odontogenie keratocyst in 13 patients with the nevoid basal cell carcinoma svndrome. Int J Oral Sure 9:173. 1980 10. Emerson TG, Whitlock RIH, Jones JHlInvolvement of soft tissue by odontogenic keratocysts (primordial cysts). Br J Oral Surg 9:181, 1972 11. Sombatrium K, Petersen JK: Nevoid basal cell carcinoma syndrome: Conservative dental treatment. Int J Oral Surg 9:404, 1980 12. Wysocki GP, Sapp JP: Scanning transmission electron microscopy of odontogenic keratocysts. Oral Surg 42:494, 1976 13. Voorsmit RA, Stoelinga PT, Van Haelst VJ: The management of keratocysts. J Maxillofac Surg 9:228, 1981 14. Eyre J, Zakrzewska MB: The conservative management of large odontogenic keratocysts. Br J Oral Maxillofac Surg 23:195, 1985 15. Farmand M, Malek M: Late results following the Brosch procedure for treating large mandibular ramus cysts. J Maxillofac Surg 11:2 11, 1983 16. Webb DJ, Brockbank J: Treatment of the odontogenic keratocyst by combined enucleation and cryosurgery. Int J Oral Surg 13506, 1984
