- Email: [email protected]
Analysis of surgical intervention in 60 cases of free-flap compromise in head and neck reconstruction
BAOMS Prevention of bar glass facial injury: from basic research implementation. 1 p Shepherd. University of Wales Medicine, Cardiff. UK.
to national College of
.
References I. Shepherd JP, Shapland M. Pierce NX et al. Pattern, severity and aetiology of injuries in urban violence J R Sot Med 1990; 83: 75-78 2. Shepherd JP, Shenfine P, Price M. Glass abuse and urban licensed premises J R Sot Med 1990; 83: 276-277. 3. Shepherd JP, Huggett R, Kidner G. Impact resistance of bar glasses. J Trauma 1993; 36: 936-939. 4. McLean W, Shepherd JP, Brann C et al. Risks associated with occupational glass injury in bar staff with special consideration of hepatitis B infection. Occup Med 1997; 47: 147-150.
on dentally qualified medical undergraduates schools, 1996-1997. p A. Cllur~bcrs. University School, Leeds, UK.
in British of Leeds
The population of dentally qualitied medical undergraduates in British medical schools has been studied on several occasions in the past. most recently by Magennis and 0ng.l an update of this sample having been presented at the BAOMS annual meeting in Buxton in June, 1997. The cohort of dental graduates currently in medical school in 1996. 1997 has now been studied. The information has been collected at a time when recent changes to both postgraduate medical education in general and the maxillofacial surgery training pathway in particular are entirely relevant to this group who represent the grass roots of the future of our specialty. Information was obtained by circulating a postal questionnaire. A broad range of issues was covered including: basic demographic information; details of dental and medical education; patterns of working whilst at medical school; BAOMS membership and future career intentions. An open section was included to allow respondents to comment on any issue which they felt to be of particular importance. The results of this survey are presented and comparison with previous ones made to identify trends which may have implications for future training and manpower considerations within our specialty.
Reference I. Magennis P, Ong T K. Survey of dental graduates medical schools and a comparison with previous Oral Maxillofacial Surg 1994: 34: 438445
Mulwmmud
Hospital.
In the mid 198Os, bar glasses were identified as a major cause of disfiguring maxillofacial injury in young adults.’ Subsequent research quantified this problem, identified the glass designs most responsible, described the circumstances of bar glass injury and investigated impact resistance and glass breakage characteristics in both epidemiological and laboratory studies.’ 4 The Home Office and the Criminal Injuries Compensation Authority subsequently confirmed the substantial levels of morbidity associated with these injuries. This maxillofacial injury research led to a campaign to introduce toughened pint and half pint capacity glassware in UK licensed premises. This involved a local (‘Face of Wales’) awareness initiative and national campaigning through principal charities such as Alcohol Concern, The BMA and the All Party Parliamentary Group on alcohol misuse. By spring 1997 approximately one third of 16 million straight-sided glasses were manufactured from toughened glass and -subsequently, the new Home Secretarv Jack Straw (‘Calling Time’. Home Office 1997) adooted this as part of a strategy to limit alcohol-related harm. In October 1997, the influential professional body the Brewers and Licensed Retailers Association made this national policy helping to ensure comprehensive national implementation.
Report medical Medical
Percutaneous
entering surveys. Br J
dilatation Department Swansea. UK.
tracbeostomy: the of Maxillofacial
Abstracts
227
difficult cases. .1. K. Surgery, Morriston
Percutaneous dilatation tracheostomy (PDT) is an evolving technique. Between March 1992 and January 1998, more than 400 percutaneous dilatational tracheostomies have been performed at the Department of Intensive Therapy, Morriston Hospital, Swansea. A small number of cases have been unsuccessful and required open tracheostomy. It is the purpose of this paper to discuss the complications and ditliculties that can arise from PDT and the measures that can be taken to minimize them.
A prospective trial comparing full and partial thickness skin for the repair of the radial free flap donor site. il. J Sidebottom.L. Stew~c J C DCV~M(I, ,I4. Moure. J. p Mrrger~nic. Regional Maxillofacial Unit. Walton Hospital. Liverpool, UK. Anecdotal reports have suggested various methods of repair of the radial donor site defect. Direct closure is likely to give the best aesthetic results, but this is often difficult to achieve. Partial thickness skin has been the accepted method of repair until recently, when full thickness grafts have been proposed. These have the stated advantages of having a donor site defect which is primarily closed and a thicker, more aesthetic recipient site result. To date, a comparative study of the outcome of these two methods has not been reported. All cases treated at the Regional Maxillofacial Unit, Walton Hospital, Liverpool having radial free flap reconstruction during the period I May 1996 to 31 December 1997 were randomly allocated to a full or partial thickness skin graft to repair the defect, A standard postoperative wound management protocol was adopted for both groups. Sixty-five patients have been assessed and the complication rates and aesthetic outcomes will be compared.
The nasolabial flap in intraoral reconstruction: a re-evaluation. !V. J ClurX, A. il. C. IV&h. G. A. Z&i. Maxillofacial Unit. Queen Alexandra Hospital, Portsmouth, UK. The nasolabial flap has historically been a versatile flap in facial and intraoral reconstruction. The use of the flap for intraoral reconstruction has reduced with the introduction of microvascular free flap reconstruction, which has undoubtedly improved the quality and scope of reconstructive options. Free flap reconstruction, however, is not without its problems: the operations are often undertaken on compromised patients with an increased risk of complications; there ih also an acknowledged failure rate of between 5 and 10%. The purpose of our review was to retrospectively assess the use of the nasolabial flap in intraoral reconstruction over a 5-year period (1993-1997 inclusive) at the Queen Alexandra Hospital, the total number of cases for this period being 16. Assessment was carried out in terms of donor site scarring, intraoral flap appearance and function (regarding speech, eating and problems of flap hair). total operative time and postoperative complications. The results and an evaluation of the flap in present-day praclice are presented.
Analysis of surgical intervention in bead and neck reconstruction. Pkghun. Regional Maxillofacial Hospitals, Liverpool, UK.
in 60 cases of free-flap compromise J. C. Devine, J S. Bwwn, E. D. Unit. Walton Hospital. Aintree
The success rate of microvascular free-tissue transfer has been reported as being between 90 and 98’%, in recent reports. The need to return to theatre to attempt salvage of a compromised free flap can overstretch available resources and may affect the recovery time of the patient. We have analysed those cases that required surgical intervention for flap salvage in an attempt to highlight those factors that may be important in case selection and surgical technique.
228
British
Journal
of Oral and Maxillofacial
Surgery
A total of 450 patients have undergone orofacial reconstruction using free-tissue transfer at the Regional Maxillofacial Unit, Walton Hospital, Liverpool between 1992 and 1997. The majority of these cases were immediate reconstructions following ablative surgery for head and neck malignancy. Surgical intervention in the immediate and early postoperative period was required in 60 cases to date, in response to clinical signs of potential or evident compromise of the free flap. We retrospectively reviewed these cases in an effort to identify and quantify causes of free-flap compromise in our series of patients and the subsequent management and outcome of free-flap salvage. A detailed account of our findings will be presented.
The use of neurotrophic factors to enhance lingual nerve repair. K. G. Smith, J M. Yates, I? II Robinson. Department of Oral and
Maxillofacial
Surgery, University of Sheffield, Sheffield, UK.
Microsurgical repair of damaged lingual nerves enhances regeneration but the level of recovery is variable and never complete. Recent studies on methods of improving recovery after peripheral nerve injury have reached a watershed, shifting from the technology of nerve repair, to the understanding of the cellular and molecular events occurring in the microenvironment of the tip of the regenerating axon. This has led to the proposed use of neurotrophic agents to support and guide axons, and hence enhance recovery. The present study investigates the efficacy of placing one of two such agents, nerve growth factor (NGF) or brain derived neurotrophic factor (BDNF) at the site of lingual nerve repair. In anaesthetized adult cats (alphaxalone and alphadolone acetate, 18 mg/kg i.m.) the left lingual nerve was sectioned and repaired by suturing the ends into a silicone tube, leaving a 1 mm gap between them. In 8 animals, the gap was filled with saline, and in each of two other groups, either 3 pg of NGF or 1 pg of BDNF (Alomone Laboratories, Jerusalem) was added. In all of the groups, the ends of the tube were sealed with feline fibrin glue. After recovery for 6 months the extent of functional recovery was evaluated electrophysiologically. The study found significant differences between the repair groups. NGF at the repair site resulted in an increase in the number of thermosensitive units, and both neurotrophic factors were followed by a reduction in conduction velocity; this would be compatible with an increase in axonal sprouting at the injury site. There was, however, no overall improvement in recovery. Thus, the application of these particular neurotrophic agents did not significantly enhance lingual nerve regeneration. Supported
by the Welleome
Trust
A histopathological and physical study of the bonding of ~50 composite resin to bone. M. J Hahn, R. M. Browne, .! W Frame, J G. Meechan, JR McCabe, ? Budaiya. Department of Oral and Facial
Surgery, Sunderland Royal Hospital, Sunderland; Dental Schools of Universities of Birmingham and Newcastle upon Tyne, UK. The aims of this study were to determine the histological response of bone to P50 composite resin using two different bonding agents - ART and All Bond-2 - and to measure the associated bond strengths. No histological data were found in the literature concerning the effects of bonding composite resin to bone in vivo. Shear bond strength determination of the adhesion of P50 to bone in vitro has been carried out previously. In this study, P50 was bonded to both the cortical and cancellous parts of the calvarial bone of 24 rabbits using surgically roughened areas and titanium discs as controls. The histological changes at one, four and eight weeks were compared. In the same rabbits, two composite discs were bonded to tibia1 bone and the shear bond strengths determined at the same time intervals. The results indicated that P50 composite resin can be bonded to vital bone without any significant adverse clinical or histological effects. The bond strengths (0.25-21.66 MPa) achieved were sufficient to justify further studies into the possible use of these materials for fracture fixation.
Bioglass@ Thompson,
4585 as a mouldable bone graft substitute. C. Chan, I. l? Robinson, P Revell, 1 Wilson, L. Hench. UMDS
Guy’s Hospital, London, UK. Introduction: Bioglass@ particulate has been shown to be bioactive in hard and soft tissues. However, used alone, it may be insufficiently cohesive for certain augmentation procedures. Addition of high-molecular-weight Dextran produces a mouldable bioactive material. Objective: To evaluate the behaviour of the bioactive putty in a femoral defect in rabbits. Materials and methods: Defects were created in the lateral femoral condyles in 51 New Zealand white rabbits and filled with one of the following: (1) autogenous bone; (2) BioglassQ (3) Bioglass@ mixed with Dextran; (4) mixture of (2) and autogenous bone; (5) mixture of (3) with autogenous bone. Six defects were left unfilled as controls. Healing of bony defects at two days, one, two, three, six and twelve weeks were studied histologically using Von Kossa, toluidine blue and vital bone markers. Results: There was no evidence of toxicity and all test sites were filled by the third week. Particulate was gradually incorporated into the new trabecular bone and was almost completely undetectable at 12 weeks. Control sites showed little or no infill. Conclusion: No difference between Bioglass@ and autologous bone was detectable and the addition of Dextran was without effect.
The osseointegration M. A. El Montaser,
of implants H. Devlin,
in laser-prepared bone. R. E. Lloyd, I? Sloan, M. Dickinson. University
Dental Hospital of Manchester, Manchester, UK. The object of the study was to determine the bone turnover surrounding titanium screw implants placed with an erbium-YAG laser, using a rat calvarial model. In each rat, a sagittal incision was made in the skin of the skull under general anaesthesia, and the periosteum gently reflected. A hole on each side of the calvaria was prepared with either the erbium-YAG laser or a metal burr. The bone was cooled continuously with physiological saline. After preparing the holes, selfthreading titanium screws were placed (diameter 1 mm) and the overlying tissues approximated and sutured. The rats were killed after 3 weeks. The lasered defects healed with a different histological pattern from the burr prepared defects. With the lasered defects, vital bone was deposited on a thin zone of necrotic bone. A layer of carbonization separated the vital from the non-vital tissue. The dura was perforated, and the laser caused a deeply penetrating fibrosis and oedema of the brain tissue, which was not present with the burr prepared defects. With both lasered and burr prepared defects, bone was deposited around the head of the implant outline at the ectocranial surface. A different histological pattern surrounds titanium implants placed with an erbium-YAG laser from those placed with a burr.
Towards a diagnostic index for investigation A. S. Davies, D. K. Riden, P Dubbins.
Maxillofacial Surgery Plymouth, Devon, UK.
and
of salivary
gland disease.
Departments of Oral & Radiology, Derriford Hospital,
The results of management of patients in Plymouth with disease of the major salivary glands was reviewed retrospectively. The diagnoses were grouped and the various investigations used were assessed for effectiveness and relevance in establishing the final diagnosis. The diagnostic groups studied were benign neoplasia, malignant salivary lesions, degenerative conditions, inflammatory or infective presentations, calculous and chronic obstructive disease and non-salivary lesions. The investigations used were clinical examination, ultrasound scanning, FNAC, plain radiography, CT or MRI scanning and sialography. Sensitivities, specificities and predictive values were derived for each modality in the diagnosis of each group. An index of diagnostic power was derived for each of the modalities. The factors affecting the clinical usefulness of each
to national College of
.
References I. Shepherd JP, Shapland M. Pierce NX et al. Pattern, severity and aetiology of injuries in urban violence J R Sot Med 1990; 83: 75-78 2. Shepherd JP, Shenfine P, Price M. Glass abuse and urban licensed premises J R Sot Med 1990; 83: 276-277. 3. Shepherd JP, Huggett R, Kidner G. Impact resistance of bar glasses. J Trauma 1993; 36: 936-939. 4. McLean W, Shepherd JP, Brann C et al. Risks associated with occupational glass injury in bar staff with special consideration of hepatitis B infection. Occup Med 1997; 47: 147-150.
on dentally qualified medical undergraduates schools, 1996-1997. p A. Cllur~bcrs. University School, Leeds, UK.
in British of Leeds
The population of dentally qualitied medical undergraduates in British medical schools has been studied on several occasions in the past. most recently by Magennis and 0ng.l an update of this sample having been presented at the BAOMS annual meeting in Buxton in June, 1997. The cohort of dental graduates currently in medical school in 1996. 1997 has now been studied. The information has been collected at a time when recent changes to both postgraduate medical education in general and the maxillofacial surgery training pathway in particular are entirely relevant to this group who represent the grass roots of the future of our specialty. Information was obtained by circulating a postal questionnaire. A broad range of issues was covered including: basic demographic information; details of dental and medical education; patterns of working whilst at medical school; BAOMS membership and future career intentions. An open section was included to allow respondents to comment on any issue which they felt to be of particular importance. The results of this survey are presented and comparison with previous ones made to identify trends which may have implications for future training and manpower considerations within our specialty.
Reference I. Magennis P, Ong T K. Survey of dental graduates medical schools and a comparison with previous Oral Maxillofacial Surg 1994: 34: 438445
Mulwmmud
Hospital.
In the mid 198Os, bar glasses were identified as a major cause of disfiguring maxillofacial injury in young adults.’ Subsequent research quantified this problem, identified the glass designs most responsible, described the circumstances of bar glass injury and investigated impact resistance and glass breakage characteristics in both epidemiological and laboratory studies.’ 4 The Home Office and the Criminal Injuries Compensation Authority subsequently confirmed the substantial levels of morbidity associated with these injuries. This maxillofacial injury research led to a campaign to introduce toughened pint and half pint capacity glassware in UK licensed premises. This involved a local (‘Face of Wales’) awareness initiative and national campaigning through principal charities such as Alcohol Concern, The BMA and the All Party Parliamentary Group on alcohol misuse. By spring 1997 approximately one third of 16 million straight-sided glasses were manufactured from toughened glass and -subsequently, the new Home Secretarv Jack Straw (‘Calling Time’. Home Office 1997) adooted this as part of a strategy to limit alcohol-related harm. In October 1997, the influential professional body the Brewers and Licensed Retailers Association made this national policy helping to ensure comprehensive national implementation.
Report medical Medical
Percutaneous
entering surveys. Br J
dilatation Department Swansea. UK.
tracbeostomy: the of Maxillofacial
Abstracts
227
difficult cases. .1. K. Surgery, Morriston
Percutaneous dilatation tracheostomy (PDT) is an evolving technique. Between March 1992 and January 1998, more than 400 percutaneous dilatational tracheostomies have been performed at the Department of Intensive Therapy, Morriston Hospital, Swansea. A small number of cases have been unsuccessful and required open tracheostomy. It is the purpose of this paper to discuss the complications and ditliculties that can arise from PDT and the measures that can be taken to minimize them.
A prospective trial comparing full and partial thickness skin for the repair of the radial free flap donor site. il. J Sidebottom.L. Stew~c J C DCV~M(I, ,I4. Moure. J. p Mrrger~nic. Regional Maxillofacial Unit. Walton Hospital. Liverpool, UK. Anecdotal reports have suggested various methods of repair of the radial donor site defect. Direct closure is likely to give the best aesthetic results, but this is often difficult to achieve. Partial thickness skin has been the accepted method of repair until recently, when full thickness grafts have been proposed. These have the stated advantages of having a donor site defect which is primarily closed and a thicker, more aesthetic recipient site result. To date, a comparative study of the outcome of these two methods has not been reported. All cases treated at the Regional Maxillofacial Unit, Walton Hospital, Liverpool having radial free flap reconstruction during the period I May 1996 to 31 December 1997 were randomly allocated to a full or partial thickness skin graft to repair the defect, A standard postoperative wound management protocol was adopted for both groups. Sixty-five patients have been assessed and the complication rates and aesthetic outcomes will be compared.
The nasolabial flap in intraoral reconstruction: a re-evaluation. !V. J ClurX, A. il. C. IV&h. G. A. Z&i. Maxillofacial Unit. Queen Alexandra Hospital, Portsmouth, UK. The nasolabial flap has historically been a versatile flap in facial and intraoral reconstruction. The use of the flap for intraoral reconstruction has reduced with the introduction of microvascular free flap reconstruction, which has undoubtedly improved the quality and scope of reconstructive options. Free flap reconstruction, however, is not without its problems: the operations are often undertaken on compromised patients with an increased risk of complications; there ih also an acknowledged failure rate of between 5 and 10%. The purpose of our review was to retrospectively assess the use of the nasolabial flap in intraoral reconstruction over a 5-year period (1993-1997 inclusive) at the Queen Alexandra Hospital, the total number of cases for this period being 16. Assessment was carried out in terms of donor site scarring, intraoral flap appearance and function (regarding speech, eating and problems of flap hair). total operative time and postoperative complications. The results and an evaluation of the flap in present-day praclice are presented.
Analysis of surgical intervention in bead and neck reconstruction. Pkghun. Regional Maxillofacial Hospitals, Liverpool, UK.
in 60 cases of free-flap compromise J. C. Devine, J S. Bwwn, E. D. Unit. Walton Hospital. Aintree
The success rate of microvascular free-tissue transfer has been reported as being between 90 and 98’%, in recent reports. The need to return to theatre to attempt salvage of a compromised free flap can overstretch available resources and may affect the recovery time of the patient. We have analysed those cases that required surgical intervention for flap salvage in an attempt to highlight those factors that may be important in case selection and surgical technique.
228
British
Journal
of Oral and Maxillofacial
Surgery
A total of 450 patients have undergone orofacial reconstruction using free-tissue transfer at the Regional Maxillofacial Unit, Walton Hospital, Liverpool between 1992 and 1997. The majority of these cases were immediate reconstructions following ablative surgery for head and neck malignancy. Surgical intervention in the immediate and early postoperative period was required in 60 cases to date, in response to clinical signs of potential or evident compromise of the free flap. We retrospectively reviewed these cases in an effort to identify and quantify causes of free-flap compromise in our series of patients and the subsequent management and outcome of free-flap salvage. A detailed account of our findings will be presented.
The use of neurotrophic factors to enhance lingual nerve repair. K. G. Smith, J M. Yates, I? II Robinson. Department of Oral and
Maxillofacial
Surgery, University of Sheffield, Sheffield, UK.
Microsurgical repair of damaged lingual nerves enhances regeneration but the level of recovery is variable and never complete. Recent studies on methods of improving recovery after peripheral nerve injury have reached a watershed, shifting from the technology of nerve repair, to the understanding of the cellular and molecular events occurring in the microenvironment of the tip of the regenerating axon. This has led to the proposed use of neurotrophic agents to support and guide axons, and hence enhance recovery. The present study investigates the efficacy of placing one of two such agents, nerve growth factor (NGF) or brain derived neurotrophic factor (BDNF) at the site of lingual nerve repair. In anaesthetized adult cats (alphaxalone and alphadolone acetate, 18 mg/kg i.m.) the left lingual nerve was sectioned and repaired by suturing the ends into a silicone tube, leaving a 1 mm gap between them. In 8 animals, the gap was filled with saline, and in each of two other groups, either 3 pg of NGF or 1 pg of BDNF (Alomone Laboratories, Jerusalem) was added. In all of the groups, the ends of the tube were sealed with feline fibrin glue. After recovery for 6 months the extent of functional recovery was evaluated electrophysiologically. The study found significant differences between the repair groups. NGF at the repair site resulted in an increase in the number of thermosensitive units, and both neurotrophic factors were followed by a reduction in conduction velocity; this would be compatible with an increase in axonal sprouting at the injury site. There was, however, no overall improvement in recovery. Thus, the application of these particular neurotrophic agents did not significantly enhance lingual nerve regeneration. Supported
by the Welleome
Trust
A histopathological and physical study of the bonding of ~50 composite resin to bone. M. J Hahn, R. M. Browne, .! W Frame, J G. Meechan, JR McCabe, ? Budaiya. Department of Oral and Facial
Surgery, Sunderland Royal Hospital, Sunderland; Dental Schools of Universities of Birmingham and Newcastle upon Tyne, UK. The aims of this study were to determine the histological response of bone to P50 composite resin using two different bonding agents - ART and All Bond-2 - and to measure the associated bond strengths. No histological data were found in the literature concerning the effects of bonding composite resin to bone in vivo. Shear bond strength determination of the adhesion of P50 to bone in vitro has been carried out previously. In this study, P50 was bonded to both the cortical and cancellous parts of the calvarial bone of 24 rabbits using surgically roughened areas and titanium discs as controls. The histological changes at one, four and eight weeks were compared. In the same rabbits, two composite discs were bonded to tibia1 bone and the shear bond strengths determined at the same time intervals. The results indicated that P50 composite resin can be bonded to vital bone without any significant adverse clinical or histological effects. The bond strengths (0.25-21.66 MPa) achieved were sufficient to justify further studies into the possible use of these materials for fracture fixation.
Bioglass@ Thompson,
4585 as a mouldable bone graft substitute. C. Chan, I. l? Robinson, P Revell, 1 Wilson, L. Hench. UMDS
Guy’s Hospital, London, UK. Introduction: Bioglass@ particulate has been shown to be bioactive in hard and soft tissues. However, used alone, it may be insufficiently cohesive for certain augmentation procedures. Addition of high-molecular-weight Dextran produces a mouldable bioactive material. Objective: To evaluate the behaviour of the bioactive putty in a femoral defect in rabbits. Materials and methods: Defects were created in the lateral femoral condyles in 51 New Zealand white rabbits and filled with one of the following: (1) autogenous bone; (2) BioglassQ (3) Bioglass@ mixed with Dextran; (4) mixture of (2) and autogenous bone; (5) mixture of (3) with autogenous bone. Six defects were left unfilled as controls. Healing of bony defects at two days, one, two, three, six and twelve weeks were studied histologically using Von Kossa, toluidine blue and vital bone markers. Results: There was no evidence of toxicity and all test sites were filled by the third week. Particulate was gradually incorporated into the new trabecular bone and was almost completely undetectable at 12 weeks. Control sites showed little or no infill. Conclusion: No difference between Bioglass@ and autologous bone was detectable and the addition of Dextran was without effect.
The osseointegration M. A. El Montaser,
of implants H. Devlin,
in laser-prepared bone. R. E. Lloyd, I? Sloan, M. Dickinson. University
Dental Hospital of Manchester, Manchester, UK. The object of the study was to determine the bone turnover surrounding titanium screw implants placed with an erbium-YAG laser, using a rat calvarial model. In each rat, a sagittal incision was made in the skin of the skull under general anaesthesia, and the periosteum gently reflected. A hole on each side of the calvaria was prepared with either the erbium-YAG laser or a metal burr. The bone was cooled continuously with physiological saline. After preparing the holes, selfthreading titanium screws were placed (diameter 1 mm) and the overlying tissues approximated and sutured. The rats were killed after 3 weeks. The lasered defects healed with a different histological pattern from the burr prepared defects. With the lasered defects, vital bone was deposited on a thin zone of necrotic bone. A layer of carbonization separated the vital from the non-vital tissue. The dura was perforated, and the laser caused a deeply penetrating fibrosis and oedema of the brain tissue, which was not present with the burr prepared defects. With both lasered and burr prepared defects, bone was deposited around the head of the implant outline at the ectocranial surface. A different histological pattern surrounds titanium implants placed with an erbium-YAG laser from those placed with a burr.
Towards a diagnostic index for investigation A. S. Davies, D. K. Riden, P Dubbins.
Maxillofacial Surgery Plymouth, Devon, UK.
and
of salivary
gland disease.
Departments of Oral & Radiology, Derriford Hospital,
The results of management of patients in Plymouth with disease of the major salivary glands was reviewed retrospectively. The diagnoses were grouped and the various investigations used were assessed for effectiveness and relevance in establishing the final diagnosis. The diagnostic groups studied were benign neoplasia, malignant salivary lesions, degenerative conditions, inflammatory or infective presentations, calculous and chronic obstructive disease and non-salivary lesions. The investigations used were clinical examination, ultrasound scanning, FNAC, plain radiography, CT or MRI scanning and sialography. Sensitivities, specificities and predictive values were derived for each modality in the diagnosis of each group. An index of diagnostic power was derived for each of the modalities. The factors affecting the clinical usefulness of each