The document discusses Minimally Invasive Surgical Techniques (MIST) in periodontal surgery. It provides an overview of the history and rationale for MIPS, describing key features such as smaller incisions, limited flap elevation using sharp dissection only, use of microscopes and microinstruments, and microsuturing techniques. MIPS has advantages like reduced trauma, improved wound stability and closure, and less post-operative discomfort. The document reviews studies supporting the efficacy and effectiveness of MIPS and recent developments in the approach, including use of a videoscope and potential future applications of robot-assisted surgery.

1. MINIMALLY INVASIVE
SURGICAL TECHNIQUES
(MIST)
DR. THASLIM FATHIMA
DEPARTMENT OF PERIODONTOLOGY
1

2. CONTENTS
INTRODUCTION
HISTORY
RATIONALE
FEATURES OF MINIMALLY INVASIVE PERIODONTAL SURGERY (MIPS)
- INCISION
- FLAP ELEVATION
- USE OF MICROSCOPE
- SUTURING
EFFICACY & EFFECTIVENESS OF MIPS
RECENT UPDATION
DISADVANTAGES OF MIPS
CONCLUSION
REFERENCES

3. INTRODUCTION
Conventional periodontal surgical therapies involve extensive tissue reflection
resulting in morbidity like thermal sensitivity, food impaction, and compromised
esthetics.
The clinical innovation in periodontal flap design and handling has radically changed
surgical approach, which has allowed a drastic reduction in wound failure when
compared to conventional flap approach.
MIST

4. Data from controlled clinical trials and meta analyses from systematic reviews
demonstrate that minimal invasion approaches provide added benefits in terms of
clinical attachment level gain and probing pocket depth reduction as compared with
access flap alone.
These include barrier membranes, demineralized freeze dried bone allograft, a
combination of barrier membranes and grafts and enamel matrix derivative (EMD).

5. 5
In fact, flap dehiscence at regenerative sites is a frequent occurrence with barrier membranes,
bone grafts combination of barriers and grafts and, to a lesser extent, with EMD.
Exposure and thus contamination of the regenerative material is a critical issue because it has
been associated with reduced clinical outcomes.
Thus, in order to further increase surgical effectiveness, the use of operating microscopes and
microsurgical instruments in terms of MIPS has been suggested.

6. • MIPS technique allows for minimization of soft tissue trauma and the removal of
granulation tissue from periodontal defects using a much smaller surgical incision than
that used in standard bone graft techniques.
• MIPS can be used for patients who have many isolated defects, so long as the incision at
one site does not connect with the incisions at other sites to become a continuous
incision.

7. HISTORY
• The term “minimally invasive surgery” was first coined by the general
surgeons Filtzpatrick and Wickham in 1990.
• The concept of “minimally invasive surgery (MIS)” is one such peculiar
and innovative approach which aims to produce minimal wounds,
minimal flap reflection, and gentle handling of the soft and hard tissues
(Harrel et al. 2005).
• It was further explored by Hunter and Sackier in 1993. They defined
minimally invasive surgery as the ability to perform a traditional
surgical procedure and achieve the same or better outcomes utilizing a
surgical opening that was smaller than the traditional surgical access.

8. • MIS was first introduced into the periodontal field with intent to treat multiple and isolated periodontal
intrabony defects in 1995.
• Minimally invasive surgery for periodontal therapy was introduced by Harrel SK in 1998.
OBJECTIVES (1) minimal mesiodistal extension of periodontal flap,
(2) minimal flap elevation to expose only 1 to 2 mm of alveolar bone,
(3) to avoid placement of vertical incision, but if necessary confined within attached
gingiva and not extending beyond mucogingival junction, and
(4) to avoid periosteal incision

9. • The use of microscope in periodontal surgeries for better
visualization during manipulation and suturing of soft
tissues was introduced by Tibbetts and Shanelec.
• The techniques were then called as “periodontal
microsurgeries” mainly to address the techniques aided by
a specific technology such as microscopes.
• A broader term “minimally invasive periodontal surgery”
(MIPS) was introduced later to describe the smaller more
precise surgical techniques that are possible through the
use of operating microscopes and other technologies that
are beginning to be available for the use in periodontal
surgery.

10. RATIONALE
Reduction of surgical trauma
Increase in flap/wound stability
Improvement of primary closure of the wound
Reduction of surgical chair time
Minimization of intra-operative and post-operative patient discomfort
and morbidity

11. USE OF
MICROSCOPESUTURING
FLAP
ELEVATION
INCISION
FEATURES OF MIPS

12. INCISION
• MIPS technique allows for minimization of soft tissue trauma and the
removal of granulation tissue from periodontal defects using a much
smaller surgical incision than that used in standard bone graft
techniques.
• The incisions are designed to preserve as much of the soft tissue as
possible. It is started with intra-sulcular incisions surrounding the teeth
adjacent to the defect.
• These incisions are not connected across the interproximal tissue and
should be made as separate incisions to preserve the inter-proximal
tissue.

13. • The 2 intrasulcular incisions are connected with a single horizontal incision that is placed 2–3 mm
from the crest of the papilla.
• When the surgery is being performed in an esthetic area, such as the maxillary anterior, this
horizontal incision will usually be placed on the palatal aspect of the papilla. This will help to
preserve the shape of the papilla as well as cover the grafted site with soft tissue.
• In a nonesthetic area, the horizontal incision can be placed either buccally or lingually as needed to
better cover the grafted site with soft tissue.

14. • The use of Tunnel Technique (TT) in periodontal surgery is considered an important element of
MIPS.
• This technique is originated primarily from the Envelope Technique (ET) developed by Raetzek
in 1985 for the treatment of single gingival recessions.
• In the TT, intrasulcular incisions are first initiated and then followed by supraperiosteal
preparation of a tunnel through the defect areas.
• This will allow the transplantation of subepithelial connective tissue graft (SCTG) in the sulcular
areas.

16. • Single Incision Technique (SIT), described by Hurzeler and Weng, for the extraction of SECTG from the
palate, is more preferable than using Trap Door Incision Technique (TDIT).
The Single-lncision Palatal Harvest
Technique: A Strategy for Esthetics
and Patient ComfortEduardo R. Lorenzana.
(lnt J Periodontics Restorative Dent 2000;20:297-305

18. FLAP ELEVATION
• In MIPS, the flaps are elevated utilizing sharp dissection only. This could be achieved by means of
Orban knives that have been reshaped to one third to one fourth of their original size.

20. • When blunt dissection has been used to elevate MIPS flaps, obvious blanching of the reflected
tissue has been noted. This often leads to a darkened bruised appearance of the flap at the time of
closure.
• When this bruised appearance is present, an increased incidence of postsurgical flattening of the
papilla, interproximal cratering, and loss of soft tissue height is observed compared with when
only sharp dissection has been used.
• The use of sharp dissection minimizes trauma to the flap and preserves much of the blood supply
to the soft tissue.
• The lack of embarrassment of the blood supply to the flap is a probable reason for the improved
soft tissue healing and the minimization of postoperative soft tissue changes that have been
reported following the use of MIPS.

22. PAPILLA PRESERVATION
FLAP
• Specific surgical approaches have been reported to prevent
or reduce an excessive apical displacement of the gingival
margin in the treatment of periodontal defects.
• Takei et al. proposed a new surgical approach called the
papilla preservation technique.

24. • Cortellini et al. published a modification of Takei's technique
as a new approach for interproximal regenerative procedures
called (the modified papilla preservation technique).
• A horizontal incision is performed on the buccal papillary
tissue at the base of the papilla. A fullthickness palatal flap,
which includes the interdental papilla, is elevated.
• A buccal full thickness flap is elevated with vertical releasing
incisions and/or periosteal incisions, when needed. A barrier
membrane is positioned to cover the defect. The interdental
tissues are repositioned and sutured to completely cover the
membrane.

25. • This technique is applicable in wide interdental spaces (2 mm), especially in the anterior
dentition. This technique allows for achieving primary closure of the tissue and preserving
the papilla in 75% of cases.

26. • Cortellini et al. proposed the simplified papilla preservation flap (SPPF). It
is initiated with an oblique incision across the defect associated papilla, from
the gingival margin at the buccal line angle of the involved tooth to the
midinterproximal portion of the papilla under the contact point of the
adjacent tooth.
• A full thickness palatal flap, including the papilla, and a split thickness
buccal flap are then elevated.
• The interdental tissues are positioned and sutured to obtain primary closure
of the interdental space. The SPPF is applicable in narrow interdental spaces
(2 mm).

27. Whales tail technique
• Bianchi and Basseti in 2009 introduced a surgical technique to preserve interdental tissue in guided tissue regeneration
known as a “whale’s tail” technique. It was used for the treatment of wide intrabony defects in the esthetic zone
involving the elevation of a large flap from the buccal to the palatal side to allow accessibility as well as visibility of the
intrabony defect and to perform GTR while maintaining interdental tissue over grafting material.

29. MIST

30. • More recently, Cortellini and Tonetti described a modified surgical approach of the minimally invasive
surgical technique (modified minimally invasive surgical technique, M-MIST) to evaluate its applicability
and clinical performances in the treatment of isolated deep intrabony defects in combination with
amelogenins.
• The M-MIST consisted of a buccal incision of the defect associated papilla, according to the principles of
the papilla preservation techniques. Only a buccal flap was raised while the interdental papilla was left in
situ.

31. Modified – minimally invasive surgical
technique

33. The tunnel technique
This tunneling under
the papillae and
lateral extension of
the pouch
facilitate the passive
coronal
advancement of the
pouch, thus
eliminating the
need for vertical
releasing incisions as
well as papillary
incision

35. Mis technique

36. Pin hole video

37. Pin hole technique
Reddy SS. Pinhole surgical technique
for treatment of marginal tissue
recession: A case series. J Indian Soc
Periodontol 2017;21:507-11

39. Visualization
USE OF MICROSCOPE
• The use of magnification and optimal illumination of the surgical field in MIPS greatly
improves the visual acuity and the control of the surgical instruments, making it possible to
perform surgery with reduced flap reflection.
• Thus, in order to further increase surgical effectiveness, the use of operating microscopes and
microsurgical instruments in terms of MIPS has been suggested, and the use of a microsurgical
approach in combination with different regenerative materials resulted in maintenance of
primary wound closure in more than 92% of the treated sites for the whole healing period.

40. Periodontal microsurgical techniques have been described by Tibbetts and Shanelec

41. • During MIPS, it is often necessary to visualize the defect from several angles
to verify the debridement areas of the osseous defect or the root surfaces.
• It is difficult to move a surgical microscope from one visualization angle to
another rapidly.

42. Head banded microscope

44. • In order to guarantee atraumatic surgical approach in the MIPS, the use of
miniaturized operation instruments is considered to be of great importance.
Generally, a useful microsurgical tray for the routine use in MIPS should include:
• (1) microraspatorium
• (2) bone scraper
• (3) papilla elevatorium
• (4) microscalpel holder
• (5) needle holder
• (6) microscissor
• (7) dental microforceps.

47. Defect Debridement
• The granulation tissue is removed using a curette with its tip inserted vertically into the defect and its shank
held parallel to the long axis of the tooth.
• This will minimize the trauma to the flap. The ultrasonic scaler can be additionally used to break up the
granulation tissue into smaller fragments. A granulator can also be utilized to remove the remaining
granulation tissue. Final root planing and smoothening is accomplished with a highspeed surgical length
finishing bur.

48. SUTURING
• An important element of MIPS is the use of suitable microsuturing.
• This includes the materials to be used as well as the suturing technique itself. From minimally
invasive point of view, monofilament suturing materials are atraumatic, whereas polyfilament
suturing materials may carry the “wicking action” and therefore contribute to wound
contamination from saliva.

50. Periodontal videoscope
• The term Videoscope assisted minimally invasive surgery (V-MIS) is used to
describe MIS performed with the aid of a videoscope.
• Proper visualization of the surgical site is of utmost importance in MIS.
Hence a videoscope comprising of a small digital camera was developed.
• This camera when placed at the surgical site provides direct visualization and
greater magnification (Harrel et al. 2012, 2013).

51. PERIODONTAL VIDEOSCOPE
Harrel SK et al in 2014 conducted a study to evaluate residual defects
following non-surgical therapy consisting of root planing with local
anaesthetic.
V-MIS was performed utilizing the videoscope for surgical
visualization. Re-evaluation, 6 months post-surgery, showed
statistically significant improvement in mean PPD and CAL (PPD
3.88±1.02 mm, CAL 4.04±1.38 mm) in 1, 2, and 3 wall defects.

53. ROBOT-ASSISTED MINIMALLY INVASIVE SURGERY (RMIS)
• Robot-assisted minimally invasive surgery (RMIS) promises to be a evolutionary
step towards refining MIS.
• It would greatly improve the accuracy and dexterity of a surgeon while
minimizing trauma to the patient.
• Robotically assisted minimally invasive surgery uses robotic arms to perform the
actual surgery on the patient.
• These arms can either be controlled by a telemanipulator or through computer
control.

54. • In the telemanipulator approach, the surgeon performs the normal movements associated with the
surgery while the robotic arms replicate them onto the patient.
• The computer controlled approach allows the surgeon to use a computer to control the robotic arms.
• However; clinical studies using RMIS have shown only marginal success.
• A major disadvantage includes large size footprints and cumbersome robotic arms.
• Due to feasibility constraints, long term studies using RMIS have not been conducted.

55. INDICATIONS
1. An ideal site for bone grafting using MIPS is an ISOLATED, usually interproximal defect that does
not extend significantly beyond interproximal site.
2. Less than ideal site is a defect that extends to buccal and/or lingual from interproximal area
3. Defects that border on an edentulous area
4. MIPS can be used for patients who have many isolated defects, so long as the incision at one site
does not connect with incisions at other sites to become a continuous incision.

56. CONTRAINDICATIONS
Generalized horizontal bone loss or multiple
interconnected vertical defects are thought to be
contraindicated for MIPS and are best handled
with more traditional surgical approaches.

57. ADVANTAGES
1. MIPS has a high potential for achieving and maintaining primary closure leading to less contamination from
oral environment
2. Soft-tissue height and contour are mostly preserved leading to minimal gingival recession meeting the
demands of patients and clinician in the esthetic zone. These distinguishing features of MIS might be attributed
to decreased tissue manipulation, lessened overall trauma, and enhanced blood supply to the surgical sites
33 This technique allows for minimization of soft-tissue trauma and removal of granulation tissue using much
smaller surgical incision than standard surgical procedure
4. Gentle handling of tissue leads to less postsurgical complications such as pain, swelling, and flap dehiscence.
5.. Uninvolved areas can be spared by decreasing surgical area span.

58. DISADVANTAGE
• According to Jaffray disadvantages of minimally invasive surgery, in general, are related
to the fact that
1. It requires special equipment
2. Specialist training is probably required
3. Some additional equipments could be more expensive
4. Some procedures may take longer than usual, compared with conventional surgeries.

61. CONCLUSION

62. REFERENCES
• Minimally invasive periodontal therapy -clinical techniques and visualization technology. Stephen K. Harrel, thomas G.
Wilson jr.
• Carranza’s clinical periodontology, 12th ed.
• Harrel sk. A minimally invasive surgical approach for periodontal regeneration: surgical technique and observations. J
periodontol. 1999;70:1547–1557.
• Cortellini p, tonetti ms. Minimally invasive surgical technique and enamel matrix derivative in intrabony defects . I:
clinical outcomes and morbidity. J clin periodontol. 2007;34:1082– 1088.
• Harrel sk, wilson tg jr, riverahidalgo f. A videoscope for use in minimally invasive periodontal surgery. J clin periodontol.
2013;40:868–874.
• Jan lindhe, clinical periodontology and implant dentistry, 5th ed.
• Aous dannan, minimally invasive periodontal therapy. J indian soc periodontol. 2011 octdec; 15(4): 338–343.
• Wickham j. Minimally invasive therapy. Health trends. 1991;23:6–9.