This is an seminar on short implants related to implant dentistry . This gives the insight on what has happened since the evolution of short implants and its role in implantology .Their role as replacement of missing tooth in the atrophied maxillary and mandibular posterior regions

1. Presented by

2. Contents
Introduction
History
Indications
Risk factors
Implant Length selection
Stress repartition and crown to implant length ratio
Stress minimizing surgery
Survival rate
Conclusion

3. Introduction
Earlier studies have quoted that any implant less than 10mm is considered as
short implants.
According to Nisand D and Renouard F (2014).
A short implant will be defined as an implant with a designed intrabony length of
less than or equal to 8mm.
An extra-short implant as an implant with a designed intrabony length of less
than or equal to 5mm.
2011- European Association of Dental Implantologists in the 6th European
Consensus conference approved Olate et al classification of implants ; Which is
Short implants are – Less than 8mm
Medium implants- 9-13mm
Long implants – Greater than 13 mm
What are short implants?

4. Shortimplant
In place!
A) Preoperative cone beam computed tomography scan of a missing left
first molar showing 9.5 mm of available bone above the inferior alveolar
nerve.
(B) Soft tissue healing 2 months after the placement of a short-length
implant (8 mm in length and 5 mm in diameter).
(C) Periapical radiograph 3 years after loading.
(D) Clinical view of the prosthetic restoration after 3 years of loading

5. History
1968 - Thomas driskell –
Bicon system of dental
implants - 8mm of length.
1979 – Branemark –
7mm implant.
2008 - Bicon system –
5mm implant
2013-Straumann - 4-mm
Roxolid implant
When?

6. Indications
 In areas of reduced height such as maxillary posterior
and mandibular posterior region following tooth
extraction.
 Severely resorbed edentulous mandible
 To support single and multiple fixed restoration in the
posterior jaws
What is the need for short
implants?

7. Merits
 The main advantage of using short implants is that it
simplifies the implant surgery by avoiding the more
invasive procedures like bone grafting, sinus lifting,
nerve repositioning, etc., and thus decreases morbidity
and reduces the healing period
 It reduces the duration period of the treatment and the
cost factor.
 The poor quality of bone in the posterior region
especially in the maxilla where short implants are
mostly used is another contributing factor.
What are the advantages?

8. RiskFactors
 Existing periodontal disease
 Smoking habits
 Age factor
 Systemic diseases
What are the risk factors?

9. ImplantLength
Selection
 Over years the longest implant possible is always
placed to improve the stability and crown to root ratio
and bone to implant contact
 Nowadays bone to implant contact may also be
improved by the use of micro rough surfaces.
 Adequate implant primary stability can be achieved
through adapted surgical preparation and new
implant designs.
 There are clinical situations in which the entire
available bone should not be used instead the surgeon
should do three dimensional plan for implant
placement with limited resources.
What is the ideal length?

10. Implantdiameter
 Increasing the diameter of the implant is an effective
method to increase the implant surface area.
 Wider diameter short implants will have increased FSA
and improved primary stability.
 It allows engagement of a maximal amount of bone and
better distribution of stress in the surrounding bone.
 An increase in the diameter reduces stress at the implant
neck and is associated with good distribution of force
compared with increases in implant length.
 Implant strength and fracture resistance can be improved
by increasing the diameter of the implant.
 Wider implants also facilitate the creation of a better
emergence profile, especially in the posterior segment.
 An increase in diameter by 1 mm will increase the surface
area by 30–200% depending on the implant design.
What is the role of implant
diameter?

11. Surfacetopography
 Most of the earlier studies using short implants
showed less favorable results as compared to longer
implants because of the use of machined surface
implants.
 The fact that alteration of the implant surface can
influence the success of Osseo integration has been
proven in various studies.
 This can be achieved by either subtractive processes
like blasting, etching and oxidation, or additive
processes like titanium plasma spraying,
hydroxyapatite and other calcium phosphate coating
and ion deposition
 Rough implants offer extensive area for Osseo
integration. It increases the BIC and FSA in addition
to improve the wettability of the implant surface.
What is the role of surface
topography?

12. Photofunctionalization
ofimplants
 Treatment of implants with ultraviolet (UV) light has been found to
increase the BIC from 55% to near maximum level of 98.2%.
 This resulted in 3-fold increase in the strength of Osseo integration.
 This increase is attributed to the generation of super hydrophilicity,
a significant decrease in surface hydrocarbons, and improvement in
the electrostatic status of titanium surfaces after UV treatment.
 The biological effects along with UV-enhanced surface properties
are collectively defined as photofunctionalization of titanium
implants.
What is the effect of photo
functionalization on implants?

13. Macrogeometric
design
 Modifications in the macro geometry of the implant are
advantageous in providing more area for BIC and FSA.
 Various thread shapes such as square, v-shaped, and
reverse buttress are available for implants of which
square threads provide more surface area for a given
length of the implant.
 Increasing the number of threads per unit area
(decreased thread pitch) and increasing the thread
depth also enhance the FSA of short implants.
Role of macro geometric design

14. Continued
Macro geometry

15. Bonedensity
 Bone density is directly proportional to its strength.
Less dense bone may demonstrate a reduction of its
strength by 50-80% compared to higher density bone.
 Poor bone quality is strongly linked to higher failure
rates in implants.
 Increased failure rates of short implants in the early
trials were attributed to the use of machined implants
in poor quality bone, especially in the posterior
maxilla.
 This negative effect is somewhat dampened by rough
surfaced implants now. Use of self-tapped implants has
also brought down the failure rates.
 Use of bone expanders/condensers during osteotomy
procedure also improves the bone density and there by
increases the success of a short implant.
Role of bone density

16. Crown-Implant
ratio
Anatomical and Clinical Crown to
Implant ratio
Güngör H (2016) studied the effects of C/I ratio using a 3-D
finite element analysis on stress distribution both in bone and
implant under axial and oblique loads. They found that the
high C/I ratio affected both cortical and cancellous bone along
with the implant under oblique and axial load with more
stress under oblique load when compared to axial load.

17. Continued
 It has been proposed by Misch, that the higher the
crestal stress, the higher the risk of crestal bone loss,
and the higher the stress factor throughout the
implant, the greater the risk for implant failure.
 Increasing C/IR amplifies the moment arm for any
offset occlusal loads
 Technical complications resulting due to increased
CIRs are loosening of the screw, decementation of the
crown, food accumulation in the interdental spaces and
occlusal strain. And the biological hitches include peri-
implantitis, formation of deep pockets, poor oral
hygiene, pain, swelling, bleeding gums and transient
paresthesia.
Crown implant ratio

18. Continued
 Increased crown implant ratio (CIR) is a major concern
with short implants.
 A 1:1.5 crown root ratio is suggested as most favorable
and 1:1 as a minimum for a tooth abutment.
 short implants and the ideal CIR has not been
established.
 Various studies have demonstrated high success rates
with a CIR of up to 2 and increased CIR did not result
in additional peri-implant bone loss.
 This was possible by giving due considerations for
various stress reduction methods like avoiding lateral
loads, cantilevers, etc.
Crown to implant ratio

19. IncreasedCrown
to implantratio
Crown -
Implant
ratio
Irregular
Stress
repartition
Marginal
boneloss
Pocket
formation
Implant
failure

20. Stressrepartition
andcrownto
implantlengthratio
 A dogma states that the prognosis of abutment teeth
and prosthetic rehabilitation is related to the crown-to-
root ratio.
 According to this statement, it is assumed that for
successful prosthetic rehabilitation the crown-to-root
ratio should always be ≤1.
 These guidelines are emprically used for implants
 According to the definition provided by Blanes et al.,
two types of crown-to-implant ratio can be established
1.The anatomical crown-to-implant ratio; and
2.The clinical crown-to-implant ratio
What is stress repartition?

21. Survivalrateofshort
implants
 Annibali et al. 2012 in their systemic analysis and
meta-analysis of short implants (less than 10mm)
concluded that the provision of short implant-
supported prostheses in patients with atrophic alveolar
ridges appears to be a successful treatment option in
the short term; however, more scientific evidence is
needed for the long term’.
 Jokstad . 2011 in his systematic review of short
implants (less than 10mm) concluded that there is
growing evidence that placement of short (<10 mm)
implants can be successful in the partially edentulous
patient.
Survival rate

22. Survivalrate
Survival of the fittest
 Neldam & Pinholt (2012) in their systematic review on
short implants (≤8 mm) concluded that Short implant
length was not related to observation time, installment
region, failures, and dropouts were not specified;
subsequently, it was not possible to perform a meta-
analysis
 Renouard & Nisand (2006) in their structured
systematic review concluded that The use of a short
implant may be considered in sites thought to be
unfavourable for implant success, such as those
associated with bone resorption or previous injury and
trauma. Whilst in these situations implant-failure
rates may be increased, outcomes should be compared
with those associated with advanced surgical
procedures such as bone grafting, sinus lifting and the
transposition of the alveolar nerve’

23. ShortvsLong
 Felice et al (2011) in their Randomised controlled trial
using short implants, long implants, sinus lift
procedure concluded that Significantly more
complications occurred in augmented patients. Their
pilot study suggests that short implants may be a
suitable, cheaper and faster alternative to longer
implants placed in augmented bone.
Survival rate?

24. Shortimplants
vs
Longimplants
 Uehara P N et al (2018) in their meta – analysis of Randomized
controlled trials to compare the marginal bone loss and survival
rate of short implants with long implants in augmented bone areas
of posterior atrophied maxilla and concluded that short implants
had a similar survival rate as that of the longer implants placed in
the bone augmented areas. They also concluded that short
implants is a predictable alternative for rehabilitation of atrophied
posterior regions.
Survival rate?

25. Biomechanical
methodsofstress
reduction
 Biomechanical methods to decrease the stresses to
short implants are a critical factor in deciding the
success of the treatment.
 These include decreasing force to the implant
prosthesis and increasing implant surface area of
prosthesis support

26. Stressminimizing
surgery
 In 2011, the European Association of Dental
Implantologists concluded its consensus conference on
short implants with the following recommendation to
avoid complications: ‘the implant surgeon and
restorative dentist should have adequate clinical
experience’
 The factors in consideration are
1.Experience
2.Non technical human factors
3.Morbidity

27. Experience
 Studies of neurocognitive activity show that the part of the brain
that manages both complex and novel procedures lies in the
prefrontal cortex, the most anterior region of the brain. Tasks
utilizing the prefrontal cortex require conscious effort and,
importantly, consume vast cognitive resources.
 Complex tasks, such as surgical procedures, as well as tasks that
are unfamiliar, require the prefrontal cortex to remain active and
the brain’s full resources to remain accessible. However, under
some conditions, specifically stress, fatigue and burnout, this
accessbecomes impaired.
How experience of the practitioner
plays a crucial role?

28. Roleofexperience
Advanced surgical
procedures
Access to pre-frontal
cortex
Beginners its
inaccessible at times
With practice
Use of pre-frontal
cortex is less
required
The function of pre-
frontal cortex
becomes the function
of the Limbic system
of the brain
Increase in experience Errors are
narrowed down and the procedure
is made in to simple.

29. Non-technical
humanfactors
 Many nontechnical parameters, such as stress, fatigue,
overconfidence and the lack of preparation or
organization, can influence the outcome of a procedure.
 Stress is probably one of the complicating factors
shared most widely by dental and maxillofacial
surgeons.
 It is difficult for most practitioners to manage both the
technical and emotional aspects of a patient who is
usually under local anaesthesia.
Role of non-technical human
factors

30. Stress
Dental surgeon
Advanced
surgical
procedure
Stress
Diminishing of
cognitive
abilities
Incapable of
making rationale
decisions
Mental
tunnelling
Two possible
reactions
Number:1 –
Fight or Flight
response
Number:2 -
Vigilance
stress as a conflict of resource
mobilization and accessibility: when knowledge exists
but it is not immediately available when needed,
stress occurs.

31. Morbidity
Morbidity, defined as the set of complications
that may accompany a surgical procedure, is
rarely taken into account during therapeutic
choices.
In 2005, Enislidis et al. reported an implant
survival rate of 96% following 45 distraction
surgeries of 37 patients. Nevertheless, the
authors also identified a 65% complication
rate, of which 21% experienced serious
complications, including three mandibular
fractures . Although the implant success rate
in this study was satisfactory, it was obtained
at the cost of substantial morbidity
Morbidity as a factor

32. Morbidity The morbidity of
short implants is
low, and the loss of
a short implant
usually has only
minor
consequences.
Sometimes it is
possible to re-
implant; whereas,
in other situations
the use of advanced
surgical techniques
becomes necessary.
Patients must be
warned about these
risks before
undergoing implant
treatment.
Short implants

33. Conclusion
 Short-length implants can be successfully used to
support single and multiple fixed reconstructions in
posterior atrophied jaws, even with increased crown to
implant ratios.
 The use of short-length implants allows treatment of
patients who are unable to undergo complex surgical
techniques for medical, anatomic or financial reasons.
 Moreover, the use of shortlength implants in clinical
practice reduces the need for complex surgeries, thus
reducing morbidity, cost and treatment time

34. References
 Nisand D, Renouard F. Short implants in limited bone volume.
Periodontol 2000. 2014;66:72–96.
 Shah AK. Short implants - When, where and how?. J Int Clin Dent
Res Organ 2015;7:132-7.
 Shetty S, Puthukkat N, Bhat SV, Shenoy KK. Short implants: A
new dimension in rehabilitation of atrophic maxilla and mandible.
J Interdiscip Dentistry 2014;4:66-70.
 Blanes RJ. To what extent does the crown-implant ratio affect the
survival and complications of implant-supported reconstructions? A
systematic review Clin Oral Implants Res 2009: 20(Suppl 4): 67–
72.
 Felice P, Checchi V. Bone augmentation versus 5-mm dental
implants in posterior atrophic jaws. Fourmonth post-loading
results from a randomised controlled clinical trial. Eur J Oral
Implantol. 2009;2:267–81.

35. Thank you!